@copying
This section of the manual was derived from the upstream OpenGL
-documentation. Each function's documentation has its own copyright
-statement; for full details, see the upstream documentation. The
+documentation. Each function's documentation has its own copyright
+statement; for full details, see the upstream documentation. The
copyright notices and licenses present in this section are as follows.
-Copyright @copyright{} 1991-2006 Silicon Graphics, Inc. This document is
-licensed under the SGI Free Software B License. For details, see
+Copyright @copyright{} 1991-2006 Silicon Graphics, Inc. This document
+is licensed under the SGI Free Software B License. For details, see
@uref{http://oss.sgi.com/projects/FreeB/,http://oss.sgi.com/projects/FreeB/}.
-Copyright @copyright{} 2003-2005 3Dlabs Inc. Ltd. This material may be
+Copyright @copyright{} 2003-2005 3Dlabs Inc. Ltd. This material may be
distributed subject to the terms and conditions set forth in the Open
Publication License, v 1.0, 8 June 1999.
@uref{http://opencontent.org/openpub/,http://opencontent.org/openpub/}.
-Copyright @copyright{} 2005 Addison-Wesley. This material may be
+Copyright @copyright{} 2005 Addison-Wesley. This material may be
distributed subject to the terms and conditions set forth in the Open
Publication License, v 1.0, 8 June 1999.
@uref{http://opencontent.org/openpub/,http://opencontent.org/openpub/}.
-Copyright @copyright{} 2006 Khronos Group. This material may be
+Copyright @copyright{} 2006 Khronos Group. This material may be
distributed subject to the terms and conditions set forth in the Open
Publication License, v 1.0, 8 June 1999.
@uref{http://opencontent.org/openpub/,http://opencontent.org/openpub/}.
@table @asis
@item @var{op}
-Specifies the accumulation buffer operation. Symbolic constants
+Specifies the accumulation buffer operation. Symbolic constants
@code{GL_ACCUM}, @code{GL_LOAD}, @code{GL_ADD}, @code{GL_MULT}, and
@code{GL_RETURN} are accepted.
@item @var{value}
Specifies a floating-point value used in the accumulation buffer
-operation. @var{op} determines how @var{value} is used.
+operation. @var{op} determines how @var{value} is used.
@end table
-The accumulation buffer is an extended-range color buffer. Images are
-not rendered into it. Rather, images rendered into one of the color
+The accumulation buffer is an extended-range color buffer. Images are
+not rendered into it. Rather, images rendered into one of the color
buffers are added to the contents of the accumulation buffer after
-rendering. Effects such as antialiasing (of points, lines, and
+rendering. Effects such as antialiasing (of points, lines, and
polygons), motion blur, and depth of field can be created by
accumulating images generated with different transformation matrices.
Each pixel in the accumulation buffer consists of red, green, blue, and
-alpha values. The number of bits per component in the accumulation
-buffer depends on the implementation. You can examine this number by
+alpha values. The number of bits per component in the accumulation
+buffer depends on the implementation. You can examine this number by
calling @code{glGetIntegerv} four times, with arguments
@code{GL_ACCUM_RED_BITS}, @code{GL_ACCUM_GREEN_BITS},
-@code{GL_ACCUM_BLUE_BITS}, and @code{GL_ACCUM_ALPHA_BITS}. Regardless of
-the number of bits per component, the range of values stored by each
-component is @r{[-1,1]}. The accumulation buffer pixels are mapped
+@code{GL_ACCUM_BLUE_BITS}, and @code{GL_ACCUM_ALPHA_BITS}. Regardless
+of the number of bits per component, the range of values stored by each
+component is @r{[-1,1]}. The accumulation buffer pixels are mapped
one-to-one with frame buffer pixels.
-@code{glAccum} operates on the accumulation buffer. The first argument,
+@code{glAccum} operates on the accumulation buffer. The first argument,
@var{op}, is a symbolic constant that selects an accumulation buffer
-operation. The second argument, @var{value}, is a floating-point value
-to be used in that operation. Five operations are specified:
+operation. The second argument, @var{value}, is a floating-point value
+to be used in that operation. Five operations are specified:
@code{GL_ACCUM}, @code{GL_LOAD}, @code{GL_ADD}, @code{GL_MULT}, and
@code{GL_RETURN}.
All accumulation buffer operations are limited to the area of the
current scissor box and applied identically to the red, green, blue, and
-alpha components of each pixel. If a @code{glAccum} operation results in
-a value outside the range @r{[-1,1]}, the contents of an accumulation
+alpha components of each pixel. If a @code{glAccum} operation results
+in a value outside the range @r{[-1,1]}, the contents of an accumulation
buffer pixel component are undefined.
The operations are as follows:
@table @asis
@item @code{GL_ACCUM}
Obtains R, G, B, and A values from the buffer currently selected for
-reading (see @code{glReadBuffer}). Each component value is divided by
+reading (see @code{glReadBuffer}). Each component value is divided by
@r{2^@var{n}-1}, where @r{@var{n}} is the number of bits allocated to
-each color component in the currently selected buffer. The result is a
+each color component in the currently selected buffer. The result is a
floating-point value in the range @r{[0,1]}, which is multiplied by
@var{value} and added to the corresponding pixel component in the
accumulation buffer, thereby updating the accumulation buffer.
@item @code{GL_RETURN}
Transfers accumulation buffer values to the color buffer or buffers
-currently selected for writing. Each R, G, B, and A component is
+currently selected for writing. Each R, G, B, and A component is
multiplied by @var{value}, then multiplied by @r{2^@var{n}-1}, clamped
to the range @r{[0,2^@var{n}-1]}, and stored in the corresponding
-display buffer cell. The only fragment operations that are applied to
+display buffer cell. The only fragment operations that are applied to
this transfer are pixel ownership, scissor, dithering, and color
writemasks.
@table @asis
@item @var{texture}
-Specifies which texture unit to make active. The number of texture units
-is implementation dependent, but must be at least two. @var{texture}
-must be one of @code{GL_TEXTURE}@r{@var{i}}, where i ranges from 0 to
-the larger of (@code{GL_MAX_TEXTURE_COORDS} - 1) and
-(@code{GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS} - 1). The initial value is
+Specifies which texture unit to make active. The number of texture
+units is implementation dependent, but must be at least two.
+@var{texture} must be one of @code{GL_TEXTURE}@r{@var{i}}, where i
+ranges from 0 to the larger of (@code{GL_MAX_TEXTURE_COORDS} - 1) and
+(@code{GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS} - 1). The initial value is
@code{GL_TEXTURE0}.
@end table
@code{glActiveTexture} selects which texture unit subsequent texture
-state calls will affect. The number of texture units an implementation
+state calls will affect. The number of texture units an implementation
supports is implementation dependent, but must be at least 2.
Vertex arrays are client-side GL resources, which are selected by the
@table @asis
@item @var{func}
-Specifies the alpha comparison function. Symbolic constants
+Specifies the alpha comparison function. Symbolic constants
@code{GL_NEVER}, @code{GL_LESS}, @code{GL_EQUAL}, @code{GL_LEQUAL},
@code{GL_GREATER}, @code{GL_NOTEQUAL}, @code{GL_GEQUAL}, and
-@code{GL_ALWAYS} are accepted. The initial value is @code{GL_ALWAYS}.
+@code{GL_ALWAYS} are accepted. The initial value is @code{GL_ALWAYS}.
@item @var{ref}
Specifies the reference value that incoming alpha values are compared
-to. This value is clamped to the range @r{[0,1]}, where 0 represents the
-lowest possible alpha value and 1 the highest possible value. The
+to. This value is clamped to the range @r{[0,1]}, where 0 represents
+the lowest possible alpha value and 1 the highest possible value. The
initial reference value is 0.
@end table
The alpha test discards fragments depending on the outcome of a
comparison between an incoming fragment's alpha value and a constant
-reference value. @code{glAlphaFunc} specifies the reference value and
-the comparison function. The comparison is performed only if alpha
-testing is enabled. By default, it is not enabled. (See @code{glEnable}
-and @code{glDisable} of @code{GL_ALPHA_TEST}.)
+reference value. @code{glAlphaFunc} specifies the reference value and
+the comparison function. The comparison is performed only if alpha
+testing is enabled. By default, it is not enabled. (See
+@code{glEnable} and @code{glDisable} of @code{GL_ALPHA_TEST}.)
@var{func} and @var{ref} specify the conditions under which the pixel is
-drawn. The incoming alpha value is compared to @var{ref} using the
-function specified by @var{func}. If the value passes the comparison,
+drawn. The incoming alpha value is compared to @var{ref} using the
+function specified by @var{func}. If the value passes the comparison,
the incoming fragment is drawn if it also passes subsequent stencil and
-depth buffer tests. If the value fails the comparison, no change is made
-to the frame buffer at that pixel location. The comparison functions are
-as follows:
+depth buffer tests. If the value fails the comparison, no change is
+made to the frame buffer at that pixel location. The comparison
+functions are as follows:
@table @asis
@item @code{GL_NEVER}
@code{glAlphaFunc} operates on all pixel write operations, including
those resulting from the scan conversion of points, lines, polygons, and
-bitmaps, and from pixel draw and copy operations. @code{glAlphaFunc}
+bitmaps, and from pixel draw and copy operations. @code{glAlphaFunc}
does not affect screen clear operations.
@code{GL_INVALID_ENUM} is generated if @var{func} is not an accepted
@end table
GL establishes a ``working set'' of textures that are resident in
-texture memory. These textures can be bound to a texture target much
+texture memory. These textures can be bound to a texture target much
more efficiently than textures that are not resident.
@code{glAreTexturesResident} queries the texture residence status of the
-@var{n} textures named by the elements of @var{textures}. If all the
+@var{n} textures named by the elements of @var{textures}. If all the
named textures are resident, @code{glAreTexturesResident} returns
-@code{GL_TRUE}, and the contents of @var{residences} are undisturbed. If
+@code{GL_TRUE}, and the contents of @var{residences} are undisturbed. If
not all the named textures are resident, @code{glAreTexturesResident}
returns @code{GL_FALSE}, and detailed status is returned in the @var{n}
-elements of @var{residences}. If an element of @var{residences} is
+elements of @var{residences}. If an element of @var{residences} is
@code{GL_TRUE}, then the texture named by the corresponding element of
@var{textures} is resident.
The residence status of a single bound texture may also be queried by
calling @code{glGetTexParameter} with the @var{target} argument set to
the target to which the texture is bound, and the @var{pname} argument
-set to @code{GL_TEXTURE_RESIDENT}. This is the only way that the
+set to @code{GL_TEXTURE_RESIDENT}. This is the only way that the
residence status of a default texture can be queried.
@code{GL_INVALID_VALUE} is generated if @var{n} is negative.
@code{GL_INVALID_VALUE} is generated if any element in @var{textures} is
-0 or does not name a texture. In that case, the function returns
+0 or does not name a texture. In that case, the function returns
@code{GL_FALSE} and the contents of @var{residences} is indeterminate.
@code{GL_INVALID_OPERATION} is generated if @code{glAreTexturesResident}
@code{glArrayElement} commands are used within
@code{glBegin}/@code{glEnd} pairs to specify vertex and attribute data
-for point, line, and polygon primitives. If @code{GL_VERTEX_ARRAY} is
+for point, line, and polygon primitives. If @code{GL_VERTEX_ARRAY} is
enabled when @code{glArrayElement} is called, a single vertex is drawn,
using vertex and attribute data taken from location @var{i} of the
-enabled arrays. If @code{GL_VERTEX_ARRAY} is not enabled, no drawing
+enabled arrays. If @code{GL_VERTEX_ARRAY} is not enabled, no drawing
occurs but the attributes corresponding to the enabled arrays are
modified.
Use @code{glArrayElement} to construct primitives by indexing vertex
data, rather than by streaming through arrays of data in first-to-last
-order. Because each call specifies only a single vertex, it is possible
+order. Because each call specifies only a single vertex, it is possible
to explicitly specify per-primitive attributes such as a single normal
for each triangle.
Changes made to array data between the execution of @code{glBegin} and
the corresponding execution of @code{glEnd} may affect calls to
@code{glArrayElement} that are made within the same
-@code{glBegin}/@code{glEnd} period in nonsequential ways. That is, a
+@code{glBegin}/@code{glEnd} period in nonsequential ways. That is, a
call to @code{glArrayElement} that precedes a change to array data may
access the changed data, and a call that follows a change to array data
may access original data.
@end table
In order to create an executable, there must be a way to specify the
-list of things that will be linked together. Program objects provide
-this mechanism. Shaders that are to be linked together in a program
+list of things that will be linked together. Program objects provide
+this mechanism. Shaders that are to be linked together in a program
object must first be attached to that program object.
@code{glAttachShader} attaches the shader object specified by
-@var{shader} to the program object specified by @var{program}. This
+@var{shader} to the program object specified by @var{program}. This
indicates that @var{shader} will be included in link operations that
will be performed on @var{program}.
All operations that can be performed on a shader object are valid
-whether or not the shader object is attached to a program object. It is
+whether or not the shader object is attached to a program object. It is
permissible to attach a shader object to a program object before source
code has been loaded into the shader object or before the shader object
-has been compiled. It is permissible to attach multiple shader objects
+has been compiled. It is permissible to attach multiple shader objects
of the same type because each may contain a portion of the complete
-shader. It is also permissible to attach a shader object to more than
-one program object. If a shader object is deleted while it is attached
+shader. It is also permissible to attach a shader object to more than
+one program object. If a shader object is deleted while it is attached
to a program object, it will be flagged for deletion, and deletion will
not occur until @code{glDetachShader} is called to detach it from all
program objects to which it is attached.
@table @asis
@item @var{target}
Specifies the target type of query object established between
-@code{glBeginQuery} and the subsequent @code{glEndQuery}. The symbolic
+@code{glBeginQuery} and the subsequent @code{glEndQuery}. The symbolic
constant must be @code{GL_SAMPLES_PASSED}.
@item @var{id}
@end table
@code{glBeginQuery} and @code{glEndQuery} delimit the boundaries of a
-query object. If a query object with name @var{id} does not yet exist it
-is created.
+query object. If a query object with name @var{id} does not yet exist
+it is created.
When @code{glBeginQuery} is executed, the query object's samples-passed
-counter is reset to 0. Subsequent rendering will increment the counter
-once for every sample that passes the depth test. When @code{glEndQuery}
-is executed, the samples-passed counter is assigned to the query
-object's result value. This value can be queried by calling
+counter is reset to 0. Subsequent rendering will increment the counter
+once for every sample that passes the depth test. When
+@code{glEndQuery} is executed, the samples-passed counter is assigned to
+the query object's result value. This value can be queried by calling
@code{glGetQueryObject} with @var{pname}@code{GL_QUERY_RESULT}.
Querying the @code{GL_QUERY_RESULT} implicitly flushes the GL pipeline
until the rendering delimited by the query object has completed and the
-result is available. @code{GL_QUERY_RESULT_AVAILABLE} can be queried to
+result is available. @code{GL_QUERY_RESULT_AVAILABLE} can be queried to
determine if the result is immediately available or if the rendering is
not yet complete.
@table @asis
@item @var{mode}
Specifies the primitive or primitives that will be created from vertices
-presented between @code{glBegin} and the subsequent @code{glEnd}. Ten
+presented between @code{glBegin} and the subsequent @code{glEnd}. Ten
symbolic constants are accepted: @code{GL_POINTS}, @code{GL_LINES},
@code{GL_LINE_STRIP}, @code{GL_LINE_LOOP}, @code{GL_TRIANGLES},
@code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN}, @code{GL_QUADS},
@end table
@code{glBegin} and @code{glEnd} delimit the vertices that define a
-primitive or a group of like primitives. @code{glBegin} accepts a single
-argument that specifies in which of ten ways the vertices are
-interpreted. Taking @r{@var{n}} as an integer count starting at one, and
-@r{@var{N}} as the total number of vertices specified, the
+primitive or a group of like primitives. @code{glBegin} accepts a
+single argument that specifies in which of ten ways the vertices are
+interpreted. Taking @r{@var{n}} as an integer count starting at one,
+and @r{@var{N}} as the total number of vertices specified, the
interpretations are as follows:
@table @asis
@item @code{GL_POINTS}
-Treats each vertex as a single point. Vertex @r{@var{n}} defines point
-@r{@var{n}}. @r{@var{N}} points are drawn.
+Treats each vertex as a single point. Vertex @r{@var{n}} defines point
+@r{@var{n}}. @r{@var{N}} points are drawn.
@item @code{GL_LINES}
-Treats each pair of vertices as an independent line segment. Vertices
-@r{2@var{n}-1} and @r{2@var{n}} define line @r{@var{n}}. @r{@var{N}/2}
+Treats each pair of vertices as an independent line segment. Vertices
+@r{2@var{n}-1} and @r{2@var{n}} define line @r{@var{n}}. @r{@var{N}/2}
lines are drawn.
@item @code{GL_LINE_STRIP}
Draws a connected group of line segments from the first vertex to the
-last. Vertices @r{@var{n}} and @r{@var{n}+1} define line @r{@var{n}}.
+last. Vertices @r{@var{n}} and @r{@var{n}+1} define line @r{@var{n}}.
@r{@var{N}-1} lines are drawn.
@item @code{GL_LINE_LOOP}
Draws a connected group of line segments from the first vertex to the
-last, then back to the first. Vertices @r{@var{n}} and @r{@var{n}+1}
-define line @r{@var{n}}. The last line, however, is defined by vertices
-@r{@var{N}} and @r{1}. @r{@var{N}} lines are drawn.
+last, then back to the first. Vertices @r{@var{n}} and @r{@var{n}+1}
+define line @r{@var{n}}. The last line, however, is defined by vertices
+@r{@var{N}} and @r{1}. @r{@var{N}} lines are drawn.
@item @code{GL_TRIANGLES}
-Treats each triplet of vertices as an independent triangle. Vertices
+Treats each triplet of vertices as an independent triangle. Vertices
@r{3@var{n}-2}, @r{3@var{n}-1}, and @r{3@var{n}} define triangle
-@r{@var{n}}. @r{@var{N}/3} triangles are drawn.
+@r{@var{n}}. @r{@var{N}/3} triangles are drawn.
@item @code{GL_TRIANGLE_STRIP}
-Draws a connected group of triangles. One triangle is defined for each
-vertex presented after the first two vertices. For odd @r{@var{n}},
+Draws a connected group of triangles. One triangle is defined for each
+vertex presented after the first two vertices. For odd @r{@var{n}},
vertices @r{@var{n}}, @r{@var{n}+1}, and @r{@var{n}+2} define triangle
-@r{@var{n}}. For even @r{@var{n}}, vertices @r{@var{n}+1}, @r{@var{n}},
-and @r{@var{n}+2} define triangle @r{@var{n}}. @r{@var{N}-2} triangles
+@r{@var{n}}. For even @r{@var{n}}, vertices @r{@var{n}+1}, @r{@var{n}},
+and @r{@var{n}+2} define triangle @r{@var{n}}. @r{@var{N}-2} triangles
are drawn.
@item @code{GL_TRIANGLE_FAN}
-Draws a connected group of triangles. One triangle is defined for each
-vertex presented after the first two vertices. Vertices @r{1},
+Draws a connected group of triangles. One triangle is defined for each
+vertex presented after the first two vertices. Vertices @r{1},
@r{@var{n}+1}, and @r{@var{n}+2} define triangle @r{@var{n}}.
@r{@var{N}-2} triangles are drawn.
@item @code{GL_QUADS}
Treats each group of four vertices as an independent quadrilateral.
Vertices @r{4@var{n}-3}, @r{4@var{n}-2}, @r{4@var{n}-1}, and
-@r{4@var{n}} define quadrilateral @r{@var{n}}. @r{@var{N}/4}
+@r{4@var{n}} define quadrilateral @r{@var{n}}. @r{@var{N}/4}
quadrilaterals are drawn.
@item @code{GL_QUAD_STRIP}
-Draws a connected group of quadrilaterals. One quadrilateral is defined
-for each pair of vertices presented after the first pair. Vertices
+Draws a connected group of quadrilaterals. One quadrilateral is defined
+for each pair of vertices presented after the first pair. Vertices
@r{2@var{n}-1}, @r{2@var{n}}, @r{2@var{n}+2}, and @r{2@var{n}+1}
-define quadrilateral @r{@var{n}}. @r{@var{N}/2-1} quadrilaterals are
-drawn. Note that the order in which vertices are used to construct a
+define quadrilateral @r{@var{n}}. @r{@var{N}/2-1} quadrilaterals are
+drawn. Note that the order in which vertices are used to construct a
quadrilateral from strip data is different from that used with
independent data.
@item @code{GL_POLYGON}
-Draws a single, convex polygon. Vertices @r{1} through @r{@var{N}}
+Draws a single, convex polygon. Vertices @r{1} through @r{@var{N}}
define this polygon.
@end table
Only a subset of GL commands can be used between @code{glBegin} and
-@code{glEnd}. The commands are @code{glVertex}, @code{glColor},
+@code{glEnd}. The commands are @code{glVertex}, @code{glColor},
@code{glSecondaryColor}, @code{glIndex}, @code{glNormal},
@code{glFogCoord}, @code{glTexCoord}, @code{glMultiTexCoord},
@code{glVertexAttrib}, @code{glEvalCoord}, @code{glEvalPoint},
-@code{glArrayElement}, @code{glMaterial}, and @code{glEdgeFlag}. Also,
+@code{glArrayElement}, @code{glMaterial}, and @code{glEdgeFlag}. Also,
it is acceptable to use @code{glCallList} or @code{glCallLists} to
-execute display lists that include only the preceding commands. If any
+execute display lists that include only the preceding commands. If any
other GL command is executed between @code{glBegin} and @code{glEnd},
the error flag is set and the command is ignored.
Regardless of the value chosen for @var{mode}, there is no limit to the
number of vertices that can be defined between @code{glBegin} and
-@code{glEnd}. Lines, triangles, quadrilaterals, and polygons that are
-incompletely specified are not drawn. Incomplete specification results
+@code{glEnd}. Lines, triangles, quadrilaterals, and polygons that are
+incompletely specified are not drawn. Incomplete specification results
when either too few vertices are provided to specify even a single
-primitive or when an incorrect multiple of vertices is specified. The
+primitive or when an incorrect multiple of vertices is specified. The
incomplete primitive is ignored; the rest are drawn.
The minimum specification of vertices for each primitive is as follows:
1 for a point, 2 for a line, 3 for a triangle, 4 for a quadrilateral,
-and 3 for a polygon. Modes that require a certain multiple of vertices
+and 3 for a polygon. Modes that require a certain multiple of vertices
are @code{GL_LINES} (2), @code{GL_TRIANGLES} (3), @code{GL_QUADS} (4),
and @code{GL_QUAD_STRIP} (2).
@code{glBindAttribLocation} is used to associate a user-defined
attribute variable in the program object specified by @var{program} with
-a generic vertex attribute index. The name of the user-defined attribute
-variable is passed as a null terminated string in @var{name}. The
-generic vertex attribute index to be bound to this variable is specified
-by @var{index}. When @var{program} is made part of current state, values
-provided via the generic vertex attribute @var{index} will modify the
-value of the user-defined attribute variable specified by @var{name}.
+a generic vertex attribute index. The name of the user-defined
+attribute variable is passed as a null terminated string in @var{name}.
+The generic vertex attribute index to be bound to this variable is
+specified by @var{index}. When @var{program} is made part of current
+state, values provided via the generic vertex attribute @var{index} will
+modify the value of the user-defined attribute variable specified by
+@var{name}.
If @var{name} refers to a matrix attribute variable, @var{index} refers
-to the first column of the matrix. Other matrix columns are then
+to the first column of the matrix. Other matrix columns are then
automatically bound to locations @var{index+1} for a matrix of type
mat2; @var{index+1} and @var{index+2} for a matrix of type mat3; and
@var{index+1}, @var{index+2}, and @var{index+3} for a matrix of type
This command makes it possible for vertex shaders to use descriptive
names for attribute variables rather than generic variables that are
-numbered from 0 to @code{GL_MAX_VERTEX_ATTRIBS} -1. The values sent to
+numbered from 0 to @code{GL_MAX_VERTEX_ATTRIBS} -1. The values sent to
each generic attribute index are part of current state, just like
standard vertex attributes such as color, normal, and vertex position.
If a different program object is made current by calling
Attribute variable name-to-generic attribute index bindings for a
program object can be explicitly assigned at any time by calling
-@code{glBindAttribLocation}. Attribute bindings do not go into effect
-until @code{glLinkProgram} is called. After a program object has been
+@code{glBindAttribLocation}. Attribute bindings do not go into effect
+until @code{glLinkProgram} is called. After a program object has been
linked successfully, the index values for generic attributes remain
fixed (and their values can be queried) until the next link command
occurs.
Applications are not allowed to bind any of the standard OpenGL vertex
attributes using this command, as they are bound automatically when
-needed. Any attribute binding that occurs after the program object has
+needed. Any attribute binding that occurs after the program object has
been linked will not take effect until the next time the program object
is linked.
@table @asis
@item @var{target}
-Specifies the target to which the buffer object is bound. The symbolic
+Specifies the target to which the buffer object is bound. The symbolic
constant must be @code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER} or @code{GL_PIXEL_UNPACK_BUFFER} and
@var{buffer} set to the name of the new buffer object binds the buffer
-object name to the target. When a buffer object is bound to a target,
+object name to the target. When a buffer object is bound to a target,
the previous binding for that target is automatically broken.
-Buffer object names are unsigned integers. The value zero is reserved,
+Buffer object names are unsigned integers. The value zero is reserved,
but there is no default buffer object for each buffer object target.
Instead, @var{buffer} set to zero effectively unbinds any buffer object
previously bound, and restores client memory usage for that buffer
-object target. Buffer object names and the corresponding buffer object
+object target. Buffer object names and the corresponding buffer object
contents are local to the shared display-list space (see
@code{glXCreateContext}) of the current GL rendering context; two
rendering contexts share buffer object names only if they also share
While a non-zero buffer object name is bound, GL operations on the
target to which it is bound affect the bound buffer object, and queries
of the target to which it is bound return state from the bound buffer
-object. While buffer object name zero is bound, as in the initial state,
-attempts to modify or query state on the target to which it is bound
-generates an @code{GL_INVALID_OPERATION} error.
+object. While buffer object name zero is bound, as in the initial
+state, attempts to modify or query state on the target to which it is
+bound generates an @code{GL_INVALID_OPERATION} error.
When vertex array pointer state is changed, for example by a call to
@code{glNormalPointer}, the current buffer object binding
(@code{GL_ARRAY_BUFFER_BINDING}) is copied into the corresponding client
state for the vertex array type being changed, for example
-@code{GL_NORMAL_ARRAY_BUFFER_BINDING}. While a non-zero buffer object is
-bound to the @code{GL_ARRAY_BUFFER} target, the vertex array pointer
+@code{GL_NORMAL_ARRAY_BUFFER_BINDING}. While a non-zero buffer object
+is bound to the @code{GL_ARRAY_BUFFER} target, the vertex array pointer
parameter that is traditionally interpreted as a pointer to client-side
memory is instead interpreted as an offset within the buffer object
measured in basic machine units.
@code{glGetCompressedTexImage}, @code{glGetConvolutionFilter},
@code{glGetHistogram}, @code{glGetMinmax}, @code{glGetPixelMap},
@code{glGetPolygonStipple}, @code{glGetSeparableFilter},
-@code{glGetTexImage}, and @code{glReadPixels}. The pointer parameter
+@code{glGetTexImage}, and @code{glReadPixels}. The pointer parameter
that is traditionally interpreted as a pointer to client-side memory
where the pixels are to be packed is instead interpreted as an offset
within the buffer object measured in basic machine units.
@code{glDrawPixels}, @code{glPixelMap}, @code{glPolygonStipple},
@code{glSeparableFilter2D}, @code{glTexImage1D}, @code{glTexImage2D},
@code{glTexImage3D}, @code{glTexSubImage1D}, @code{glTexSubImage2D}, and
-@code{glTexSubImage3D}. The pointer parameter that is traditionally
+@code{glTexSubImage3D}. The pointer parameter that is traditionally
interpreted as a pointer to client-side memory from which the pixels are
to be unpacked is instead interpreted as an offset within the buffer
object measured in basic machine units.
until the bound buffer object is deleted with @code{glDeleteBuffers}.
Once created, a named buffer object may be re-bound to any target as
-often as needed. However, the GL implementation may make choices about
+often as needed. However, the GL implementation may make choices about
how to optimize the storage of a buffer object based on its initial
binding target.
@table @asis
@item @var{target}
-Specifies the target to which the texture is bound. Must be either
+Specifies the target to which the texture is bound. Must be either
@code{GL_TEXTURE_1D}, @code{GL_TEXTURE_2D}, @code{GL_TEXTURE_3D}, or
@code{GL_TEXTURE_CUBE_MAP}.
@end table
-@code{glBindTexture} lets you create or use a named texture. Calling
+@code{glBindTexture} lets you create or use a named texture. Calling
@code{glBindTexture} with @var{target} set to @code{GL_TEXTURE_1D},
@code{GL_TEXTURE_2D}, @code{GL_TEXTURE_3D} or @code{GL_TEXTURE_CUBE_MAP}
and @var{texture} set to the name of the new texture binds the texture
-name to the target. When a texture is bound to a target, the previous
+name to the target. When a texture is bound to a target, the previous
binding for that target is automatically broken.
-Texture names are unsigned integers. The value zero is reserved to
-represent the default texture for each texture target. Texture names and
-the corresponding texture contents are local to the shared display-list
-space (see @code{glXCreateContext}) of the current GL rendering context;
-two rendering contexts share texture names only if they also share
-display lists.
+Texture names are unsigned integers. The value zero is reserved to
+represent the default texture for each texture target. Texture names
+and the corresponding texture contents are local to the shared
+display-list space (see @code{glXCreateContext}) of the current GL
+rendering context; two rendering contexts share texture names only if
+they also share display lists.
You may use @code{glGenTextures} to generate a set of new texture names.
texture, a texture first bound to @code{GL_TEXTURE_2D} becomes
two-dimensional texture, a texture first bound to @code{GL_TEXTURE_3D}
becomes three-dimensional texture, and a texture first bound to
-@code{GL_TEXTURE_CUBE_MAP} becomes a cube-mapped texture. The state of a
-one-dimensional texture immediately after it is first bound is
+@code{GL_TEXTURE_CUBE_MAP} becomes a cube-mapped texture. The state of
+a one-dimensional texture immediately after it is first bound is
equivalent to the state of the default @code{GL_TEXTURE_1D} at GL
initialization, and similarly for two- and three-dimensional textures
and cube-mapped textures.
While a texture is bound, GL operations on the target to which it is
bound affect the bound texture, and queries of the target to which it is
-bound return state from the bound texture. If texture mapping is active
-on the target to which a texture is bound, the bound texture is used. In
+bound return state from the bound texture. If texture mapping is active
+on the target to which a texture is bound, the bound texture is used. In
effect, the texture targets become aliases for the textures currently
bound to them, and the texture name zero refers to the default textures
that were bound to them at initialization.
texture is deleted with @code{glDeleteTextures}.
Once created, a named texture may be re-bound to its same original
-target as often as needed. It is usually much faster to use
+target as often as needed. It is usually much faster to use
@code{glBindTexture} to bind an existing named texture to one of the
texture targets than it is to reload the texture image using
-@code{glTexImage1D}, @code{glTexImage2D}, or @code{glTexImage3D}. For
+@code{glTexImage1D}, @code{glTexImage2D}, or @code{glTexImage3D}. For
additional control over performance, use @code{glPrioritizeTextures}.
@code{glBindTexture} is included in display lists.
@item @var{xorig}
@itemx @var{yorig}
-Specify the location of the origin in the bitmap image. The origin is
+Specify the location of the origin in the bitmap image. The origin is
measured from the lower left corner of the bitmap, with right and up
being the positive axes.
@end table
-A bitmap is a binary image. When drawn, the bitmap is positioned
+A bitmap is a binary image. When drawn, the bitmap is positioned
relative to the current raster position, and frame buffer pixels
corresponding to 1's in the bitmap are written using the current raster
-color or index. Frame buffer pixels corresponding to 0's in the bitmap
+color or index. Frame buffer pixels corresponding to 0's in the bitmap
are not modified.
-@code{glBitmap} takes seven arguments. The first pair specifies the
-width and height of the bitmap image. The second pair specifies the
+@code{glBitmap} takes seven arguments. The first pair specifies the
+width and height of the bitmap image. The second pair specifies the
location of the bitmap origin relative to the lower left corner of the
-bitmap image. The third pair of arguments specifies @var{x} and @var{y}
+bitmap image. The third pair of arguments specifies @var{x} and @var{y}
offsets to be added to the current raster position after the bitmap has
-been drawn. The final argument is a pointer to the bitmap image itself.
+been drawn. The final argument is a pointer to the bitmap image itself.
If a non-zero named buffer object is bound to the
@code{GL_PIXEL_UNPACK_BUFFER} target (see @code{glBindBuffer}) while a
@code{glDrawPixels} command, with @var{width} and @var{height}
corresponding to the width and height arguments of that command, and
with @var{type} set to @code{GL_BITMAP} and @var{format} set to
-@code{GL_COLOR_INDEX}. Modes specified using @code{glPixelStore} affect
+@code{GL_COLOR_INDEX}. Modes specified using @code{glPixelStore} affect
the interpretation of bitmap image data; modes specified using
@code{glPixelTransfer} do not.
@r{@var{y}_@var{w}=⌊@var{y}_@var{r}-@var{y}_@var{o},⌋}
where @r{(@var{x}_@var{r},@var{y}_@var{r})} is the raster position and
-@r{(@var{x}_@var{o},@var{y}_@var{o})} is the bitmap origin. Fragments
+@r{(@var{x}_@var{o},@var{y}_@var{o})} is the bitmap origin. Fragments
are then generated for each pixel corresponding to a 1 (one) in the
-bitmap image. These fragments are generated using the current raster
+bitmap image. These fragments are generated using the current raster
@var{z} coordinate, color or color index, and current raster texture
-coordinates. They are then treated just as if they had been generated by
-a point, line, or polygon, including texture mapping, fogging, and all
-per-fragment operations such as alpha and depth testing.
+coordinates. They are then treated just as if they had been generated
+by a point, line, or polygon, including texture mapping, fogging, and
+all per-fragment operations such as alpha and depth testing.
After the bitmap has been drawn, the @var{x} and @var{y} coordinates of
the current raster position are offset by @var{xmove} and @var{ymove}.
@end table
The @code{GL_BLEND_COLOR} may be used to calculate the source and
-destination blending factors. The color components are clamped to the
-range @r{[0,1]} before being stored. See @code{glBlendFunc} for a
-complete description of the blending operations. Initially the
+destination blending factors. The color components are clamped to the
+range @r{[0,1]} before being stored. See @code{glBlendFunc} for a
+complete description of the blending operations. Initially the
@code{GL_BLEND_COLOR} is set to (0, 0, 0, 0).
@code{GL_INVALID_OPERATION} is generated if @code{glBlendColor} is
@table @asis
@item @var{modeRGB}
specifies the RGB blend equation, how the red, green, and blue
-components of the source and destination colors are combined. It must be
-@code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
+components of the source and destination colors are combined. It must
+be @code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN}, @code{GL_MAX}.
@item @var{modeAlpha}
specifies the alpha blend equation, how the alpha component of the
-source and destination colors are combined. It must be
+source and destination colors are combined. It must be
@code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN}, @code{GL_MAX}.
The blend equations determines how a new pixel (the ''source'' color) is
combined with a pixel already in the framebuffer (the ''destination''
-color). This function specifies one blend equation for the RGB-color
+color). This function specifies one blend equation for the RGB-color
components and one blend equation for the alpha component.
The blend equations use the source and destination blend factors
are referred to as
@r{(@var{R}_@var{s},@var{G}_@var{s}@var{B}_@var{s}@var{A}_@var{s})} and
@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})},
-respectively. The result color is referred to as
-@r{(@var{R}_@var{r},@var{G}_@var{r}@var{B}_@var{r}@var{A}_@var{r})}. The
+respectively. The result color is referred to as
+@r{(@var{R}_@var{r},@var{G}_@var{r}@var{B}_@var{r}@var{A}_@var{r})}. The
source and destination blend factors are denoted
@r{(@var{s}_@var{R},@var{s}_@var{G}@var{s}_@var{B}@var{s}_@var{A})} and
@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})},
-respectively. For these equations all color components are understood to
-have values in the range @r{[0,1]}.
+respectively. For these equations all color components are understood
+to have values in the range @r{[0,1]}.
@table @asis
@item @strong{Mode}
The @code{GL_MIN} and @code{GL_MAX} equations are useful for
applications that analyze image data (image thresholding against a
-constant color, for example). The @code{GL_FUNC_ADD} equation is useful
+constant color, for example). The @code{GL_FUNC_ADD} equation is useful
for antialiasing and transparency, among other things.
Initially, both the RGB blend equation and the alpha blend equation are
@table @asis
@item @var{mode}
-specifies how source and destination colors are combined. It must be
+specifies how source and destination colors are combined. It must be
@code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN}, @code{GL_MAX}.
The blend equations determine how a new pixel (the ''source'' color) is
combined with a pixel already in the framebuffer (the ''destination''
-color). This function sets both the RGB blend equation and the alpha
+color). This function sets both the RGB blend equation and the alpha
blend equation to a single equation.
These equations use the source and destination blend factors specified
-by either @code{glBlendFunc} or @code{glBlendFuncSeparate}. See
+by either @code{glBlendFunc} or @code{glBlendFuncSeparate}. See
@code{glBlendFunc} or @code{glBlendFuncSeparate} for a description of
the various blend factors.
are referred to as
@r{(@var{R}_@var{s},@var{G}_@var{s}@var{B}_@var{s}@var{A}_@var{s})} and
@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})},
-respectively. The result color is referred to as
-@r{(@var{R}_@var{r},@var{G}_@var{r}@var{B}_@var{r}@var{A}_@var{r})}. The
+respectively. The result color is referred to as
+@r{(@var{R}_@var{r},@var{G}_@var{r}@var{B}_@var{r}@var{A}_@var{r})}. The
source and destination blend factors are denoted
@r{(@var{s}_@var{R},@var{s}_@var{G}@var{s}_@var{B}@var{s}_@var{A})} and
@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})},
-respectively. For these equations all color components are understood to
-have values in the range @r{[0,1]}.
+respectively. For these equations all color components are understood
+to have values in the range @r{[0,1]}.
@table @asis
@item @strong{Mode}
The @code{GL_MIN} and @code{GL_MAX} equations are useful for
applications that analyze image data (image thresholding against a
-constant color, for example). The @code{GL_FUNC_ADD} equation is useful
+constant color, for example). The @code{GL_FUNC_ADD} equation is useful
for antialiasing and transparency, among other things.
Initially, both the RGB blend equation and the alpha blend equation are
@item @var{dstRGB}
Specifies how the red, green, and blue destination blending factors are
-computed. The following symbolic constants are accepted: @code{GL_ZERO},
-@code{GL_ONE}, @code{GL_SRC_COLOR}, @code{GL_ONE_MINUS_SRC_COLOR},
-@code{GL_DST_COLOR}, @code{GL_ONE_MINUS_DST_COLOR}, @code{GL_SRC_ALPHA},
+computed. The following symbolic constants are accepted:
+@code{GL_ZERO}, @code{GL_ONE}, @code{GL_SRC_COLOR},
+@code{GL_ONE_MINUS_SRC_COLOR}, @code{GL_DST_COLOR},
+@code{GL_ONE_MINUS_DST_COLOR}, @code{GL_SRC_ALPHA},
@code{GL_ONE_MINUS_SRC_ALPHA}, @code{GL_DST_ALPHA},
-@code{GL_ONE_MINUS_DST_ALPHA}. @code{GL_CONSTANT_COLOR},
+@code{GL_ONE_MINUS_DST_ALPHA}. @code{GL_CONSTANT_COLOR},
@code{GL_ONE_MINUS_CONSTANT_COLOR}, @code{GL_CONSTANT_ALPHA}, and
-@code{GL_ONE_MINUS_CONSTANT_ALPHA}. The initial value is @code{GL_ZERO}.
+@code{GL_ONE_MINUS_CONSTANT_ALPHA}. The initial value is
+@code{GL_ZERO}.
@item @var{srcAlpha}
-Specified how the alpha source blending factor is computed. The same
-symbolic constants are accepted as for @var{srcRGB}. The initial value
+Specified how the alpha source blending factor is computed. The same
+symbolic constants are accepted as for @var{srcRGB}. The initial value
is @code{GL_ONE}.
@item @var{dstAlpha}
-Specified how the alpha destination blending factor is computed. The
-same symbolic constants are accepted as for @var{dstRGB}. The initial
+Specified how the alpha destination blending factor is computed. The
+same symbolic constants are accepted as for @var{dstRGB}. The initial
value is @code{GL_ZERO}.
@end table
In RGBA mode, pixels can be drawn using a function that blends the
incoming (source) RGBA values with the RGBA values that are already in
-the frame buffer (the destination values). Blending is initially
-disabled. Use @code{glEnable} and @code{glDisable} with argument
+the frame buffer (the destination values). Blending is initially
+disabled. Use @code{glEnable} and @code{glDisable} with argument
@code{GL_BLEND} to enable and disable blending.
@code{glBlendFuncSeparate} defines the operation of blending when it is
-enabled. @var{srcRGB} specifies which method is used to scale the source
-RGB-color components. @var{dstRGB} specifies which method is used to
-scale the destination RGB-color components. Likewise, @var{srcAlpha}
-specifies which method is used to scale the source alpha color
-component, and @var{dstAlpha} specifies which method is used to scale
-the destination alpha component. The possible methods are described in
-the following table. Each method defines four scale factors, one each
-for red, green, blue, and alpha.
+enabled. @var{srcRGB} specifies which method is used to scale the
+source RGB-color components. @var{dstRGB} specifies which method is
+used to scale the destination RGB-color components. Likewise,
+@var{srcAlpha} specifies which method is used to scale the source alpha
+color component, and @var{dstAlpha} specifies which method is used to
+scale the destination alpha component. The possible methods are
+described in the following table. Each method defines four scale
+factors, one each for red, green, blue, and alpha.
In the table and in subsequent equations, source and destination color
components are referred to as
@r{(@var{R}_@var{s},@var{G}_@var{s}@var{B}_@var{s}@var{A}_@var{s})} and
-@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})}. The
+@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})}. The
color specified by @code{glBlendColor} is referred to as
@r{(@var{R}_@var{c},@var{G}_@var{c}@var{B}_@var{c}@var{A}_@var{c})}.
They are understood to have integer values between 0 and
Source and destination scale factors are referred to as
@r{(@var{s}_@var{R},@var{s}_@var{G}@var{s}_@var{B}@var{s}_@var{A})} and
-@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})}. All
+@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})}. All
scale factors have range @r{[0,1]}.
Despite the apparent precision of the above equations, blending
arithmetic is not exactly specified, because blending operates with
-imprecise integer color values. However, a blend factor that should be
+imprecise integer color values. However, a blend factor that should be
equal to 1 is guaranteed not to modify its multiplicand, and a blend
-factor equal to 0 reduces its multiplicand to 0. For example, when
+factor equal to 0 reduces its multiplicand to 0. For example, when
@var{srcRGB} is @code{GL_SRC_ALPHA}, @var{dstRGB} is
@code{GL_ONE_MINUS_SRC_ALPHA}, and @r{@var{A}_@var{s}} is equal to
@r{@var{k}_@var{A}}, the equations reduce to simple replacement:
@table @asis
@item @var{sfactor}
Specifies how the red, green, blue, and alpha source blending factors
-are computed. The following symbolic constants are accepted:
+are computed. The following symbolic constants are accepted:
@code{GL_ZERO}, @code{GL_ONE}, @code{GL_SRC_COLOR},
@code{GL_ONE_MINUS_SRC_COLOR}, @code{GL_DST_COLOR},
@code{GL_ONE_MINUS_DST_COLOR}, @code{GL_SRC_ALPHA},
@item @var{dfactor}
Specifies how the red, green, blue, and alpha destination blending
-factors are computed. The following symbolic constants are accepted:
+factors are computed. The following symbolic constants are accepted:
@code{GL_ZERO}, @code{GL_ONE}, @code{GL_SRC_COLOR},
@code{GL_ONE_MINUS_SRC_COLOR}, @code{GL_DST_COLOR},
@code{GL_ONE_MINUS_DST_COLOR}, @code{GL_SRC_ALPHA},
@code{GL_ONE_MINUS_SRC_ALPHA}, @code{GL_DST_ALPHA},
-@code{GL_ONE_MINUS_DST_ALPHA}. @code{GL_CONSTANT_COLOR},
+@code{GL_ONE_MINUS_DST_ALPHA}. @code{GL_CONSTANT_COLOR},
@code{GL_ONE_MINUS_CONSTANT_COLOR}, @code{GL_CONSTANT_ALPHA}, and
-@code{GL_ONE_MINUS_CONSTANT_ALPHA}. The initial value is @code{GL_ZERO}.
+@code{GL_ONE_MINUS_CONSTANT_ALPHA}. The initial value is
+@code{GL_ZERO}.
@end table
In RGBA mode, pixels can be drawn using a function that blends the
incoming (source) RGBA values with the RGBA values that are already in
-the frame buffer (the destination values). Blending is initially
-disabled. Use @code{glEnable} and @code{glDisable} with argument
+the frame buffer (the destination values). Blending is initially
+disabled. Use @code{glEnable} and @code{glDisable} with argument
@code{GL_BLEND} to enable and disable blending.
@code{glBlendFunc} defines the operation of blending when it is enabled.
@var{sfactor} specifies which method is used to scale the source color
-components. @var{dfactor} specifies which method is used to scale the
-destination color components. The possible methods are described in the
-following table. Each method defines four scale factors, one each for
-red, green, blue, and alpha. In the table and in subsequent equations,
+components. @var{dfactor} specifies which method is used to scale the
+destination color components. The possible methods are described in the
+following table. Each method defines four scale factors, one each for
+red, green, blue, and alpha. In the table and in subsequent equations,
source and destination color components are referred to as
@r{(@var{R}_@var{s},@var{G}_@var{s}@var{B}_@var{s}@var{A}_@var{s})} and
-@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})}. The
+@r{(@var{R}_@var{d},@var{G}_@var{d}@var{B}_@var{d}@var{A}_@var{d})}. The
color specified by @code{glBlendColor} is referred to as
@r{(@var{R}_@var{c},@var{G}_@var{c}@var{B}_@var{c}@var{A}_@var{c})}.
They are understood to have integer values between 0 and
Source and destination scale factors are referred to as
@r{(@var{s}_@var{R},@var{s}_@var{G}@var{s}_@var{B}@var{s}_@var{A})} and
-@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})}. The
+@r{(@var{d}_@var{R},@var{d}_@var{G}@var{d}_@var{B}@var{d}_@var{A})}. The
scale factors described in the table, denoted
@r{(@var{f}_@var{R},@var{f}_@var{G}@var{f}_@var{B}@var{f}_@var{A})},
-represent either source or destination factors. All scale factors have
+represent either source or destination factors. All scale factors have
range @r{[0,1]}.
Despite the apparent precision of the above equations, blending
arithmetic is not exactly specified, because blending operates with
-imprecise integer color values. However, a blend factor that should be
+imprecise integer color values. However, a blend factor that should be
equal to 1 is guaranteed not to modify its multiplicand, and a blend
-factor equal to 0 reduces its multiplicand to 0. For example, when
+factor equal to 0 reduces its multiplicand to 0. For example, when
@var{sfactor} is @code{GL_SRC_ALPHA}, @var{dfactor} is
@code{GL_ONE_MINUS_SRC_ALPHA}, and @r{@var{A}_@var{s}} is equal to
@r{@var{k}_@var{A}}, the equations reduce to simple replacement:
@table @asis
@item @var{target}
-Specifies the target buffer object. The symbolic constant must be
+Specifies the target buffer object. The symbolic constant must be
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
initialization, or @code{NULL} if no data is to be copied.
@item @var{usage}
-Specifies the expected usage pattern of the data store. The symbolic
+Specifies the expected usage pattern of the data store. The symbolic
constant must be @code{GL_STREAM_DRAW}, @code{GL_STREAM_READ},
@code{GL_STREAM_COPY}, @code{GL_STATIC_DRAW}, @code{GL_STATIC_READ},
@code{GL_STATIC_COPY}, @code{GL_DYNAMIC_DRAW}, @code{GL_DYNAMIC_READ},
@end table
@code{glBufferData} creates a new data store for the buffer object
-currently bound to @var{target}. Any pre-existing data store is deleted.
-The new data store is created with the specified @var{size} in bytes and
-@var{usage}. If @var{data} is not @code{NULL}, the data store is
-initialized with data from this pointer. In its initial state, the new
-data store is not mapped, it has a @code{NULL} mapped pointer, and its
-mapped access is @code{GL_READ_WRITE}.
+currently bound to @var{target}. Any pre-existing data store is
+deleted. The new data store is created with the specified @var{size} in
+bytes and @var{usage}. If @var{data} is not @code{NULL}, the data store
+is initialized with data from this pointer. In its initial state, the
+new data store is not mapped, it has a @code{NULL} mapped pointer, and
+its mapped access is @code{GL_READ_WRITE}.
@var{usage} is a hint to the GL implementation as to how a buffer
-object's data store will be accessed. This enables the GL implementation
-to make more intelligent decisions that may significantly impact buffer
-object performance. It does not, however, constrain the actual usage of
-the data store. @var{usage} can be broken down into two parts: first,
-the frequency of access (modification and usage), and second, the nature
-of that access. The frequency of access may be one of these:
+object's data store will be accessed. This enables the GL
+implementation to make more intelligent decisions that may significantly
+impact buffer object performance. It does not, however, constrain the
+actual usage of the data store. @var{usage} can be broken down into two
+parts: first, the frequency of access (modification and usage), and
+second, the nature of that access. The frequency of access may be one
+of these:
@table @asis
@item STREAM
@table @asis
@item @var{target}
-Specifies the target buffer object. The symbolic constant must be
+Specifies the target buffer object. The symbolic constant must be
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@end table
@code{glBufferSubData} redefines some or all of the data store for the
-buffer object currently bound to @var{target}. Data starting at byte
+buffer object currently bound to @var{target}. Data starting at byte
offset @var{offset} and extending for @var{size} bytes is copied to the
-data store from the memory pointed to by @var{data}. An error is thrown
+data store from the memory pointed to by @var{data}. An error is thrown
if @var{offset} and @var{size} together define a range beyond the bounds
of the buffer object's data store.
Specifies the number of display lists to be executed.
@item @var{type}
-Specifies the type of values in @var{lists}. Symbolic constants
+Specifies the type of values in @var{lists}. Symbolic constants
@code{GL_BYTE}, @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT},
@code{GL_UNSIGNED_SHORT}, @code{GL_INT}, @code{GL_UNSIGNED_INT},
@code{GL_FLOAT}, @code{GL_2_BYTES}, @code{GL_3_BYTES}, and
@end table
@code{glCallLists} causes each display list in the list of names passed
-as @var{lists} to be executed. As a result, the commands saved in each
+as @var{lists} to be executed. As a result, the commands saved in each
display list are executed in order, just as if they were called without
-using a display list. Names of display lists that have not been defined
+using a display list. Names of display lists that have not been defined
are ignored.
@code{glCallLists} provides an efficient means for executing more than
-one display list. @var{type} allows lists with various name formats to
-be accepted. The formats are as follows:
+one display list. @var{type} allows lists with various name formats to
+be accepted. The formats are as follows:
@table @asis
@item @code{GL_BYTE}
@var{lists} is treated as an array of four-byte floating-point values.
@item @code{GL_2_BYTES}
-@var{lists} is treated as an array of unsigned bytes. Each pair of bytes
-specifies a single display-list name. The value of the pair is computed
-as 256 times the unsigned value of the first byte plus the unsigned
-value of the second byte.
+@var{lists} is treated as an array of unsigned bytes. Each pair of
+bytes specifies a single display-list name. The value of the pair is
+computed as 256 times the unsigned value of the first byte plus the
+unsigned value of the second byte.
@item @code{GL_3_BYTES}
-@var{lists} is treated as an array of unsigned bytes. Each triplet of
-bytes specifies a single display-list name. The value of the triplet is
+@var{lists} is treated as an array of unsigned bytes. Each triplet of
+bytes specifies a single display-list name. The value of the triplet is
computed as 65536 times the unsigned value of the first byte, plus 256
times the unsigned value of the second byte, plus the unsigned value of
the third byte.
@item @code{GL_4_BYTES}
-@var{lists} is treated as an array of unsigned bytes. Each quadruplet of
-bytes specifies a single display-list name. The value of the quadruplet
-is computed as 16777216 times the unsigned value of the first byte, plus
-65536 times the unsigned value of the second byte, plus 256 times the
-unsigned value of the third byte, plus the unsigned value of the fourth
-byte.
+@var{lists} is treated as an array of unsigned bytes. Each quadruplet
+of bytes specifies a single display-list name. The value of the
+quadruplet is computed as 16777216 times the unsigned value of the first
+byte, plus 65536 times the unsigned value of the second byte, plus 256
+times the unsigned value of the third byte, plus the unsigned value of
+the fourth byte.
@end table
-The list of display-list names is not null-terminated. Rather, @var{n}
+The list of display-list names is not null-terminated. Rather, @var{n}
specifies how many names are to be taken from @var{lists}.
An additional level of indirection is made available with the
added to each display-list name specified in @var{lists} before that
display list is executed.
-@code{glCallLists} can appear inside a display list. To avoid the
+@code{glCallLists} can appear inside a display list. To avoid the
possibility of infinite recursion resulting from display lists calling
one another, a limit is placed on the nesting level of display lists
-during display-list execution. This limit must be at least 64, and it
+during display-list execution. This limit must be at least 64, and it
depends on the implementation.
GL state is not saved and restored across a call to @code{glCallLists}.
Thus, changes made to GL state during the execution of the display lists
-remain after execution is completed. Use @code{glPushAttrib},
+remain after execution is completed. Use @code{glPushAttrib},
@code{glPopAttrib}, @code{glPushMatrix}, and @code{glPopMatrix} to
preserve GL state across @code{glCallLists} calls.
@end table
-@code{glCallList} causes the named display list to be executed. The
+@code{glCallList} causes the named display list to be executed. The
commands saved in the display list are executed in order, just as if
-they were called without using a display list. If @var{list} has not
+they were called without using a display list. If @var{list} has not
been defined as a display list, @code{glCallList} is ignored.
-@code{glCallList} can appear inside a display list. To avoid the
+@code{glCallList} can appear inside a display list. To avoid the
possibility of infinite recursion resulting from display lists calling
one another, a limit is placed on the nesting level of display lists
-during display-list execution. This limit is at least 64, and it depends
-on the implementation.
+during display-list execution. This limit is at least 64, and it
+depends on the implementation.
GL state is not saved and restored across a call to @code{glCallList}.
Thus, changes made to GL state during the execution of a display list
-remain after execution of the display list is completed. Use
+remain after execution of the display list is completed. Use
@code{glPushAttrib}, @code{glPopAttrib}, @code{glPushMatrix}, and
@code{glPopMatrix} to preserve GL state across @code{glCallList} calls.
@itemx @var{blue}
@itemx @var{alpha}
Specify the red, green, blue, and alpha values used when the
-accumulation buffer is cleared. The initial values are all 0.
+accumulation buffer is cleared. The initial values are all 0.
@end table
@itemx @var{blue}
@itemx @var{alpha}
Specify the red, green, blue, and alpha values used when the color
-buffers are cleared. The initial values are all 0.
+buffers are cleared. The initial values are all 0.
@end table
@code{glClearColor} specifies the red, green, blue, and alpha values
-used by @code{glClear} to clear the color buffers. Values specified by
+used by @code{glClear} to clear the color buffers. Values specified by
@code{glClearColor} are clamped to the range @r{[0,1]}.
@code{GL_INVALID_OPERATION} is generated if @code{glClearColor} is
@table @asis
@item @var{depth}
-Specifies the depth value used when the depth buffer is cleared. The
+Specifies the depth value used when the depth buffer is cleared. The
initial value is 1.
@end table
@code{glClearDepth} specifies the depth value used by @code{glClear} to
-clear the depth buffer. Values specified by @code{glClearDepth} are
+clear the depth buffer. Values specified by @code{glClearDepth} are
clamped to the range @r{[0,1]}.
@code{GL_INVALID_OPERATION} is generated if @code{glClearDepth} is
@table @asis
@item @var{c}
-Specifies the index used when the color index buffers are cleared. The
+Specifies the index used when the color index buffers are cleared. The
initial value is 0.
@end table
@code{glClearIndex} specifies the index used by @code{glClear} to clear
-the color index buffers. @var{c} is not clamped. Rather, @var{c} is
+the color index buffers. @var{c} is not clamped. Rather, @var{c} is
converted to a fixed-point value with unspecified precision to the right
-of the binary point. The integer part of this value is then masked with
+of the binary point. The integer part of this value is then masked with
@r{2^@var{m}-1}, where @r{@var{m}} is the number of bits in a color
index stored in the frame buffer.
@table @asis
@item @var{s}
-Specifies the index used when the stencil buffer is cleared. The initial
-value is 0.
+Specifies the index used when the stencil buffer is cleared. The
+initial value is 0.
@end table
@code{glClearStencil} specifies the index used by @code{glClear} to
-clear the stencil buffer. @var{s} is masked with @r{2^@var{m}-1}, where
+clear the stencil buffer. @var{s} is masked with @r{2^@var{m}-1}, where
@r{@var{m}} is the number of bits in the stencil buffer.
@code{GL_INVALID_OPERATION} is generated if @code{glClearStencil} is
@table @asis
@item @var{mask}
-Bitwise OR of masks that indicate the buffers to be cleared. The four
+Bitwise OR of masks that indicate the buffers to be cleared. The four
masks are @code{GL_COLOR_BUFFER_BIT}, @code{GL_DEPTH_BUFFER_BIT},
@code{GL_ACCUM_BUFFER_BIT}, and @code{GL_STENCIL_BUFFER_BIT}.
than one buffer at a time using @code{glDrawBuffer}.
The pixel ownership test, the scissor test, dithering, and the buffer
-writemasks affect the operation of @code{glClear}. The scissor box
-bounds the cleared region. Alpha function, blend function, logical
+writemasks affect the operation of @code{glClear}. The scissor box
+bounds the cleared region. Alpha function, blend function, logical
operation, stenciling, texture mapping, and depth-buffering are ignored
by @code{glClear}.
@table @asis
@item @var{texture}
-Specifies which texture unit to make active. The number of texture units
-is implementation dependent, but must be at least two. @var{texture}
-must be one of @code{GL_TEXTURE}@r{@var{i}}, where i ranges from 0 to
-the value of @code{GL_MAX_TEXTURE_COORDS} - 1, which is an
-implementation-dependent value. The initial value is @code{GL_TEXTURE0}.
+Specifies which texture unit to make active. The number of texture
+units is implementation dependent, but must be at least two.
+@var{texture} must be one of @code{GL_TEXTURE}@r{@var{i}}, where i
+ranges from 0 to the value of @code{GL_MAX_TEXTURE_COORDS} - 1, which is
+an implementation-dependent value. The initial value is
+@code{GL_TEXTURE0}.
@end table
@table @asis
@item @var{plane}
-Specifies which clipping plane is being positioned. Symbolic names of
+Specifies which clipping plane is being positioned. Symbolic names of
the form @code{GL_CLIP_PLANE}@var{i}, where @var{i} is an integer
between 0 and @code{GL_MAX_CLIP_PLANES}@r{-1}, are accepted.
@item @var{equation}
Specifies the address of an array of four double-precision
-floating-point values. These values are interpreted as a plane equation.
+floating-point values. These values are interpreted as a plane
+equation.
@end table
Geometry is always clipped against the boundaries of a six-plane frustum
-in @var{x}, @var{y}, and @var{z}. @code{glClipPlane} allows the
+in @var{x}, @var{y}, and @var{z}. @code{glClipPlane} allows the
specification of additional planes, not necessarily perpendicular to the
@var{x}, @var{y}, or @var{z} axis, against which all geometry is
-clipped. To determine the maximum number of additional clipping planes,
-call @code{glGetIntegerv} with argument @code{GL_MAX_CLIP_PLANES}. All
-implementations support at least six such clipping planes. Because the
+clipped. To determine the maximum number of additional clipping planes,
+call @code{glGetIntegerv} with argument @code{GL_MAX_CLIP_PLANES}. All
+implementations support at least six such clipping planes. Because the
resulting clipping region is the intersection of the defined
half-spaces, it is always convex.
@code{glClipPlane} specifies a half-space using a four-component plane
-equation. When @code{glClipPlane} is called, @var{equation} is
+equation. When @code{glClipPlane} is called, @var{equation} is
transformed by the inverse of the modelview matrix and stored in the
-resulting eye coordinates. Subsequent changes to the modelview matrix
-have no effect on the stored plane-equation components. If the dot
+resulting eye coordinates. Subsequent changes to the modelview matrix
+have no effect on the stored plane-equation components. If the dot
product of the eye coordinates of a vertex with the stored plane
equation components is positive or zero, the vertex is @var{in} with
-respect to that clipping plane. Otherwise, it is @var{out}.
+respect to that clipping plane. Otherwise, it is @var{out}.
To enable and disable clipping planes, call @code{glEnable} and
@code{glDisable} with the argument @code{GL_CLIP_PLANE}@var{i}, where
@itemx @var{blue}
@itemx @var{alpha}
Specify whether red, green, blue, and alpha can or cannot be written
-into the frame buffer. The initial values are all @code{GL_TRUE},
+into the frame buffer. The initial values are all @code{GL_TRUE},
indicating that the color components can be written.
@end table
@code{glColorMask} specifies whether the individual color components in
-the frame buffer can or cannot be written. If @var{red} is
+the frame buffer can or cannot be written. If @var{red} is
@code{GL_FALSE}, for example, no change is made to the red component of
any pixel in any of the color buffers, regardless of the drawing
operation attempted.
-Changes to individual bits of components cannot be controlled. Rather,
+Changes to individual bits of components cannot be controlled. Rather,
changes are either enabled or disabled for entire color components.
@code{GL_INVALID_OPERATION} is generated if @code{glColorMask} is
@table @asis
@item @var{face}
Specifies whether front, back, or both front and back material
-parameters should track the current color. Accepted values are
-@code{GL_FRONT}, @code{GL_BACK}, and @code{GL_FRONT_AND_BACK}. The
+parameters should track the current color. Accepted values are
+@code{GL_FRONT}, @code{GL_BACK}, and @code{GL_FRONT_AND_BACK}. The
initial value is @code{GL_FRONT_AND_BACK}.
@item @var{mode}
Specifies which of several material parameters track the current color.
Accepted values are @code{GL_EMISSION}, @code{GL_AMBIENT},
@code{GL_DIFFUSE}, @code{GL_SPECULAR}, and
-@code{GL_AMBIENT_AND_DIFFUSE}. The initial value is
+@code{GL_AMBIENT_AND_DIFFUSE}. The initial value is
@code{GL_AMBIENT_AND_DIFFUSE}.
@end table
@code{glColorMaterial} specifies which material parameters track the
-current color. When @code{GL_COLOR_MATERIAL} is enabled, the material
+current color. When @code{GL_COLOR_MATERIAL} is enabled, the material
parameter or parameters specified by @var{mode}, of the material or
materials specified by @var{face}, track the current color at all times.
@table @asis
@item @var{size}
-Specifies the number of components per color. Must be 3 or 4. The
+Specifies the number of components per color. Must be 3 or 4. The
initial value is 4.
@item @var{type}
-Specifies the data type of each color component in the array. Symbolic
+Specifies the data type of each color component in the array. Symbolic
constants @code{GL_BYTE}, @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT},
@code{GL_UNSIGNED_SHORT}, @code{GL_INT}, @code{GL_UNSIGNED_INT},
-@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value is
-@code{GL_FLOAT}.
+@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value
+is @code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive colors. If @var{stride} is
-0, the colors are understood to be tightly packed in the array. The
+Specifies the byte offset between consecutive colors. If @var{stride}
+is 0, the colors are understood to be tightly packed in the array. The
initial value is 0.
@item @var{pointer}
Specifies a pointer to the first component of the first color element in
-the array. The initial value is 0.
+the array. The initial value is 0.
@end table
@code{glColorPointer} specifies the location and data format of an array
-of color components to use when rendering. @var{size} specifies the
-number of components per color, and must be 3 or 4. @var{type} specifies
-the data type of each color component, and @var{stride} specifies the
-byte stride from one color to the next, allowing vertices and attributes
-to be packed into a single array or stored in separate arrays.
-(Single-array storage may be more efficient on some implementations; see
-@code{glInterleavedArrays}.)
+of color components to use when rendering. @var{size} specifies the
+number of components per color, and must be 3 or 4. @var{type}
+specifies the data type of each color component, and @var{stride}
+specifies the byte stride from one color to the next, allowing vertices
+and attributes to be packed into a single array or stored in separate
+arrays. (Single-array storage may be more efficient on some
+implementations; see @code{glInterleavedArrays}.)
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a color array is specified,
@var{pointer} is treated as a byte offset into the buffer object's data
-store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
+store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
is saved as color vertex array client-side state
(@code{GL_COLOR_ARRAY_BUFFER_BINDING}).
The number of table entries to replace.
@item @var{format}
-The format of the pixel data in @var{data}. The allowable values are
+The format of the pixel data in @var{data}. The allowable values are
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB},
@code{GL_BGR}, @code{GL_RGBA}, and @code{GL_BGRA}.
@item @var{type}
-The type of the pixel data in @var{data}. The allowable values are
+The type of the pixel data in @var{data}. The allowable values are
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_UNSIGNED_SHORT},
@code{GL_SHORT}, @code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
@end table
@code{glColorSubTable} is used to respecify a contiguous portion of a
-color table previously defined using @code{glColorTable}. The pixels
+color table previously defined using @code{glColorTable}. The pixels
referenced by @var{data} replace the portion of the existing table from
-indices @var{start} to @r{@var{start}+@var{count}-1}, inclusive. This
+indices @var{start} to @r{@var{start}+@var{count}-1}, inclusive. This
region may not include any entries outside the range of the color table
-as it was originally specified. It is not an error to specify a
+as it was originally specified. It is not an error to specify a
subtexture with width of 0, but such a specification has no effect.
If a non-zero named buffer object is bound to the
@table @asis
@item @var{target}
-The target color table. Must be @code{GL_COLOR_TABLE},
+The target color table. Must be @code{GL_COLOR_TABLE},
@code{GL_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE}.
@item @var{pname}
-The symbolic name of a texture color lookup table parameter. Must be one
-of @code{GL_COLOR_TABLE_SCALE} or @code{GL_COLOR_TABLE_BIAS}.
+The symbolic name of a texture color lookup table parameter. Must be
+one of @code{GL_COLOR_TABLE_SCALE} or @code{GL_COLOR_TABLE_BIAS}.
@item @var{params}
A pointer to an array where the values of the parameters are stored.
@code{glColorTableParameter} is used to specify the scale factors and
bias terms applied to color components when they are loaded into a color
-table. @var{target} indicates which color table the scale and bias terms
-apply to; it must be set to @code{GL_COLOR_TABLE},
+table. @var{target} indicates which color table the scale and bias
+terms apply to; it must be set to @code{GL_COLOR_TABLE},
@code{GL_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE}.
@var{pname} must be @code{GL_COLOR_TABLE_SCALE} to set the scale
-factors. In this case, @var{params} points to an array of four values,
+factors. In this case, @var{params} points to an array of four values,
which are the scale factors for red, green, blue, and alpha, in that
order.
-@var{pname} must be @code{GL_COLOR_TABLE_BIAS} to set the bias terms. In
+@var{pname} must be @code{GL_COLOR_TABLE_BIAS} to set the bias terms. In
this case, @var{params} points to an array of four values, which are the
bias terms for red, green, blue, and alpha, in that order.
@code{GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE}.
@item @var{internalformat}
-The internal format of the color table. The allowable values are
+The internal format of the color table. The allowable values are
@code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_LUMINANCE}, @code{GL_LUMINANCE4},
@code{GL_LUMINANCE8}, @code{GL_LUMINANCE12}, @code{GL_LUMINANCE16},
The number of entries in the color lookup table specified by @var{data}.
@item @var{format}
-The format of the pixel data in @var{data}. The allowable values are
+The format of the pixel data in @var{data}. The allowable values are
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB},
@code{GL_BGR}, @code{GL_RGBA}, and @code{GL_BGRA}.
@item @var{type}
-The type of the pixel data in @var{data}. The allowable values are
+The type of the pixel data in @var{data}. The allowable values are
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_UNSIGNED_SHORT},
@code{GL_SHORT}, @code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
@code{glColorTable} may be used in two ways: to test the actual size and
color resolution of a lookup table given a particular set of parameters,
-or to load the contents of a color lookup table. Use the targets
+or to load the contents of a color lookup table. Use the targets
@code{GL_PROXY_*} for the first case and the other targets for the
second case.
If @var{target} is @code{GL_COLOR_TABLE},
@code{GL_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE}, @code{glColorTable} builds a
-color lookup table from an array of pixels. The pixel array specified by
-@var{width}, @var{format}, @var{type}, and @var{data} is extracted from
-memory and processed just as if @code{glDrawPixels} were called, but
-processing stops after the final expansion to RGBA is completed.
+color lookup table from an array of pixels. The pixel array specified
+by @var{width}, @var{format}, @var{type}, and @var{data} is extracted
+from memory and processed just as if @code{glDrawPixels} were called,
+but processing stops after the final expansion to RGBA is completed.
The four scale parameters and the four bias parameters that are defined
for the table are then used to scale and bias the R, G, B, and A
-components of each pixel. (Use @code{glColorTableParameter} to set these
-scale and bias parameters.)
+components of each pixel. (Use @code{glColorTableParameter} to set
+these scale and bias parameters.)
-Next, the R, G, B, and A values are clamped to the range @r{[0,1]}. Each
+Next, the R, G, B, and A values are clamped to the range @r{[0,1]}. Each
pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
@end table
Finally, the red, green, blue, alpha, luminance, and/or intensity
-components of the resulting pixels are stored in the color table. They
+components of the resulting pixels are stored in the color table. They
form a one-dimensional table with indices in the range
@r{[0,@var{width}-1]}.
@code{GL_COLOR_TABLE_RED_SIZE}, @code{GL_COLOR_TABLE_GREEN_SIZE},
@code{GL_COLOR_TABLE_BLUE_SIZE}, @code{GL_COLOR_TABLE_ALPHA_SIZE},
@code{GL_COLOR_TABLE_LUMINANCE_SIZE}, and
-@code{GL_COLOR_TABLE_INTENSITY_SIZE}. There is no effect on the image or
-state of any actual color table. If the specified color table is too
+@code{GL_COLOR_TABLE_INTENSITY_SIZE}. There is no effect on the image
+or state of any actual color table. If the specified color table is too
large to be supported, then all the proxy state variables listed above
-are set to zero. Otherwise, the color table could be supported by
+are set to zero. Otherwise, the color table could be supported by
@code{glColorTable} using the corresponding non-proxy target, and the
proxy state variables are set as if that target were being defined.
The proxy state variables can be retrieved by calling
-@code{glGetColorTableParameter} with a target of @code{GL_PROXY_*}. This
+@code{glGetColorTableParameter} with a target of @code{GL_PROXY_*}. This
allows the application to decide if a particular @code{glColorTable}
command would succeed, and to determine what the resulting color table
attributes would be.
pixel group, based on the internal format of the table.
Each pixel group has color components (R, G, B, A) that are in the range
-@r{[0.0,1.0]}. The color components are rescaled to the size of the
-color lookup table to form an index. Then a subset of the components
+@r{[0.0,1.0]}. The color components are rescaled to the size of the
+color lookup table to form an index. Then a subset of the components
based on the internal format of the table are replaced by the table
-entry selected by that index. If the color components and contents of
+entry selected by that index. If the color components and contents of
the table are represented as follows:
When @code{GL_COLOR_TABLE} is enabled, the colors resulting from the
pixel map operation (if it is enabled) are mapped by the color lookup
-table before being passed to the convolution operation. The colors
+table before being passed to the convolution operation. The colors
resulting from the convolution operation are modified by the post
convolution color lookup table when
-@code{GL_POST_CONVOLUTION_COLOR_TABLE} is enabled. These modified colors
-are then sent to the color matrix operation. Finally, if
+@code{GL_POST_CONVOLUTION_COLOR_TABLE} is enabled. These modified
+colors are then sent to the color matrix operation. Finally, if
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE} is enabled, the colors resulting
from the color matrix operation are mapped by the post color matrix
color lookup table before being used by the histogram operation.
Specify new red, green, and blue values for the current color.
@item @var{alpha}
-Specifies a new alpha value for the current color. Included only in the
+Specifies a new alpha value for the current color. Included only in the
four-argument @code{glColor4} commands.
@end table
The GL stores both a current single-valued color index and a current
-four-valued RGBA color. @code{glColor} sets a new four-valued RGBA
-color. @code{glColor} has two major variants: @code{glColor3} and
-@code{glColor4}. @code{glColor3} variants specify new red, green, and
+four-valued RGBA color. @code{glColor} sets a new four-valued RGBA
+color. @code{glColor} has two major variants: @code{glColor3} and
+@code{glColor4}. @code{glColor3} variants specify new red, green, and
blue values explicitly and set the current alpha value to 1.0 (full
-intensity) implicitly. @code{glColor4} variants specify all four color
+intensity) implicitly. @code{glColor4} variants specify all four color
components explicitly.
@code{glColor3b}, @code{glColor4b}, @code{glColor3s}, @code{glColor4s},
@code{glColor3i}, and @code{glColor4i} take three or four signed byte,
-short, or long integers as arguments. When @strong{v} is appended to the
-name, the color commands can take a pointer to an array of such values.
+short, or long integers as arguments. When @strong{v} is appended to
+the name, the color commands can take a pointer to an array of such
+values.
Current color values are stored in floating-point format, with
-unspecified mantissa and exponent sizes. Unsigned integer color
+unspecified mantissa and exponent sizes. Unsigned integer color
components, when specified, are linearly mapped to floating-point values
such that the largest representable value maps to 1.0 (full intensity),
-and 0 maps to 0.0 (zero intensity). Signed integer color components,
+and 0 maps to 0.0 (zero intensity). Signed integer color components,
when specified, are linearly mapped to floating-point values such that
the most positive representable value maps to 1.0, and the most negative
-representable value maps to @r{-1.0}. (Note that this mapping does not
+representable value maps to @r{-1.0}. (Note that this mapping does not
convert 0 precisely to 0.0.) Floating-point values are mapped directly.
Neither floating-point nor signed integer values are clamped to the
-range @r{[0,1]} before the current color is updated. However, color
+range @r{[0,1]} before the current color is updated. However, color
components are clamped to this range before they are interpolated or
written into a color buffer.
stored in the shader object specified by @var{shader}.
The compilation status will be stored as part of the shader object's
-state. This value will be set to @code{GL_TRUE} if the shader was
+state. This value will be set to @code{GL_TRUE} if the shader was
compiled without errors and is ready for use, and @code{GL_FALSE}
-otherwise. It can be queried by calling @code{glGetShader} with
+otherwise. It can be queried by calling @code{glGetShader} with
arguments @var{shader} and @code{GL_COMPILE_STATUS}.
Compilation of a shader can fail for a number of reasons as specified by
-the OpenGL Shading Language Specification. Whether or not the
+the OpenGL Shading Language Specification. Whether or not the
compilation was successful, information about the compilation can be
obtained from the shader object's information log by calling
@code{glGetShaderInfoLog}.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D} or
+Specifies the target texture. Must be @code{GL_TEXTURE_1D} or
@code{GL_PROXY_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalformat}
@var{data}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support texture images that are at least 64 texels wide.
The height of the 1D texture image is 1.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{imageSize}
Specifies the number of unsigned bytes of image data starting at the
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable one-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_1D}.
for consistency, and checked against the implementation's capabilities.
If the implementation cannot handle a texture of the requested texture
size, it sets all of the image state to 0, but does not generate an
-error (see @code{glGetError}). To query for an entire mipmap array, use
+error (see @code{glGetError}). To query for an entire mipmap array, use
an image array level greater than or equal to 1.
@var{internalformat} must be extension-specified compressed-texture
-format. When a texture is loaded with @code{glTexImage1D} using a
+format. When a texture is loaded with @code{glTexImage1D} using a
generic compressed texture format (e.g., @code{GL_COMPRESSED_RGB}) the
-GL selects from one of its extensions supporting compressed textures. In
+GL selects from one of its extensions supporting compressed textures. In
order to load the compressed texture image using
@code{glCompressedTexImage1D}, query the compressed texture image's size
and format using @code{glGetTexLevelParameter}.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_PROXY_TEXTURE_2D}, @code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_PROXY_TEXTURE_CUBE_MAP}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalformat}
@var{data}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support 2D texture images that are at least 64 texels
wide and cube-mapped texture images that are at least 16 texels wide.
Specifies the height of the texture image including the border if any.
If the GL version does not support non-power-of-two sizes, this value
must be Must be @r{2^@var{n}+2(@var{border},)} for some integer
-@r{@var{n}}. All implementations support 2D texture images that are at
+@r{@var{n}}. All implementations support 2D texture images that are at
least 64 texels high and cube-mapped texture images that are at least 16
texels high.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{imageSize}
Specifies the number of unsigned bytes of image data starting at the
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable two-dimensional texturing, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
+@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
disable texturing using cube-mapped textures, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_CUBE_MAP}.
for consistency, and checked against the implementation's capabilities.
If the implementation cannot handle a texture of the requested texture
size, it sets all of the image state to 0, but does not generate an
-error (see @code{glGetError}). To query for an entire mipmap array, use
+error (see @code{glGetError}). To query for an entire mipmap array, use
an image array level greater than or equal to 1.
@var{internalformat} must be an extension-specified compressed-texture
-format. When a texture is loaded with @code{glTexImage2D} using a
+format. When a texture is loaded with @code{glTexImage2D} using a
generic compressed texture format (e.g., @code{GL_COMPRESSED_RGB}), the
-GL selects from one of its extensions supporting compressed textures. In
+GL selects from one of its extensions supporting compressed textures. In
order to load the compressed texture image using
@code{glCompressedTexImage2D}, query the compressed texture image's size
and format using @code{glGetTexLevelParameter}.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_3D} or
+Specifies the target texture. Must be @code{GL_TEXTURE_3D} or
@code{GL_PROXY_TEXTURE_3D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalformat}
@var{data}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support 3D texture images that are at least 16 texels
wide.
texels high.
@item @var{depth}
-Specifies the depth of the texture image including the border if any. If
+Specifies the depth of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support 3D texture images that are at least 16 texels
deep.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{imageSize}
Specifies the number of unsigned bytes of image data starting at the
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable three-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_3D}.
for consistency, and checked against the implementation's capabilities.
If the implementation cannot handle a texture of the requested texture
size, it sets all of the image state to 0, but does not generate an
-error (see @code{glGetError}). To query for an entire mipmap array, use
+error (see @code{glGetError}). To query for an entire mipmap array, use
an image array level greater than or equal to 1.
@var{internalformat} must be an extension-specified compressed-texture
-format. When a texture is loaded with @code{glTexImage2D} using a
+format. When a texture is loaded with @code{glTexImage2D} using a
generic compressed texture format (e.g., @code{GL_COMPRESSED_RGB}), the
-GL selects from one of its extensions supporting compressed textures. In
+GL selects from one of its extensions supporting compressed textures. In
order to load the compressed texture image using
@code{glCompressedTexImage3D}, query the compressed texture image's size
and format using @code{glGetTexLevelParameter}.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable one-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_1D}.
@code{glCompressedTexSubImage1D} redefines a contiguous subregion of an
-existing one-dimensional texture image. The texels referenced by
+existing one-dimensional texture image. The texels referenced by
@var{data} replace the portion of the existing texture array with x
indices @var{xoffset} and @r{@var{xoffset}+@var{width}-1}, inclusive.
This region may not include any texels outside the range of the texture
-array as it was originally specified. It is not an error to specify a
+array as it was originally specified. It is not an error to specify a
subtexture with width of 0, but such a specification has no effect.
@var{format} must be an extension-specified compressed-texture format.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable two-dimensional texturing, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
+@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
disable texturing using cube-mapped texture, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_CUBE_MAP}.
@code{glCompressedTexSubImage2D} redefines a contiguous subregion of an
-existing two-dimensional texture image. The texels referenced by
+existing two-dimensional texture image. The texels referenced by
@var{data} replace the portion of the existing texture array with x
indices @var{xoffset} and @r{@var{xoffset}+@var{width}-1}, and the y
indices @var{yoffset} and @r{@var{yoffset}+@var{height}-1}, inclusive.
This region may not include any texels outside the range of the texture
-array as it was originally specified. It is not an error to specify a
+array as it was originally specified. It is not an error to specify a
subtexture with width of 0, but such a specification has no effect.
@var{format} must be an extension-specified compressed-texture format.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_3D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_3D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable three-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_3D}.
@code{glCompressedTexSubImage3D} redefines a contiguous subregion of an
-existing three-dimensional texture image. The texels referenced by
+existing three-dimensional texture image. The texels referenced by
@var{data} replace the portion of the existing texture array with x
indices @var{xoffset} and @r{@var{xoffset}+@var{width}-1}, and the y
indices @var{yoffset} and @r{@var{yoffset}+@var{height}-1}, and the z
indices @var{zoffset} and @r{@var{zoffset}+@var{depth}-1}, inclusive.
This region may not include any texels outside the range of the texture
-array as it was originally specified. It is not an error to specify a
+array as it was originally specified. It is not an error to specify a
subtexture with width of 0, but such a specification has no effect.
@var{format} must be an extension-specified compressed-texture format.
Must be @code{GL_CONVOLUTION_1D}.
@item @var{internalformat}
-The internal format of the convolution filter kernel. The allowable
+The internal format of the convolution filter kernel. The allowable
values are @code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8},
@code{GL_ALPHA12}, @code{GL_ALPHA16}, @code{GL_LUMINANCE},
@code{GL_LUMINANCE4}, @code{GL_LUMINANCE8}, @code{GL_LUMINANCE12},
The width of the pixel array referenced by @var{data}.
@item @var{format}
-The format of the pixel data in @var{data}. The allowable values are
+The format of the pixel data in @var{data}. The allowable values are
@code{GL_ALPHA}, @code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA},
@code{GL_INTENSITY}, @code{GL_RGB}, and @code{GL_RGBA}.
@item @var{type}
-The type of the pixel data in @var{data}. Symbolic constants
+The type of the pixel data in @var{data}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
The R, G, B, and A components of each pixel are next scaled by the four
1D @code{GL_CONVOLUTION_FILTER_SCALE} parameters and biased by the four
-1D @code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
+1D @code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
parameters are set by @code{glConvolutionParameter} using the
@code{GL_CONVOLUTION_1D} target and the names
@code{GL_CONVOLUTION_FILTER_SCALE} and
-@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are vectors
-of four values that are applied to red, green, blue, and alpha, in that
-order.) The R, G, B, and A values are not clamped to [0,1] at any time
-during this process.
+@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are
+vectors of four values that are applied to red, green, blue, and alpha,
+in that order.) The R, G, B, and A values are not clamped to [0,1] at
+any time during this process.
Each pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
The red, green, blue, alpha, luminance, and/or intensity components of
the resulting pixels are stored in floating-point rather than integer
-format. They form a one-dimensional filter kernel image indexed with
+format. They form a one-dimensional filter kernel image indexed with
coordinate @var{i} such that @var{i} starts at 0 and increases from left
-to right. Kernel location @var{i} is derived from the @var{i}th pixel,
+to right. Kernel location @var{i} is derived from the @var{i}th pixel,
counting from 0.
Note that after a convolution is performed, the resulting color
@code{GL_POST_CONVOLUTION_c_SCALE} parameters and biased by their
corresponding @code{GL_POST_CONVOLUTION_c_BIAS} parameters (where
@var{c} takes on the values @strong{RED}, @strong{GREEN}, @strong{BLUE},
-and @strong{ALPHA}). These parameters are set by @code{glPixelTransfer}.
+and @strong{ALPHA}). These parameters are set by
+@code{glPixelTransfer}.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_CONVOLUTION_1D}.
allowable values.
@code{GL_INVALID_VALUE} is generated if @var{width} is less than zero or
-greater than the maximum supported value. This value may be queried with
-@code{glGetConvolutionParameter} using target @code{GL_CONVOLUTION_1D}
-and name @code{GL_MAX_CONVOLUTION_WIDTH}.
+greater than the maximum supported value. This value may be queried
+with @code{glGetConvolutionParameter} using target
+@code{GL_CONVOLUTION_1D} and name @code{GL_MAX_CONVOLUTION_WIDTH}.
@code{GL_INVALID_OPERATION} is generated if @var{format} is one of
@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
Must be @code{GL_CONVOLUTION_2D}.
@item @var{internalformat}
-The internal format of the convolution filter kernel. The allowable
+The internal format of the convolution filter kernel. The allowable
values are @code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8},
@code{GL_ALPHA12}, @code{GL_ALPHA16}, @code{GL_LUMINANCE},
@code{GL_LUMINANCE4}, @code{GL_LUMINANCE8}, @code{GL_LUMINANCE12},
The height of the pixel array referenced by @var{data}.
@item @var{format}
-The format of the pixel data in @var{data}. The allowable values are
+The format of the pixel data in @var{data}. The allowable values are
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA}, @code{GL_BGRA},
@code{GL_LUMINANCE}, and @code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-The type of the pixel data in @var{data}. Symbolic constants
+The type of the pixel data in @var{data}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
The R, G, B, and A components of each pixel are next scaled by the four
2D @code{GL_CONVOLUTION_FILTER_SCALE} parameters and biased by the four
-2D @code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
+2D @code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
parameters are set by @code{glConvolutionParameter} using the
@code{GL_CONVOLUTION_2D} target and the names
@code{GL_CONVOLUTION_FILTER_SCALE} and
-@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are vectors
-of four values that are applied to red, green, blue, and alpha, in that
-order.) The R, G, B, and A values are not clamped to [0,1] at any time
-during this process.
+@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are
+vectors of four values that are applied to red, green, blue, and alpha,
+in that order.) The R, G, B, and A values are not clamped to [0,1] at
+any time during this process.
Each pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
The red, green, blue, alpha, luminance, and/or intensity components of
the resulting pixels are stored in floating-point rather than integer
-format. They form a two-dimensional filter kernel image indexed with
+format. They form a two-dimensional filter kernel image indexed with
coordinates @var{i} and @var{j} such that @var{i} starts at zero and
increases from left to right, and @var{j} starts at zero and increases
-from bottom to top. Kernel location @var{i,j} is derived from the
+from bottom to top. Kernel location @var{i,j} is derived from the
@var{N}th pixel, where @var{N} is @var{i}+@var{j}*@var{width}.
Note that after a convolution is performed, the resulting color
@code{GL_POST_CONVOLUTION_c_SCALE} parameters and biased by their
corresponding @code{GL_POST_CONVOLUTION_c_BIAS} parameters (where
@var{c} takes on the values @strong{RED}, @strong{GREEN}, @strong{BLUE},
-and @strong{ALPHA}). These parameters are set by @code{glPixelTransfer}.
+and @strong{ALPHA}). These parameters are set by
+@code{glPixelTransfer}.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_CONVOLUTION_2D}.
allowable values.
@code{GL_INVALID_VALUE} is generated if @var{width} is less than zero or
-greater than the maximum supported value. This value may be queried with
-@code{glGetConvolutionParameter} using target @code{GL_CONVOLUTION_2D}
-and name @code{GL_MAX_CONVOLUTION_WIDTH}.
+greater than the maximum supported value. This value may be queried
+with @code{glGetConvolutionParameter} using target
+@code{GL_CONVOLUTION_2D} and name @code{GL_MAX_CONVOLUTION_WIDTH}.
@code{GL_INVALID_VALUE} is generated if @var{height} is less than zero
-or greater than the maximum supported value. This value may be queried
+or greater than the maximum supported value. This value may be queried
with @code{glGetConvolutionParameter} using target
@code{GL_CONVOLUTION_2D} and name @code{GL_MAX_CONVOLUTION_HEIGHT}.
@table @asis
@item @var{target}
-The target for the convolution parameter. Must be one of
+The target for the convolution parameter. Must be one of
@code{GL_CONVOLUTION_1D}, @code{GL_CONVOLUTION_2D}, or
@code{GL_SEPARABLE_2D}.
@item @var{pname}
-The parameter to be set. Must be @code{GL_CONVOLUTION_BORDER_MODE}.
+The parameter to be set. Must be @code{GL_CONVOLUTION_BORDER_MODE}.
@item @var{params}
-The parameter value. Must be one of @code{GL_REDUCE},
+The parameter value. Must be one of @code{GL_REDUCE},
@code{GL_CONSTANT_BORDER}, @code{GL_REPLICATE_BORDER}.
@code{GL_CONVOLUTION_FILTER_SCALE} and @code{GL_CONVOLUTION_FILTER_BIAS}
affect the definition of the convolution filter kernel; see
@code{glConvolutionFilter1D}, @code{glConvolutionFilter2D}, and
-@code{glSeparableFilter2D} for details. In these cases, @var{params}v is
-an array of four values to be applied to red, green, blue, and alpha
-values, respectively. The initial value for
+@code{glSeparableFilter2D} for details. In these cases, @var{params}v
+is an array of four values to be applied to red, green, blue, and alpha
+values, respectively. The initial value for
@code{GL_CONVOLUTION_FILTER_SCALE} is (1, 1, 1, 1), and the initial
value for @code{GL_CONVOLUTION_FILTER_BIAS} is (0, 0, 0, 0).
A @var{pname} value of @code{GL_CONVOLUTION_BORDER_MODE} controls the
-convolution border mode. The accepted modes are:
+convolution border mode. The accepted modes are:
@table @asis
@item @code{GL_REDUCE}
If the filter width is @r{@var{Wf}} and height is @r{@var{Hf}}, and the
source image width is @r{@var{Ws}} and height is @r{@var{Hs}}, then the
convolved image width will be @r{@var{Ws}-@var{Wf}+1} and height will be
-@r{@var{Hs}-@var{Hf}+1}. (If this reduction would generate an image with
-zero or negative width and/or height, the output is simply null, with no
-error generated.) The coordinates of the image resulting from
+@r{@var{Hs}-@var{Hf}+1}. (If this reduction would generate an image
+with zero or negative width and/or height, the output is simply null,
+with no error generated.) The coordinates of the image resulting from
convolution are zero through @r{@var{Ws}-@var{Wf}} in width and zero
through @r{@var{Hs}-@var{Hf}} in height.
@end table
@code{glCopyColorSubTable} is used to respecify a contiguous portion of
-a color table previously defined using @code{glColorTable}. The pixels
+a color table previously defined using @code{glColorTable}. The pixels
copied from the framebuffer replace the portion of the existing table
-from indices @var{start} to @r{@var{start}+@var{x}-1}, inclusive. This
+from indices @var{start} to @r{@var{start}+@var{x}-1}, inclusive. This
region may not include any entries outside the range of the color table,
-as was originally specified. It is not an error to specify a subtexture
+as was originally specified. It is not an error to specify a subtexture
with width of 0, but such a specification has no effect.
@code{GL_INVALID_VALUE} is generated if @var{target} is not a previously
@table @asis
@item @var{target}
-The color table target. Must be @code{GL_COLOR_TABLE},
+The color table target. Must be @code{GL_COLOR_TABLE},
@code{GL_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE}.
@item @var{internalformat}
-The internal storage format of the texture image. Must be one of the
+The internal storage format of the texture image. Must be one of the
following symbolic constants: @code{GL_ALPHA}, @code{GL_ALPHA4},
@code{GL_ALPHA8}, @code{GL_ALPHA12}, @code{GL_ALPHA16},
@code{GL_LUMINANCE}, @code{GL_LUMINANCE4}, @code{GL_LUMINANCE8},
The screen-aligned pixel rectangle with lower-left corner at (@var{x},\
@var{y}) having width @var{width} and height 1 is loaded into the color
-table. If any pixels within this region are outside the window that is
+table. If any pixels within this region are outside the window that is
associated with the GL context, the values obtained for those pixels are
undefined.
The four scale parameters and the four bias parameters that are defined
for the table are then used to scale and bias the R, G, B, and A
-components of each pixel. The scale and bias parameters are set by
+components of each pixel. The scale and bias parameters are set by
calling @code{glColorTableParameter}.
-Next, the R, G, B, and A values are clamped to the range @r{[0,1]}. Each
+Next, the R, G, B, and A values are clamped to the range @r{[0,1]}. Each
pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
@end table
Finally, the red, green, blue, alpha, luminance, and/or intensity
-components of the resulting pixels are stored in the color table. They
+components of the resulting pixels are stored in the color table. They
form a one-dimensional table with indices in the range
@r{[0,@var{width}-1]}.
Must be @code{GL_CONVOLUTION_1D}.
@item @var{internalformat}
-The internal format of the convolution filter kernel. The allowable
+The internal format of the convolution filter kernel. The allowable
values are @code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8},
@code{GL_ALPHA12}, @code{GL_ALPHA16}, @code{GL_LUMINANCE},
@code{GL_LUMINANCE4}, @code{GL_LUMINANCE8}, @code{GL_LUMINANCE12},
The screen-aligned pixel rectangle with lower-left corner at (@var{x},\
@var{y}), width @var{width} and height 1 is used to define the
-convolution filter. If any pixels within this region are outside the
+convolution filter. If any pixels within this region are outside the
window that is associated with the GL context, the values obtained for
those pixels are undefined.
The pixels in the rectangle are processed exactly as if
@code{glReadPixels} had been called with @var{format} set to RGBA, but
-the process stops just before final conversion. The R, G, B, and A
+the process stops just before final conversion. The R, G, B, and A
components of each pixel are next scaled by the four 1D
@code{GL_CONVOLUTION_FILTER_SCALE} parameters and biased by the four 1D
-@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
+@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
parameters are set by @code{glConvolutionParameter} using the
@code{GL_CONVOLUTION_1D} target and the names
@code{GL_CONVOLUTION_FILTER_SCALE} and
-@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are vectors
-of four values that are applied to red, green, blue, and alpha, in that
-order.) The R, G, B, and A values are not clamped to [0,1] at any time
-during this process.
+@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are
+vectors of four values that are applied to red, green, blue, and alpha,
+in that order.) The R, G, B, and A values are not clamped to [0,1] at
+any time during this process.
Each pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
@code{GL_POST_CONVOLUTION_c_SCALE} parameters and biased by their
corresponding @code{GL_POST_CONVOLUTION_c_BIAS} parameters (where
@var{c} takes on the values @strong{RED}, @strong{GREEN}, @strong{BLUE},
-and @strong{ALPHA}). These parameters are set by @code{glPixelTransfer}.
+and @strong{ALPHA}). These parameters are set by
+@code{glPixelTransfer}.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_CONVOLUTION_1D}.
of the allowable values.
@code{GL_INVALID_VALUE} is generated if @var{width} is less than zero or
-greater than the maximum supported value. This value may be queried with
-@code{glGetConvolutionParameter} using target @code{GL_CONVOLUTION_1D}
-and name @code{GL_MAX_CONVOLUTION_WIDTH}.
+greater than the maximum supported value. This value may be queried
+with @code{glGetConvolutionParameter} using target
+@code{GL_CONVOLUTION_1D} and name @code{GL_MAX_CONVOLUTION_WIDTH}.
@code{GL_INVALID_OPERATION} is generated if
@code{glCopyConvolutionFilter1D} is executed between the execution of
Must be @code{GL_CONVOLUTION_2D}.
@item @var{internalformat}
-The internal format of the convolution filter kernel. The allowable
+The internal format of the convolution filter kernel. The allowable
values are @code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8},
@code{GL_ALPHA12}, @code{GL_ALPHA16}, @code{GL_LUMINANCE},
@code{GL_LUMINANCE4}, @code{GL_LUMINANCE8}, @code{GL_LUMINANCE12},
The screen-aligned pixel rectangle with lower-left corner at (@var{x},\
@var{y}), width @var{width} and height @var{height} is used to define
-the convolution filter. If any pixels within this region are outside the
-window that is associated with the GL context, the values obtained for
-those pixels are undefined.
+the convolution filter. If any pixels within this region are outside
+the window that is associated with the GL context, the values obtained
+for those pixels are undefined.
The pixels in the rectangle are processed exactly as if
@code{glReadPixels} had been called with @var{format} set to RGBA, but
-the process stops just before final conversion. The R, G, B, and A
+the process stops just before final conversion. The R, G, B, and A
components of each pixel are next scaled by the four 2D
@code{GL_CONVOLUTION_FILTER_SCALE} parameters and biased by the four 2D
-@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
+@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
parameters are set by @code{glConvolutionParameter} using the
@code{GL_CONVOLUTION_2D} target and the names
@code{GL_CONVOLUTION_FILTER_SCALE} and
-@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are vectors
-of four values that are applied to red, green, blue, and alpha, in that
-order.) The R, G, B, and A values are not clamped to [0,1] at any time
-during this process.
+@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are
+vectors of four values that are applied to red, green, blue, and alpha,
+in that order.) The R, G, B, and A values are not clamped to [0,1] at
+any time during this process.
Each pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
@code{GL_POST_CONVOLUTION_c_SCALE} parameters and biased by their
corresponding @code{GL_POST_CONVOLUTION_c_BIAS} parameters (where
@var{c} takes on the values @strong{RED}, @strong{GREEN}, @strong{BLUE},
-and @strong{ALPHA}). These parameters are set by @code{glPixelTransfer}.
+and @strong{ALPHA}). These parameters are set by
+@code{glPixelTransfer}.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_CONVOLUTION_2D}.
of the allowable values.
@code{GL_INVALID_VALUE} is generated if @var{width} is less than zero or
-greater than the maximum supported value. This value may be queried with
-@code{glGetConvolutionParameter} using target @code{GL_CONVOLUTION_2D}
-and name @code{GL_MAX_CONVOLUTION_WIDTH}.
+greater than the maximum supported value. This value may be queried
+with @code{glGetConvolutionParameter} using target
+@code{GL_CONVOLUTION_2D} and name @code{GL_MAX_CONVOLUTION_WIDTH}.
@code{GL_INVALID_VALUE} is generated if @var{height} is less than zero
-or greater than the maximum supported value. This value may be queried
+or greater than the maximum supported value. This value may be queried
with @code{glGetConvolutionParameter} using target
@code{GL_CONVOLUTION_2D} and name @code{GL_MAX_CONVOLUTION_HEIGHT}.
@item @var{type}
Specifies whether color values, depth values, or stencil values are to
-be copied. Symbolic constants @code{GL_COLOR}, @code{GL_DEPTH}, and
+be copied. Symbolic constants @code{GL_COLOR}, @code{GL_DEPTH}, and
@code{GL_STENCIL} are accepted.
@end table
@code{glCopyPixels} copies a screen-aligned rectangle of pixels from the
specified frame buffer location to a region relative to the current
-raster position. Its operation is well defined only if the entire pixel
-source region is within the exposed portion of the window. Results of
+raster position. Its operation is well defined only if the entire pixel
+source region is within the exposed portion of the window. Results of
copies from outside the window, or from regions of the window that are
not exposed, are hardware dependent and undefined.
@var{x} and @var{y} specify the window coordinates of the lower left
-corner of the rectangular region to be copied. @var{width} and
+corner of the rectangular region to be copied. @var{width} and
@var{height} specify the dimensions of the rectangular region to be
-copied. Both @var{width} and @var{height} must not be negative.
+copied. Both @var{width} and @var{height} must not be negative.
Several parameters control the processing of the pixel data while it is
-being copied. These parameters are set with three commands:
-@code{glPixelTransfer}, @code{glPixelMap}, and @code{glPixelZoom}. This
+being copied. These parameters are set with three commands:
+@code{glPixelTransfer}, @code{glPixelMap}, and @code{glPixelZoom}. This
reference page describes the effects on @code{glCopyPixels} of most, but
not all, of the parameters specified by these three commands.
@code{glCopyPixels} copies values from each pixel with the lower
left-hand corner at @r{(@var{x}+@var{i},@var{y}+@var{j})} for
-@r{0<=@var{i}<@var{width}} and @r{0<=@var{j}<@var{height}}. This pixel
-is said to be the @r{@var{i}}th pixel in the @r{@var{j}}th row. Pixels
+@r{0<=@var{i}<@var{width}} and @r{0<=@var{j}<@var{height}}. This pixel
+is said to be the @r{@var{i}}th pixel in the @r{@var{j}}th row. Pixels
are copied in row order from the lowest to the highest row, left to
right in each row.
@var{type} specifies whether color, depth, or stencil data is to be
-copied. The details of the transfer for each data type are as follows:
+copied. The details of the transfer for each data type are as follows:
@table @asis
@item @code{GL_COLOR}
Indices or RGBA colors are read from the buffer currently specified as
-the read source buffer (see @code{glReadBuffer}). If the GL is in color
+the read source buffer (see @code{glReadBuffer}). If the GL is in color
index mode, each index that is read from this buffer is converted to a
fixed-point format with an unspecified number of bits to the right of
-the binary point. Each index is then shifted left by
-@code{GL_INDEX_SHIFT} bits, and added to @code{GL_INDEX_OFFSET}. If
-@code{GL_INDEX_SHIFT} is negative, the shift is to the right. In either
+the binary point. Each index is then shifted left by
+@code{GL_INDEX_SHIFT} bits, and added to @code{GL_INDEX_OFFSET}. If
+@code{GL_INDEX_SHIFT} is negative, the shift is to the right. In either
case, zero bits fill otherwise unspecified bit locations in the result.
If @code{GL_MAP_COLOR} is true, the index is replaced with the value
-that it references in lookup table @code{GL_PIXEL_MAP_I_TO_I}. Whether
+that it references in lookup table @code{GL_PIXEL_MAP_I_TO_I}. Whether
the lookup replacement of the index is done or not, the integer part of
the index is then ANDed with @r{2^@var{b}-1}, where @r{@var{b}} is the
number of bits in a color index buffer.
If the GL is in RGBA mode, the red, green, blue, and alpha components of
each pixel that is read are converted to an internal floating-point
-format with unspecified precision. The conversion maps the largest
-representable component value to 1.0, and component value 0 to 0.0. The
+format with unspecified precision. The conversion maps the largest
+representable component value to 1.0, and component value 0 to 0.0. The
resulting floating-point color values are then multiplied by
@code{GL_c_SCALE} and added to @code{GL_c_BIAS}, where @var{c} is RED,
-GREEN, BLUE, and ALPHA for the respective color components. The results
-are clamped to the range [0,1]. If @code{GL_MAP_COLOR} is true, each
+GREEN, BLUE, and ALPHA for the respective color components. The results
+are clamped to the range [0,1]. If @code{GL_MAP_COLOR} is true, each
color component is scaled by the size of lookup table
@code{GL_PIXEL_MAP_c_TO_c}, then replaced by the value that it
-references in that table. @var{c} is R, G, B, or A.
+references in that table. @var{c} is R, G, B, or A.
If the @code{ARB_imaging} extension is supported, the color values may
be additionally processed by color-table lookups, color-matrix
@r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster position,
and the pixel was the @r{@var{i}}th pixel in the @r{@var{j}}th row.
These pixel fragments are then treated just like the fragments generated
-by rasterizing points, lines, or polygons. Texture mapping, fog, and all
-the fragment operations are applied before the fragments are written to
-the frame buffer.
+by rasterizing points, lines, or polygons. Texture mapping, fog, and
+all the fragment operations are applied before the fragments are written
+to the frame buffer.
@item @code{GL_DEPTH}
Depth values are read from the depth buffer and converted directly to an
-internal floating-point format with unspecified precision. The resulting
-floating-point depth value is then multiplied by @code{GL_DEPTH_SCALE}
-and added to @code{GL_DEPTH_BIAS}. The result is clamped to the range
-[0,1].
+internal floating-point format with unspecified precision. The
+resulting floating-point depth value is then multiplied by
+@code{GL_DEPTH_SCALE} and added to @code{GL_DEPTH_BIAS}. The result is
+clamped to the range [0,1].
The GL then converts the resulting depth components to fragments by
attaching the current raster position color or color index and texture
@r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster position,
and the pixel was the @r{@var{i}}th pixel in the @r{@var{j}}th row.
These pixel fragments are then treated just like the fragments generated
-by rasterizing points, lines, or polygons. Texture mapping, fog, and all
-the fragment operations are applied before the fragments are written to
-the frame buffer.
+by rasterizing points, lines, or polygons. Texture mapping, fog, and
+all the fragment operations are applied before the fragments are written
+to the frame buffer.
@item @code{GL_STENCIL}
Stencil indices are read from the stencil buffer and converted to an
internal fixed-point format with an unspecified number of bits to the
-right of the binary point. Each fixed-point index is then shifted left
-by @code{GL_INDEX_SHIFT} bits, and added to @code{GL_INDEX_OFFSET}. If
-@code{GL_INDEX_SHIFT} is negative, the shift is to the right. In either
+right of the binary point. Each fixed-point index is then shifted left
+by @code{GL_INDEX_SHIFT} bits, and added to @code{GL_INDEX_OFFSET}. If
+@code{GL_INDEX_SHIFT} is negative, the shift is to the right. In either
case, zero bits fill otherwise unspecified bit locations in the result.
If @code{GL_MAP_STENCIL} is true, the index is replaced with the value
-that it references in lookup table @code{GL_PIXEL_MAP_S_TO_S}. Whether
+that it references in lookup table @code{GL_PIXEL_MAP_S_TO_S}. Whether
the lookup replacement of the index is done or not, the integer part of
the index is then ANDed with @r{2^@var{b}-1}, where @r{@var{b}} is the
-number of bits in the stencil buffer. The resulting stencil indices are
+number of bits in the stencil buffer. The resulting stencil indices are
then written to the stencil buffer such that the index read from the
@r{@var{i}}th location of the @r{@var{j}}th row is written to location
@r{(@var{x}_@var{r}+@var{i},@var{y}_@var{r}+@var{j})}, where
The rasterization described thus far assumes pixel zoom factors of 1.0.
If @code{glPixelZoom} is used to change the @r{@var{x}} and @r{@var{y}}
-pixel zoom factors, pixels are converted to fragments as follows. If
+pixel zoom factors, pixels are converted to fragments as follows. If
@r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster position,
and a given pixel is in the @r{@var{i}}th location in the @r{@var{j}}th
row of the source pixel rectangle, then fragments are generated for
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalformat}
-Specifies the internal format of the texture. Must be one of the
+Specifies the internal format of the texture. Must be one of the
following symbolic constants: @code{GL_ALPHA}, @code{GL_ALPHA4},
@code{GL_ALPHA8}, @code{GL_ALPHA12}, @code{GL_ALPHA16},
@code{GL_COMPRESSED_ALPHA}, @code{GL_COMPRESSED_LUMINANCE},
to be copied.
@item @var{width}
-Specifies the width of the texture image. Must be 0 or
-@r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. The height
-of the texture image is 1.
+Specifies the width of the texture image. Must be 0 or
+@r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. The
+height of the texture image is 1.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@end table
@var{internalformat} specifies the internal format of the texture array.
The pixels in the row are processed exactly as if @code{glCopyPixels}
-had been called, but the process stops just before final conversion. At
+had been called, but the process stops just before final conversion. At
this point all pixel component values are clamped to the range @r{[0,1]}
and then converted to the texture's internal format for storage in the
texel array.
pixels from the current @code{GL_READ_BUFFER}.
When @var{internalformat} is one of the sRGB types, the GL does not
-automatically convert the source pixels to the sRGB color space. In this
-case, the @code{glPixelMap} function can be used to accomplish the
+automatically convert the source pixels to the sRGB color space. In
+this case, the @code{glPixelMap} function can be used to accomplish the
conversion.
@code{GL_INVALID_ENUM} is generated if @var{target} is not one of the
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalformat}
-Specifies the internal format of the texture. Must be one of the
+Specifies the internal format of the texture. Must be one of the
following symbolic constants: @code{GL_ALPHA}, @code{GL_ALPHA4},
@code{GL_ALPHA8}, @code{GL_ALPHA12}, @code{GL_ALPHA16},
@code{GL_COMPRESSED_ALPHA}, @code{GL_COMPRESSED_LUMINANCE},
rectangular region of pixels to be copied.
@item @var{width}
-Specifies the width of the texture image. Must be 0 or
+Specifies the width of the texture image. Must be 0 or
@r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}.
@item @var{height}
-Specifies the height of the texture image. Must be 0 or
+Specifies the height of the texture image. Must be 0 or
@r{2^@var{m}+2(@var{border},)} for some integer @r{@var{m}}.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@end table
The screen-aligned pixel rectangle with lower left corner at (@var{x},
@var{y}) and with a width of @r{@var{width}+2(@var{border},)} and a
height of @r{@var{height}+2(@var{border},)} defines the texture array
-at the mipmap level specified by @var{level}. @var{internalformat}
+at the mipmap level specified by @var{level}. @var{internalformat}
specifies the internal format of the texture array.
The pixels in the rectangle are processed exactly as if
@code{glCopyPixels} had been called, but the process stops just before
-final conversion. At this point all pixel component values are clamped
+final conversion. At this point all pixel component values are clamped
to the range @r{[0,1]} and then converted to the texture's internal
format for storage in the texel array.
undefined.
When @var{internalformat} is one of the sRGB types, the GL does not
-automatically convert the source pixels to the sRGB color space. In this
-case, the @code{glPixelMap} function can be used to accomplish the
+automatically convert the source pixels to the sRGB color space. In
+this case, the @code{glPixelMap} function can be used to accomplish the
conversion.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
The screen-aligned pixel row with left corner at (@var{x},\ @var{y}),
and with length @var{width} replaces the portion of the texture array
with x indices @var{xoffset} through @r{@var{xoffset}+@var{width}-1},
-inclusive. The destination in the texture array may not include any
+inclusive. The destination in the texture array may not include any
texels outside the texture array as it was originally specified.
The pixels in the row are processed exactly as if @code{glCopyPixels}
-had been called, but the process stops just before final conversion. At
+had been called, but the process stops just before final conversion. At
this point, all pixel component values are clamped to the range
@r{[0,1]} and then converted to the texture's internal format for
storage in the texel array.
It is not an error to specify a subtexture with zero width, but such a
-specification has no effect. If any of the pixels within the specified
+specification has no effect. If any of the pixels within the specified
row of the current @code{GL_READ_BUFFER} are outside the read window
associated with the current rendering context, then the values obtained
for those pixels are undefined.
@code{GL_INVALID_VALUE} is generated if @r{@var{xoffset}<-@var{b}}, or
@r{(@var{xoffset}+@var{width},)>(@var{w}-@var{b},)}, where @r{@var{w}}
is the @code{GL_TEXTURE_WIDTH} and @r{@var{b}} is the
-@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
+@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
@r{@var{w}} includes twice the border width.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
The pixels in the rectangle are processed exactly as if
@code{glCopyPixels} had been called, but the process stops just before
-final conversion. At this point, all pixel component values are clamped
+final conversion. At this point, all pixel component values are clamped
to the range @r{[0,1]} and then converted to the texture's internal
format for storage in the texel array.
The destination rectangle in the texture array may not include any
-texels outside the texture array as it was originally specified. It is
+texels outside the texture array as it was originally specified. It is
not an error to specify a subtexture with zero width or height, but such
a specification has no effect.
@r{(@var{yoffset}+@var{height},)>(@var{h}-@var{b},)}, where @r{@var{w}}
is the @code{GL_TEXTURE_WIDTH}, @r{@var{h}} is the
@code{GL_TEXTURE_HEIGHT}, and @r{@var{b}} is the
-@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
+@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
@r{@var{w}} and @r{@var{h}} include twice the border width.
@code{GL_INVALID_OPERATION} is generated if @code{glCopyTexSubImage2D}
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_3D}
+Specifies the target texture. Must be @code{GL_TEXTURE_3D}
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
The pixels in the rectangle are processed exactly as if
@code{glCopyPixels} had been called, but the process stops just before
-final conversion. At this point, all pixel component values are clamped
+final conversion. At this point, all pixel component values are clamped
to the range @r{[0,1]} and then converted to the texture's internal
format for storage in the texel array.
The destination rectangle in the texture array may not include any
-texels outside the texture array as it was originally specified. It is
+texels outside the texture array as it was originally specified. It is
not an error to specify a subtexture with zero width or height, but such
a specification has no effect.
@r{(@var{zoffset}+1,)>(@var{d}-@var{b},)}, where @r{@var{w}} is the
@code{GL_TEXTURE_WIDTH}, @r{@var{h}} is the @code{GL_TEXTURE_HEIGHT},
@r{@var{d}} is the @code{GL_TEXTURE_DEPTH}, and @r{@var{b}} is the
-@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
+@code{GL_TEXTURE_BORDER} of the texture image being modified. Note that
@r{@var{w}}, @r{@var{h}}, and @r{@var{d}} include twice the border
width.
Creates a program object.
@code{glCreateProgram} creates an empty program object and returns a
-non-zero value by which it can be referenced. A program object is an
-object to which shader objects can be attached. This provides a
+non-zero value by which it can be referenced. A program object is an
+object to which shader objects can be attached. This provides a
mechanism to specify the shader objects that will be linked to create a
-program. It also provides a means for checking the compatibility of the
+program. It also provides a means for checking the compatibility of the
shaders that will be used to create a program (for instance, checking
-the compatibility between a vertex shader and a fragment shader). When
+the compatibility between a vertex shader and a fragment shader). When
no longer needed as part of a program object, shader objects can be
detached.
One or more executables are created in a program object by successfully
attaching shader objects to it with @code{glAttachShader}, successfully
compiling the shader objects with @code{glCompileShader}, and
-successfully linking the program object with @code{glLinkProgram}. These
+successfully linking the program object with @code{glLinkProgram}. These
executables are made part of current state when @code{glUseProgram} is
-called. Program objects can be deleted by calling
-@code{glDeleteProgram}. The memory associated with the program object
+called. Program objects can be deleted by calling
+@code{glDeleteProgram}. The memory associated with the program object
will be deleted when it is no longer part of current rendering state for
any context.
@table @asis
@item @var{shaderType}
-Specifies the type of shader to be created. Must be either
+Specifies the type of shader to be created. Must be either
@code{GL_VERTEX_SHADER} or @code{GL_FRAGMENT_SHADER}.
@end table
@code{glCreateShader} creates an empty shader object and returns a
-non-zero value by which it can be referenced. A shader object is used to
-maintain the source code strings that define a shader. @var{shaderType}
-indicates the type of shader to be created. Two types of shaders are
-supported. A shader of type @code{GL_VERTEX_SHADER} is a shader that is
-intended to run on the programmable vertex processor and replace the
-fixed functionality vertex processing in OpenGL. A shader of type
-@code{GL_FRAGMENT_SHADER} is a shader that is intended to run on the
-programmable fragment processor and replace the fixed functionality
+non-zero value by which it can be referenced. A shader object is used
+to maintain the source code strings that define a shader.
+@var{shaderType} indicates the type of shader to be created. Two types
+of shaders are supported. A shader of type @code{GL_VERTEX_SHADER} is a
+shader that is intended to run on the programmable vertex processor and
+replace the fixed functionality vertex processing in OpenGL. A shader
+of type @code{GL_FRAGMENT_SHADER} is a shader that is intended to run on
+the programmable fragment processor and replace the fixed functionality
fragment processing in OpenGL.
When created, a shader object's @code{GL_SHADER_TYPE} parameter is set
@table @asis
@item @var{mode}
Specifies whether front- or back-facing facets are candidates for
-culling. Symbolic constants @code{GL_FRONT}, @code{GL_BACK}, and
-@code{GL_FRONT_AND_BACK} are accepted. The initial value is
+culling. Symbolic constants @code{GL_FRONT}, @code{GL_BACK}, and
+@code{GL_FRONT_AND_BACK} are accepted. The initial value is
@code{GL_BACK}.
@end table
@code{glCullFace} specifies whether front- or back-facing facets are
-culled (as specified by @var{mode}) when facet culling is enabled. Facet
-culling is initially disabled. To enable and disable facet culling, call
-the @code{glEnable} and @code{glDisable} commands with the argument
-@code{GL_CULL_FACE}. Facets include triangles, quadrilaterals, polygons,
-and rectangles.
+culled (as specified by @var{mode}) when facet culling is enabled. Facet
+culling is initially disabled. To enable and disable facet culling,
+call the @code{glEnable} and @code{glDisable} commands with the argument
+@code{GL_CULL_FACE}. Facets include triangles, quadrilaterals,
+polygons, and rectangles.
@code{glFrontFace} specifies which of the clockwise and counterclockwise
-facets are front-facing and back-facing. See @code{glFrontFace}.
+facets are front-facing and back-facing. See @code{glFrontFace}.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
value.
@end table
@code{glDeleteBuffers} deletes @var{n} buffer objects named by the
-elements of the array @var{buffers}. After a buffer object is deleted,
+elements of the array @var{buffers}. After a buffer object is deleted,
it has no contents, and its name is free for reuse (for example by
-@code{glGenBuffers}). If a buffer object that is currently bound is
+@code{glGenBuffers}). If a buffer object that is currently bound is
deleted, the binding reverts to 0 (the absence of any buffer object,
which reverts to client memory usage).
@end table
@code{glDeleteLists} causes a contiguous group of display lists to be
-deleted. @var{list} is the name of the first display list to be deleted,
-and @var{range} is the number of display lists to delete. All display
-lists @r{@var{d}} with @r{@var{list}<=@var{d}<=@var{list}+@var{range}-1}
-are deleted.
+deleted. @var{list} is the name of the first display list to be
+deleted, and @var{range} is the number of display lists to delete. All
+display lists @r{@var{d}} with
+@r{@var{list}<=@var{d}<=@var{list}+@var{range}-1} are deleted.
All storage locations allocated to the specified display lists are
-freed, and the names are available for reuse at a later time. Names
+freed, and the names are available for reuse at a later time. Names
within the range that do not have an associated display list are
-ignored. If @var{range} is 0, nothing happens.
+ignored. If @var{range} is 0, nothing happens.
@code{GL_INVALID_VALUE} is generated if @var{range} is negative.
If a program object is in use as part of current rendering state, it
will be flagged for deletion, but it will not be deleted until it is no
-longer part of current state for any rendering context. If a program
+longer part of current state for any rendering context. If a program
object to be deleted has shader objects attached to it, those shader
objects will be automatically detached but not deleted unless they have
already been flagged for deletion by a previous call to
-@code{glDeleteShader}. A value of 0 for @var{program} will be silently
+@code{glDeleteShader}. A value of 0 for @var{program} will be silently
ignored.
To determine whether a program object has been flagged for deletion,
@end table
@code{glDeleteQueries} deletes @var{n} query objects named by the
-elements of the array @var{ids}. After a query object is deleted, it has
-no contents, and its name is free for reuse (for example by
+elements of the array @var{ids}. After a query object is deleted, it
+has no contents, and its name is free for reuse (for example by
@code{glGenQueries}).
@code{glDeleteQueries} silently ignores 0's and names that do not
@end table
@code{glDeleteShader} frees the memory and invalidates the name
-associated with the shader object specified by @var{shader}. This
+associated with the shader object specified by @var{shader}. This
command effectively undoes the effects of a call to
@code{glCreateShader}.
will be flagged for deletion, but it will not be deleted until it is no
longer attached to any program object, for any rendering context (i.e.,
it must be detached from wherever it was attached before it will be
-deleted). A value of 0 for @var{shader} will be silently ignored.
+deleted). A value of 0 for @var{shader} will be silently ignored.
To determine whether an object has been flagged for deletion, call
@code{glGetShader} with arguments @var{shader} and
@end table
@code{glDeleteTextures} deletes @var{n} textures named by the elements
-of the array @var{textures}. After a texture is deleted, it has no
+of the array @var{textures}. After a texture is deleted, it has no
contents or dimensionality, and its name is free for reuse (for example
-by @code{glGenTextures}). If a texture that is currently bound is
+by @code{glGenTextures}). If a texture that is currently bound is
deleted, the binding reverts to 0 (the default texture).
@code{glDeleteTextures} silently ignores 0's and names that do not
@table @asis
@item @var{func}
-Specifies the depth comparison function. Symbolic constants
+Specifies the depth comparison function. Symbolic constants
@code{GL_NEVER}, @code{GL_LESS}, @code{GL_EQUAL}, @code{GL_LEQUAL},
@code{GL_GREATER}, @code{GL_NOTEQUAL}, @code{GL_GEQUAL}, and
-@code{GL_ALWAYS} are accepted. The initial value is @code{GL_LESS}.
+@code{GL_ALWAYS} are accepted. The initial value is @code{GL_LESS}.
@end table
@code{glDepthFunc} specifies the function used to compare each incoming
-pixel depth value with the depth value present in the depth buffer. The
-comparison is performed only if depth testing is enabled. (See
+pixel depth value with the depth value present in the depth buffer. The
+comparison is performed only if depth testing is enabled. (See
@code{glEnable} and @code{glDisable} of @code{GL_DEPTH_TEST}.)
@var{func} specifies the conditions under which the pixel will be drawn.
@end table
-The initial value of @var{func} is @code{GL_LESS}. Initially, depth
-testing is disabled. If depth testing is disabled or if no depth buffer
+The initial value of @var{func} is @code{GL_LESS}. Initially, depth
+testing is disabled. If depth testing is disabled or if no depth buffer
exists, it is as if the depth test always passes.
@code{GL_INVALID_ENUM} is generated if @var{func} is not an accepted
@table @asis
@item @var{flag}
-Specifies whether the depth buffer is enabled for writing. If @var{flag}
-is @code{GL_FALSE}, depth buffer writing is disabled. Otherwise, it is
-enabled. Initially, depth buffer writing is enabled.
+Specifies whether the depth buffer is enabled for writing. If
+@var{flag} is @code{GL_FALSE}, depth buffer writing is disabled.
+Otherwise, it is enabled. Initially, depth buffer writing is enabled.
@end table
@code{glDepthMask} specifies whether the depth buffer is enabled for
-writing. If @var{flag} is @code{GL_FALSE}, depth buffer writing is
-disabled. Otherwise, it is enabled. Initially, depth buffer writing is
+writing. If @var{flag} is @code{GL_FALSE}, depth buffer writing is
+disabled. Otherwise, it is enabled. Initially, depth buffer writing is
enabled.
@code{GL_INVALID_OPERATION} is generated if @code{glDepthMask} is
After clipping and division by @var{w}, depth coordinates range from
@r{-1} to 1, corresponding to the near and far clipping planes.
@code{glDepthRange} specifies a linear mapping of the normalized depth
-coordinates in this range to window depth coordinates. Regardless of the
-actual depth buffer implementation, window coordinate depth values are
-treated as though they range from 0 through 1 (like color components).
-Thus, the values accepted by @code{glDepthRange} are both clamped to
-this range before they are accepted.
+coordinates in this range to window depth coordinates. Regardless of
+the actual depth buffer implementation, window coordinate depth values
+are treated as though they range from 0 through 1 (like color
+components). Thus, the values accepted by @code{glDepthRange} are both
+clamped to this range before they are accepted.
The setting of (0,1) maps the near plane to 0 and the far plane to 1.
With this mapping, the depth buffer range is fully utilized.
@end table
@code{glDetachShader} detaches the shader object specified by
-@var{shader} from the program object specified by @var{program}. This
+@var{shader} from the program object specified by @var{program}. This
command can be used to undo the effect of the command
@code{glAttachShader}.
@table @asis
@item @var{mode}
-Specifies what kind of primitives to render. Symbolic constants
+Specifies what kind of primitives to render. Symbolic constants
@code{GL_POINTS}, @code{GL_LINE_STRIP}, @code{GL_LINE_LOOP},
@code{GL_LINES}, @code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN},
@code{GL_TRIANGLES}, @code{GL_QUAD_STRIP}, @code{GL_QUADS}, and
@end table
@code{glDrawArrays} specifies multiple geometric primitives with very
-few subroutine calls. Instead of calling a GL procedure to pass each
+few subroutine calls. Instead of calling a GL procedure to pass each
individual vertex, normal, texture coordinate, edge flag, or color, you
can prespecify separate arrays of vertices, normals, and colors and use
them to construct a sequence of primitives with a single call to
When @code{glDrawArrays} is called, it uses @var{count} sequential
elements from each enabled array to construct a sequence of geometric
-primitives, beginning with element @var{first}. @var{mode} specifies
+primitives, beginning with element @var{first}. @var{mode} specifies
what kind of primitives are constructed and how the array elements
-construct those primitives. If @code{GL_VERTEX_ARRAY} is not enabled, no
-geometric primitives are generated.
+construct those primitives. If @code{GL_VERTEX_ARRAY} is not enabled,
+no geometric primitives are generated.
Vertex attributes that are modified by @code{glDrawArrays} have an
-unspecified value after @code{glDrawArrays} returns. For example, if
+unspecified value after @code{glDrawArrays} returns. For example, if
@code{GL_COLOR_ARRAY} is enabled, the value of the current color is
-undefined after @code{glDrawArrays} executes. Attributes that aren't
+undefined after @code{glDrawArrays} executes. Attributes that aren't
modified remain well defined.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
@end table
@code{glDrawBuffers} defines an array of buffers into which fragment
-color values or fragment data will be written. If no fragment shader is
+color values or fragment data will be written. If no fragment shader is
active, rendering operations will generate only one fragment color per
fragment and it will be written into each of the buffers specified by
-@var{bufs}. If a fragment shader is active and it writes a value to the
+@var{bufs}. If a fragment shader is active and it writes a value to the
output variable @code{gl_FragColor}, then that value will be written
-into each of the buffers specified by @var{bufs}. If a fragment shader
+into each of the buffers specified by @var{bufs}. If a fragment shader
is active and it writes a value to one or more elements of the output
array variable @code{gl_FragData[]}, then the value of
@code{gl_FragData[0] } will be written into the first buffer specified
by @var{bufs}, the value of @code{gl_FragData[1] } will be written into
the second buffer specified by @var{bufs}, and so on up to
-@code{gl_FragData[n-1]}. The draw buffer used for @code{gl_FragData[n]}
+@code{gl_FragData[n-1]}. The draw buffer used for @code{gl_FragData[n]}
and beyond is implicitly set to be @code{GL_NONE}.
The symbolic constants contained in @var{bufs} may be any of the
@end table
Except for @code{GL_NONE}, the preceding symbolic constants may not
-appear more than once in @var{bufs}. The maximum number of draw buffers
+appear more than once in @var{bufs}. The maximum number of draw buffers
supported is implementation dependent and can be queried by calling
-@code{glGet} with the argument @code{GL_MAX_DRAW_BUFFERS}. The number of
-auxiliary buffers can be queried by calling @code{glGet} with the
+@code{glGet} with the argument @code{GL_MAX_DRAW_BUFFERS}. The number
+of auxiliary buffers can be queried by calling @code{glGet} with the
argument @code{GL_AUX_BUFFERS}.
@code{GL_INVALID_ENUM} is generated if one of the values in @var{bufs}
@table @asis
@item @var{mode}
-Specifies up to four color buffers to be drawn into. Symbolic constants
+Specifies up to four color buffers to be drawn into. Symbolic constants
@code{GL_NONE}, @code{GL_FRONT_LEFT}, @code{GL_FRONT_RIGHT},
@code{GL_BACK_LEFT}, @code{GL_BACK_RIGHT}, @code{GL_FRONT},
@code{GL_BACK}, @code{GL_LEFT}, @code{GL_RIGHT},
@end table
When colors are written to the frame buffer, they are written into the
-color buffers specified by @code{glDrawBuffer}. The specifications are
+color buffers specified by @code{glDrawBuffer}. The specifications are
as follows:
@table @asis
Only the back right color buffer is written.
@item @code{GL_FRONT}
-Only the front left and front right color buffers are written. If there
+Only the front left and front right color buffers are written. If there
is no front right color buffer, only the front left color buffer is
written.
@item @code{GL_BACK}
-Only the back left and back right color buffers are written. If there is
-no back right color buffer, only the back left color buffer is written.
+Only the back left and back right color buffers are written. If there
+is no back right color buffer, only the back left color buffer is
+written.
@item @code{GL_LEFT}
-Only the front left and back left color buffers are written. If there is
-no back left color buffer, only the front left color buffer is written.
+Only the front left and back left color buffers are written. If there
+is no back left color buffer, only the front left color buffer is
+written.
@item @code{GL_RIGHT}
-Only the front right and back right color buffers are written. If there
+Only the front right and back right color buffers are written. If there
is no back right color buffer, only the front right color buffer is
written.
@item @code{GL_FRONT_AND_BACK}
All the front and back color buffers (front left, front right, back
-left, back right) are written. If there are no back color buffers, only
-the front left and front right color buffers are written. If there are
+left, back right) are written. If there are no back color buffers, only
+the front left and front right color buffers are written. If there are
no right color buffers, only the front left and back left color buffers
-are written. If there are no right or back color buffers, only the front
-left color buffer is written.
+are written. If there are no right or back color buffers, only the
+front left color buffer is written.
@item @code{GL_AUX}@var{i}
Only auxiliary color buffer @var{i} is written.
buffer and can produce different results in each buffer.
Monoscopic contexts include only @var{left} buffers, and stereoscopic
-contexts include both @var{left} and @var{right} buffers. Likewise,
+contexts include both @var{left} and @var{right} buffers. Likewise,
single-buffered contexts include only @var{front} buffers, and
double-buffered contexts include both @var{front} and @var{back}
-buffers. The context is selected at GL initialization.
+buffers. The context is selected at GL initialization.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
value.
@table @asis
@item @var{mode}
-Specifies what kind of primitives to render. Symbolic constants
+Specifies what kind of primitives to render. Symbolic constants
@code{GL_POINTS}, @code{GL_LINE_STRIP}, @code{GL_LINE_LOOP},
@code{GL_LINES}, @code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN},
@code{GL_TRIANGLES}, @code{GL_QUAD_STRIP}, @code{GL_QUADS}, and
Specifies the number of elements to be rendered.
@item @var{type}
-Specifies the type of the values in @var{indices}. Must be one of
+Specifies the type of the values in @var{indices}. Must be one of
@code{GL_UNSIGNED_BYTE}, @code{GL_UNSIGNED_SHORT}, or
@code{GL_UNSIGNED_INT}.
@end table
@code{glDrawElements} specifies multiple geometric primitives with very
-few subroutine calls. Instead of calling a GL function to pass each
+few subroutine calls. Instead of calling a GL function to pass each
individual vertex, normal, texture coordinate, edge flag, or color, you
can prespecify separate arrays of vertices, normals, and so on, and use
them to construct a sequence of primitives with a single call to
When @code{glDrawElements} is called, it uses @var{count} sequential
elements from an enabled array, starting at @var{indices} to construct a
-sequence of geometric primitives. @var{mode} specifies what kind of
+sequence of geometric primitives. @var{mode} specifies what kind of
primitives are constructed and how the array elements construct these
-primitives. If more than one array is enabled, each is used. If
+primitives. If more than one array is enabled, each is used. If
@code{GL_VERTEX_ARRAY} is not enabled, no geometric primitives are
constructed.
Vertex attributes that are modified by @code{glDrawElements} have an
-unspecified value after @code{glDrawElements} returns. For example, if
+unspecified value after @code{glDrawElements} returns. For example, if
@code{GL_COLOR_ARRAY} is enabled, the value of the current color is
-undefined after @code{glDrawElements} executes. Attributes that aren't
+undefined after @code{glDrawElements} executes. Attributes that aren't
modified maintain their previous values.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
frame buffer.
@item @var{format}
-Specifies the format of the pixel data. Symbolic constants
+Specifies the format of the pixel data. Symbolic constants
@code{GL_COLOR_INDEX}, @code{GL_STENCIL_INDEX},
@code{GL_DEPTH_COMPONENT}, @code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA},
@code{GL_BGRA}, @code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE},
accepted.
@item @var{type}
-Specifies the data type for @var{data}. Symbolic constants
+Specifies the data type for @var{data}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@code{glDrawPixels} reads pixel data from memory and writes it into the
frame buffer relative to the current raster position, provided that the
-raster position is valid. Use @code{glRasterPos} or @code{glWindowPos}
+raster position is valid. Use @code{glRasterPos} or @code{glWindowPos}
to set the current raster position; use @code{glGet} with argument
@code{GL_CURRENT_RASTER_POSITION_VALID} to determine if the specified
raster position is valid, and @code{glGet} with argument
Several parameters define the encoding of pixel data in memory and
control the processing of the pixel data before it is placed in the
-frame buffer. These parameters are set with four commands:
+frame buffer. These parameters are set with four commands:
@code{glPixelStore}, @code{glPixelTransfer}, @code{glPixelMap}, and
-@code{glPixelZoom}. This reference page describes the effects on
+@code{glPixelZoom}. This reference page describes the effects on
@code{glDrawPixels} of many, but not all, of the parameters specified by
these four commands.
Data is read from @var{data} as a sequence of signed or unsigned bytes,
signed or unsigned shorts, signed or unsigned integers, or
-single-precision floating-point values, depending on @var{type}. When
+single-precision floating-point values, depending on @var{type}. When
@var{type} is one of @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, or @code{GL_FLOAT} each of these bytes, shorts, integers,
or floating-point values is interpreted as one color or depth component,
-or one index, depending on @var{format}. When @var{type} is one of
+or one index, depending on @var{format}. When @var{type} is one of
@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_SHORT_5_6_5},
@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
@code{GL_UNSIGNED_INT_8_8_8_8}, or @code{GL_UNSIGNED_INT_10_10_10_2},
each unsigned value is interpreted as containing all the components for
a single pixel, with the color components arranged according to
-@var{format}. When @var{type} is one of
+@var{format}. When @var{type} is one of
@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
@code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
@code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
@code{GL_UNSIGNED_INT_8_8_8_8_REV}, or
@code{GL_UNSIGNED_INT_2_10_10_10_REV}, each unsigned value is
interpreted as containing all color components, specified by
-@var{format}, for a single pixel in a reversed order. Indices are always
-treated individually. Color components are treated as groups of one,
-two, three, or four values, again based on @var{format}. Both individual
-indices and groups of components are referred to as pixels. If
-@var{type} is @code{GL_BITMAP}, the data must be unsigned bytes, and
+@var{format}, for a single pixel in a reversed order. Indices are
+always treated individually. Color components are treated as groups of
+one, two, three, or four values, again based on @var{format}. Both
+individual indices and groups of components are referred to as pixels.
+If @var{type} is @code{GL_BITMAP}, the data must be unsigned bytes, and
@var{format} must be either @code{GL_COLOR_INDEX} or
-@code{GL_STENCIL_INDEX}. Each unsigned byte is treated as eight 1-bit
+@code{GL_STENCIL_INDEX}. Each unsigned byte is treated as eight 1-bit
pixels, with bit ordering determined by @code{GL_UNPACK_LSB_FIRST} (see
@code{glPixelStore}).
@r{@var{width}×@var{height}} pixels are read from memory, starting at
-location @var{data}. By default, these pixels are taken from adjacent
+location @var{data}. By default, these pixels are taken from adjacent
memory locations, except that after all @var{width} pixels are read, the
-read pointer is advanced to the next four-byte boundary. The four-byte
+read pointer is advanced to the next four-byte boundary. The four-byte
row alignment is specified by @code{glPixelStore} with argument
@code{GL_UNPACK_ALIGNMENT}, and it can be set to one, two, four, or
-eight bytes. Other pixel store parameters specify different read pointer
-advancements, both before the first pixel is read and after all
-@var{width} pixels are read. See the @code{glPixelStore} reference page
+eight bytes. Other pixel store parameters specify different read
+pointer advancements, both before the first pixel is read and after all
+@var{width} pixels are read. See the @code{glPixelStore} reference page
for details on these options.
If a non-zero named buffer object is bound to the
parameters specified by @code{glPixelTransfer} and @code{glPixelMap}.
The details of these operations, as well as the target buffer into which
the pixels are drawn, are specific to the format of the pixels, as
-specified by @var{format}. @var{format} can assume one of 13 symbolic
+specified by @var{format}. @var{format} can assume one of 13 symbolic
values:
@table @asis
@item @code{GL_COLOR_INDEX}
-Each pixel is a single value, a color index. It is converted to
+Each pixel is a single value, a color index. It is converted to
fixed-point format, with an unspecified number of bits to the right of
-the binary point, regardless of the memory data type. Floating-point
-values convert to true fixed-point values. Signed and unsigned integer
-data is converted with all fraction bits set to 0. Bitmap data convert
+the binary point, regardless of the memory data type. Floating-point
+values convert to true fixed-point values. Signed and unsigned integer
+data is converted with all fraction bits set to 0. Bitmap data convert
to either 0 or 1.
Each fixed-point index is then shifted left by @code{GL_INDEX_SHIFT}
-bits and added to @code{GL_INDEX_OFFSET}. If @code{GL_INDEX_SHIFT} is
-negative, the shift is to the right. In either case, zero bits fill
+bits and added to @code{GL_INDEX_OFFSET}. If @code{GL_INDEX_SHIFT} is
+negative, the shift is to the right. In either case, zero bits fill
otherwise unspecified bit locations in the result.
If the GL is in RGBA mode, the resulting index is converted to an RGBA
pixel with the help of the @code{GL_PIXEL_MAP_I_TO_R},
@code{GL_PIXEL_MAP_I_TO_G}, @code{GL_PIXEL_MAP_I_TO_B}, and
-@code{GL_PIXEL_MAP_I_TO_A} tables. If the GL is in color index mode, and
-if @code{GL_MAP_COLOR} is true, the index is replaced with the value
-that it references in lookup table @code{GL_PIXEL_MAP_I_TO_I}. Whether
+@code{GL_PIXEL_MAP_I_TO_A} tables. If the GL is in color index mode,
+and if @code{GL_MAP_COLOR} is true, the index is replaced with the value
+that it references in lookup table @code{GL_PIXEL_MAP_I_TO_I}. Whether
the lookup replacement of the index is done or not, the integer part of
the index is then ANDed with @r{2^@var{b}-1}, where @r{@var{b}} is the
number of bits in a color index buffer.
@r{@var{x}_@var{n}=@var{x}_@var{r}+@var{n}%@var{width}}@r{@var{y}_@var{n}=@var{y}_@var{r}+⌊@var{n}/@var{width},⌋}
where @r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster
-position. These pixel fragments are then treated just like the fragments
-generated by rasterizing points, lines, or polygons. Texture mapping,
-fog, and all the fragment operations are applied before the fragments
-are written to the frame buffer.
+position. These pixel fragments are then treated just like the
+fragments generated by rasterizing points, lines, or polygons. Texture
+mapping, fog, and all the fragment operations are applied before the
+fragments are written to the frame buffer.
@item @code{GL_STENCIL_INDEX}
-Each pixel is a single value, a stencil index. It is converted to
+Each pixel is a single value, a stencil index. It is converted to
fixed-point format, with an unspecified number of bits to the right of
-the binary point, regardless of the memory data type. Floating-point
-values convert to true fixed-point values. Signed and unsigned integer
-data is converted with all fraction bits set to 0. Bitmap data convert
+the binary point, regardless of the memory data type. Floating-point
+values convert to true fixed-point values. Signed and unsigned integer
+data is converted with all fraction bits set to 0. Bitmap data convert
to either 0 or 1.
Each fixed-point index is then shifted left by @code{GL_INDEX_SHIFT}
-bits, and added to @code{GL_INDEX_OFFSET}. If @code{GL_INDEX_SHIFT} is
-negative, the shift is to the right. In either case, zero bits fill
-otherwise unspecified bit locations in the result. If
+bits, and added to @code{GL_INDEX_OFFSET}. If @code{GL_INDEX_SHIFT} is
+negative, the shift is to the right. In either case, zero bits fill
+otherwise unspecified bit locations in the result. If
@code{GL_MAP_STENCIL} is true, the index is replaced with the value that
-it references in lookup table @code{GL_PIXEL_MAP_S_TO_S}. Whether the
+it references in lookup table @code{GL_PIXEL_MAP_S_TO_S}. Whether the
lookup replacement of the index is done or not, the integer part of the
index is then ANDed with @r{2^@var{b}-1}, where @r{@var{b}} is the
-number of bits in the stencil buffer. The resulting stencil indices are
+number of bits in the stencil buffer. The resulting stencil indices are
then written to the stencil buffer such that the @r{@var{n}}th index is
written to location
@r{@var{x}_@var{n}=@var{x}_@var{r}+@var{n}%@var{width}}@r{@var{y}_@var{n}=@var{y}_@var{r}+⌊@var{n}/@var{width},⌋}
where @r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster
-position. Only the pixel ownership test, the scissor test, and the
+position. Only the pixel ownership test, the scissor test, and the
stencil writemask affect these write operations.
@item @code{GL_DEPTH_COMPONENT}
-Each pixel is a single-depth component. Floating-point data is converted
-directly to an internal floating-point format with unspecified
-precision. Signed integer data is mapped linearly to the internal
+Each pixel is a single-depth component. Floating-point data is
+converted directly to an internal floating-point format with unspecified
+precision. Signed integer data is mapped linearly to the internal
floating-point format such that the most positive representable integer
value maps to 1.0, and the most negative representable value maps to
-@r{-1.0}. Unsigned integer data is mapped similarly: the largest integer
-value maps to 1.0, and 0 maps to 0.0. The resulting floating-point depth
-value is then multiplied by @code{GL_DEPTH_SCALE} and added to
-@code{GL_DEPTH_BIAS}. The result is clamped to the range @r{[0,1]}.
+@r{-1.0}. Unsigned integer data is mapped similarly: the largest
+integer value maps to 1.0, and 0 maps to 0.0. The resulting
+floating-point depth value is then multiplied by @code{GL_DEPTH_SCALE}
+and added to @code{GL_DEPTH_BIAS}. The result is clamped to the range
+@r{[0,1]}.
The GL then converts the resulting depth components to fragments by
attaching the current raster position color or color index and texture
@r{@var{x}_@var{n}=@var{x}_@var{r}+@var{n}%@var{width}}@r{@var{y}_@var{n}=@var{y}_@var{r}+⌊@var{n}/@var{width},⌋}
where @r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster
-position. These pixel fragments are then treated just like the fragments
-generated by rasterizing points, lines, or polygons. Texture mapping,
-fog, and all the fragment operations are applied before the fragments
-are written to the frame buffer.
+position. These pixel fragments are then treated just like the
+fragments generated by rasterizing points, lines, or polygons. Texture
+mapping, fog, and all the fragment operations are applied before the
+fragments are written to the frame buffer.
@item @code{GL_RGBA}
@item @code{GL_BGRA}
component is first, followed by green, followed by blue, followed by
alpha; for @code{GL_BGRA} the order is blue, green, red and then alpha.
Floating-point values are converted directly to an internal
-floating-point format with unspecified precision. Signed integer values
+floating-point format with unspecified precision. Signed integer values
are mapped linearly to the internal floating-point format such that the
most positive representable integer value maps to 1.0, and the most
-negative representable value maps to @r{-1.0}. (Note that this mapping
+negative representable value maps to @r{-1.0}. (Note that this mapping
does not convert 0 precisely to 0.0.) Unsigned integer data is mapped
-similarly: The largest integer value maps to 1.0, and 0 maps to 0.0. The
+similarly: The largest integer value maps to 1.0, and 0 maps to 0.0. The
resulting floating-point color values are then multiplied by
@code{GL_c_SCALE} and added to @code{GL_c_BIAS}, where @var{c} is RED,
-GREEN, BLUE, and ALPHA for the respective color components. The results
+GREEN, BLUE, and ALPHA for the respective color components. The results
are clamped to the range @r{[0,1]}.
If @code{GL_MAP_COLOR} is true, each color component is scaled by the
size of lookup table @code{GL_PIXEL_MAP_c_TO_c}, then replaced by the
-value that it references in that table. @var{c} is R, G, B, or A
+value that it references in that table. @var{c} is R, G, B, or A
respectively.
The GL then converts the resulting RGBA colors to fragments by attaching
@r{@var{x}_@var{n}=@var{x}_@var{r}+@var{n}%@var{width}}@r{@var{y}_@var{n}=@var{y}_@var{r}+⌊@var{n}/@var{width},⌋}
where @r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster
-position. These pixel fragments are then treated just like the fragments
-generated by rasterizing points, lines, or polygons. Texture mapping,
-fog, and all the fragment operations are applied before the fragments
-are written to the frame buffer.
+position. These pixel fragments are then treated just like the
+fragments generated by rasterizing points, lines, or polygons. Texture
+mapping, fog, and all the fragment operations are applied before the
+fragments are written to the frame buffer.
@item @code{GL_RED}
-Each pixel is a single red component. This component is converted to the
-internal floating-point format in the same way the red component of an
-RGBA pixel is. It is then converted to an RGBA pixel with green and blue
-set to 0, and alpha set to 1. After this conversion, the pixel is
+Each pixel is a single red component. This component is converted to
+the internal floating-point format in the same way the red component of
+an RGBA pixel is. It is then converted to an RGBA pixel with green and
+blue set to 0, and alpha set to 1. After this conversion, the pixel is
treated as if it had been read as an RGBA pixel.
@item @code{GL_GREEN}
-Each pixel is a single green component. This component is converted to
+Each pixel is a single green component. This component is converted to
the internal floating-point format in the same way the green component
-of an RGBA pixel is. It is then converted to an RGBA pixel with red and
-blue set to 0, and alpha set to 1. After this conversion, the pixel is
+of an RGBA pixel is. It is then converted to an RGBA pixel with red and
+blue set to 0, and alpha set to 1. After this conversion, the pixel is
treated as if it had been read as an RGBA pixel.
@item @code{GL_BLUE}
-Each pixel is a single blue component. This component is converted to
+Each pixel is a single blue component. This component is converted to
the internal floating-point format in the same way the blue component of
-an RGBA pixel is. It is then converted to an RGBA pixel with red and
-green set to 0, and alpha set to 1. After this conversion, the pixel is
+an RGBA pixel is. It is then converted to an RGBA pixel with red and
+green set to 0, and alpha set to 1. After this conversion, the pixel is
treated as if it had been read as an RGBA pixel.
@item @code{GL_ALPHA}
-Each pixel is a single alpha component. This component is converted to
+Each pixel is a single alpha component. This component is converted to
the internal floating-point format in the same way the alpha component
-of an RGBA pixel is. It is then converted to an RGBA pixel with red,
-green, and blue set to 0. After this conversion, the pixel is treated as
-if it had been read as an RGBA pixel.
+of an RGBA pixel is. It is then converted to an RGBA pixel with red,
+green, and blue set to 0. After this conversion, the pixel is treated
+as if it had been read as an RGBA pixel.
@item @code{GL_RGB}
@item @code{GL_BGR}
Each pixel is a three-component group: red first, followed by green,
followed by blue; for @code{GL_BGR}, the first component is blue,
-followed by green and then red. Each component is converted to the
+followed by green and then red. Each component is converted to the
internal floating-point format in the same way the red, green, and blue
-components of an RGBA pixel are. The color triple is converted to an
-RGBA pixel with alpha set to 1. After this conversion, the pixel is
+components of an RGBA pixel are. The color triple is converted to an
+RGBA pixel with alpha set to 1. After this conversion, the pixel is
treated as if it had been read as an RGBA pixel.
@item @code{GL_LUMINANCE}
-Each pixel is a single luminance component. This component is converted
+Each pixel is a single luminance component. This component is converted
to the internal floating-point format in the same way the red component
-of an RGBA pixel is. It is then converted to an RGBA pixel with red,
+of an RGBA pixel is. It is then converted to an RGBA pixel with red,
green, and blue set to the converted luminance value, and alpha set to
-1. After this conversion, the pixel is treated as if it had been read as
-an RGBA pixel.
+1. After this conversion, the pixel is treated as if it had been read
+as an RGBA pixel.
@item @code{GL_LUMINANCE_ALPHA}
Each pixel is a two-component group: luminance first, followed by alpha.
The two components are converted to the internal floating-point format
-in the same way the red component of an RGBA pixel is. They are then
+in the same way the red component of an RGBA pixel is. They are then
converted to an RGBA pixel with red, green, and blue set to the
converted luminance value, and alpha set to the converted alpha value.
After this conversion, the pixel is treated as if it had been read as an
-The rasterization described so far assumes pixel zoom factors of 1. If
+The rasterization described so far assumes pixel zoom factors of 1. If
@code{glPixelZoom} is used to change the @r{@var{x}} and @r{@var{y}}
-pixel zoom factors, pixels are converted to fragments as follows. If
+pixel zoom factors, pixels are converted to fragments as follows. If
@r{(@var{x}_@var{r},@var{y}_@var{r})} is the current raster position,
and a given pixel is in the @r{@var{n}}th column and @r{@var{m}}th row
of the pixel rectangle, then fragments are generated for pixels whose
@table @asis
@item @var{mode}
-Specifies what kind of primitives to render. Symbolic constants
+Specifies what kind of primitives to render. Symbolic constants
@code{GL_POINTS}, @code{GL_LINE_STRIP}, @code{GL_LINE_LOOP},
@code{GL_LINES}, @code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN},
@code{GL_TRIANGLES}, @code{GL_QUAD_STRIP}, @code{GL_QUADS}, and
Specifies the number of elements to be rendered.
@item @var{type}
-Specifies the type of the values in @var{indices}. Must be one of
+Specifies the type of the values in @var{indices}. Must be one of
@code{GL_UNSIGNED_BYTE}, @code{GL_UNSIGNED_SHORT}, or
@code{GL_UNSIGNED_INT}.
@end table
@code{glDrawRangeElements} is a restricted form of
-@code{glDrawElements}. @var{mode}, @var{start}, @var{end}, and
+@code{glDrawElements}. @var{mode}, @var{start}, @var{end}, and
@var{count} match the corresponding arguments to @code{glDrawElements},
with the additional constraint that all values in the arrays @var{count}
must lie between @var{start} and @var{end}, inclusive.
Implementations denote recommended maximum amounts of vertex and index
data, which may be queried by calling @code{glGet} with argument
-@code{GL_MAX_ELEMENTS_VERTICES} and @code{GL_MAX_ELEMENTS_INDICES}. If
+@code{GL_MAX_ELEMENTS_VERTICES} and @code{GL_MAX_ELEMENTS_INDICES}. If
@r{@var{end}-@var{start}+1} is greater than the value of
@code{GL_MAX_ELEMENTS_VERTICES}, or if @var{count} is greater than the
value of @code{GL_MAX_ELEMENTS_INDICES}, then the call may operate at
-reduced performance. There is no requirement that all vertices in the
-range @r{[@var{start},@var{end}]} be referenced. However, the
+reduced performance. There is no requirement that all vertices in the
+range @r{[@var{start},@var{end}]} be referenced. However, the
implementation may partially process unused vertices, reducing
performance from what could be achieved with an optimal index set.
When @code{glDrawRangeElements} is called, it uses @var{count}
sequential elements from an enabled array, starting at @var{start} to
-construct a sequence of geometric primitives. @var{mode} specifies what
+construct a sequence of geometric primitives. @var{mode} specifies what
kind of primitives are constructed, and how the array elements construct
-these primitives. If more than one array is enabled, each is used. If
+these primitives. If more than one array is enabled, each is used. If
@code{GL_VERTEX_ARRAY} is not enabled, no geometric primitives are
constructed.
Vertex attributes that are modified by @code{glDrawRangeElements} have
-an unspecified value after @code{glDrawRangeElements} returns. For
+an unspecified value after @code{glDrawRangeElements} returns. For
example, if @code{GL_COLOR_ARRAY} is enabled, the value of the current
-color is undefined after @code{glDrawRangeElements} executes. Attributes
+color is undefined after @code{glDrawRangeElements} executes. Attributes
that aren't modified maintain their previous values.
It is an error for indices to lie outside the range
@r{[@var{start},@var{end}]}, but implementations may not check for this
-situation. Such indices cause implementation-dependent behavior.
+situation. Such indices cause implementation-dependent behavior.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
value.
@table @asis
@item @var{stride}
-Specifies the byte offset between consecutive edge flags. If
+Specifies the byte offset between consecutive edge flags. If
@var{stride} is 0, the edge flags are understood to be tightly packed in
-the array. The initial value is 0.
+the array. The initial value is 0.
@item @var{pointer}
-Specifies a pointer to the first edge flag in the array. The initial
+Specifies a pointer to the first edge flag in the array. The initial
value is 0.
@end table
@code{glEdgeFlagPointer} specifies the location and data format of an
-array of boolean edge flags to use when rendering. @var{stride}
+array of boolean edge flags to use when rendering. @var{stride}
specifies the byte stride from one edge flag to the next, allowing
vertices and attributes to be packed into a single array or stored in
separate arrays.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while an edge flag array is specified,
@var{pointer} is treated as a byte offset into the buffer object's data
-store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
+store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
is saved as edge flag vertex array client-side state
(@code{GL_EDGE_FLAG_ARRAY_BUFFER_BINDING}).
To enable and disable the edge flag array, call
@code{glEnableClientState} and @code{glDisableClientState} with the
-argument @code{GL_EDGE_FLAG_ARRAY}. If enabled, the edge flag array is
+argument @code{GL_EDGE_FLAG_ARRAY}. If enabled, the edge flag array is
used when @code{glDrawArrays}, @code{glMultiDrawArrays},
@code{glDrawElements}, @code{glMultiDrawElements},
@code{glDrawRangeElements}, or @code{glArrayElement} is called.
@table @asis
@item @var{flag}
Specifies the current edge flag value, either @code{GL_TRUE} or
-@code{GL_FALSE}. The initial value is @code{GL_TRUE}.
+@code{GL_FALSE}. The initial value is @code{GL_TRUE}.
@end table
Each vertex of a polygon, separate triangle, or separate quadrilateral
specified between a @code{glBegin}/@code{glEnd} pair is marked as the
-start of either a boundary or nonboundary edge. If the current edge flag
-is true when the vertex is specified, the vertex is marked as the start
-of a boundary edge. Otherwise, the vertex is marked as the start of a
-nonboundary edge. @code{glEdgeFlag} sets the edge flag bit to
+start of either a boundary or nonboundary edge. If the current edge
+flag is true when the vertex is specified, the vertex is marked as the
+start of a boundary edge. Otherwise, the vertex is marked as the start
+of a nonboundary edge. @code{glEdgeFlag} sets the edge flag bit to
@code{GL_TRUE} if @var{flag} is @code{GL_TRUE} and to @code{GL_FALSE}
otherwise.
always marked as boundary, regardless of the value of the edge flag.
Boundary and nonboundary edge flags on vertices are significant only if
-@code{GL_POLYGON_MODE} is set to @code{GL_POINT} or @code{GL_LINE}. See
+@code{GL_POLYGON_MODE} is set to @code{GL_POINT} or @code{GL_LINE}. See
@code{glPolygonMode}.
@end deftypefun
@table @asis
@item @var{cap}
-Specifies the capability to enable. Symbolic constants
+Specifies the capability to enable. Symbolic constants
@code{GL_COLOR_ARRAY}, @code{GL_EDGE_FLAG_ARRAY},
@code{GL_FOG_COORD_ARRAY}, @code{GL_INDEX_ARRAY},
@code{GL_NORMAL_ARRAY}, @code{GL_SECONDARY_COLOR_ARRAY},
@end table
@code{glEnableClientState} and @code{glDisableClientState} enable or
-disable individual client-side capabilities. By default, all client-side
-capabilities are disabled. Both @code{glEnableClientState} and
-@code{glDisableClientState} take a single argument, @var{cap}, which can
-assume one of the following values:
+disable individual client-side capabilities. By default, all
+client-side capabilities are disabled. Both @code{glEnableClientState}
+and @code{glDisableClientState} take a single argument, @var{cap}, which
+can assume one of the following values:
@table @asis
@item @code{GL_COLOR_ARRAY}
rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glColorPointer}.
+@code{glMultiDrawElements} is called. See @code{glColorPointer}.
@item @code{GL_EDGE_FLAG_ARRAY}
If enabled, the edge flag array is enabled for writing and used during
rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glEdgeFlagPointer}.
+@code{glMultiDrawElements} is called. See @code{glEdgeFlagPointer}.
@item @code{GL_FOG_COORD_ARRAY}
If enabled, the fog coordinate array is enabled for writing and used
during rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glFogCoordPointer}.
+@code{glMultiDrawElements} is called. See @code{glFogCoordPointer}.
@item @code{GL_INDEX_ARRAY}
If enabled, the index array is enabled for writing and used during
rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glIndexPointer}.
+@code{glMultiDrawElements} is called. See @code{glIndexPointer}.
@item @code{GL_NORMAL_ARRAY}
If enabled, the normal array is enabled for writing and used during
rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glNormalPointer}.
+@code{glMultiDrawElements} is called. See @code{glNormalPointer}.
@item @code{GL_SECONDARY_COLOR_ARRAY}
If enabled, the secondary color array is enabled for writing and used
during rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glColorPointer}.
+@code{glMultiDrawElements} is called. See @code{glColorPointer}.
@item @code{GL_TEXTURE_COORD_ARRAY}
If enabled, the texture coordinate array is enabled for writing and used
during rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glTexCoordPointer}.
+@code{glMultiDrawElements} is called. See @code{glTexCoordPointer}.
@item @code{GL_VERTEX_ARRAY}
If enabled, the vertex array is enabled for writing and used during
rendering when @code{glArrayElement}, @code{glDrawArrays},
@code{glDrawElements},
@code{glDrawRangeElements}@code{glMultiDrawArrays}, or
-@code{glMultiDrawElements} is called. See @code{glVertexPointer}.
+@code{glMultiDrawElements} is called. See @code{glVertexPointer}.
@end table
@code{glEnableClientState} is not allowed between the execution of
@code{glBegin} and the corresponding @code{glEnd}, but an error may or
-may not be generated. If no error is generated, the behavior is
+may not be generated. If no error is generated, the behavior is
undefined.
@end deftypefun
@end table
@code{glEnableVertexAttribArray} enables the generic vertex attribute
-array specified by @var{index}. @code{glDisableVertexAttribArray}
-disables the generic vertex attribute array specified by @var{index}. By
+array specified by @var{index}. @code{glDisableVertexAttribArray}
+disables the generic vertex attribute array specified by @var{index}. By
default, all client-side capabilities are disabled, including all
-generic vertex attribute arrays. If enabled, the values in the generic
+generic vertex attribute arrays. If enabled, the values in the generic
vertex attribute array will be accessed and used for rendering when
calls are made to vertex array commands such as @code{glDrawArrays},
@code{glDrawElements}, @code{glDrawRangeElements},
@end table
@code{glEnable} and @code{glDisable} enable and disable various
-capabilities. Use @code{glIsEnabled} or @code{glGet} to determine the
-current setting of any capability. The initial value for each capability
-with the exception of @code{GL_DITHER} and @code{GL_MULTISAMPLE} is
-@code{GL_FALSE}. The initial value for @code{GL_DITHER} and
-@code{GL_MULTISAMPLE} is @code{GL_TRUE}.
+capabilities. Use @code{glIsEnabled} or @code{glGet} to determine the
+current setting of any capability. The initial value for each
+capability with the exception of @code{GL_DITHER} and
+@code{GL_MULTISAMPLE} is @code{GL_FALSE}. The initial value for
+@code{GL_DITHER} and @code{GL_MULTISAMPLE} is @code{GL_TRUE}.
Both @code{glEnable} and @code{glDisable} take a single argument,
@var{cap}, which can assume one of the following values:
@item @code{GL_ALPHA_TEST}
-If enabled, do alpha testing. See @code{glAlphaFunc}.
+If enabled, do alpha testing. See @code{glAlphaFunc}.
@item @code{GL_AUTO_NORMAL}
If enabled, generate normal vectors when either @code{GL_MAP2_VERTEX_3}
-or @code{GL_MAP2_VERTEX_4} is used to generate vertices. See
+or @code{GL_MAP2_VERTEX_4} is used to generate vertices. See
@code{glMap2}.
@item @code{GL_BLEND}
If enabled, blend the computed fragment color values with the values in
-the color buffers. See @code{glBlendFunc}.
+the color buffers. See @code{glBlendFunc}.
@item @code{GL_CLIP_PLANE}@var{i}
If enabled, apply the currently selected logical operation to the
-computed fragment color and color buffer values. See @code{glLogicOp}.
+computed fragment color and color buffer values. See @code{glLogicOp}.
@item @code{GL_COLOR_MATERIAL}
If enabled, have one or more material parameters track the current
-color. See @code{glColorMaterial}.
+color. See @code{glColorMaterial}.
@item @code{GL_COLOR_SUM}
If enabled and no fragment shader is active, add the secondary color
-value to the computed fragment color. See @code{glSecondaryColor}.
+value to the computed fragment color. See @code{glSecondaryColor}.
@item @code{GL_COLOR_TABLE}
If enabled, perform a color table lookup on the incoming RGBA color
-values. See @code{glColorTable}.
+values. See @code{glColorTable}.
@item @code{GL_CONVOLUTION_1D}
If enabled, perform a 1D convolution operation on incoming RGBA color
-values. See @code{glConvolutionFilter1D}.
+values. See @code{glConvolutionFilter1D}.
@item @code{GL_CONVOLUTION_2D}
If enabled, perform a 2D convolution operation on incoming RGBA color
-values. See @code{glConvolutionFilter2D}.
+values. See @code{glConvolutionFilter2D}.
@item @code{GL_CULL_FACE}
@item @code{GL_DEPTH_TEST}
-If enabled, do depth comparisons and update the depth buffer. Note that
+If enabled, do depth comparisons and update the depth buffer. Note that
even if the depth buffer exists and the depth mask is non-zero, the
-depth buffer is not updated if the depth test is disabled. See
+depth buffer is not updated if the depth test is disabled. See
@code{glDepthFunc} and @code{glDepthRange}.
@item @code{GL_DITHER}
If enabled and no fragment shader is active, blend a fog color into the
-post-texturing color. See @code{glFog}.
+post-texturing color. See @code{glFog}.
@item @code{GL_HISTOGRAM}
-If enabled, histogram incoming RGBA color values. See
+If enabled, histogram incoming RGBA color values. See
@code{glHistogram}.
@item @code{GL_INDEX_LOGIC_OP}
If enabled, apply the currently selected logical operation to the
-incoming index and color buffer indices. See @code{glLogicOp}.
+incoming index and color buffer indices. See @code{glLogicOp}.
@item @code{GL_LIGHT}@var{i}
If enabled, include light @var{i} in the evaluation of the lighting
-equation. See @code{glLightModel} and @code{glLight}.
+equation. See @code{glLightModel} and @code{glLight}.
@item @code{GL_LIGHTING}
If enabled and no vertex shader is active, use the current lighting
-parameters to compute the vertex color or index. Otherwise, simply
-associate the current color or index with each vertex. See
+parameters to compute the vertex color or index. Otherwise, simply
+associate the current color or index with each vertex. See
@code{glMaterial}, @code{glLightModel}, and @code{glLight}.
@item @code{GL_LINE_SMOOTH}
-If enabled, draw lines with correct filtering. Otherwise, draw aliased
-lines. See @code{glLineWidth}.
+If enabled, draw lines with correct filtering. Otherwise, draw aliased
+lines. See @code{glLineWidth}.
@item @code{GL_LINE_STIPPLE}
-If enabled, use the current line stipple pattern when drawing lines. See
+If enabled, use the current line stipple pattern when drawing lines. See
@code{glLineStipple}.
@item @code{GL_MAP1_COLOR_4}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
-@code{glEvalPoint1} generate RGBA values. See @code{glMap1}.
+@code{glEvalPoint1} generate RGBA values. See @code{glMap1}.
@item @code{GL_MAP1_INDEX}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
-@code{glEvalPoint1} generate color indices. See @code{glMap1}.
+@code{glEvalPoint1} generate color indices. See @code{glMap1}.
@item @code{GL_MAP1_NORMAL}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
-@code{glEvalPoint1} generate normals. See @code{glMap1}.
+@code{glEvalPoint1} generate normals. See @code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_1}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
-@code{glEvalPoint1} generate @var{s} texture coordinates. See
+@code{glEvalPoint1} generate @var{s} texture coordinates. See
@code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_2}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
@code{glEvalPoint1} generate @var{s}, @var{t}, and @var{r} texture
-coordinates. See @code{glMap1}.
+coordinates. See @code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_4}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
@code{glEvalPoint1} generate @var{s}, @var{t}, @var{r}, and @var{q}
-texture coordinates. See @code{glMap1}.
+texture coordinates. See @code{glMap1}.
@item @code{GL_MAP1_VERTEX_3}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
@code{glEvalPoint1} generate @var{x}, @var{y}, and @var{z} vertex
-coordinates. See @code{glMap1}.
+coordinates. See @code{glMap1}.
@item @code{GL_MAP1_VERTEX_4}
If enabled, calls to @code{glEvalCoord1}, @code{glEvalMesh1}, and
@code{glEvalPoint1} generate homogeneous @var{x}, @var{y}, @var{z}, and
-@var{w} vertex coordinates. See @code{glMap1}.
+@var{w} vertex coordinates. See @code{glMap1}.
@item @code{GL_MAP2_COLOR_4}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
-@code{glEvalPoint2} generate RGBA values. See @code{glMap2}.
+@code{glEvalPoint2} generate RGBA values. See @code{glMap2}.
@item @code{GL_MAP2_INDEX}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
-@code{glEvalPoint2} generate color indices. See @code{glMap2}.
+@code{glEvalPoint2} generate color indices. See @code{glMap2}.
@item @code{GL_MAP2_NORMAL}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
-@code{glEvalPoint2} generate normals. See @code{glMap2}.
+@code{glEvalPoint2} generate normals. See @code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_1}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
-@code{glEvalPoint2} generate @var{s} texture coordinates. See
+@code{glEvalPoint2} generate @var{s} texture coordinates. See
@code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_2}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
@code{glEvalPoint2} generate @var{s}, @var{t}, and @var{r} texture
-coordinates. See @code{glMap2}.
+coordinates. See @code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_4}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
@code{glEvalPoint2} generate @var{s}, @var{t}, @var{r}, and @var{q}
-texture coordinates. See @code{glMap2}.
+texture coordinates. See @code{glMap2}.
@item @code{GL_MAP2_VERTEX_3}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
@code{glEvalPoint2} generate @var{x}, @var{y}, and @var{z} vertex
-coordinates. See @code{glMap2}.
+coordinates. See @code{glMap2}.
@item @code{GL_MAP2_VERTEX_4}
If enabled, calls to @code{glEvalCoord2}, @code{glEvalMesh2}, and
@code{glEvalPoint2} generate homogeneous @var{x}, @var{y}, @var{z}, and
-@var{w} vertex coordinates. See @code{glMap2}.
+@var{w} vertex coordinates. See @code{glMap2}.
@item @code{GL_MINMAX}
If enabled, compute the minimum and maximum values of incoming RGBA
-color values. See @code{glMinmax}.
+color values. See @code{glMinmax}.
@item @code{GL_MULTISAMPLE}
If enabled, use multiple fragment samples in computing the final color
-of a pixel. See @code{glSampleCoverage}.
+of a pixel. See @code{glSampleCoverage}.
@item @code{GL_NORMALIZE}
If enabled and no vertex shader is active, normal vectors are normalized
-to unit length after transformation and before lighting. This method is
-generally less efficient than @code{GL_RESCALE_NORMAL}. See
+to unit length after transformation and before lighting. This method is
+generally less efficient than @code{GL_RESCALE_NORMAL}. See
@code{glNormal} and @code{glNormalPointer}.
@item @code{GL_POINT_SMOOTH}
-If enabled, draw points with proper filtering. Otherwise, draw aliased
-points. See @code{glPointSize}.
+If enabled, draw points with proper filtering. Otherwise, draw aliased
+points. See @code{glPointSize}.
@item @code{GL_POINT_SPRITE}
If enabled, calculate texture coordinates for points based on texture
-environment and point parameter settings. Otherwise texture coordinates
+environment and point parameter settings. Otherwise texture coordinates
are constant across points.
@item @code{GL_POLYGON_OFFSET_FILL}
If enabled, and if the polygon is rendered in @code{GL_FILL} mode, an
offset is added to depth values of a polygon's fragments before the
-depth comparison is performed. See @code{glPolygonOffset}.
+depth comparison is performed. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_LINE}
If enabled, and if the polygon is rendered in @code{GL_LINE} mode, an
offset is added to depth values of a polygon's fragments before the
-depth comparison is performed. See @code{glPolygonOffset}.
+depth comparison is performed. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_POINT}
If enabled, an offset is added to depth values of a polygon's fragments
before the depth comparison is performed, if the polygon is rendered in
-@code{GL_POINT} mode. See @code{glPolygonOffset}.
+@code{GL_POINT} mode. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_SMOOTH}
-If enabled, draw polygons with proper filtering. Otherwise, draw aliased
-polygons. For correct antialiased polygons, an alpha buffer is needed
-and the polygons must be sorted front to back.
+If enabled, draw polygons with proper filtering. Otherwise, draw
+aliased polygons. For correct antialiased polygons, an alpha buffer is
+needed and the polygons must be sorted front to back.
@item @code{GL_POLYGON_STIPPLE}
If enabled, use the current polygon stipple pattern when rendering
-polygons. See @code{glPolygonStipple}.
+polygons. See @code{glPolygonStipple}.
@item @code{GL_POST_COLOR_MATRIX_COLOR_TABLE}
If enabled, perform a color table lookup on RGBA color values after
-color matrix transformation. See @code{glColorTable}.
+color matrix transformation. See @code{glColorTable}.
@item @code{GL_POST_CONVOLUTION_COLOR_TABLE}
If enabled, perform a color table lookup on RGBA color values after
-convolution. See @code{glColorTable}.
+convolution. See @code{glColorTable}.
@item @code{GL_RESCALE_NORMAL}
If enabled and no vertex shader is active, normal vectors are scaled
after transformation and before lighting by a factor computed from the
-modelview matrix. If the modelview matrix scales space uniformly, this
-has the effect of restoring the transformed normal to unit length. This
-method is generally more efficient than @code{GL_NORMALIZE}. See
+modelview matrix. If the modelview matrix scales space uniformly, this
+has the effect of restoring the transformed normal to unit length. This
+method is generally more efficient than @code{GL_NORMALIZE}. See
@code{glNormal} and @code{glNormalPointer}.
@item @code{GL_SAMPLE_ALPHA_TO_COVERAGE}
If enabled, compute a temporary coverage value where each bit is
-determined by the alpha value at the corresponding sample location. The
+determined by the alpha value at the corresponding sample location. The
temporary coverage value is then ANDed with the fragment coverage value.
@item @code{GL_SAMPLE_ALPHA_TO_ONE}
If enabled, the fragment's coverage is ANDed with the temporary coverage
-value. If @code{GL_SAMPLE_COVERAGE_INVERT} is set to @code{GL_TRUE},
-invert the coverage value. See @code{glSampleCoverage}.
+value. If @code{GL_SAMPLE_COVERAGE_INVERT} is set to @code{GL_TRUE},
+invert the coverage value. See @code{glSampleCoverage}.
@item @code{GL_SEPARABLE_2D}
If enabled, perform a two-dimensional convolution operation using a
-separable convolution filter on incoming RGBA color values. See
+separable convolution filter on incoming RGBA color values. See
@code{glSeparableFilter2D}.
@item @code{GL_SCISSOR_TEST}
@item @code{GL_STENCIL_TEST}
-If enabled, do stencil testing and update the stencil buffer. See
+If enabled, do stencil testing and update the stencil buffer. See
@code{glStencilFunc} and @code{glStencilOp}.
@item @code{GL_TEXTURE_1D}
If enabled and no fragment shader is active, one-dimensional texturing
is performed (unless two- or three-dimensional or cube-mapped texturing
-is also enabled). See @code{glTexImage1D}.
+is also enabled). See @code{glTexImage1D}.
@item @code{GL_TEXTURE_2D}
If enabled and no fragment shader is active, two-dimensional texturing
is performed (unless three-dimensional or cube-mapped texturing is also
-enabled). See @code{glTexImage2D}.
+enabled). See @code{glTexImage2D}.
@item @code{GL_TEXTURE_3D}
If enabled and no fragment shader is active, three-dimensional texturing
-is performed (unless cube-mapped texturing is also enabled). See
+is performed (unless cube-mapped texturing is also enabled). See
@code{glTexImage3D}.
@item @code{GL_TEXTURE_CUBE_MAP}
If enabled and no fragment shader is active, cube-mapped texturing is
-performed. See @code{glTexImage2D}.
+performed. See @code{glTexImage2D}.
@item @code{GL_TEXTURE_GEN_Q}
If enabled and no vertex shader is active, the @var{q} texture
coordinate is computed using the texture generation function defined
-with @code{glTexGen}. Otherwise, the current @var{q} texture coordinate
-is used. See @code{glTexGen}.
+with @code{glTexGen}. Otherwise, the current @var{q} texture coordinate
+is used. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_R}
If enabled and no vertex shader is active, the @var{r} texture
coordinate is computed using the texture generation function defined
-with @code{glTexGen}. Otherwise, the current @var{r} texture coordinate
-is used. See @code{glTexGen}.
+with @code{glTexGen}. Otherwise, the current @var{r} texture coordinate
+is used. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_S}
If enabled and no vertex shader is active, the @var{s} texture
coordinate is computed using the texture generation function defined
-with @code{glTexGen}. Otherwise, the current @var{s} texture coordinate
-is used. See @code{glTexGen}.
+with @code{glTexGen}. Otherwise, the current @var{s} texture coordinate
+is used. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_T}
If enabled and no vertex shader is active, the @var{t} texture
coordinate is computed using the texture generation function defined
-with @code{glTexGen}. Otherwise, the current @var{t} texture coordinate
-is used. See @code{glTexGen}.
+with @code{glTexGen}. Otherwise, the current @var{t} texture coordinate
+is used. See @code{glTexGen}.
@item @code{GL_VERTEX_PROGRAM_POINT_SIZE}
If enabled and a vertex shader is active, it specifies that the GL will
choose between front and back colors based on the polygon's face
-direction of which the vertex being shaded is a part. It has no effect
+direction of which the vertex being shaded is a part. It has no effect
on points or lines.
@end table
@item @var{v}
Specifies a value that is the domain coordinate @r{@var{v}} to the basis
-function defined in a previous @code{glMap2} command. This argument is
+function defined in a previous @code{glMap2} command. This argument is
not present in a @code{glEvalCoord1} command.
@end table
@code{glEvalCoord1} evaluates enabled one-dimensional maps at argument
-@var{u}. @code{glEvalCoord2} does the same for two-dimensional maps
-using two domain values, @var{u} and @var{v}. To define a map, call
+@var{u}. @code{glEvalCoord2} does the same for two-dimensional maps
+using two domain values, @var{u} and @var{v}. To define a map, call
@code{glMap1} and @code{glMap2}; to enable and disable it, call
@code{glEnable} and @code{glDisable}.
When one of the @code{glEvalCoord} commands is issued, all currently
-enabled maps of the indicated dimension are evaluated. Then, for each
+enabled maps of the indicated dimension are evaluated. Then, for each
enabled map, it is as if the corresponding GL command had been issued
-with the computed value. That is, if @code{GL_MAP1_INDEX} or
+with the computed value. That is, if @code{GL_MAP1_INDEX} or
@code{GL_MAP2_INDEX} is enabled, a @code{glIndex} command is simulated.
If @code{GL_MAP1_COLOR_4} or @code{GL_MAP2_COLOR_4} is enabled, a
-@code{glColor} command is simulated. If @code{GL_MAP1_NORMAL} or
+@code{glColor} command is simulated. If @code{GL_MAP1_NORMAL} or
@code{GL_MAP2_NORMAL} is enabled, a normal vector is produced, and if
any of @code{GL_MAP1_TEXTURE_COORD_1}, @code{GL_MAP1_TEXTURE_COORD_2},
@code{GL_MAP1_TEXTURE_COORD_3}, @code{GL_MAP1_TEXTURE_COORD_4},
For color, color index, normal, and texture coordinates the GL uses
evaluated values instead of current values for those evaluations that
are enabled, and current values otherwise, However, the evaluated values
-do not update the current values. Thus, if @code{glVertex} commands are
+do not update the current values. Thus, if @code{glVertex} commands are
interspersed with @code{glEvalCoord} commands, the color, normal, and
texture coordinates associated with the @code{glVertex} commands are not
affected by the values generated by the @code{glEvalCoord} commands, but
only by the most recent @code{glColor}, @code{glIndex}, @code{glNormal},
and @code{glTexCoord} commands.
-No commands are issued for maps that are not enabled. If more than one
+No commands are issued for maps that are not enabled. If more than one
texture evaluation is enabled for a particular dimension (for example,
@code{GL_MAP2_TEXTURE_COORD_1} and @code{GL_MAP2_TEXTURE_COORD_2}), then
only the evaluation of the map that produces the larger number of
coordinates (in this case, @code{GL_MAP2_TEXTURE_COORD_2}) is carried
-out. @code{GL_MAP1_VERTEX_4} overrides @code{GL_MAP1_VERTEX_3}, and
+out. @code{GL_MAP1_VERTEX_4} overrides @code{GL_MAP1_VERTEX_3}, and
@code{GL_MAP2_VERTEX_4} overrides @code{GL_MAP2_VERTEX_3}, in the same
-manner. If neither a three- nor a four-component vertex map is enabled
+manner. If neither a three- nor a four-component vertex map is enabled
for the specified dimension, the @code{glEvalCoord} command is ignored.
If you have enabled automatic normal generation, by calling
@code{glEnable} with argument @code{GL_AUTO_NORMAL}, @code{glEvalCoord2}
generates surface normals analytically, regardless of the contents or
-enabling of the @code{GL_MAP2_NORMAL} map. Let
+enabling of the @code{GL_MAP2_NORMAL} map. Let
@r{@code{m}=∂@code{p},/∂@var{u},,×∂@code{p},/∂@var{v},,}
@r{@code{n}=@code{m}/∥@code{m},∥,}
If automatic normal generation is disabled, the corresponding normal map
-@code{GL_MAP2_NORMAL}, if enabled, is used to produce a normal. If
+@code{GL_MAP2_NORMAL}, if enabled, is used to produce a normal. If
neither automatic normal generation nor a normal map is enabled, no
normal is generated for @code{glEvalCoord2} commands.
@table @asis
@item @var{mode}
In @code{glEvalMesh1}, specifies whether to compute a one-dimensional
-mesh of points or lines. Symbolic constants @code{GL_POINT} and
+mesh of points or lines. Symbolic constants @code{GL_POINT} and
@code{GL_LINE} are accepted.
@item @var{i1}
generate and evaluate a series of evenly-spaced map domain values.
@code{glEvalMesh} steps through the integer domain of a one- or
two-dimensional grid, whose range is the domain of the evaluation maps
-specified by @code{glMap1} and @code{glMap2}. @var{mode} determines
+specified by @code{glMap1} and @code{glMap2}. @var{mode} determines
whether the resulting vertices are connected as points, lines, or filled
polygons.
@r{Δ@var{u}=(@var{u}_2-@var{u}_1,)/@var{n}}
and @r{@var{n}}, @r{@var{u}_1}, and @r{@var{u}_2} are the arguments to
-the most recent @code{glMapGrid1} command. @var{type} is
+the most recent @code{glMapGrid1} command. @var{type} is
@code{GL_POINTS} if @var{mode} is @code{GL_POINT}, or @code{GL_LINES} if
@var{mode} is @code{GL_LINE}.
where @r{@var{n}}, @r{@var{u}_1}, @r{@var{u}_2}, @r{@var{m}},
@r{@var{v}_1}, and @r{@var{v}_2} are the arguments to the most recent
-@code{glMapGrid2} command. Then, if @var{mode} is @code{GL_FILL}, the
+@code{glMapGrid2} command. Then, if @var{mode} is @code{GL_FILL}, the
@code{glEvalMesh2} command is equivalent to:
@code{glMapGrid} and @code{glEvalMesh} are used in tandem to efficiently
generate and evaluate a series of evenly spaced map domain values.
@code{glEvalPoint} can be used to evaluate a single grid point in the
-same gridspace that is traversed by @code{glEvalMesh}. Calling
+same gridspace that is traversed by @code{glEvalMesh}. Calling
@code{glEvalPoint1} is equivalent to calling where
@r{Δ@var{u}=(@var{u}_2-@var{u}_1,)/@var{n}}
@end example
and @r{@var{n}}, @r{@var{u}_1}, and @r{@var{u}_2} are the arguments to
-the most recent @code{glMapGrid1} command. The one absolute numeric
+the most recent @code{glMapGrid1} command. The one absolute numeric
requirement is that if @r{@var{i}=@var{n}}, then the value computed from
@r{@var{i}·Δ@var{u}+@var{u}_1} is exactly @r{@var{u}_2}.
where @r{@var{n}}, @r{@var{u}_1}, @r{@var{u}_2}, @r{@var{m}},
@r{@var{v}_1}, and @r{@var{v}_2} are the arguments to the most recent
-@code{glMapGrid2} command. Then the @code{glEvalPoint2} command is
+@code{glMapGrid2} command. Then the @code{glEvalPoint2} command is
equivalent to calling The only absolute numeric requirements are that if
@r{@var{i}=@var{n}}, then the value computed from
@r{@var{i}·Δ@var{u}+@var{u}_1} is exactly @r{@var{u}_2}, and if
@item @var{type}
Specifies a symbolic constant that describes the information that will
-be returned for each vertex. @code{GL_2D}, @code{GL_3D},
+be returned for each vertex. @code{GL_2D}, @code{GL_3D},
@code{GL_3D_COLOR}, @code{GL_3D_COLOR_TEXTURE}, and
@code{GL_4D_COLOR_TEXTURE} are accepted.
@end table
-The @code{glFeedbackBuffer} function controls feedback. Feedback, like
-selection, is a GL mode. The mode is selected by calling
-@code{glRenderMode} with @code{GL_FEEDBACK}. When the GL is in feedback
-mode, no pixels are produced by rasterization. Instead, information
+The @code{glFeedbackBuffer} function controls feedback. Feedback, like
+selection, is a GL mode. The mode is selected by calling
+@code{glRenderMode} with @code{GL_FEEDBACK}. When the GL is in feedback
+mode, no pixels are produced by rasterization. Instead, information
about primitives that would have been rasterized is fed back to the
application using the GL.
@code{glFeedbackBuffer} has three arguments: @var{buffer} is a pointer
to an array of floating-point values into which feedback information is
-placed. @var{size} indicates the size of the array. @var{type} is a
+placed. @var{size} indicates the size of the array. @var{type} is a
symbolic constant describing the information that is fed back for each
-vertex. @code{glFeedbackBuffer} must be issued before feedback mode is
+vertex. @code{glFeedbackBuffer} must be issued before feedback mode is
enabled (by calling @code{glRenderMode} with argument
-@code{GL_FEEDBACK}). Setting @code{GL_FEEDBACK} without establishing the
-feedback buffer, or calling @code{glFeedbackBuffer} while the GL is in
-feedback mode, is an error.
+@code{GL_FEEDBACK}). Setting @code{GL_FEEDBACK} without establishing
+the feedback buffer, or calling @code{glFeedbackBuffer} while the GL is
+in feedback mode, is an error.
When @code{glRenderMode} is called while in feedback mode, it returns
the number of entries placed in the feedback array and resets the
-feedback array pointer to the base of the feedback buffer. The returned
-value never exceeds @var{size}. If the feedback data required more room
+feedback array pointer to the base of the feedback buffer. The returned
+value never exceeds @var{size}. If the feedback data required more room
than was available in @var{buffer}, @code{glRenderMode} returns a
-negative value. To take the GL out of feedback mode, call
+negative value. To take the GL out of feedback mode, call
@code{glRenderMode} with a parameter value other than
@code{GL_FEEDBACK}.
While in feedback mode, each primitive, bitmap, or pixel rectangle that
would be rasterized generates a block of values that are copied into the
-feedback array. If doing so would cause the number of entries to exceed
+feedback array. If doing so would cause the number of entries to exceed
the maximum, the block is partially written so as to fill the array (if
-there is any room left at all), and an overflow flag is set. Each block
+there is any room left at all), and an overflow flag is set. Each block
begins with a code indicating the primitive type, followed by values
-that describe the primitive's vertices and associated data. Entries are
-also written for bitmaps and pixel rectangles. Feedback occurs after
+that describe the primitive's vertices and associated data. Entries are
+also written for bitmaps and pixel rectangles. Feedback occurs after
polygon culling and @code{glPolygonMode} interpretation of polygons has
taken place, so polygons that are culled are not returned in the
-feedback buffer. It can also occur after polygons with more than three
+feedback buffer. It can also occur after polygons with more than three
edges are broken up into triangles, if the GL implementation renders
polygons by performing this decomposition.
The @code{glPassThrough} command can be used to insert a marker into the
-feedback buffer. See @code{glPassThrough}.
+feedback buffer. See @code{glPassThrough}.
Following is the grammar for the blocks of values written into the
-feedback buffer. Each primitive is indicated with a unique identifying
-value followed by some number of vertices. Polygon entries include an
-integer value indicating how many vertices follow. A vertex is fed back
+feedback buffer. Each primitive is indicated with a unique identifying
+value followed by some number of vertices. Polygon entries include an
+integer value indicating how many vertices follow. A vertex is fed back
as some number of floating-point values, as determined by @var{type}.
Colors are fed back as four values in RGBA mode and one value in color
index mode.
@code{GL_DRAW_PIXEL_TOKEN}, @code{GL_COPY_PIXEL_TOKEN} and
@code{GL_PASS_THROUGH_TOKEN} are symbolic floating-point constants.
@code{GL_LINE_RESET_TOKEN} is returned whenever the line stipple pattern
-is reset. The data returned as a vertex depends on the feedback
+is reset. The data returned as a vertex depends on the feedback
@var{type}.
The following table gives the correspondence between @var{type} and the
-number of values per vertex. @var{k} is 1 in color index mode and 4 in
+number of values per vertex. @var{k} is 1 in color index mode and 4 in
RGBA mode.
@end table
Feedback vertex coordinates are in window coordinates, except @var{w},
-which is in clip coordinates. Feedback colors are lighted, if lighting
-is enabled. Feedback texture coordinates are generated, if texture
-coordinate generation is enabled. They are always transformed by the
+which is in clip coordinates. Feedback colors are lighted, if lighting
+is enabled. Feedback texture coordinates are generated, if texture
+coordinate generation is enabled. They are always transformed by the
texture matrix.
@code{GL_INVALID_ENUM} is generated if @var{type} is not an accepted
Block until all GL execution is complete.
@code{glFinish} does not return until the effects of all previously
-called GL commands are complete. Such effects include all changes to GL
+called GL commands are complete. Such effects include all changes to GL
state, all changes to connection state, and all changes to the frame
buffer contents.
Different GL implementations buffer commands in several different
locations, including network buffers and the graphics accelerator
-itself. @code{glFlush} empties all of these buffers, causing all issued
+itself. @code{glFlush} empties all of these buffers, causing all issued
commands to be executed as quickly as they are accepted by the actual
-rendering engine. Though this execution may not be completed in any
+rendering engine. Though this execution may not be completed in any
particular time period, it does complete in finite time.
Because any GL program might be executed over a network, or on an
accelerator that buffers commands, all programs should call
@code{glFlush} whenever they count on having all of their previously
-issued commands completed. For example, call @code{glFlush} before
+issued commands completed. For example, call @code{glFlush} before
waiting for user input that depends on the generated image.
@code{GL_INVALID_OPERATION} is generated if @code{glFlush} is executed
@table @asis
@item @var{type}
-Specifies the data type of each fog coordinate. Symbolic constants
-@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
+Specifies the data type of each fog coordinate. Symbolic constants
+@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
@code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive fog coordinates. If
+Specifies the byte offset between consecutive fog coordinates. If
@var{stride} is 0, the array elements are understood to be tightly
-packed. The initial value is 0.
+packed. The initial value is 0.
@item @var{pointer}
Specifies a pointer to the first coordinate of the first fog coordinate
-in the array. The initial value is 0.
+in the array. The initial value is 0.
@end table
@code{glFogCoordPointer} specifies the location and data format of an
-array of fog coordinates to use when rendering. @var{type} specifies the
-data type of each fog coordinate, and @var{stride} specifies the byte
-stride from one fog coordinate to the next, allowing vertices and
+array of fog coordinates to use when rendering. @var{type} specifies
+the data type of each fog coordinate, and @var{stride} specifies the
+byte stride from one fog coordinate to the next, allowing vertices and
attributes to be packed into a single array or stored in separate
arrays.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a fog coordinate array is
specified, @var{pointer} is treated as a byte offset into the buffer
-object's data store. Also, the buffer object binding
+object's data store. Also, the buffer object binding
(@code{GL_ARRAY_BUFFER_BINDING}) is saved as fog coordinate vertex array
client-side state (@code{GL_FOG_COORD_ARRAY_BUFFER_BINDING}).
To enable and disable the fog coordinate array, call
@code{glEnableClientState} and @code{glDisableClientState} with the
-argument @code{GL_FOG_COORD_ARRAY}. If enabled, the fog coordinate array
-is used when @code{glDrawArrays}, @code{glMultiDrawArrays},
+argument @code{GL_FOG_COORD_ARRAY}. If enabled, the fog coordinate
+array is used when @code{glDrawArrays}, @code{glMultiDrawArrays},
@code{glDrawElements}, @code{glMultiDrawElements},
@code{glDrawRangeElements}, or @code{glArrayElement} is called.
@end table
@code{glFogCoord} specifies the fog coordinate that is associated with
-each vertex and the current raster position. The value specified is
+each vertex and the current raster position. The value specified is
interpolated and used in computing the fog color (see @code{glFog}).
@end deftypefun
@table @asis
@item @var{pname}
-Specifies a single-valued fog parameter. @code{GL_FOG_MODE},
+Specifies a single-valued fog parameter. @code{GL_FOG_MODE},
@code{GL_FOG_DENSITY}, @code{GL_FOG_START}, @code{GL_FOG_END},
@code{GL_FOG_INDEX}, and @code{GL_FOG_COORD_SRC} are accepted.
@end table
-Fog is initially disabled. While enabled, fog affects rasterized
-geometry, bitmaps, and pixel blocks, but not buffer clear operations. To
+Fog is initially disabled. While enabled, fog affects rasterized
+geometry, bitmaps, and pixel blocks, but not buffer clear operations. To
enable and disable fog, call @code{glEnable} and @code{glDisable} with
argument @code{GL_FOG}.
@code{glFog} assigns the value or values in @var{params} to the fog
-parameter specified by @var{pname}. The following values are accepted
+parameter specified by @var{pname}. The following values are accepted
for @var{pname}:
@table @asis
@var{params} is a single integer or floating-point value that specifies
the equation to be used to compute the fog blend factor, @r{@var{f}}.
Three symbolic constants are accepted: @code{GL_LINEAR}, @code{GL_EXP},
-and @code{GL_EXP2}. The equations corresponding to these symbolic
-constants are defined below. The initial fog mode is @code{GL_EXP}.
+and @code{GL_EXP2}. The equations corresponding to these symbolic
+constants are defined below. The initial fog mode is @code{GL_EXP}.
@item @code{GL_FOG_DENSITY}
@var{params} is a single integer or floating-point value that specifies
@r{@var{density}}, the fog density used in both exponential fog
-equations. Only nonnegative densities are accepted. The initial fog
+equations. Only nonnegative densities are accepted. The initial fog
density is 1.
@item @code{GL_FOG_START}
@var{params} is a single integer or floating-point value that specifies
-@r{@var{start}}, the near distance used in the linear fog equation. The
+@r{@var{start}}, the near distance used in the linear fog equation. The
initial near distance is 0.
@item @code{GL_FOG_END}
@var{params} is a single integer or floating-point value that specifies
-@r{@var{end}}, the far distance used in the linear fog equation. The
+@r{@var{end}}, the far distance used in the linear fog equation. The
initial far distance is 1.
@item @code{GL_FOG_INDEX}
@var{params} is a single integer or floating-point value that specifies
-@r{@var{i}_@var{f}}, the fog color index. The initial fog index is 0.
+@r{@var{i}_@var{f}}, the fog color index. The initial fog index is 0.
@item @code{GL_FOG_COLOR}
@var{params} contains four integer or floating-point values that specify
-@r{@var{C}_@var{f}}, the fog color. Integer values are mapped linearly
+@r{@var{C}_@var{f}}, the fog color. Integer values are mapped linearly
such that the most positive representable value maps to 1.0, and the
-most negative representable value maps to @r{-1.0}. Floating-point
-values are mapped directly. After conversion, all color components are
-clamped to the range @r{[0,1]}. The initial fog color is (0, 0, 0, 0).
+most negative representable value maps to @r{-1.0}. Floating-point
+values are mapped directly. After conversion, all color components are
+clamped to the range @r{[0,1]}. The initial fog color is (0, 0, 0, 0).
@item @code{GL_FOG_COORD_SRC}
@var{params} contains either of the following symbolic constants:
-@code{GL_FOG_COORD} or @code{GL_FRAGMENT_DEPTH}. @code{GL_FOG_COORD}
+@code{GL_FOG_COORD} or @code{GL_FRAGMENT_DEPTH}. @code{GL_FOG_COORD}
specifies that the current fog coordinate should be used as distance
-value in the fog color computation. @code{GL_FRAGMENT_DEPTH} specifies
+value in the fog color computation. @code{GL_FRAGMENT_DEPTH} specifies
that the current fragment depth should be used as distance value in the
fog computation.
@end table
Fog blends a fog color with each rasterized pixel fragment's
-post-texturing color using a blending factor @r{@var{f}}. Factor
+post-texturing color using a blending factor @r{@var{f}}. Factor
@r{@var{f}} is computed in one of three ways, depending on the fog mode.
Let @r{@var{c}} be either the distance in eye coordinate from the origin
(in the case that the @code{GL_FOG_COORD_SRC} is
@code{GL_FRAGMENT_DEPTH}) or the current fog coordinate (in the case
-that @code{GL_FOG_COORD_SRC} is @code{GL_FOG_COORD}). The equation for
+that @code{GL_FOG_COORD_SRC} is @code{GL_FOG_COORD}). The equation for
@code{GL_LINEAR} fog is
@r{@var{f}=@var{end}-@var{c},/@var{end}-@var{start},}
@r{@var{f}=@var{e}^-(@var{density}·@var{c},),^2}
Regardless of the fog mode, @r{@var{f}} is clamped to the range
-@r{[0,1]} after it is computed. Then, if the GL is in RGBA color mode,
+@r{[0,1]} after it is computed. Then, if the GL is in RGBA color mode,
the fragment's red, green, and blue colors, represented by
@r{@var{C}_@var{r}}, are replaced by
@table @asis
@item @var{mode}
-Specifies the orientation of front-facing polygons. @code{GL_CW} and
-@code{GL_CCW} are accepted. The initial value is @code{GL_CCW}.
+Specifies the orientation of front-facing polygons. @code{GL_CW} and
+@code{GL_CCW} are accepted. The initial value is @code{GL_CCW}.
@end table
In a scene composed entirely of opaque closed surfaces, back-facing
-polygons are never visible. Eliminating these invisible polygons has the
-obvious benefit of speeding up the rendering of the image. To enable and
-disable elimination of back-facing polygons, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_CULL_FACE}.
+polygons are never visible. Eliminating these invisible polygons has
+the obvious benefit of speeding up the rendering of the image. To
+enable and disable elimination of back-facing polygons, call
+@code{glEnable} and @code{glDisable} with argument @code{GL_CULL_FACE}.
The projection of a polygon to window coordinates is said to have
clockwise winding if an imaginary object following the path from its
first vertex, its second vertex, and so on, to its last vertex, and
finally back to its first vertex, moves in a clockwise direction about
-the interior of the polygon. The polygon's winding is said to be
+the interior of the polygon. The polygon's winding is said to be
counterclockwise if the imaginary object following the same path moves
in a counterclockwise direction about the interior of the polygon.
@code{glFrontFace} specifies whether polygons with clockwise winding in
window coordinates, or counterclockwise winding in window coordinates,
-are taken to be front-facing. Passing @code{GL_CCW} to @var{mode}
+are taken to be front-facing. Passing @code{GL_CCW} to @var{mode}
selects counterclockwise polygons as front-facing; @code{GL_CW} selects
-clockwise polygons as front-facing. By default, counterclockwise
+clockwise polygons as front-facing. By default, counterclockwise
polygons are taken to be front-facing.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
@item @var{nearVal}
@itemx @var{farVal}
-Specify the distances to the near and far depth clipping planes. Both
+Specify the distances to the near and far depth clipping planes. Both
distances must be positive.
@end table
@code{glFrustum} describes a perspective matrix that produces a
-perspective projection. The current matrix (see @code{glMatrixMode}) is
+perspective projection. The current matrix (see @code{glMatrixMode}) is
multiplied by this matrix and the result replaces the current matrix, as
if @code{glMultMatrix} were called with the following matrix as its
argument:
@r{(@var{right},@var{top}-@var{nearVal})} specify the points on the near
clipping plane that are mapped to the lower left and upper right corners
of the window, assuming that the eye is located at (0, 0, 0).
-@r{-@var{farVal}} specifies the location of the far clipping plane. Both
+@r{-@var{farVal}} specifies the location of the far clipping plane. Both
@var{nearVal} and @var{farVal} must be positive.
Use @code{glPushMatrix} and @code{glPopMatrix} to save and restore the
@end table
@code{glGenBuffers} returns @var{n} buffer object names in
-@var{buffers}. There is no guarantee that the names form a contiguous
+@var{buffers}. There is no guarantee that the names form a contiguous
set of integers; however, it is guaranteed that none of the returned
names was in use immediately before the call to @code{glGenBuffers}.
@end table
-@code{glGenLists} has one argument, @var{range}. It returns an integer
+@code{glGenLists} has one argument, @var{range}. It returns an integer
@var{n} such that @var{range} contiguous empty display lists, named
@r{@var{n}}, @r{@var{n}+1}, @r{@var{...}}, @r{@var{n}+@var{range}-1},
-are created. If @var{range} is 0, if there is no group of @var{range}
+are created. If @var{range} is 0, if there is no group of @var{range}
contiguous names available, or if any error is generated, no display
lists are generated, and 0 is returned.
@end table
@code{glGetActiveAttrib} returns information about an active attribute
-variable in the program object specified by @var{program}. The number of
-active attributes can be obtained by calling @code{glGetProgram} with
-the value @code{GL_ACTIVE_ATTRIBUTES}. A value of 0 for @var{index}
-selects the first active attribute variable. Permissible values for
+variable in the program object specified by @var{program}. The number
+of active attributes can be obtained by calling @code{glGetProgram} with
+the value @code{GL_ACTIVE_ATTRIBUTES}. A value of 0 for @var{index}
+selects the first active attribute variable. Permissible values for
@var{index} range from 0 to the number of active attribute variables
minus 1.
A vertex shader may use either built-in attribute variables,
-user-defined attribute variables, or both. Built-in attribute variables
+user-defined attribute variables, or both. Built-in attribute variables
have a prefix of "gl_" and reference conventional OpenGL vertex
attribtes (e.g., @var{gl_Vertex}, @var{gl_Normal}, etc., see the OpenGL
Shading Language specification for a complete list.) User-defined
attribute variables have arbitrary names and obtain their values through
-numbered generic vertex attributes. An attribute variable (either
+numbered generic vertex attributes. An attribute variable (either
built-in or user-defined) is considered active if it is determined
during the link operation that it may be accessed during program
-execution. Therefore, @var{program} should have previously been the
+execution. Therefore, @var{program} should have previously been the
target of a call to @code{glLinkProgram}, but it is not necessary for it
to have been linked successfully.
The size of the character buffer required to store the longest attribute
variable name in @var{program} can be obtained by calling
@code{glGetProgram} with the value
-@code{GL_ACTIVE_ATTRIBUTE_MAX_LENGTH}. This value should be used to
+@code{GL_ACTIVE_ATTRIBUTE_MAX_LENGTH}. This value should be used to
allocate a buffer of sufficient size to store the returned attribute
-name. The size of this character buffer is passed in @var{bufSize}, and
+name. The size of this character buffer is passed in @var{bufSize}, and
a pointer to this character buffer is passed in @var{name}.
@code{glGetActiveAttrib} returns the name of the attribute variable
indicated by @var{index}, storing it in the character buffer specified
-by @var{name}. The string returned will be null terminated. The actual
+by @var{name}. The string returned will be null terminated. The actual
number of characters written into this buffer is returned in
@var{length}, and this count does not include the null termination
-character. If the length of the returned string is not required, a value
-of @code{NULL} can be passed in the @var{length} argument.
+character. If the length of the returned string is not required, a
+value of @code{NULL} can be passed in the @var{length} argument.
The @var{type} argument will return a pointer to the attribute
-variable's data type. The symbolic constants @code{GL_FLOAT},
+variable's data type. The symbolic constants @code{GL_FLOAT},
@code{GL_FLOAT_VEC2}, @code{GL_FLOAT_VEC3}, @code{GL_FLOAT_VEC4},
@code{GL_FLOAT_MAT2}, @code{GL_FLOAT_MAT3}, @code{GL_FLOAT_MAT4},
@code{GL_FLOAT_MAT2x3}, @code{GL_FLOAT_MAT2x4}, @code{GL_FLOAT_MAT3x2},
@code{GL_FLOAT_MAT3x4}, @code{GL_FLOAT_MAT4x2}, or
-@code{GL_FLOAT_MAT4x3} may be returned. The @var{size} argument will
+@code{GL_FLOAT_MAT4x3} may be returned. The @var{size} argument will
return the size of the attribute, in units of the type returned in
@var{type}.
user-defined attribute variable names.
This function will return as much information as it can about the
-specified active attribute variable. If no information is available,
-@var{length} will be 0, and @var{name} will be an empty string. This
+specified active attribute variable. If no information is available,
+@var{length} will be 0, and @var{name} will be an empty string. This
situation could occur if this function is called after a link operation
-that failed. If an error occurs, the return values @var{length},
+that failed. If an error occurs, the return values @var{length},
@var{size}, @var{type}, and @var{name} will be unmodified.
@code{GL_INVALID_VALUE} is generated if @var{program} is not a value
@end table
@code{glGetActiveUniform} returns information about an active uniform
-variable in the program object specified by @var{program}. The number of
-active uniform variables can be obtained by calling @code{glGetProgram}
-with the value @code{GL_ACTIVE_UNIFORMS}. A value of 0 for @var{index}
-selects the first active uniform variable. Permissible values for
-@var{index} range from 0 to the number of active uniform variables minus
-1.
+variable in the program object specified by @var{program}. The number
+of active uniform variables can be obtained by calling
+@code{glGetProgram} with the value @code{GL_ACTIVE_UNIFORMS}. A value
+of 0 for @var{index} selects the first active uniform variable.
+Permissible values for @var{index} range from 0 to the number of active
+uniform variables minus 1.
Shaders may use either built-in uniform variables, user-defined uniform
-variables, or both. Built-in uniform variables have a prefix of "gl_"
+variables, or both. Built-in uniform variables have a prefix of "gl_"
and reference existing OpenGL state or values derived from such state
(e.g., @var{gl_Fog}, @var{gl_ModelViewMatrix}, etc., see the OpenGL
Shading Language specification for a complete list.) User-defined
uniform variables have arbitrary names and obtain their values from the
-application through calls to @code{glUniform}. A uniform variable
+application through calls to @code{glUniform}. A uniform variable
(either built-in or user-defined) is considered active if it is
determined during the link operation that it may be accessed during
-program execution. Therefore, @var{program} should have previously been
+program execution. Therefore, @var{program} should have previously been
the target of a call to @code{glLinkProgram}, but it is not necessary
for it to have been linked successfully.
variable name in @var{program} can be obtained by calling
@code{glGetProgram} with the value @code{GL_ACTIVE_UNIFORM_MAX_LENGTH}.
This value should be used to allocate a buffer of sufficient size to
-store the returned uniform variable name. The size of this character
+store the returned uniform variable name. The size of this character
buffer is passed in @var{bufSize}, and a pointer to this character
buffer is passed in @var{name.}
@code{glGetActiveUniform} returns the name of the uniform variable
indicated by @var{index}, storing it in the character buffer specified
-by @var{name}. The string returned will be null terminated. The actual
+by @var{name}. The string returned will be null terminated. The actual
number of characters written into this buffer is returned in
@var{length}, and this count does not include the null termination
-character. If the length of the returned string is not required, a value
-of @code{NULL} can be passed in the @var{length} argument.
+character. If the length of the returned string is not required, a
+value of @code{NULL} can be passed in the @var{length} argument.
The @var{type} argument will return a pointer to the uniform variable's
-data type. The symbolic constants @code{GL_FLOAT}, @code{GL_FLOAT_VEC2},
-@code{GL_FLOAT_VEC3}, @code{GL_FLOAT_VEC4}, @code{GL_INT},
-@code{GL_INT_VEC2}, @code{GL_INT_VEC3}, @code{GL_INT_VEC4},
-@code{GL_BOOL}, @code{GL_BOOL_VEC2}, @code{GL_BOOL_VEC3},
-@code{GL_BOOL_VEC4}, @code{GL_FLOAT_MAT2}, @code{GL_FLOAT_MAT3},
-@code{GL_FLOAT_MAT4}, @code{GL_FLOAT_MAT2x3}, @code{GL_FLOAT_MAT2x4},
-@code{GL_FLOAT_MAT3x2}, @code{GL_FLOAT_MAT3x4}, @code{GL_FLOAT_MAT4x2},
-@code{GL_FLOAT_MAT4x3}, @code{GL_SAMPLER_1D}, @code{GL_SAMPLER_2D},
-@code{GL_SAMPLER_3D}, @code{GL_SAMPLER_CUBE},
+data type. The symbolic constants @code{GL_FLOAT},
+@code{GL_FLOAT_VEC2}, @code{GL_FLOAT_VEC3}, @code{GL_FLOAT_VEC4},
+@code{GL_INT}, @code{GL_INT_VEC2}, @code{GL_INT_VEC3},
+@code{GL_INT_VEC4}, @code{GL_BOOL}, @code{GL_BOOL_VEC2},
+@code{GL_BOOL_VEC3}, @code{GL_BOOL_VEC4}, @code{GL_FLOAT_MAT2},
+@code{GL_FLOAT_MAT3}, @code{GL_FLOAT_MAT4}, @code{GL_FLOAT_MAT2x3},
+@code{GL_FLOAT_MAT2x4}, @code{GL_FLOAT_MAT3x2}, @code{GL_FLOAT_MAT3x4},
+@code{GL_FLOAT_MAT4x2}, @code{GL_FLOAT_MAT4x3}, @code{GL_SAMPLER_1D},
+@code{GL_SAMPLER_2D}, @code{GL_SAMPLER_3D}, @code{GL_SAMPLER_CUBE},
@code{GL_SAMPLER_1D_SHADOW}, or @code{GL_SAMPLER_2D_SHADOW} may be
returned.
If one or more elements of an array are active, the name of the array is
returned in @var{name}, the type is returned in @var{type}, and the
@var{size} parameter returns the highest array element index used, plus
-one, as determined by the compiler and/or linker. Only one active
+one, as determined by the compiler and/or linker. Only one active
uniform variable will be reported for a uniform array.
Uniform variables that are declared as structures or arrays of
-structures will not be returned directly by this function. Instead, each
-of these uniform variables will be reduced to its fundamental components
-containing the "." and "[]" operators such that each of the names is
-valid as an argument to @code{glGetUniformLocation}. Each of these
-reduced uniform variables is counted as one active uniform variable and
-is assigned an index. A valid name cannot be a structure, an array of
-structures, or a subcomponent of a vector or matrix.
-
-The size of the uniform variable will be returned in @var{size}. Uniform
-variables other than arrays will have a size of 1. Structures and arrays
-of structures will be reduced as described earlier, such that each of
-the names returned will be a data type in the earlier list. If this
-reduction results in an array, the size returned will be as described
-for uniform arrays; otherwise, the size returned will be 1.
+structures will not be returned directly by this function. Instead,
+each of these uniform variables will be reduced to its fundamental
+components containing the "." and "[]" operators such that each of the
+names is valid as an argument to @code{glGetUniformLocation}. Each of
+these reduced uniform variables is counted as one active uniform
+variable and is assigned an index. A valid name cannot be a structure,
+an array of structures, or a subcomponent of a vector or matrix.
+
+The size of the uniform variable will be returned in @var{size}. Uniform
+variables other than arrays will have a size of 1. Structures and
+arrays of structures will be reduced as described earlier, such that
+each of the names returned will be a data type in the earlier list. If
+this reduction results in an array, the size returned will be as
+described for uniform arrays; otherwise, the size returned will be 1.
The list of active uniform variables may include both built-in uniform
variables (which begin with the prefix "gl_") as well as user-defined
uniform variable names.
This function will return as much information as it can about the
-specified active uniform variable. If no information is available,
-@var{length} will be 0, and @var{name} will be an empty string. This
+specified active uniform variable. If no information is available,
+@var{length} will be 0, and @var{name} will be an empty string. This
situation could occur if this function is called after a link operation
-that failed. If an error occurs, the return values @var{length},
+that failed. If an error occurs, the return values @var{length},
@var{size}, @var{type}, and @var{name} will be unmodified.
@code{GL_INVALID_VALUE} is generated if @var{program} is not a value
@end table
@code{glGetAttachedShaders} returns the names of the shader objects
-attached to @var{program}. The names of shader objects that are attached
-to @var{program} will be returned in @var{shaders.} The actual number of
-shader names written into @var{shaders} is returned in @var{count.} If
-no shader objects are attached to @var{program}, @var{count} is set to
-0. The maximum number of shader names that may be returned in
-@var{shaders} is specified by @var{maxCount}.
+attached to @var{program}. The names of shader objects that are
+attached to @var{program} will be returned in @var{shaders.} The actual
+number of shader names written into @var{shaders} is returned in
+@var{count.} If no shader objects are attached to @var{program},
+@var{count} is set to 0. The maximum number of shader names that may be
+returned in @var{shaders} is specified by @var{maxCount}.
If the number of names actually returned is not required (for instance,
if it has just been obtained by calling @code{glGetProgram}), a value of
-@code{NULL} may be passed for count. If no shader objects are attached
-to @var{program}, a value of 0 will be returned in @var{count}. The
+@code{NULL} may be passed for count. If no shader objects are attached
+to @var{program}, a value of 0 will be returned in @var{count}. The
actual number of attached shaders can be obtained by calling
@code{glGetProgram} with the value @code{GL_ATTACHED_SHADERS}.
@code{glGetAttribLocation} queries the previously linked program object
specified by @var{program} for the attribute variable specified by
@var{name} and returns the index of the generic vertex attribute that is
-bound to that attribute variable. If @var{name} is a matrix attribute
-variable, the index of the first column of the matrix is returned. If
+bound to that attribute variable. If @var{name} is a matrix attribute
+variable, the index of the first column of the matrix is returned. If
the named attribute variable is not an active attribute in the specified
program object or if @var{name} starts with the reserved prefix "gl_", a
value of -1 is returned.
The association between an attribute variable name and a generic
attribute index can be specified at any time by calling
-@code{glBindAttribLocation}. Attribute bindings do not go into effect
-until @code{glLinkProgram} is called. After a program object has been
+@code{glBindAttribLocation}. Attribute bindings do not go into effect
+until @code{glLinkProgram} is called. After a program object has been
linked successfully, the index values for attribute variables remain
-fixed until the next link command occurs. The attribute values can only
+fixed until the next link command occurs. The attribute values can only
be queried after a link if the link was successful.
@code{glGetAttribLocation} returns the binding that actually went into
effect the last time @code{glLinkProgram} was called for the specified
-program object. Attribute bindings that have been specified since the
+program object. Attribute bindings that have been specified since the
last link operation are not returned by @code{glGetAttribLocation}.
@code{GL_INVALID_OPERATION} is generated if @var{program} is not a value
@table @asis
@item @var{target}
-Specifies the target buffer object. The symbolic constant must be
+Specifies the target buffer object. The symbolic constant must be
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@item @var{value}
-Specifies the symbolic name of a buffer object parameter. Accepted
+Specifies the symbolic name of a buffer object parameter. Accepted
values are @code{GL_BUFFER_ACCESS}, @code{GL_BUFFER_MAPPED},
@code{GL_BUFFER_SIZE}, or @code{GL_BUFFER_USAGE}.
@table @asis
@item @code{GL_BUFFER_ACCESS}
@var{params} returns the access policy set while mapping the buffer
-object. The initial value is @code{GL_READ_WRITE}.
+object. The initial value is @code{GL_READ_WRITE}.
@item @code{GL_BUFFER_MAPPED}
@var{params} returns a flag indicating whether the buffer object is
-currently mapped. The initial value is @code{GL_FALSE}.
+currently mapped. The initial value is @code{GL_FALSE}.
@item @code{GL_BUFFER_SIZE}
@var{params} returns the size of the buffer object, measured in bytes.
The initial value is 0.
@item @code{GL_BUFFER_USAGE}
-@var{params} returns the buffer object's usage pattern. The initial
+@var{params} returns the buffer object's usage pattern. The initial
value is @code{GL_STATIC_DRAW}.
@end table
@table @asis
@item @var{target}
-Specifies the target buffer object. The symbolic constant must be
+Specifies the target buffer object. The symbolic constant must be
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@item @var{pname}
-Specifies the pointer to be returned. The symbolic constant must be
+Specifies the pointer to be returned. The symbolic constant must be
@code{GL_BUFFER_MAP_POINTER}.
@item @var{params}
@end table
-@code{glGetBufferPointerv} returns pointer information. @var{pname} is a
-symbolic constant indicating the pointer to be returned, which must be
+@code{glGetBufferPointerv} returns pointer information. @var{pname} is
+a symbolic constant indicating the pointer to be returned, which must be
@code{GL_BUFFER_MAP_POINTER}, the pointer to which the buffer object's
-data store is mapped. If the data store is not currently mapped,
-@code{NULL} is returned. @var{params} is a pointer to a location in
+data store is mapped. If the data store is not currently mapped,
+@code{NULL} is returned. @var{params} is a pointer to a location in
which to place the returned pointer value.
@code{GL_INVALID_ENUM} is generated if @var{target} or @var{pname} is
@table @asis
@item @var{target}
-Specifies the target buffer object. The symbolic constant must be
+Specifies the target buffer object. The symbolic constant must be
@code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@end table
@code{glGetBufferSubData} returns some or all of the data from the
-buffer object currently bound to @var{target}. Data starting at byte
+buffer object currently bound to @var{target}. Data starting at byte
offset @var{offset} and extending for @var{size} bytes is copied from
-the data store to the memory pointed to by @var{data}. An error is
+the data store to the memory pointed to by @var{data}. An error is
thrown if the buffer object is currently mapped, or if @var{offset} and
@var{size} together define a range beyond the bounds of the buffer
object's data store.
@table @asis
@item @var{plane}
-Specifies a clipping plane. The number of clipping planes depends on the
-implementation, but at least six clipping planes are supported. They are
-identified by symbolic names of the form @code{GL_CLIP_PLANE}@r{@var{i}}
-where i ranges from 0 to the value of @code{GL_MAX_CLIP_PLANES} - 1.
+Specifies a clipping plane. The number of clipping planes depends on
+the implementation, but at least six clipping planes are supported. They
+are identified by symbolic names of the form
+@code{GL_CLIP_PLANE}@r{@var{i}} where i ranges from 0 to the value of
+@code{GL_MAX_CLIP_PLANES} - 1.
@item @var{equation}
Returns four double-precision values that are the coefficients of the
-plane equation of @var{plane} in eye coordinates. The initial value is
+plane equation of @var{plane} in eye coordinates. The initial value is
(0, 0, 0, 0).
@end table
@table @asis
@item @var{target}
-The target color table. Must be @code{GL_COLOR_TABLE},
+The target color table. Must be @code{GL_COLOR_TABLE},
@code{GL_POST_CONVOLUTION_COLOR_TABLE},
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE}, @code{GL_PROXY_COLOR_TABLE},
@code{GL_PROXY_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_PROXY_POST_COLOR_MATRIX_COLOR_TABLE}.
@item @var{pname}
-The symbolic name of a color lookup table parameter. Must be one of
+The symbolic name of a color lookup table parameter. Must be one of
@code{GL_COLOR_TABLE_BIAS}, @code{GL_COLOR_TABLE_SCALE},
@code{GL_COLOR_TABLE_FORMAT}, @code{GL_COLOR_TABLE_WIDTH},
@code{GL_COLOR_TABLE_RED_SIZE}, @code{GL_COLOR_TABLE_GREEN_SIZE},
When @var{pname} is set to @code{GL_COLOR_TABLE_SCALE} or
@code{GL_COLOR_TABLE_BIAS}, @code{glGetColorTableParameter} returns the
color table scale or bias parameters for the table specified by
-@var{target}. For these queries, @var{target} must be set to
+@var{target}. For these queries, @var{target} must be set to
@code{GL_COLOR_TABLE}, @code{GL_POST_CONVOLUTION_COLOR_TABLE}, or
@code{GL_POST_COLOR_MATRIX_COLOR_TABLE} and @var{params} points to an
array of four elements, which receive the scale or bias factors for red,
green, blue, and alpha, in that order.
@code{glGetColorTableParameter} can also be used to retrieve the format
-and size parameters for a color table. For these queries, set
+and size parameters for a color table. For these queries, set
@var{target} to either the color table target or the proxy color table
-target. The format and size parameters are set by @code{glColorTable}.
+target. The format and size parameters are set by @code{glColorTable}.
The following table lists the format and size parameters that may be
-queried. For each symbolic constant listed below for @var{pname},
+queried. For each symbolic constant listed below for @var{pname},
@var{params} must point to an array of the given length and receive the
values indicated.
or @code{GL_POST_COLOR_MATRIX_COLOR_TABLE}.
@item @var{format}
-The format of the pixel data in @var{table}. The possible values are
+The format of the pixel data in @var{table}. The possible values are
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB},
@code{GL_BGR}, @code{GL_RGBA}, and @code{GL_BGRA}.
@item @var{type}
-The type of the pixel data in @var{table}. Symbolic constants
+The type of the pixel data in @var{table}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@end table
@code{glGetColorTable} returns in @var{table} the contents of the color
-table specified by @var{target}. No pixel transfer operations are
+table specified by @var{target}. No pixel transfer operations are
performed, but pixel storage modes that are applicable to
@code{glReadPixels} are performed.
Color components that are requested in the specified @var{format}, but
which are not included in the internal format of the color lookup table,
-are returned as zero. The assignments of internal color components to
+are returned as zero. The assignments of internal color components to
the components requested by @var{format} are
@table @asis
@table @asis
@item @var{target}
-Specifies which texture is to be obtained. @code{GL_TEXTURE_1D},
+Specifies which texture is to be obtained. @code{GL_TEXTURE_1D},
@code{GL_TEXTURE_2D}, and
@code{GL_TEXTURE_3D}@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z} are accepted.
@item @var{lod}
-Specifies the level-of-detail number of the desired image. Level 0 is
-the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
+Specifies the level-of-detail number of the desired image. Level 0 is
+the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
reduction image.
@item @var{img}
@end table
@code{glGetCompressedTexImage} returns the compressed texture image
-associated with @var{target} and @var{lod} into @var{img}. @var{img}
+associated with @var{target} and @var{lod} into @var{img}. @var{img}
should be an array of @code{GL_TEXTURE_COMPRESSED_IMAGE_SIZE} bytes.
@var{target} specifies whether the desired texture image was one
specified by @code{glTexImage1D} (@code{GL_TEXTURE_1D}),
@code{glTexImage2D} (@code{GL_TEXTURE_2D} or any of
@code{GL_TEXTURE_CUBE_MAP_*}), or @code{glTexImage3D}
-(@code{GL_TEXTURE_3D}). @var{lod} specifies the level-of-detail number
+(@code{GL_TEXTURE_3D}). @var{lod} specifies the level-of-detail number
of the desired image.
If a non-zero named buffer object is bound to the
To minimize errors, first verify that the texture is compressed by
calling @code{glGetTexLevelParameter} with argument
-@code{GL_TEXTURE_COMPRESSED}. If the texture is compressed, then
+@code{GL_TEXTURE_COMPRESSED}. If the texture is compressed, then
determine the amount of memory required to store the compressed texture
by calling @code{glGetTexLevelParameter} with argument
-@code{GL_TEXTURE_COMPRESSED_IMAGE_SIZE}. Finally, retrieve the internal
+@code{GL_TEXTURE_COMPRESSED_IMAGE_SIZE}. Finally, retrieve the internal
format of the texture by calling @code{glGetTexLevelParameter} with
-argument @code{GL_TEXTURE_INTERNAL_FORMAT}. To store the texture for
+argument @code{GL_TEXTURE_INTERNAL_FORMAT}. To store the texture for
later use, associate the internal format and size with the retrieved
-texture image. These data can be used by the respective texture or
+texture image. These data can be used by the respective texture or
subtexture loading routine used for loading @var{target} textures.
@code{GL_INVALID_VALUE} is generated if @var{lod} is less than zero or
@table @asis
@item @var{target}
-The filter to be retrieved. Must be one of @code{GL_CONVOLUTION_1D} or
+The filter to be retrieved. Must be one of @code{GL_CONVOLUTION_1D} or
@code{GL_CONVOLUTION_2D}.
@item @var{format}
-Format of the output image. Must be one of @code{GL_RED},
+Format of the output image. Must be one of @code{GL_RED},
@code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB},
@code{GL_BGR}, @code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, or
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Data type of components in the output image. Symbolic constants
+Data type of components in the output image. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@end table
@code{glGetConvolutionFilter} returns the current 1D or 2D convolution
-filter kernel as an image. The one- or two-dimensional image is placed
+filter kernel as an image. The one- or two-dimensional image is placed
in @var{image} according to the specifications in @var{format} and
-@var{type}. No pixel transfer operations are performed on this image,
+@var{type}. No pixel transfer operations are performed on this image,
but the relevant pixel storage modes are applied.
If a non-zero named buffer object is bound to the
into the buffer object's data store.
Color components that are present in @var{format} but not included in
-the internal format of the filter are returned as zero. The assignments
+the internal format of the filter are returned as zero. The assignments
of internal color components to the components of @var{format} are as
follows.
@table @asis
@item @var{target}
-The filter whose parameters are to be retrieved. Must be one of
+The filter whose parameters are to be retrieved. Must be one of
@code{GL_CONVOLUTION_1D}, @code{GL_CONVOLUTION_2D}, or
@code{GL_SEPARABLE_2D}.
@item @var{pname}
-The parameter to be retrieved. Must be one of
+The parameter to be retrieved. Must be one of
@code{GL_CONVOLUTION_BORDER_MODE}, @code{GL_CONVOLUTION_BORDER_COLOR},
@code{GL_CONVOLUTION_FILTER_SCALE}, @code{GL_CONVOLUTION_FILTER_BIAS},
@code{GL_CONVOLUTION_FORMAT}, @code{GL_CONVOLUTION_WIDTH},
@end table
@code{glGetConvolutionParameter} retrieves convolution parameters.
-@var{target} determines which convolution filter is queried. @var{pname}
+@var{target} determines which convolution filter is queried. @var{pname}
determines which parameter is returned:
@table @asis
@item @code{GL_CONVOLUTION_BORDER_MODE}
-The convolution border mode. See @code{glConvolutionParameter} for a
+The convolution border mode. See @code{glConvolutionParameter} for a
list of border modes.
@item @code{GL_CONVOLUTION_BORDER_COLOR}
-The current convolution border color. @var{params} must be a pointer to
+The current convolution border color. @var{params} must be a pointer to
an array of four elements, which will receive the red, green, blue, and
alpha border colors.
@item @code{GL_CONVOLUTION_FILTER_SCALE}
-The current filter scale factors. @var{params} must be a pointer to an
+The current filter scale factors. @var{params} must be a pointer to an
array of four elements, which will receive the red, green, blue, and
alpha filter scale factors in that order.
@item @code{GL_CONVOLUTION_FILTER_BIAS}
-The current filter bias factors. @var{params} must be a pointer to an
+The current filter bias factors. @var{params} must be a pointer to an
array of four elements, which will receive the red, green, blue, and
alpha filter bias terms in that order.
@item @code{GL_CONVOLUTION_FORMAT}
-The current internal format. See @code{glConvolutionFilter1D},
+The current internal format. See @code{glConvolutionFilter1D},
@code{glConvolutionFilter2D}, and @code{glSeparableFilter2D} for lists
of allowable formats.
@deftypefun GLenum glGetError
Return error information.
-@code{glGetError} returns the value of the error flag. Each detectable
-error is assigned a numeric code and symbolic name. When an error
-occurs, the error flag is set to the appropriate error code value. No
+@code{glGetError} returns the value of the error flag. Each detectable
+error is assigned a numeric code and symbolic name. When an error
+occurs, the error flag is set to the appropriate error code value. No
other errors are recorded until @code{glGetError} is called, the error
-code is returned, and the flag is reset to @code{GL_NO_ERROR}. If a call
-to @code{glGetError} returns @code{GL_NO_ERROR}, there has been no
+code is returned, and the flag is reset to @code{GL_NO_ERROR}. If a
+call to @code{glGetError} returns @code{GL_NO_ERROR}, there has been no
detectable error since the last call to @code{glGetError}, or since the
GL was initialized.
To allow for distributed implementations, there may be several error
-flags. If any single error flag has recorded an error, the value of that
-flag is returned and that flag is reset to @code{GL_NO_ERROR} when
-@code{glGetError} is called. If more than one flag has recorded an
+flags. If any single error flag has recorded an error, the value of
+that flag is returned and that flag is reset to @code{GL_NO_ERROR} when
+@code{glGetError} is called. If more than one flag has recorded an
error, @code{glGetError} returns and clears an arbitrary error flag
-value. Thus, @code{glGetError} should always be called in a loop, until
+value. Thus, @code{glGetError} should always be called in a loop, until
it returns @code{GL_NO_ERROR}, if all error flags are to be reset.
Initially, all error flags are set to @code{GL_NO_ERROR}.
@table @asis
@item @code{GL_NO_ERROR}
-No error has been recorded. The value of this symbolic constant is
+No error has been recorded. The value of this symbolic constant is
guaranteed to be 0.
@item @code{GL_INVALID_ENUM}
-An unacceptable value is specified for an enumerated argument. The
+An unacceptable value is specified for an enumerated argument. The
offending command is ignored and has no other side effect than to set
the error flag.
@item @code{GL_INVALID_VALUE}
-A numeric argument is out of range. The offending command is ignored and
-has no other side effect than to set the error flag.
+A numeric argument is out of range. The offending command is ignored
+and has no other side effect than to set the error flag.
@item @code{GL_INVALID_OPERATION}
-The specified operation is not allowed in the current state. The
+The specified operation is not allowed in the current state. The
offending command is ignored and has no other side effect than to set
the error flag.
@item @code{GL_STACK_OVERFLOW}
-This command would cause a stack overflow. The offending command is
+This command would cause a stack overflow. The offending command is
ignored and has no other side effect than to set the error flag.
@item @code{GL_STACK_UNDERFLOW}
-This command would cause a stack underflow. The offending command is
+This command would cause a stack underflow. The offending command is
ignored and has no other side effect than to set the error flag.
@item @code{GL_OUT_OF_MEMORY}
-There is not enough memory left to execute the command. The state of the
-GL is undefined, except for the state of the error flags, after this
+There is not enough memory left to execute the command. The state of
+the GL is undefined, except for the state of the error flags, after this
error is recorded.
@item @code{GL_TABLE_TOO_LARGE}
The specified table exceeds the implementation's maximum supported table
-size. The offending command is ignored and has no other side effect than
-to set the error flag.
+size. The offending command is ignored and has no other side effect
+than to set the error flag.
@end table
When an error flag is set, results of a GL operation are undefined only
-if @code{GL_OUT_OF_MEMORY} has occurred. In all other cases, the command
-generating the error is ignored and has no effect on the GL state or
-frame buffer contents. If the generating command returns a value, it
-returns 0. If @code{glGetError} itself generates an error, it returns 0.
+if @code{GL_OUT_OF_MEMORY} has occurred. In all other cases, the
+command generating the error is ignored and has no effect on the GL
+state or frame buffer contents. If the generating command returns a
+value, it returns 0. If @code{glGetError} itself generates an error, it
+returns 0.
@code{GL_INVALID_OPERATION} is generated if @code{glGetError} is
executed between the execution of @code{glBegin} and the corresponding
-execution of @code{glEnd}. In this case, @code{glGetError} returns 0.
+execution of @code{glEnd}. In this case, @code{glGetError} returns 0.
@end deftypefun
Must be one of @code{GL_HISTOGRAM} or @code{GL_PROXY_HISTOGRAM}.
@item @var{pname}
-The name of the parameter to be retrieved. Must be one of
+The name of the parameter to be retrieved. Must be one of
@code{GL_HISTOGRAM_WIDTH}, @code{GL_HISTOGRAM_FORMAT},
@code{GL_HISTOGRAM_RED_SIZE}, @code{GL_HISTOGRAM_GREEN_SIZE},
@code{GL_HISTOGRAM_BLUE_SIZE}, @code{GL_HISTOGRAM_ALPHA_SIZE},
@end table
@code{glGetHistogramParameter} is used to query parameter values for the
-current histogram or for a proxy. The histogram state information may be
-queried by calling @code{glGetHistogramParameter} with a @var{target} of
-@code{GL_HISTOGRAM} (to obtain information for the current histogram
+current histogram or for a proxy. The histogram state information may
+be queried by calling @code{glGetHistogramParameter} with a @var{target}
+of @code{GL_HISTOGRAM} (to obtain information for the current histogram
table) or @code{GL_PROXY_HISTOGRAM} (to obtain information from the most
recent proxy request) and one of the following values for the
@var{pname} argument:
@item @var{reset}
If @code{GL_TRUE}, each component counter that is actually returned is
-reset to zero. (Other counters are unaffected.) If @code{GL_FALSE}, none
-of the counters in the histogram table is modified.
+reset to zero. (Other counters are unaffected.) If @code{GL_FALSE},
+none of the counters in the histogram table is modified.
@item @var{format}
-The format of values to be returned in @var{values}. Must be one of
+The format of values to be returned in @var{values}. Must be one of
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA}, @code{GL_BGRA},
@code{GL_LUMINANCE}, or @code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-The type of values to be returned in @var{values}. Symbolic constants
+The type of values to be returned in @var{values}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@end table
@code{glGetHistogram} returns the current histogram table as a
-one-dimensional image with the same width as the histogram. No pixel
+one-dimensional image with the same width as the histogram. No pixel
transfer operations are performed on this image, but pixel storage modes
that are applicable to 1D images are honored.
Color components that are requested in the specified @var{format}, but
which are not included in the internal format of the histogram, are
-returned as zero. The assignments of internal color components to the
+returned as zero. The assignments of internal color components to the
components requested by @var{format} are:
@table @asis
@table @asis
@item @var{light}
-Specifies a light source. The number of possible lights depends on the
-implementation, but at least eight lights are supported. They are
+Specifies a light source. The number of possible lights depends on the
+implementation, but at least eight lights are supported. They are
identified by symbolic names of the form @code{GL_LIGHT}@r{@var{i}}
where @r{@var{i}} ranges from 0 to the value of @code{GL_MAX_LIGHTS} -
1.
@item @var{pname}
-Specifies a light source parameter for @var{light}. Accepted symbolic
+Specifies a light source parameter for @var{light}. Accepted symbolic
names are @code{GL_AMBIENT}, @code{GL_DIFFUSE}, @code{GL_SPECULAR},
@code{GL_POSITION}, @code{GL_SPOT_DIRECTION}, @code{GL_SPOT_EXPONENT},
@code{GL_SPOT_CUTOFF}, @code{GL_CONSTANT_ATTENUATION},
@end table
@code{glGetLight} returns in @var{params} the value or values of a light
-source parameter. @var{light} names the light and is a symbolic name of
+source parameter. @var{light} names the light and is a symbolic name of
the form @code{GL_LIGHT}@r{@var{i}} where i ranges from 0 to the value
-of @code{GL_MAX_LIGHTS} - 1. @code{GL_MAX_LIGHTS} is an implementation
-dependent constant that is greater than or equal to eight. @var{pname}
+of @code{GL_MAX_LIGHTS} - 1. @code{GL_MAX_LIGHTS} is an implementation
+dependent constant that is greater than or equal to eight. @var{pname}
specifies one of ten light source parameters, again by symbolic name.
The following parameters are defined:
@table @asis
@item @code{GL_AMBIENT}
@var{params} returns four integer or floating-point values representing
-the ambient intensity of the light source. Integer values, when
+the ambient intensity of the light source. Integer values, when
requested, are linearly mapped from the internal floating-point
representation such that 1.0 maps to the most positive representable
integer value, and @r{-1.0} maps to the most negative representable
-integer value. If the internal value is outside the range @r{[-1,1]},
-the corresponding integer return value is undefined. The initial value
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
is (0, 0, 0, 1).
@item @code{GL_DIFFUSE}
@var{params} returns four integer or floating-point values representing
-the diffuse intensity of the light source. Integer values, when
+the diffuse intensity of the light source. Integer values, when
requested, are linearly mapped from the internal floating-point
representation such that 1.0 maps to the most positive representable
integer value, and @r{-1.0} maps to the most negative representable
-integer value. If the internal value is outside the range @r{[-1,1]},
-the corresponding integer return value is undefined. The initial value
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
for @code{GL_LIGHT0} is (1, 1, 1, 1); for other lights, the initial
value is (0, 0, 0, 0).
@item @code{GL_SPECULAR}
@var{params} returns four integer or floating-point values representing
-the specular intensity of the light source. Integer values, when
+the specular intensity of the light source. Integer values, when
requested, are linearly mapped from the internal floating-point
representation such that 1.0 maps to the most positive representable
integer value, and @r{-1.0} maps to the most negative representable
-integer value. If the internal value is outside the range @r{[-1,1]},
-the corresponding integer return value is undefined. The initial value
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
for @code{GL_LIGHT0} is (1, 1, 1, 1); for other lights, the initial
value is (0, 0, 0, 0).
@item @code{GL_POSITION}
@var{params} returns four integer or floating-point values representing
-the position of the light source. Integer values, when requested, are
+the position of the light source. Integer values, when requested, are
computed by rounding the internal floating-point values to the nearest
-integer value. The returned values are those maintained in eye
-coordinates. They will not be equal to the values specified using
+integer value. The returned values are those maintained in eye
+coordinates. They will not be equal to the values specified using
@code{glLight}, unless the modelview matrix was identity at the time
-@code{glLight} was called. The initial value is (0, 0, 1, 0).
+@code{glLight} was called. The initial value is (0, 0, 1, 0).
@item @code{GL_SPOT_DIRECTION}
@var{params} returns three integer or floating-point values representing
-the direction of the light source. Integer values, when requested, are
+the direction of the light source. Integer values, when requested, are
computed by rounding the internal floating-point values to the nearest
-integer value. The returned values are those maintained in eye
-coordinates. They will not be equal to the values specified using
+integer value. The returned values are those maintained in eye
+coordinates. They will not be equal to the values specified using
@code{glLight}, unless the modelview matrix was identity at the time
-@code{glLight} was called. Although spot direction is normalized before
+@code{glLight} was called. Although spot direction is normalized before
being used in the lighting equation, the returned values are the
-transformed versions of the specified values prior to normalization. The
+transformed versions of the specified values prior to normalization. The
initial value is @r{(0,0-1)}.
@item @code{GL_SPOT_EXPONENT}
@var{params} returns a single integer or floating-point value
-representing the spot exponent of the light. An integer value, when
+representing the spot exponent of the light. An integer value, when
requested, is computed by rounding the internal floating-point
-representation to the nearest integer. The initial value is 0.
+representation to the nearest integer. The initial value is 0.
@item @code{GL_SPOT_CUTOFF}
@var{params} returns a single integer or floating-point value
-representing the spot cutoff angle of the light. An integer value, when
+representing the spot cutoff angle of the light. An integer value, when
requested, is computed by rounding the internal floating-point
-representation to the nearest integer. The initial value is 180.
+representation to the nearest integer. The initial value is 180.
@item @code{GL_CONSTANT_ATTENUATION}
@var{params} returns a single integer or floating-point value
representing the constant (not distance-related) attenuation of the
-light. An integer value, when requested, is computed by rounding the
-internal floating-point representation to the nearest integer. The
+light. An integer value, when requested, is computed by rounding the
+internal floating-point representation to the nearest integer. The
initial value is 1.
@item @code{GL_LINEAR_ATTENUATION}
@var{params} returns a single integer or floating-point value
-representing the linear attenuation of the light. An integer value, when
-requested, is computed by rounding the internal floating-point
-representation to the nearest integer. The initial value is 0.
+representing the linear attenuation of the light. An integer value,
+when requested, is computed by rounding the internal floating-point
+representation to the nearest integer. The initial value is 0.
@item @code{GL_QUADRATIC_ATTENUATION}
@var{params} returns a single integer or floating-point value
-representing the quadratic attenuation of the light. An integer value,
+representing the quadratic attenuation of the light. An integer value,
when requested, is computed by rounding the internal floating-point
-representation to the nearest integer. The initial value is 0.
+representation to the nearest integer. The initial value is 0.
@end table
@table @asis
@item @var{target}
-Specifies the symbolic name of a map. Accepted values are
+Specifies the symbolic name of a map. Accepted values are
@code{GL_MAP1_COLOR_4}, @code{GL_MAP1_INDEX}, @code{GL_MAP1_NORMAL},
@code{GL_MAP1_TEXTURE_COORD_1}, @code{GL_MAP1_TEXTURE_COORD_2},
@code{GL_MAP1_TEXTURE_COORD_3}, @code{GL_MAP1_TEXTURE_COORD_4},
@code{GL_MAP2_VERTEX_3}, and @code{GL_MAP2_VERTEX_4}.
@item @var{query}
-Specifies which parameter to return. Symbolic names @code{GL_COEFF},
+Specifies which parameter to return. Symbolic names @code{GL_COEFF},
@code{GL_ORDER}, and @code{GL_DOMAIN} are accepted.
@item @var{v}
@end table
-@code{glMap1} and @code{glMap2} define evaluators. @code{glGetMap}
-returns evaluator parameters. @var{target} chooses a map, @var{query}
+@code{glMap1} and @code{glMap2} define evaluators. @code{glGetMap}
+returns evaluator parameters. @var{target} chooses a map, @var{query}
selects a specific parameter, and @var{v} points to storage where the
values will be returned.
@var{v} returns the control points for the evaluator function.
One-dimensional evaluators return @r{@var{order}} control points, and
two-dimensional evaluators return @r{@var{uorder}×@var{vorder}} control
-points. Each control point consists of one, two, three, or four integer,
-single-precision floating-point, or double-precision floating-point
-values, depending on the type of the evaluator. The GL returns
-two-dimensional control points in row-major order, incrementing the
-@r{@var{uorder}} index quickly and the @r{@var{vorder}} index after each
-row. Integer values, when requested, are computed by rounding the
+points. Each control point consists of one, two, three, or four
+integer, single-precision floating-point, or double-precision
+floating-point values, depending on the type of the evaluator. The GL
+returns two-dimensional control points in row-major order, incrementing
+the @r{@var{uorder}} index quickly and the @r{@var{vorder}} index after
+each row. Integer values, when requested, are computed by rounding the
internal floating-point values to the nearest integer values.
@item @code{GL_ORDER}
-@var{v} returns the order of the evaluator function. One-dimensional
-evaluators return a single value, @r{@var{order}}. The initial value is
-1. Two-dimensional evaluators return two values, @r{@var{uorder}} and
-@r{@var{vorder}}. The initial value is 1,1.
+@var{v} returns the order of the evaluator function. One-dimensional
+evaluators return a single value, @r{@var{order}}. The initial value is
+1. Two-dimensional evaluators return two values, @r{@var{uorder}} and
+@r{@var{vorder}}. The initial value is 1,1.
@item @code{GL_DOMAIN}
@var{v} returns the linear @r{@var{u}} and @r{@var{v}} mapping
-parameters. One-dimensional evaluators return two values, @r{@var{u1}}
-and @r{@var{u2}}, as specified by @code{glMap1}. Two-dimensional
+parameters. One-dimensional evaluators return two values, @r{@var{u1}}
+and @r{@var{u2}}, as specified by @code{glMap1}. Two-dimensional
evaluators return four values (@r{@var{u1}}, @r{@var{u2}}, @r{@var{v1}},
-and @r{@var{v2}}) as specified by @code{glMap2}. Integer values, when
+and @r{@var{v2}}) as specified by @code{glMap2}. Integer values, when
requested, are computed by rounding the internal floating-point values
to the nearest integer values.
@table @asis
@item @var{face}
-Specifies which of the two materials is being queried. @code{GL_FRONT}
+Specifies which of the two materials is being queried. @code{GL_FRONT}
or @code{GL_BACK} are accepted, representing the front and back
materials, respectively.
@item @var{pname}
-Specifies the material parameter to return. @code{GL_AMBIENT},
+Specifies the material parameter to return. @code{GL_AMBIENT},
@code{GL_DIFFUSE}, @code{GL_SPECULAR}, @code{GL_EMISSION},
@code{GL_SHININESS}, and @code{GL_COLOR_INDEXES} are accepted.
@end table
@code{glGetMaterial} returns in @var{params} the value or values of
-parameter @var{pname} of material @var{face}. Six parameters are
+parameter @var{pname} of material @var{face}. Six parameters are
defined:
@table @asis
@item @code{GL_AMBIENT}
@var{params} returns four integer or floating-point values representing
-the ambient reflectance of the material. Integer values, when requested,
-are linearly mapped from the internal floating-point representation such
-that 1.0 maps to the most positive representable integer value, and
-@r{-1.0} maps to the most negative representable integer value. If the
-internal value is outside the range @r{[-1,1]}, the corresponding
-integer return value is undefined. The initial value is (0.2, 0.2, 0.2,
-1.0)
+the ambient reflectance of the material. Integer values, when
+requested, are linearly mapped from the internal floating-point
+representation such that 1.0 maps to the most positive representable
+integer value, and @r{-1.0} maps to the most negative representable
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
+is (0.2, 0.2, 0.2, 1.0)
@item @code{GL_DIFFUSE}
@var{params} returns four integer or floating-point values representing
-the diffuse reflectance of the material. Integer values, when requested,
-are linearly mapped from the internal floating-point representation such
-that 1.0 maps to the most positive representable integer value, and
-@r{-1.0} maps to the most negative representable integer value. If the
-internal value is outside the range @r{[-1,1]}, the corresponding
-integer return value is undefined. The initial value is (0.8, 0.8, 0.8,
-1.0).
+the diffuse reflectance of the material. Integer values, when
+requested, are linearly mapped from the internal floating-point
+representation such that 1.0 maps to the most positive representable
+integer value, and @r{-1.0} maps to the most negative representable
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
+is (0.8, 0.8, 0.8, 1.0).
@item @code{GL_SPECULAR}
@var{params} returns four integer or floating-point values representing
-the specular reflectance of the material. Integer values, when
+the specular reflectance of the material. Integer values, when
requested, are linearly mapped from the internal floating-point
representation such that 1.0 maps to the most positive representable
integer value, and @r{-1.0} maps to the most negative representable
-integer value. If the internal value is outside the range @r{[-1,1]},
-the corresponding integer return value is undefined. The initial value
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
is (0, 0, 0, 1).
@item @code{GL_EMISSION}
@var{params} returns four integer or floating-point values representing
-the emitted light intensity of the material. Integer values, when
+the emitted light intensity of the material. Integer values, when
requested, are linearly mapped from the internal floating-point
representation such that 1.0 maps to the most positive representable
integer value, and @r{-1.0} maps to the most negative representable
-integer value. If the internal value is outside the range @r{[-1,1]},
-the corresponding integer return value is undefined. The initial value
+integer value. If the internal value is outside the range @r{[-1,1]},
+the corresponding integer return value is undefined. The initial value
is (0, 0, 0, 1).
@item @code{GL_SHININESS}
@var{params} returns one integer or floating-point value representing
-the specular exponent of the material. Integer values, when requested,
+the specular exponent of the material. Integer values, when requested,
are computed by rounding the internal floating-point value to the
-nearest integer value. The initial value is 0.
+nearest integer value. The initial value is 0.
@item @code{GL_COLOR_INDEXES}
@var{params} returns three integer or floating-point values representing
-the ambient, diffuse, and specular indices of the material. These
-indices are used only for color index lighting. (All the other
+the ambient, diffuse, and specular indices of the material. These
+indices are used only for color index lighting. (All the other
parameters are used only for RGBA lighting.) Integer values, when
requested, are computed by rounding the internal floating-point values
to the nearest integer values.
Must be @code{GL_MINMAX}.
@item @var{pname}
-The parameter to be retrieved. Must be one of @code{GL_MINMAX_FORMAT} or
-@code{GL_MINMAX_SINK}.
+The parameter to be retrieved. Must be one of @code{GL_MINMAX_FORMAT}
+or @code{GL_MINMAX_SINK}.
@item @var{params}
A pointer to storage for the retrieved parameters.
@item @var{reset}
If @code{GL_TRUE}, all entries in the minmax table that are actually
-returned are reset to their initial values. (Other entries are
+returned are reset to their initial values. (Other entries are
unaltered.) If @code{GL_FALSE}, the minmax table is unaltered.
@item @var{format}
-The format of the data to be returned in @var{values}. Must be one of
+The format of the data to be returned in @var{values}. Must be one of
@code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA}, @code{GL_BGRA},
@code{GL_LUMINANCE}, or @code{GL_LUMINANCE_ALPHA}.
@item @var{types}
-The type of the data to be returned in @var{values}. Symbolic constants
+The type of the data to be returned in @var{values}. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@code{glGetMinmax} returns the accumulated minimum and maximum pixel
values (computed on a per-component basis) in a one-dimensional image of
-width 2. The first set of return values are the minima, and the second
-set of return values are the maxima. The format of the return values is
+width 2. The first set of return values are the minima, and the second
+set of return values are the maxima. The format of the return values is
determined by @var{format}, and their type is determined by @var{types}.
If a non-zero named buffer object is bound to the
No pixel transfer operations are performed on the return values, but
pixel storage modes that are applicable to one-dimensional images are
-performed. Color components that are requested in the specified
+performed. Color components that are requested in the specified
@var{format}, but that are not included in the internal format of the
-minmax table, are returned as zero. The assignment of internal color
+minmax table, are returned as zero. The assignment of internal color
components to the components requested by @var{format} are as follows:
@end table
If @var{reset} is @code{GL_TRUE}, the minmax table entries corresponding
-to the return values are reset to their initial values. Minimum and
+to the return values are reset to their initial values. Minimum and
maximum values that are not returned are not modified, even if
@var{reset} is @code{GL_TRUE}.
@table @asis
@item @var{map}
-Specifies the name of the pixel map to return. Accepted values are
+Specifies the name of the pixel map to return. Accepted values are
@code{GL_PIXEL_MAP_I_TO_I}, @code{GL_PIXEL_MAP_S_TO_S},
@code{GL_PIXEL_MAP_I_TO_R}, @code{GL_PIXEL_MAP_I_TO_G},
@code{GL_PIXEL_MAP_I_TO_B}, @code{GL_PIXEL_MAP_I_TO_A},
@end table
See the @code{glPixelMap} reference page for a description of the
-acceptable values for the @var{map} parameter. @code{glGetPixelMap}
+acceptable values for the @var{map} parameter. @code{glGetPixelMap}
returns in @var{data} the contents of the pixel map specified in
-@var{map}. Pixel maps are used during the execution of
+@var{map}. Pixel maps are used during the execution of
@code{glReadPixels}, @code{glDrawPixels}, @code{glCopyPixels},
@code{glTexImage1D}, @code{glTexImage2D}, @code{glTexImage3D},
@code{glTexSubImage1D}, @code{glTexSubImage2D}, @code{glTexSubImage3D},
@code{glCopyTexImage1D}, @code{glCopyTexImage2D},
@code{glCopyTexSubImage1D}, @code{glCopyTexSubImage2D}, and
-@code{glCopyTexSubImage3D}. to map color indices, stencil indices, color
-components, and depth components to other values.
+@code{glCopyTexSubImage3D}. to map color indices, stencil indices,
+color components, and depth components to other values.
If a non-zero named buffer object is bound to the
@code{GL_PIXEL_PACK_BUFFER} target (see @code{glBindBuffer}) while a
Unsigned integer values, if requested, are linearly mapped from the
internal fixed or floating-point representation such that 1.0 maps to
-the largest representable integer value, and 0.0 maps to 0. Return
+the largest representable integer value, and 0.0 maps to 0. Return
unsigned integer values are undefined if the map value was not in the
range [0,1].
@table @asis
@item @var{pname}
-Specifies the array or buffer pointer to be returned. Symbolic constants
-@code{GL_COLOR_ARRAY_POINTER}, @code{GL_EDGE_FLAG_ARRAY_POINTER},
-@code{GL_FOG_COORD_ARRAY_POINTER}, @code{GL_FEEDBACK_BUFFER_POINTER},
-@code{GL_INDEX_ARRAY_POINTER}, @code{GL_NORMAL_ARRAY_POINTER},
-@code{GL_SECONDARY_COLOR_ARRAY_POINTER},
+Specifies the array or buffer pointer to be returned. Symbolic
+constants @code{GL_COLOR_ARRAY_POINTER},
+@code{GL_EDGE_FLAG_ARRAY_POINTER}, @code{GL_FOG_COORD_ARRAY_POINTER},
+@code{GL_FEEDBACK_BUFFER_POINTER}, @code{GL_INDEX_ARRAY_POINTER},
+@code{GL_NORMAL_ARRAY_POINTER}, @code{GL_SECONDARY_COLOR_ARRAY_POINTER},
@code{GL_SELECTION_BUFFER_POINTER},
@code{GL_TEXTURE_COORD_ARRAY_POINTER}, or @code{GL_VERTEX_ARRAY_POINTER}
are accepted.
@end table
-@code{glGetPointerv} returns pointer information. @var{pname} is a
+@code{glGetPointerv} returns pointer information. @var{pname} is a
symbolic constant indicating the pointer to be returned, and
@var{params} is a pointer to a location in which to place the returned
data.
object was bound to the @code{GL_ARRAY_BUFFER} target (see
@code{glBindBuffer}) when the desired pointer was previously specified,
the pointer returned is a byte offset into the buffer object's data
-store. Buffer objects are only available in OpenGL versions 1.5 and
+store. Buffer objects are only available in OpenGL versions 1.5 and
greater.
@code{GL_INVALID_ENUM} is generated if @var{pname} is not an accepted
@table @asis
@item @var{pattern}
-Returns the stipple pattern. The initial value is all 1's.
+Returns the stipple pattern. The initial value is all 1's.
@end table
@code{glGetPolygonStipple} returns to @var{pattern} a @r{32×32} polygon
-stipple pattern. The pattern is packed into memory as if
+stipple pattern. The pattern is packed into memory as if
@code{glReadPixels} with both @var{height} and @var{width} of 32,
@var{type} of @code{GL_BITMAP}, and @var{format} of
@code{GL_COLOR_INDEX} were called, and the stipple pattern were stored
-in an internal @r{32×32} color index buffer. Unlike @code{glReadPixels},
-however, pixel transfer operations (shift, offset, pixel map) are not
-applied to the returned stipple image.
+in an internal @r{32×32} color index buffer. Unlike
+@code{glReadPixels}, however, pixel transfer operations (shift, offset,
+pixel map) are not applied to the returned stipple image.
If a non-zero named buffer object is bound to the
@code{GL_PIXEL_PACK_BUFFER} target (see @code{glBindBuffer}) while a
@end table
@code{glGetProgramInfoLog} returns the information log for the specified
-program object. The information log for a program object is modified
-when the program object is linked or validated. The string that is
+program object. The information log for a program object is modified
+when the program object is linked or validated. The string that is
returned will be null terminated.
@code{glGetProgramInfoLog} returns in @var{infoLog} as much of the
information log as it can, up to a maximum of @var{maxLength}
-characters. The number of characters actually returned, excluding the
-null termination character, is specified by @var{length}. If the length
+characters. The number of characters actually returned, excluding the
+null termination character, is specified by @var{length}. If the length
of the returned string is not required, a value of @code{NULL} can be
-passed in the @var{length} argument. The size of the buffer required to
+passed in the @var{length} argument. The size of the buffer required to
store the returned information log can be obtained by calling
@code{glGetProgram} with the value @code{GL_INFO_LOG_LENGTH}.
The information log for a program object is either an empty string, or a
string containing information about the last link operation, or a string
-containing information about the last validation operation. It may
+containing information about the last validation operation. It may
contain diagnostic messages, warning messages, and other information.
When a program object is created, its information log will be a string
of length 0.
Specifies the program object to be queried.
@item @var{pname}
-Specifies the object parameter. Accepted symbolic names are
+Specifies the object parameter. Accepted symbolic names are
@code{GL_DELETE_STATUS}, @code{GL_LINK_STATUS},
@code{GL_VALIDATE_STATUS}, @code{GL_INFO_LOG_LENGTH},
@code{GL_ATTACHED_SHADERS}, @code{GL_ACTIVE_ATTRIBUTES},
@end table
@code{glGetProgram} returns in @var{params} the value of a parameter for
-a specific program object. The following parameters are defined:
+a specific program object. The following parameters are defined:
@table @asis
@item @code{GL_DELETE_STATUS}
@var{params} returns the number of characters in the information log for
@var{program} including the null termination character (i.e., the size
-of the character buffer required to store the information log). If
+of the character buffer required to store the information log). If
@var{program} has no information log, a value of 0 is returned.
@item @code{GL_ATTACHED_SHADERS}
@var{params} returns the length of the longest active uniform variable
name for @var{program}, including the null termination character (i.e.,
the size of the character buffer required to store the longest uniform
-variable name). If no active uniform variables exist, 0 is returned.
+variable name). If no active uniform variables exist, 0 is returned.
@end table
@table @asis
@item @var{target}
-Specifies a query object target. Must be @code{GL_SAMPLES_PASSED}.
+Specifies a query object target. Must be @code{GL_SAMPLES_PASSED}.
@item @var{pname}
-Specifies the symbolic name of a query object target parameter. Accepted
+Specifies the symbolic name of a query object target parameter. Accepted
values are @code{GL_CURRENT_QUERY} or @code{GL_QUERY_COUNTER_BITS}.
@item @var{params}
@code{glGetQueryiv} returns in @var{params} a selected parameter of the
query object target specified by @var{target}.
-@var{pname} names a specific query object target parameter. When
+@var{pname} names a specific query object target parameter. When
@var{target} is @code{GL_SAMPLES_PASSED}, @var{pname} can be as follows:
@table @asis
@item @code{GL_CURRENT_QUERY}
@var{params} returns the name of the currently active occlusion query
-object. If no occlusion query is active, 0 is returned. The initial
+object. If no occlusion query is active, 0 is returned. The initial
value is 0.
@item @code{GL_QUERY_COUNTER_BITS}
@var{params} returns the number of bits in the query counter used to
-accumulate passing samples. If the number of bits returned is 0, the
+accumulate passing samples. If the number of bits returned is 0, the
implementation does not support a query counter, and the results
obtained from @code{glGetQueryObject} are useless.
Specifies the name of a query object.
@item @var{pname}
-Specifies the symbolic name of a query object parameter. Accepted values
-are @code{GL_QUERY_RESULT} or @code{GL_QUERY_RESULT_AVAILABLE}.
+Specifies the symbolic name of a query object parameter. Accepted
+values are @code{GL_QUERY_RESULT} or @code{GL_QUERY_RESULT_AVAILABLE}.
@item @var{params}
Returns the requested data.
@code{glGetQueryObject} returns in @var{params} a selected parameter of
the query object specified by @var{id}.
-@var{pname} names a specific query object parameter. @var{pname} can be
+@var{pname} names a specific query object parameter. @var{pname} can be
as follows:
@table @asis
@item @code{GL_QUERY_RESULT}
@var{params} returns the value of the query object's passed samples
-counter. The initial value is 0.
+counter. The initial value is 0.
@item @code{GL_QUERY_RESULT_AVAILABLE}
@var{params} returns whether the passed samples counter is immediately
-available. If a delay would occur waiting for the query result,
-@code{GL_FALSE} is returned. Otherwise, @code{GL_TRUE} is returned,
+available. If a delay would occur waiting for the query result,
+@code{GL_FALSE} is returned. Otherwise, @code{GL_TRUE} is returned,
which also indicates that the results of all previous queries are
available as well.
@table @asis
@item @var{target}
-The separable filter to be retrieved. Must be @code{GL_SEPARABLE_2D}.
+The separable filter to be retrieved. Must be @code{GL_SEPARABLE_2D}.
@item @var{format}
-Format of the output images. Must be one of @code{GL_RED},
+Format of the output images. Must be one of @code{GL_RED},
@code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB},
@code{GL_BGR}@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, or
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Data type of components in the output images. Symbolic constants
+Data type of components in the output images. Symbolic constants
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@end table
@code{glGetSeparableFilter} returns the two one-dimensional filter
-kernel images for the current separable 2D convolution filter. The row
+kernel images for the current separable 2D convolution filter. The row
image is placed in @var{row} and the column image is placed in
@var{column} according to the specifications in @var{format} and
-@var{type}. (In the current implementation, @var{span} is not affected
+@var{type}. (In the current implementation, @var{span} is not affected
in any way.) No pixel transfer operations are performed on the images,
but the relevant pixel storage modes are applied.
store.
Color components that are present in @var{format} but not included in
-the internal format of the filters are returned as zero. The assignments
-of internal color components to the components of @var{format} are as
-follows:
+the internal format of the filters are returned as zero. The
+assignments of internal color components to the components of
+@var{format} are as follows:
@end table
@code{glGetShaderInfoLog} returns the information log for the specified
-shader object. The information log for a shader object is modified when
-the shader is compiled. The string that is returned will be null
+shader object. The information log for a shader object is modified when
+the shader is compiled. The string that is returned will be null
terminated.
@code{glGetShaderInfoLog} returns in @var{infoLog} as much of the
information log as it can, up to a maximum of @var{maxLength}
-characters. The number of characters actually returned, excluding the
-null termination character, is specified by @var{length}. If the length
+characters. The number of characters actually returned, excluding the
+null termination character, is specified by @var{length}. If the length
of the returned string is not required, a value of @code{NULL} can be
-passed in the @var{length} argument. The size of the buffer required to
+passed in the @var{length} argument. The size of the buffer required to
store the returned information log can be obtained by calling
@code{glGetShader} with the value @code{GL_INFO_LOG_LENGTH}.
The information log for a shader object is a string that may contain
diagnostic messages, warning messages, and other information about the
-last compile operation. When a shader object is created, its information
-log will be a string of length 0.
+last compile operation. When a shader object is created, its
+information log will be a string of length 0.
@code{GL_INVALID_VALUE} is generated if @var{shader} is not a value
generated by OpenGL.
@end table
@code{glGetShaderSource} returns the concatenation of the source code
-strings from the shader object specified by @var{shader}. The source
+strings from the shader object specified by @var{shader}. The source
code strings for a shader object are the result of a previous call to
-@code{glShaderSource}. The string returned by the function will be null
+@code{glShaderSource}. The string returned by the function will be null
terminated.
@code{glGetShaderSource} returns in @var{source} as much of the source
-code string as it can, up to a maximum of @var{bufSize} characters. The
+code string as it can, up to a maximum of @var{bufSize} characters. The
number of characters actually returned, excluding the null termination
-character, is specified by @var{length}. If the length of the returned
+character, is specified by @var{length}. If the length of the returned
string is not required, a value of @code{NULL} can be passed in the
-@var{length} argument. The size of the buffer required to store the
+@var{length} argument. The size of the buffer required to store the
returned source code string can be obtained by calling
@code{glGetShader} with the value @code{GL_SHADER_SOURCE_LENGTH}.
Specifies the shader object to be queried.
@item @var{pname}
-Specifies the object parameter. Accepted symbolic names are
+Specifies the object parameter. Accepted symbolic names are
@code{GL_SHADER_TYPE}, @code{GL_DELETE_STATUS},
@code{GL_COMPILE_STATUS}, @code{GL_INFO_LOG_LENGTH},
@code{GL_SHADER_SOURCE_LENGTH}.
@end table
@code{glGetShader} returns in @var{params} the value of a parameter for
-a specific shader object. The following parameters are defined:
+a specific shader object. The following parameters are defined:
@table @asis
@item @code{GL_SHADER_TYPE}
@item @code{GL_INFO_LOG_LENGTH}
@var{params} returns the number of characters in the information log for
@var{shader} including the null termination character (i.e., the size of
-the character buffer required to store the information log). If
+the character buffer required to store the information log). If
@var{shader} has no information log, a value of 0 is returned.
@item @code{GL_SHADER_SOURCE_LENGTH}
@var{params} returns the length of the concatenation of the source
strings that make up the shader source for the @var{shader}, including
-the null termination character. (i.e., the size of the character buffer
-required to store the shader source). If no source code exists, 0 is
+the null termination character. (i.e., the size of the character buffer
+required to store the shader source). If no source code exists, 0 is
returned.
@end table
@end table
@code{glGetString} returns a pointer to a static string describing some
-aspect of the current GL connection. @var{name} can be one of the
+aspect of the current GL connection. @var{name} can be one of the
following:
@table @asis
@item @code{GL_VENDOR}
-Returns the company responsible for this GL implementation. This name
+Returns the company responsible for this GL implementation. This name
does not change from release to release.
@item @code{GL_RENDERER}
-Returns the name of the renderer. This name is typically specific to a
-particular configuration of a hardware platform. It does not change from
-release to release.
+Returns the name of the renderer. This name is typically specific to a
+particular configuration of a hardware platform. It does not change
+from release to release.
@item @code{GL_VERSION}
Because the GL does not include queries for the performance
characteristics of an implementation, some applications are written to
recognize known platforms and modify their GL usage based on known
-performance characteristics of these platforms. Strings @code{GL_VENDOR}
-and @code{GL_RENDERER} together uniquely specify a platform. They do not
-change from release to release and should be used by
-platform-recognition algorithms.
+performance characteristics of these platforms. Strings
+@code{GL_VENDOR} and @code{GL_RENDERER} together uniquely specify a
+platform. They do not change from release to release and should be used
+by platform-recognition algorithms.
Some applications want to make use of features that are not part of the
-standard GL. These features may be implemented as extensions to the
-standard GL. The @code{GL_EXTENSIONS} string is a space-separated list
-of supported GL extensions. (Extension names never contain a space
+standard GL. These features may be implemented as extensions to the
+standard GL. The @code{GL_EXTENSIONS} string is a space-separated list
+of supported GL extensions. (Extension names never contain a space
character.)
The @code{GL_VERSION} and @code{GL_SHADING_LANGUAGE_VERSION} strings
-begin with a version number. The version number uses one of these forms:
+begin with a version number. The version number uses one of these
+forms:
@var{major_number.minor_number}@var{major_number.minor_number.release_number}
-Vendor-specific information may follow the version number. Its format
+Vendor-specific information may follow the version number. Its format
depends on the implementation, but a space always separates the version
number and the vendor-specific information.
@table @asis
@item @var{target}
-Specifies a texture environment. May be @code{GL_TEXTURE_ENV},
+Specifies a texture environment. May be @code{GL_TEXTURE_ENV},
@code{GL_TEXTURE_FILTER_CONTROL}, or @code{GL_POINT_SPRITE}.
@item @var{pname}
-Specifies the symbolic name of a texture environment parameter. Accepted
+Specifies the symbolic name of a texture environment parameter. Accepted
values are @code{GL_TEXTURE_ENV_MODE}, @code{GL_TEXTURE_ENV_COLOR},
@code{GL_TEXTURE_LOD_BIAS}, @code{GL_COMBINE_RGB},
@code{GL_COMBINE_ALPHA}, @code{GL_SRC0_RGB}, @code{GL_SRC1_RGB},
@end table
@code{glGetTexEnv} returns in @var{params} selected values of a texture
-environment that was specified with @code{glTexEnv}. @var{target}
+environment that was specified with @code{glTexEnv}. @var{target}
specifies a texture environment.
When @var{target} is @code{GL_TEXTURE_FILTER_CONTROL}, @var{pname} must
-be @code{GL_TEXTURE_LOD_BIAS}. When @var{target} is
+be @code{GL_TEXTURE_LOD_BIAS}. When @var{target} is
@code{GL_POINT_SPRITE}, @var{pname} must be @code{GL_COORD_REPLACE}.
When @var{target} is @code{GL_TEXTURE_ENV}, @var{pname} can be
@code{GL_TEXTURE_ENV_MODE}, @code{GL_TEXTURE_ENV_COLOR},
@table @asis
@item @code{GL_TEXTURE_ENV_MODE}
@var{params} returns the single-valued texture environment mode, a
-symbolic constant. The initial value is @code{GL_MODULATE}.
+symbolic constant. The initial value is @code{GL_MODULATE}.
@item @code{GL_TEXTURE_ENV_COLOR}
@var{params} returns four integer or floating-point values that are the
-texture environment color. Integer values, when requested, are linearly
+texture environment color. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0
maps to the most positive representable integer, and @r{-1.0} maps to
-the most negative representable integer. The initial value is (0, 0, 0,
+the most negative representable integer. The initial value is (0, 0, 0,
0).
@item @code{GL_TEXTURE_LOD_BIAS}
@var{params} returns a single floating-point value that is the texture
-level-of-detail bias. The initial value is 0.
+level-of-detail bias. The initial value is 0.
@item @code{GL_COMBINE_RGB}
@var{params} returns a single symbolic constant value representing the
-current RGB combine mode. The initial value is @code{GL_MODULATE}.
+current RGB combine mode. The initial value is @code{GL_MODULATE}.
@item @code{GL_COMBINE_ALPHA}
@var{params} returns a single symbolic constant value representing the
-current alpha combine mode. The initial value is @code{GL_MODULATE}.
+current alpha combine mode. The initial value is @code{GL_MODULATE}.
@item @code{GL_SRC0_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner zero's RGB source. The initial value is
+texture combiner zero's RGB source. The initial value is
@code{GL_TEXTURE}.
@item @code{GL_SRC1_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner one's RGB source. The initial value is
+texture combiner one's RGB source. The initial value is
@code{GL_PREVIOUS}.
@item @code{GL_SRC2_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner two's RGB source. The initial value is
+texture combiner two's RGB source. The initial value is
@code{GL_CONSTANT}.
@item @code{GL_SRC0_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner zero's alpha source. The initial value is
+texture combiner zero's alpha source. The initial value is
@code{GL_TEXTURE}.
@item @code{GL_SRC1_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner one's alpha source. The initial value is
+texture combiner one's alpha source. The initial value is
@code{GL_PREVIOUS}.
@item @code{GL_SRC2_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner two's alpha source. The initial value is
+texture combiner two's alpha source. The initial value is
@code{GL_CONSTANT}.
@item @code{GL_OPERAND0_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner zero's RGB operand. The initial value is
+texture combiner zero's RGB operand. The initial value is
@code{GL_SRC_COLOR}.
@item @code{GL_OPERAND1_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner one's RGB operand. The initial value is
+texture combiner one's RGB operand. The initial value is
@code{GL_SRC_COLOR}.
@item @code{GL_OPERAND2_RGB}
@var{params} returns a single symbolic constant value representing the
-texture combiner two's RGB operand. The initial value is
+texture combiner two's RGB operand. The initial value is
@code{GL_SRC_ALPHA}.
@item @code{GL_OPERAND0_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner zero's alpha operand. The initial value is
+texture combiner zero's alpha operand. The initial value is
@code{GL_SRC_ALPHA}.
@item @code{GL_OPERAND1_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner one's alpha operand. The initial value is
+texture combiner one's alpha operand. The initial value is
@code{GL_SRC_ALPHA}.
@item @code{GL_OPERAND2_ALPHA}
@var{params} returns a single symbolic constant value representing the
-texture combiner two's alpha operand. The initial value is
+texture combiner two's alpha operand. The initial value is
@code{GL_SRC_ALPHA}.
@item @code{GL_RGB_SCALE}
@var{params} returns a single floating-point value representing the
-current RGB texture combiner scaling factor. The initial value is 1.0.
+current RGB texture combiner scaling factor. The initial value is 1.0.
@item @code{GL_ALPHA_SCALE}
@var{params} returns a single floating-point value representing the
-current alpha texture combiner scaling factor. The initial value is 1.0.
+current alpha texture combiner scaling factor. The initial value is
+1.0.
@item @code{GL_COORD_REPLACE}
@var{params} returns a single boolean value representing the current
-point sprite texture coordinate replacement enable state. The initial
+point sprite texture coordinate replacement enable state. The initial
value is @code{GL_FALSE}.
@end table
@table @asis
@item @var{coord}
-Specifies a texture coordinate. Must be @code{GL_S}, @code{GL_T},
+Specifies a texture coordinate. Must be @code{GL_S}, @code{GL_T},
@code{GL_R}, or @code{GL_Q}.
@item @var{pname}
-Specifies the symbolic name of the value(s) to be returned. Must be
+Specifies the symbolic name of the value(s) to be returned. Must be
either @code{GL_TEXTURE_GEN_MODE} or the name of one of the texture
generation plane equations: @code{GL_OBJECT_PLANE} or
@code{GL_EYE_PLANE}.
@code{glGetTexGen} returns in @var{params} selected parameters of a
texture coordinate generation function that was specified using
-@code{glTexGen}. @var{coord} names one of the (@var{s}, @var{t},
+@code{glTexGen}. @var{coord} names one of the (@var{s}, @var{t},
@var{r}, @var{q}) texture coordinates, using the symbolic constant
@code{GL_S}, @code{GL_T}, @code{GL_R}, or @code{GL_Q}.
@table @asis
@item @code{GL_TEXTURE_GEN_MODE}
@var{params} returns the single-valued texture generation function, a
-symbolic constant. The initial value is @code{GL_EYE_LINEAR}.
+symbolic constant. The initial value is @code{GL_EYE_LINEAR}.
@item @code{GL_OBJECT_PLANE}
@var{params} returns the four plane equation coefficients that specify
-object linear-coordinate generation. Integer values, when requested, are
-mapped directly from the internal floating-point representation.
+object linear-coordinate generation. Integer values, when requested,
+are mapped directly from the internal floating-point representation.
@item @code{GL_EYE_PLANE}
@var{params} returns the four plane equation coefficients that specify
-eye linear-coordinate generation. Integer values, when requested, are
-mapped directly from the internal floating-point representation. The
-returned values are those maintained in eye coordinates. They are not
+eye linear-coordinate generation. Integer values, when requested, are
+mapped directly from the internal floating-point representation. The
+returned values are those maintained in eye coordinates. They are not
equal to the values specified using @code{glTexGen}, unless the
modelview matrix was identity when @code{glTexGen} was called.
@table @asis
@item @var{target}
-Specifies which texture is to be obtained. @code{GL_TEXTURE_1D},
+Specifies which texture is to be obtained. @code{GL_TEXTURE_1D},
@code{GL_TEXTURE_2D}, @code{GL_TEXTURE_3D},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z} are accepted.
@item @var{level}
-Specifies the level-of-detail number of the desired image. Level 0 is
-the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
+Specifies the level-of-detail number of the desired image. Level 0 is
+the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
reduction image.
@item @var{format}
-Specifies a pixel format for the returned data. The supported formats
+Specifies a pixel format for the returned data. The supported formats
are @code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE}, @code{GL_ALPHA},
@code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA}, @code{GL_BGRA},
@code{GL_LUMINANCE}, and @code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies a pixel type for the returned data. The supported types are
+Specifies a pixel type for the returned data. The supported types are
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_UNSIGNED_SHORT},
@code{GL_SHORT}, @code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{img}
-Returns the texture image. Should be a pointer to an array of the type
+Returns the texture image. Should be a pointer to an array of the type
specified by @var{type}.
@end table
specified by @code{glTexImage1D} (@code{GL_TEXTURE_1D}),
@code{glTexImage2D} (@code{GL_TEXTURE_2D} or any of
@code{GL_TEXTURE_CUBE_MAP_*}), or @code{glTexImage3D}
-(@code{GL_TEXTURE_3D}). @var{level} specifies the level-of-detail number
-of the desired image. @var{format} and @var{type} specify the format and
-type of the desired image array. See the reference pages
+(@code{GL_TEXTURE_3D}). @var{level} specifies the level-of-detail
+number of the desired image. @var{format} and @var{type} specify the
+format and type of the desired image array. See the reference pages
@code{glTexImage1D} and @code{glDrawPixels} for a description of the
acceptable values for the @var{format} and @var{type} parameters,
respectively.
To understand the operation of @code{glGetTexImage}, consider the
selected internal four-component texture image to be an RGBA color
-buffer the size of the image. The semantics of @code{glGetTexImage} are
+buffer the size of the image. The semantics of @code{glGetTexImage} are
then identical to those of @code{glReadPixels}, with the exception that
no pixel transfer operations are performed, when called with the same
@var{format} and @var{type}, with @var{x} and @var{y} set to 0,
@var{width} set to the width of the texture image (including border if
one was specified), and @var{height} set to 1 for 1D images, or to the
height of the texture image (including border if one was specified) for
-2D images. Because the internal texture image is an RGBA image, pixel
+2D images. Because the internal texture image is an RGBA image, pixel
formats @code{GL_COLOR_INDEX}, @code{GL_STENCIL_INDEX}, and
@code{GL_DEPTH_COMPONENT} are not accepted, and pixel type
@code{GL_BITMAP} is not accepted.
If the selected texture image does not contain four components, the
-following mappings are applied. Single-component textures are treated as
-RGBA buffers with red set to the single-component value, green set to 0,
-blue set to 0, and alpha set to 1. Two-component textures are treated as
-RGBA buffers with red set to the value of component zero, alpha set to
-the value of component one, and green and blue set to 0. Finally,
-three-component textures are treated as RGBA buffers with red set to
-component zero, green set to component one, blue set to component two,
-and alpha set to 1.
+following mappings are applied. Single-component textures are treated
+as RGBA buffers with red set to the single-component value, green set to
+0, blue set to 0, and alpha set to 1. Two-component textures are
+treated as RGBA buffers with red set to the value of component zero,
+alpha set to the value of component one, and green and blue set to 0.
+Finally, three-component textures are treated as RGBA buffers with red
+set to component zero, green set to component one, blue set to component
+two, and alpha set to 1.
To determine the required size of @var{img}, use
@code{glGetTexLevelParameter} to determine the dimensions of the
@code{GL_PROXY_TEXTURE_CUBE_MAP}.
@item @var{level}
-Specifies the level-of-detail number of the desired image. Level 0 is
-the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
+Specifies the level-of-detail number of the desired image. Level 0 is
+the base image level. Level @r{@var{n}} is the @r{@var{n}}th mipmap
reduction image.
@item @var{pname}
@code{GL_PROXY_TEXTURE_CUBE_MAP}.
@code{GL_MAX_TEXTURE_SIZE}, and @code{GL_MAX_3D_TEXTURE_SIZE} are not
-really descriptive enough. It has to report the largest square texture
+really descriptive enough. It has to report the largest square texture
image that can be accommodated with mipmaps and borders, but a long
skinny texture, or a texture without mipmaps and borders, may easily fit
-in texture memory. The proxy targets allow the user to more accurately
+in texture memory. The proxy targets allow the user to more accurately
query whether the GL can accommodate a texture of a given configuration.
If the texture cannot be accommodated, the texture state variables,
which may be queried with @code{glGetTexLevelParameter}, are set to 0.
@var{params} returns a single value, the width of the texture image.
-This value includes the border of the texture image. The initial value
+This value includes the border of the texture image. The initial value
is 0.
@item @code{GL_TEXTURE_HEIGHT}
@var{params} returns a single value, the height of the texture image.
-This value includes the border of the texture image. The initial value
+This value includes the border of the texture image. The initial value
is 0.
@item @code{GL_TEXTURE_DEPTH}
@var{params} returns a single value, the depth of the texture image.
-This value includes the border of the texture image. The initial value
+This value includes the border of the texture image. The initial value
is 0.
@item @code{GL_TEXTURE_INTERNAL_FORMAT}
@var{params} returns a single value, the width in pixels of the border
-of the texture image. The initial value is 0.
+of the texture image. The initial value is 0.
@item @code{GL_TEXTURE_RED_SIZE},
@item @code{GL_TEXTURE_GREEN_SIZE},
@item @code{GL_TEXTURE_DEPTH_SIZE}
-The internal storage resolution of an individual component. The
+The internal storage resolution of an individual component. The
resolution chosen by the GL will be a close match for the resolution
requested by the user with the component argument of
@code{glTexImage1D}, @code{glTexImage2D}, @code{glTexImage3D},
-@code{glCopyTexImage1D}, and @code{glCopyTexImage2D}. The initial value
+@code{glCopyTexImage1D}, and @code{glCopyTexImage2D}. The initial value
is 0.
@item @code{GL_TEXTURE_COMPRESSED}
@var{params} returns a single boolean value indicating if the texture
-image is stored in a compressed internal format. The initiali value is
+image is stored in a compressed internal format. The initiali value is
@code{GL_FALSE}.
@item @code{GL_TEXTURE_COMPRESSED_IMAGE_SIZE}
@table @asis
@item @var{target}
-Specifies the symbolic name of the target texture. @code{GL_TEXTURE_1D},
+Specifies the symbolic name of the target texture. @code{GL_TEXTURE_1D},
@code{GL_TEXTURE_2D}, @code{GL_TEXTURE_3D}, and
@code{GL_TEXTURE_CUBE_MAP} are accepted.
@end table
@code{glGetTexParameter} returns in @var{params} the value or values of
-the texture parameter specified as @var{pname}. @var{target} defines the
-target texture, either @code{GL_TEXTURE_1D}, @code{GL_TEXTURE_2D},
+the texture parameter specified as @var{pname}. @var{target} defines
+the target texture, either @code{GL_TEXTURE_1D}, @code{GL_TEXTURE_2D},
@code{GL_TEXTURE_3D}, or @code{GL_TEXTURE_CUBE_MAP}, to specify one-,
-two-, or three-dimensional or cube-mapped texturing. @var{pname} accepts
-the same symbols as @code{glTexParameter}, with the same
+two-, or three-dimensional or cube-mapped texturing. @var{pname}
+accepts the same symbols as @code{glTexParameter}, with the same
interpretations:
@table @asis
@item @code{GL_TEXTURE_MAG_FILTER}
Returns the single-valued texture magnification filter, a symbolic
-constant. The initial value is @code{GL_LINEAR}.
+constant. The initial value is @code{GL_LINEAR}.
@item @code{GL_TEXTURE_MIN_FILTER}
Returns the single-valued texture minification filter, a symbolic
-constant. The initial value is @code{GL_NEAREST_MIPMAP_LINEAR}.
+constant. The initial value is @code{GL_NEAREST_MIPMAP_LINEAR}.
@item @code{GL_TEXTURE_MIN_LOD}
-Returns the single-valued texture minimum level-of-detail value. The
+Returns the single-valued texture minimum level-of-detail value. The
initial value is @r{-1000}.
@item @code{GL_TEXTURE_MAX_LOD}
-Returns the single-valued texture maximum level-of-detail value. The
+Returns the single-valued texture maximum level-of-detail value. The
initial value is 1000.
@item @code{GL_TEXTURE_BASE_LEVEL}
-Returns the single-valued base texture mipmap level. The initial value
+Returns the single-valued base texture mipmap level. The initial value
is 0.
@item @code{GL_TEXTURE_MAX_LEVEL}
-Returns the single-valued maximum texture mipmap array level. The
+Returns the single-valued maximum texture mipmap array level. The
initial value is 1000.
@item @code{GL_TEXTURE_WRAP_S}
Returns the single-valued wrapping function for texture coordinate
-@r{@var{s}}, a symbolic constant. The initial value is @code{GL_REPEAT}.
+@r{@var{s}}, a symbolic constant. The initial value is
+@code{GL_REPEAT}.
@item @code{GL_TEXTURE_WRAP_T}
Returns the single-valued wrapping function for texture coordinate
-@r{@var{t}}, a symbolic constant. The initial value is @code{GL_REPEAT}.
+@r{@var{t}}, a symbolic constant. The initial value is
+@code{GL_REPEAT}.
@item @code{GL_TEXTURE_WRAP_R}
Returns the single-valued wrapping function for texture coordinate
-@r{@var{r}}, a symbolic constant. The initial value is @code{GL_REPEAT}.
+@r{@var{r}}, a symbolic constant. The initial value is
+@code{GL_REPEAT}.
@item @code{GL_TEXTURE_BORDER_COLOR}
Returns four integer or floating-point numbers that comprise the RGBA
-color of the texture border. Floating-point values are returned in the
-range @r{[0,1]}. Integer values are returned as a linear mapping of the
+color of the texture border. Floating-point values are returned in the
+range @r{[0,1]}. Integer values are returned as a linear mapping of the
internal floating-point representation such that 1.0 maps to the most
positive representable integer and @r{-1.0} maps to the most negative
-representable integer. The initial value is (0, 0, 0, 0).
+representable integer. The initial value is (0, 0, 0, 0).
@item @code{GL_TEXTURE_PRIORITY}
Returns the residence priority of the target texture (or the named
-texture bound to it). The initial value is 1. See
+texture bound to it). The initial value is 1. See
@code{glPrioritizeTextures}.
@item @code{GL_TEXTURE_RESIDENT}
-Returns the residence status of the target texture. If the value
+Returns the residence status of the target texture. If the value
returned in @var{params} is @code{GL_TRUE}, the texture is resident in
-texture memory. See @code{glAreTexturesResident}.
+texture memory. See @code{glAreTexturesResident}.
@item @code{GL_TEXTURE_COMPARE_MODE}
Returns a single-valued texture comparison mode, a symbolic constant.
-The initial value is @code{GL_NONE}. See @code{glTexParameter}.
+The initial value is @code{GL_NONE}. See @code{glTexParameter}.
@item @code{GL_TEXTURE_COMPARE_FUNC}
Returns a single-valued texture comparison function, a symbolic
-constant. The initial value is @code{GL_LEQUAL}. See
+constant. The initial value is @code{GL_LEQUAL}. See
@code{glTexParameter}.
@item @code{GL_DEPTH_TEXTURE_MODE}
Returns a single-valued texture format indicating how the depth values
-should be converted into color components. The initial value is
-@code{GL_LUMINANCE}. See @code{glTexParameter}.
+should be converted into color components. The initial value is
+@code{GL_LUMINANCE}. See @code{glTexParameter}.
@item @code{GL_GENERATE_MIPMAP}
Returns a single boolean value indicating if automatic mipmap level
-updates are enabled. See @code{glTexParameter}.
+updates are enabled. See @code{glTexParameter}.
@end table
@code{glGetUniformLocation } returns an integer that represents the
location of a specific uniform variable within a program object.
@var{name} must be a null terminated string that contains no white
-space. @var{name} must be an active uniform variable name in
+space. @var{name} must be an active uniform variable name in
@var{program} that is not a structure, an array of structures, or a
-subcomponent of a vector or a matrix. This function returns -1 if
+subcomponent of a vector or a matrix. This function returns -1 if
@var{name} does not correspond to an active uniform variable in
@var{program} or if @var{name} starts with the reserved prefix "gl_".
Uniform variables that are structures or arrays of structures may be
queried by calling @code{glGetUniformLocation} for each field within the
-structure. The array element operator "[]" and the structure field
+structure. The array element operator "[]" and the structure field
operator "." may be used in @var{name} in order to select elements
-within an array or fields within a structure. The result of using these
+within an array or fields within a structure. The result of using these
operators is not allowed to be another structure, an array of
-structures, or a subcomponent of a vector or a matrix. Except if the
+structures, or a subcomponent of a vector or a matrix. Except if the
last part of @var{name} indicates a uniform variable array, the location
of the first element of an array can be retrieved by using the name of
the array, or by using the name appended by "[0]".
The actual locations assigned to uniform variables are not known until
-the program object is linked successfully. After linking has occurred,
+the program object is linked successfully. After linking has occurred,
the command @code{glGetUniformLocation} can be used to obtain the
-location of a uniform variable. This location value can then be passed
+location of a uniform variable. This location value can then be passed
to @code{glUniform} to set the value of the uniform variable or to
@code{glGetUniform} in order to query the current value of the uniform
-variable. After a program object has been linked successfully, the index
-values for uniform variables remain fixed until the next link command
-occurs. Uniform variable locations and values can only be queried after
-a link if the link was successful.
+variable. After a program object has been linked successfully, the
+index values for uniform variables remain fixed until the next link
+command occurs. Uniform variable locations and values can only be
+queried after a link if the link was successful.
@code{GL_INVALID_VALUE} is generated if @var{program} is not a value
generated by OpenGL.
@end table
@code{glGetUniform} returns in @var{params} the value(s) of the
-specified uniform variable. The type of the uniform variable specified
-by @var{location} determines the number of values returned. If the
+specified uniform variable. The type of the uniform variable specified
+by @var{location} determines the number of values returned. If the
uniform variable is defined in the shader as a boolean, int, or float, a
-single value will be returned. If it is defined as a vec2, ivec2, or
-bvec2, two values will be returned. If it is defined as a vec3, ivec3,
-or bvec3, three values will be returned, and so on. To query values
+single value will be returned. If it is defined as a vec2, ivec2, or
+bvec2, two values will be returned. If it is defined as a vec3, ivec3,
+or bvec3, three values will be returned, and so on. To query values
stored in uniform variables declared as arrays, call @code{glGetUniform}
-for each element of the array. To query values stored in uniform
+for each element of the array. To query values stored in uniform
variables declared as structures, call @code{glGetUniform} for each
-field in the structure. The values for uniform variables declared as a
+field in the structure. The values for uniform variables declared as a
matrix will be returned in column major order.
The locations assigned to uniform variables are not known until the
-program object is linked. After linking has occurred, the command
+program object is linked. After linking has occurred, the command
@code{glGetUniformLocation} can be used to obtain the location of a
-uniform variable. This location value can then be passed to
+uniform variable. This location value can then be passed to
@code{glGetUniform} in order to query the current value of the uniform
-variable. After a program object has been linked successfully, the index
-values for uniform variables remain fixed until the next link command
-occurs. The uniform variable values can only be queried after a link if
-the link was successful.
+variable. After a program object has been linked successfully, the
+index values for uniform variables remain fixed until the next link
+command occurs. The uniform variable values can only be queried after a
+link if the link was successful.
@code{GL_INVALID_VALUE} is generated if @var{program} is not a value
generated by OpenGL.
@item @var{pname}
Specifies the symbolic name of the generic vertex attribute parameter to
-be returned. Must be @code{GL_VERTEX_ATTRIB_ARRAY_POINTER}.
+be returned. Must be @code{GL_VERTEX_ATTRIB_ARRAY_POINTER}.
@item @var{pointer}
Returns the pointer value.
@item @var{pname}
Specifies the symbolic name of the vertex attribute parameter to be
-queried. Accepted values are
+queried. Accepted values are
@code{GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING},
@code{GL_VERTEX_ATTRIB_ARRAY_ENABLED},
@code{GL_VERTEX_ATTRIB_ARRAY_SIZE},
@end table
@code{glGetVertexAttrib} returns in @var{params} the value of a generic
-vertex attribute parameter. The generic vertex attribute to be queried
+vertex attribute parameter. The generic vertex attribute to be queried
is specified by @var{index}, and the parameter to be queried is
specified by @var{pname}.
@var{params} returns a single value, the name of the buffer object
currently bound to the binding point corresponding to generic vertex
-attribute array @var{index}. If no buffer object is bound, 0 is
-returned. The initial value is 0.
+attribute array @var{index}. If no buffer object is bound, 0 is
+returned. The initial value is 0.
@item @code{GL_VERTEX_ATTRIB_ARRAY_ENABLED}
@var{params} returns a single value that is non-zero (true) if the
vertex attribute array for @var{index} is enabled and 0 (false) if it is
-disabled. The initial value is @code{GL_FALSE}.
+disabled. The initial value is @code{GL_FALSE}.
@item @code{GL_VERTEX_ATTRIB_ARRAY_SIZE}
@var{params} returns a single value, the size of the vertex attribute
-array for @var{index}. The size is the number of values for each element
-of the vertex attribute array, and it will be 1, 2, 3, or 4. The initial
-value is 4.
+array for @var{index}. The size is the number of values for each
+element of the vertex attribute array, and it will be 1, 2, 3, or 4. The
+initial value is 4.
@item @code{GL_VERTEX_ATTRIB_ARRAY_STRIDE}
@var{params} returns a single value, the array stride for (number of
bytes between successive elements in) the vertex attribute array for
-@var{index}. A value of 0 indicates that the array elements are stored
-sequentially in memory. The initial value is 0.
+@var{index}. A value of 0 indicates that the array elements are stored
+sequentially in memory. The initial value is 0.
@item @code{GL_VERTEX_ATTRIB_ARRAY_TYPE}
@var{params} returns a single value, a symbolic constant indicating the
-array type for the vertex attribute array for @var{index}. Possible
+array type for the vertex attribute array for @var{index}. Possible
values are @code{GL_BYTE}, @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT},
@code{GL_UNSIGNED_SHORT}, @code{GL_INT}, @code{GL_UNSIGNED_INT},
-@code{GL_FLOAT}, and @code{GL_DOUBLE}. The initial value is
+@code{GL_FLOAT}, and @code{GL_DOUBLE}. The initial value is
@code{GL_FLOAT}.
@item @code{GL_VERTEX_ATTRIB_ARRAY_NORMALIZED}
@var{params} returns a single value that is non-zero (true) if
fixed-point data types for the vertex attribute array indicated by
@var{index} are normalized when they are converted to floating point,
-and 0 (false) otherwise. The initial value is @code{GL_FALSE}.
+and 0 (false) otherwise. The initial value is @code{GL_FALSE}.
@item @code{GL_CURRENT_VERTEX_ATTRIB}
@var{params} returns four values that represent the current value for
-the generic vertex attribute specified by index. Generic vertex
+the generic vertex attribute specified by index. Generic vertex
attribute 0 is unique in that it has no current state, so an error will
-be generated if @var{index} is 0. The initial value for all other
+be generated if @var{index} is 0. The initial value for all other
generic vertex attributes is (0,0,0,1).
@end table
@table @asis
@item @var{pname}
-Specifies the parameter value to be returned. The symbolic constants in
+Specifies the parameter value to be returned. The symbolic constants in
the list below are accepted.
@item @var{params}
type in which to place the returned data.
Type conversion is performed if @var{params} has a different type than
-the state variable value being requested. If @code{glGetBooleanv} is
+the state variable value being requested. If @code{glGetBooleanv} is
called, a floating-point (or integer) value is converted to
-@code{GL_FALSE} if and only if it is 0.0 (or 0). Otherwise, it is
-converted to @code{GL_TRUE}. If @code{glGetIntegerv} is called, boolean
+@code{GL_FALSE} if and only if it is 0.0 (or 0). Otherwise, it is
+converted to @code{GL_TRUE}. If @code{glGetIntegerv} is called, boolean
values are returned as @code{GL_TRUE} or @code{GL_FALSE}, and most
floating-point values are rounded to the nearest integer value.
Floating-point colors and normals, however, are returned with a linear
mapping that maps 1.0 to the most positive representable integer value
-and @r{-1.0} to the most negative representable integer value. If
+and @r{-1.0} to the most negative representable integer value. If
@code{glGetFloatv} or @code{glGetDoublev} is called, boolean values are
returned as @code{GL_TRUE} or @code{GL_FALSE}, and integer values are
converted to floating-point values.
@var{params} returns four values: the red, green, blue, and alpha values
-used to clear the accumulation buffer. Integer values, if requested, are
-linearly mapped from the internal floating-point representation such
+used to clear the accumulation buffer. Integer values, if requested,
+are linearly mapped from the internal floating-point representation such
that 1.0 returns the most positive representable integer value, and
-@r{-1.0} returns the most negative representable integer value. The
-initial value is (0, 0, 0, 0). See @code{glClearAccum}.
+@r{-1.0} returns the most negative representable integer value. The
+initial value is (0, 0, 0, 0). See @code{glClearAccum}.
@item @code{GL_ACCUM_GREEN_BITS}
@var{params} returns a single value indicating the active multitexture
-unit. The initial value is @code{GL_TEXTURE0}. See
+unit. The initial value is @code{GL_TEXTURE0}. See
@code{glActiveTexture}.
@item @code{GL_ALIASED_POINT_SIZE_RANGE}
@var{params} returns one value, the alpha bias factor used during pixel
-transfers. The initial value is 0. See @code{glPixelTransfer}.
+transfers. The initial value is 0. See @code{glPixelTransfer}.
@item @code{GL_ALPHA_BITS}
@var{params} returns one value, the alpha scale factor used during pixel
-transfers. The initial value is 1. See @code{glPixelTransfer}.
+transfers. The initial value is 1. See @code{glPixelTransfer}.
@item @code{GL_ALPHA_TEST}
@var{params} returns a single boolean value indicating whether alpha
-testing of fragments is enabled. The initial value is @code{GL_FALSE}.
+testing of fragments is enabled. The initial value is @code{GL_FALSE}.
See @code{glAlphaFunc}.
@item @code{GL_ALPHA_TEST_FUNC}@var{params} returns one value,
-the symbolic name of the alpha test function. The initial value is
-@code{GL_ALWAYS}. See @code{glAlphaFunc}.
+the symbolic name of the alpha test function. The initial value is
+@code{GL_ALWAYS}. See @code{glAlphaFunc}.
@item @code{GL_ALPHA_TEST_REF}
@var{params} returns one value, the reference value for the alpha test.
-The initial value is 0. See @code{glAlphaFunc}. An integer value, if
+The initial value is 0. See @code{glAlphaFunc}. An integer value, if
requested, is linearly mapped from the internal floating-point
representation such that 1.0 returns the most positive representable
integer value, and @r{-1.0} returns the most negative representable
@var{params} returns a single value, the name of the buffer object
-currently bound to the target @code{GL_ARRAY_BUFFER}. If no buffer
-object is bound to this target, 0 is returned. The initial value is 0.
+currently bound to the target @code{GL_ARRAY_BUFFER}. If no buffer
+object is bound to this target, 0 is returned. The initial value is 0.
See @code{glBindBuffer}.
@item @code{GL_ATTRIB_STACK_DEPTH}
-@var{params} returns one value, the depth of the attribute stack. If the
-stack is empty, 0 is returned. The initial value is 0. See
+@var{params} returns one value, the depth of the attribute stack. If
+the stack is empty, 0 is returned. The initial value is 0. See
@code{glPushAttrib}.
@item @code{GL_AUTO_NORMAL}
@var{params} returns a single boolean value indicating whether 2D map
-evaluation automatically generates surface normals. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation automatically generates surface normals. The initial value
+is @code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_AUX_BUFFERS}
@var{params} returns a single boolean value indicating whether blending
-is enabled. The initial value is @code{GL_FALSE}. See
+is enabled. The initial value is @code{GL_FALSE}. See
@code{glBlendFunc}.
@item @code{GL_BLEND_COLOR}
@var{params} returns four values, the red, green, blue, and alpha values
-which are the components of the blend color. See @code{glBlendColor}.
+which are the components of the blend color. See @code{glBlendColor}.
@item @code{GL_BLEND_DST_ALPHA}
@var{params} returns one value, the symbolic constant identifying the
-alpha destination blend function. The initial value is @code{GL_ZERO}.
+alpha destination blend function. The initial value is @code{GL_ZERO}.
See @code{glBlendFunc} and @code{glBlendFuncSeparate}.
@item @code{GL_BLEND_DST_RGB}
@var{params} returns one value, the symbolic constant identifying the
-RGB destination blend function. The initial value is @code{GL_ZERO}. See
-@code{glBlendFunc} and @code{glBlendFuncSeparate}.
+RGB destination blend function. The initial value is @code{GL_ZERO}.
+See @code{glBlendFunc} and @code{glBlendFuncSeparate}.
@item @code{GL_BLEND_EQUATION_RGB}
@var{params} returns one value, a symbolic constant indicating whether
the RGB blend equation is @code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
-@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN} or @code{GL_MAX}. See
+@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN} or @code{GL_MAX}. See
@code{glBlendEquationSeparate}.
@item @code{GL_BLEND_EQUATION_ALPHA}
@var{params} returns one value, a symbolic constant indicating whether
the Alpha blend equation is @code{GL_FUNC_ADD}, @code{GL_FUNC_SUBTRACT},
-@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN} or @code{GL_MAX}. See
+@code{GL_FUNC_REVERSE_SUBTRACT}, @code{GL_MIN} or @code{GL_MAX}. See
@code{glBlendEquationSeparate}.
@item @code{GL_BLEND_SRC_ALPHA}
@var{params} returns one value, the symbolic constant identifying the
-alpha source blend function. The initial value is @code{GL_ONE}. See
+alpha source blend function. The initial value is @code{GL_ONE}. See
@code{glBlendFunc} and @code{glBlendFuncSeparate}.
@item @code{GL_BLEND_SRC_RGB}
@var{params} returns one value, the symbolic constant identifying the
-RGB source blend function. The initial value is @code{GL_ONE}. See
+RGB source blend function. The initial value is @code{GL_ONE}. See
@code{glBlendFunc} and @code{glBlendFuncSeparate}.
@item @code{GL_BLUE_BIAS}
@var{params} returns one value, the blue bias factor used during pixel
-transfers. The initial value is 0. See @code{glPixelTransfer}.
+transfers. The initial value is 0. See @code{glPixelTransfer}.
@item @code{GL_BLUE_BITS}
@var{params} returns one value, the blue scale factor used during pixel
-transfers. The initial value is 1. See @code{glPixelTransfer}.
+transfers. The initial value is 1. See @code{glPixelTransfer}.
@item @code{GL_CLIENT_ACTIVE_TEXTURE}
@var{params} returns a single integer value indicating the current
-client active multitexture unit. The initial value is
-@code{GL_TEXTURE0}. See @code{glClientActiveTexture}.
+client active multitexture unit. The initial value is
+@code{GL_TEXTURE0}. See @code{glClientActiveTexture}.
@item @code{GL_CLIENT_ATTRIB_STACK_DEPTH}
@var{params} returns one value indicating the depth of the attribute
-stack. The initial value is 0. See @code{glPushClientAttrib}.
+stack. The initial value is 0. See @code{glPushClientAttrib}.
@item @code{GL_CLIP_PLANE}@var{i}
@var{params} returns a single boolean value indicating whether the
-specified clipping plane is enabled. The initial value is
-@code{GL_FALSE}. See @code{glClipPlane}.
+specified clipping plane is enabled. The initial value is
+@code{GL_FALSE}. See @code{glClipPlane}.
@item @code{GL_COLOR_ARRAY}
@var{params} returns a single boolean value indicating whether the color
-array is enabled. The initial value is @code{GL_FALSE}. See
+array is enabled. The initial value is @code{GL_FALSE}. See
@code{glColorPointer}.
@item @code{GL_COLOR_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the color array. This buffer object would have been
+associated with the color array. This buffer object would have been
bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glColorPointer}. If no buffer object was bound to
-this target, 0 is returned. The initial value is 0. See
+recent call to @code{glColorPointer}. If no buffer object was bound to
+this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_COLOR_ARRAY_SIZE}
@var{params} returns one value, the number of components per color in
-the color array. The initial value is 4. See @code{glColorPointer}.
+the color array. The initial value is 4. See @code{glColorPointer}.
@item @code{GL_COLOR_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-colors in the color array. The initial value is 0. See
+colors in the color array. The initial value is 0. See
@code{glColorPointer}.
@item @code{GL_COLOR_ARRAY_TYPE}
@var{params} returns one value, the data type of each component in the
-color array. The initial value is @code{GL_FLOAT}. See
+color array. The initial value is @code{GL_FLOAT}. See
@code{glColorPointer}.
@item @code{GL_COLOR_CLEAR_VALUE}
@var{params} returns four values: the red, green, blue, and alpha values
-used to clear the color buffers. Integer values, if requested, are
+used to clear the color buffers. Integer values, if requested, are
linearly mapped from the internal floating-point representation such
that 1.0 returns the most positive representable integer value, and
-@r{-1.0} returns the most negative representable integer value. The
-initial value is (0, 0, 0, 0). See @code{glClearColor}.
+@r{-1.0} returns the most negative representable integer value. The
+initial value is (0, 0, 0, 0). See @code{glClearColor}.
@item @code{GL_COLOR_LOGIC_OP}
@var{params} returns a single boolean value indicating whether a
fragment's RGBA color values are merged into the framebuffer using a
-logical operation. The initial value is @code{GL_FALSE}. See
+logical operation. The initial value is @code{GL_FALSE}. See
@code{glLogicOp}.
@item @code{GL_COLOR_MATERIAL}
@var{params} returns a single boolean value indicating whether one or
-more material parameters are tracking the current color. The initial
-value is @code{GL_FALSE}. See @code{glColorMaterial}.
+more material parameters are tracking the current color. The initial
+value is @code{GL_FALSE}. See @code{glColorMaterial}.
@item @code{GL_COLOR_MATERIAL_FACE}
@var{params} returns one value, a symbolic constant indicating which
-materials have a parameter that is tracking the current color. The
-initial value is @code{GL_FRONT_AND_BACK}. See @code{glColorMaterial}.
+materials have a parameter that is tracking the current color. The
+initial value is @code{GL_FRONT_AND_BACK}. See @code{glColorMaterial}.
@item @code{GL_COLOR_MATERIAL_PARAMETER}
@var{params} returns one value, a symbolic constant indicating which
-material parameters are tracking the current color. The initial value is
-@code{GL_AMBIENT_AND_DIFFUSE}. See @code{glColorMaterial}.
+material parameters are tracking the current color. The initial value
+is @code{GL_AMBIENT_AND_DIFFUSE}. See @code{glColorMaterial}.
@item @code{GL_COLOR_MATRIX}
@var{params} returns sixteen values: the color matrix on the top of the
-color matrix stack. Initially this matrix is the identity matrix. See
+color matrix stack. Initially this matrix is the identity matrix. See
@code{glPushMatrix}.
@item @code{GL_COLOR_MATRIX_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-projection matrix stack. The value must be at least 2. See
+projection matrix stack. The value must be at least 2. See
@code{glPushMatrix}.
@item @code{GL_COLOR_SUM}
@var{params} returns a single boolean value indicating whether primary
-and secondary color sum is enabled. See @code{glSecondaryColor}.
+and secondary color sum is enabled. See @code{glSecondaryColor}.
@item @code{GL_COLOR_TABLE}
@var{params} returns a single boolean value indicating whether the color
-table lookup is enabled. See @code{glColorTable}.
+table lookup is enabled. See @code{glColorTable}.
@item @code{GL_COLOR_WRITEMASK}
@var{params} returns four boolean values: the red, green, blue, and
-alpha write enables for the color buffers. The initial value is
-(@code{GL_TRUE}, @code{GL_TRUE}, @code{GL_TRUE}, @code{GL_TRUE}). See
+alpha write enables for the color buffers. The initial value is
+(@code{GL_TRUE}, @code{GL_TRUE}, @code{GL_TRUE}, @code{GL_TRUE}). See
@code{glColorMask}.
@item @code{GL_COMPRESSED_TEXTURE_FORMATS}
@var{params} returns a list of symbolic constants of length
@code{GL_NUM_COMPRESSED_TEXTURE_FORMATS} indicating which compressed
-texture formats are available. See @code{glCompressedTexImage2D}.
+texture formats are available. See @code{glCompressedTexImage2D}.
@item @code{GL_CONVOLUTION_1D}
@var{params} returns a single boolean value indicating whether 1D
-convolution is enabled. The initial value is @code{GL_FALSE}. See
+convolution is enabled. The initial value is @code{GL_FALSE}. See
@code{glConvolutionFilter1D}.
@item @code{GL_CONVOLUTION_2D}
@var{params} returns a single boolean value indicating whether 2D
-convolution is enabled. The initial value is @code{GL_FALSE}. See
+convolution is enabled. The initial value is @code{GL_FALSE}. See
@code{glConvolutionFilter2D}.
@item @code{GL_CULL_FACE}
@var{params} returns a single boolean value indicating whether polygon
-culling is enabled. The initial value is @code{GL_FALSE}. See
+culling is enabled. The initial value is @code{GL_FALSE}. See
@code{glCullFace}.
@item @code{GL_CULL_FACE_MODE}
@var{params} returns one value, a symbolic constant indicating which
-polygon faces are to be culled. The initial value is @code{GL_BACK}. See
-@code{glCullFace}.
+polygon faces are to be culled. The initial value is @code{GL_BACK}.
+See @code{glCullFace}.
@item @code{GL_CURRENT_COLOR}
@var{params} returns four values: the red, green, blue, and alpha values
-of the current color. Integer values, if requested, are linearly mapped
+of the current color. Integer values, if requested, are linearly mapped
from the internal floating-point representation such that 1.0 returns
the most positive representable integer value, and @r{-1.0} returns the
-most negative representable integer value. The initial value is (1, 1,
-1, 1). See @code{glColor}.
+most negative representable integer value. The initial value is (1, 1,
+1, 1). See @code{glColor}.
@item @code{GL_CURRENT_FOG_COORD}
-@var{params} returns one value, the current fog coordinate. The initial
-value is 0. See @code{glFogCoord}.
+@var{params} returns one value, the current fog coordinate. The initial
+value is 0. See @code{glFogCoord}.
@item @code{GL_CURRENT_INDEX}
-@var{params} returns one value, the current color index. The initial
-value is 1. See @code{glIndex}.
+@var{params} returns one value, the current color index. The initial
+value is 1. See @code{glIndex}.
@item @code{GL_CURRENT_NORMAL}
@var{params} returns three values: the @var{x}, @var{y}, and @var{z}
-values of the current normal. Integer values, if requested, are linearly
-mapped from the internal floating-point representation such that 1.0
-returns the most positive representable integer value, and @r{-1.0}
-returns the most negative representable integer value. The initial value
-is (0, 0, 1). See @code{glNormal}.
+values of the current normal. Integer values, if requested, are
+linearly mapped from the internal floating-point representation such
+that 1.0 returns the most positive representable integer value, and
+@r{-1.0} returns the most negative representable integer value. The
+initial value is (0, 0, 1). See @code{glNormal}.
@item @code{GL_CURRENT_PROGRAM}
@var{params} returns one value, the name of the program object that is
-currently active, or 0 if no program object is active. See
+currently active, or 0 if no program object is active. See
@code{glUseProgram}.
@item @code{GL_CURRENT_RASTER_COLOR}
@var{params} returns four values: the red, green, blue, and alpha color
-values of the current raster position. Integer values, if requested, are
-linearly mapped from the internal floating-point representation such
+values of the current raster position. Integer values, if requested,
+are linearly mapped from the internal floating-point representation such
that 1.0 returns the most positive representable integer value, and
-@r{-1.0} returns the most negative representable integer value. The
-initial value is (1, 1, 1, 1). See @code{glRasterPos}.
+@r{-1.0} returns the most negative representable integer value. The
+initial value is (1, 1, 1, 1). See @code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_DISTANCE}
@var{params} returns one value, the distance from the eye to the current
-raster position. The initial value is 0. See @code{glRasterPos}.
+raster position. The initial value is 0. See @code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_INDEX}
@var{params} returns one value, the color index of the current raster
-position. The initial value is 1. See @code{glRasterPos}.
+position. The initial value is 1. See @code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_POSITION}
@var{params} returns four values: the @var{x}, @var{y}, @var{z}, and
-@var{w} components of the current raster position. @var{x}, @var{y}, and
-@var{z} are in window coordinates, and @var{w} is in clip coordinates.
-The initial value is (0, 0, 0, 1). See @code{glRasterPos}.
+@var{w} components of the current raster position. @var{x}, @var{y},
+and @var{z} are in window coordinates, and @var{w} is in clip
+coordinates. The initial value is (0, 0, 0, 1). See
+@code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_POSITION_VALID}
@var{params} returns a single boolean value indicating whether the
-current raster position is valid. The initial value is @code{GL_TRUE}.
+current raster position is valid. The initial value is @code{GL_TRUE}.
See @code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_SECONDARY_COLOR}
@var{params} returns four values: the red, green, blue, and alpha
-secondary color values of the current raster position. Integer values,
+secondary color values of the current raster position. Integer values,
if requested, are linearly mapped from the internal floating-point
representation such that 1.0 returns the most positive representable
integer value, and @r{-1.0} returns the most negative representable
-integer value. The initial value is (1, 1, 1, 1). See
+integer value. The initial value is (1, 1, 1, 1). See
@code{glRasterPos}.
@item @code{GL_CURRENT_RASTER_TEXTURE_COORDS}
@var{params} returns four values: the @var{s}, @var{t}, @var{r}, and
-@var{q} texture coordinates of the current raster position. The initial
-value is (0, 0, 0, 1). See @code{glRasterPos} and
+@var{q} texture coordinates of the current raster position. The initial
+value is (0, 0, 0, 1). See @code{glRasterPos} and
@code{glMultiTexCoord}.
@item @code{GL_CURRENT_SECONDARY_COLOR}
@var{params} returns four values: the red, green, blue, and alpha values
-of the current secondary color. Integer values, if requested, are
+of the current secondary color. Integer values, if requested, are
linearly mapped from the internal floating-point representation such
that 1.0 returns the most positive representable integer value, and
-@r{-1.0} returns the most negative representable integer value. The
-initial value is (0, 0, 0, 0). See @code{glSecondaryColor}.
+@r{-1.0} returns the most negative representable integer value. The
+initial value is (0, 0, 0, 0). See @code{glSecondaryColor}.
@item @code{GL_CURRENT_TEXTURE_COORDS}
@var{params} returns four values: the @var{s}, @var{t}, @var{r}, and
-@var{q} current texture coordinates. The initial value is (0, 0, 0, 1).
+@var{q} current texture coordinates. The initial value is (0, 0, 0, 1).
See @code{glMultiTexCoord}.
@item @code{GL_DEPTH_BIAS}
@var{params} returns one value, the depth bias factor used during pixel
-transfers. The initial value is 0. See @code{glPixelTransfer}.
+transfers. The initial value is 0. See @code{glPixelTransfer}.
@item @code{GL_DEPTH_BITS}
@var{params} returns one value, the value that is used to clear the
-depth buffer. Integer values, if requested, are linearly mapped from the
-internal floating-point representation such that 1.0 returns the most
-positive representable integer value, and @r{-1.0} returns the most
-negative representable integer value. The initial value is 1. See
+depth buffer. Integer values, if requested, are linearly mapped from
+the internal floating-point representation such that 1.0 returns the
+most positive representable integer value, and @r{-1.0} returns the most
+negative representable integer value. The initial value is 1. See
@code{glClearDepth}.
@item @code{GL_DEPTH_FUNC}
@var{params} returns one value, the symbolic constant that indicates the
-depth comparison function. The initial value is @code{GL_LESS}. See
+depth comparison function. The initial value is @code{GL_LESS}. See
@code{glDepthFunc}.
@item @code{GL_DEPTH_RANGE}
@var{params} returns two values: the near and far mapping limits for the
-depth buffer. Integer values, if requested, are linearly mapped from the
-internal floating-point representation such that 1.0 returns the most
-positive representable integer value, and @r{-1.0} returns the most
-negative representable integer value. The initial value is (0, 1). See
+depth buffer. Integer values, if requested, are linearly mapped from
+the internal floating-point representation such that 1.0 returns the
+most positive representable integer value, and @r{-1.0} returns the most
+negative representable integer value. The initial value is (0, 1). See
@code{glDepthRange}.
@item @code{GL_DEPTH_SCALE}
@var{params} returns one value, the depth scale factor used during pixel
-transfers. The initial value is 1. See @code{glPixelTransfer}.
+transfers. The initial value is 1. See @code{glPixelTransfer}.
@item @code{GL_DEPTH_TEST}
@var{params} returns a single boolean value indicating whether depth
-testing of fragments is enabled. The initial value is @code{GL_FALSE}.
+testing of fragments is enabled. The initial value is @code{GL_FALSE}.
See @code{glDepthFunc} and @code{glDepthRange}.
@item @code{GL_DEPTH_WRITEMASK}
@var{params} returns a single boolean value indicating if the depth
-buffer is enabled for writing. The initial value is @code{GL_TRUE}. See
+buffer is enabled for writing. The initial value is @code{GL_TRUE}. See
@code{glDepthMask}.
@item @code{GL_DITHER}
@var{params} returns a single boolean value indicating whether dithering
-of fragment colors and indices is enabled. The initial value is
+of fragment colors and indices is enabled. The initial value is
@code{GL_TRUE}.
@item @code{GL_DOUBLEBUFFER}
@var{params} returns one value, a symbolic constant indicating which
-buffers are being drawn to. See @code{glDrawBuffer}. The initial value
+buffers are being drawn to. See @code{glDrawBuffer}. The initial value
is @code{GL_BACK} if there are back buffers, otherwise it is
@code{GL_FRONT}.
@var{params} returns one value, a symbolic constant indicating which
-buffers are being drawn to by the corresponding output color. See
-@code{glDrawBuffers}. The initial value of @code{GL_DRAW_BUFFER0} is
+buffers are being drawn to by the corresponding output color. See
+@code{glDrawBuffers}. The initial value of @code{GL_DRAW_BUFFER0} is
@code{GL_BACK} if there are back buffers, otherwise it is
-@code{GL_FRONT}. The initial values of draw buffers for all other output
-colors is @code{GL_NONE}.
+@code{GL_FRONT}. The initial values of draw buffers for all other
+output colors is @code{GL_NONE}.
@item @code{GL_EDGE_FLAG}
@var{params} returns a single boolean value indicating whether the
-current edge flag is @code{GL_TRUE} or @code{GL_FALSE}. The initial
-value is @code{GL_TRUE}. See @code{glEdgeFlag}.
+current edge flag is @code{GL_TRUE} or @code{GL_FALSE}. The initial
+value is @code{GL_TRUE}. See @code{glEdgeFlag}.
@item @code{GL_EDGE_FLAG_ARRAY}
@var{params} returns a single boolean value indicating whether the edge
-flag array is enabled. The initial value is @code{GL_FALSE}. See
+flag array is enabled. The initial value is @code{GL_FALSE}. See
@code{glEdgeFlagPointer}.
@item @code{GL_EDGE_FLAG_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the edge flag array. This buffer object would have been
+associated with the edge flag array. This buffer object would have been
bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glEdgeFlagPointer}. If no buffer object was bound
-to this target, 0 is returned. The initial value is 0. See
+recent call to @code{glEdgeFlagPointer}. If no buffer object was bound
+to this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_EDGE_FLAG_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive edge
-flags in the edge flag array. The initial value is 0. See
+flags in the edge flag array. The initial value is 0. See
@code{glEdgeFlagPointer}.
@item @code{GL_ELEMENT_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-currently bound to the target @code{GL_ELEMENT_ARRAY_BUFFER}. If no
-buffer object is bound to this target, 0 is returned. The initial value
-is 0. See @code{glBindBuffer}.
+currently bound to the target @code{GL_ELEMENT_ARRAY_BUFFER}. If no
+buffer object is bound to this target, 0 is returned. The initial value
+is 0. See @code{glBindBuffer}.
@item @code{GL_FEEDBACK_BUFFER_SIZE}
-@var{params} returns one value, the size of the feedback buffer. See
+@var{params} returns one value, the size of the feedback buffer. See
@code{glFeedbackBuffer}.
@item @code{GL_FEEDBACK_BUFFER_TYPE}
-@var{params} returns one value, the type of the feedback buffer. See
+@var{params} returns one value, the type of the feedback buffer. See
@code{glFeedbackBuffer}.
@item @code{GL_FOG}
@var{params} returns a single boolean value indicating whether fogging
-is enabled. The initial value is @code{GL_FALSE}. See @code{glFog}.
+is enabled. The initial value is @code{GL_FALSE}. See @code{glFog}.
@item @code{GL_FOG_COORD_ARRAY}
@var{params} returns a single boolean value indicating whether the fog
-coordinate array is enabled. The initial value is @code{GL_FALSE}. See
+coordinate array is enabled. The initial value is @code{GL_FALSE}. See
@code{glFogCoordPointer}.
@item @code{GL_FOG_COORD_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the fog coordinate array. This buffer object would have
+associated with the fog coordinate array. This buffer object would have
been bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glFogCoordPointer}. If no buffer object was bound
-to this target, 0 is returned. The initial value is 0. See
+recent call to @code{glFogCoordPointer}. If no buffer object was bound
+to this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_FOG_COORD_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive fog
-coordinates in the fog coordinate array. The initial value is 0. See
+coordinates in the fog coordinate array. The initial value is 0. See
@code{glFogCoordPointer}.
@item @code{GL_FOG_COORD_ARRAY_TYPE}
@var{params} returns one value, the type of the fog coordinate array.
-The initial value is @code{GL_FLOAT}. See @code{glFogCoordPointer}.
+The initial value is @code{GL_FLOAT}. See @code{glFogCoordPointer}.
@item @code{GL_FOG_COORD_SRC}
@var{params} returns one value, a symbolic constant indicating the
-source of the fog coordinate. The initial value is
-@code{GL_FRAGMENT_DEPTH}. See @code{glFog}.
+source of the fog coordinate. The initial value is
+@code{GL_FRAGMENT_DEPTH}. See @code{glFog}.
@item @code{GL_FOG_COLOR}
@var{params} returns four values: the red, green, blue, and alpha
-components of the fog color. Integer values, if requested, are linearly
+components of the fog color. Integer values, if requested, are linearly
mapped from the internal floating-point representation such that 1.0
returns the most positive representable integer value, and @r{-1.0}
-returns the most negative representable integer value. The initial value
-is (0, 0, 0, 0). See @code{glFog}.
+returns the most negative representable integer value. The initial
+value is (0, 0, 0, 0). See @code{glFog}.
@item @code{GL_FOG_DENSITY}
-@var{params} returns one value, the fog density parameter. The initial
-value is 1. See @code{glFog}.
+@var{params} returns one value, the fog density parameter. The initial
+value is 1. See @code{glFog}.
@item @code{GL_FOG_END}
@var{params} returns one value, the end factor for the linear fog
-equation. The initial value is 1. See @code{glFog}.
+equation. The initial value is 1. See @code{glFog}.
@item @code{GL_FOG_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the fog hint. The initial value is @code{GL_DONT_CARE}. See
+of the fog hint. The initial value is @code{GL_DONT_CARE}. See
@code{glHint}.
@item @code{GL_FOG_INDEX}
-@var{params} returns one value, the fog color index. The initial value
-is 0. See @code{glFog}.
+@var{params} returns one value, the fog color index. The initial value
+is 0. See @code{glFog}.
@item @code{GL_FOG_MODE}
@var{params} returns one value, a symbolic constant indicating which fog
-equation is selected. The initial value is @code{GL_EXP}. See
+equation is selected. The initial value is @code{GL_EXP}. See
@code{glFog}.
@item @code{GL_FOG_START}
@var{params} returns one value, the start factor for the linear fog
-equation. The initial value is 0. See @code{glFog}.
+equation. The initial value is 0. See @code{glFog}.
@item @code{GL_FRAGMENT_SHADER_DERIVATIVE_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the derivative accuracy hint for fragment shaders. The initial value
-is @code{GL_DONT_CARE}. See @code{glHint}.
+of the derivative accuracy hint for fragment shaders. The initial value
+is @code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_FRONT_FACE}
@var{params} returns one value, a symbolic constant indicating whether
clockwise or counterclockwise polygon winding is treated as
-front-facing. The initial value is @code{GL_CCW}. See
+front-facing. The initial value is @code{GL_CCW}. See
@code{glFrontFace}.
@item @code{GL_GENERATE_MIPMAP_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the mipmap generation filtering hint. The initial value is
-@code{GL_DONT_CARE}. See @code{glHint}.
+of the mipmap generation filtering hint. The initial value is
+@code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_GREEN_BIAS}
@var{params} returns one value, the green bias factor used during pixel
-transfers. The initial value is 0.
+transfers. The initial value is 0.
@item @code{GL_GREEN_BITS}
@var{params} returns one value, the green scale factor used during pixel
-transfers. The initial value is 1. See @code{glPixelTransfer}.
+transfers. The initial value is 1. See @code{glPixelTransfer}.
@item @code{GL_HISTOGRAM}
@var{params} returns a single boolean value indicating whether histogram
-is enabled. The initial value is @code{GL_FALSE}. See
+is enabled. The initial value is @code{GL_FALSE}. See
@code{glHistogram}.
@item @code{GL_INDEX_ARRAY}
@var{params} returns a single boolean value indicating whether the color
-index array is enabled. The initial value is @code{GL_FALSE}. See
+index array is enabled. The initial value is @code{GL_FALSE}. See
@code{glIndexPointer}.
@item @code{GL_INDEX_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the color index array. This buffer object would have
+associated with the color index array. This buffer object would have
been bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glIndexPointer}. If no buffer object was bound to
-this target, 0 is returned. The initial value is 0. See
+recent call to @code{glIndexPointer}. If no buffer object was bound to
+this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_INDEX_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-color indexes in the color index array. The initial value is 0. See
+color indexes in the color index array. The initial value is 0. See
@code{glIndexPointer}.
@item @code{GL_INDEX_ARRAY_TYPE}
@var{params} returns one value, the data type of indexes in the color
-index array. The initial value is @code{GL_FLOAT}. See
+index array. The initial value is @code{GL_FLOAT}. See
@code{glIndexPointer}.
@item @code{GL_INDEX_BITS}
@var{params} returns one value, the color index used to clear the color
-index buffers. The initial value is 0. See @code{glClearIndex}.
+index buffers. The initial value is 0. See @code{glClearIndex}.
@item @code{GL_INDEX_LOGIC_OP}
@var{params} returns a single boolean value indicating whether a
fragment's index values are merged into the framebuffer using a logical
-operation. The initial value is @code{GL_FALSE}. See @code{glLogicOp}.
+operation. The initial value is @code{GL_FALSE}. See @code{glLogicOp}.
@item @code{GL_INDEX_MODE}
@var{params} returns one value, the offset added to color and stencil
-indices during pixel transfers. The initial value is 0. See
+indices during pixel transfers. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_INDEX_SHIFT}
@var{params} returns one value, the amount that color and stencil
-indices are shifted during pixel transfers. The initial value is 0. See
+indices are shifted during pixel transfers. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_INDEX_WRITEMASK}
@var{params} returns one value, a mask indicating which bitplanes of
-each color index buffer can be written. The initial value is all 1's.
+each color index buffer can be written. The initial value is all 1's.
See @code{glIndexMask}.
@item @code{GL_LIGHT}@var{i}
@var{params} returns a single boolean value indicating whether the
-specified light is enabled. The initial value is @code{GL_FALSE}. See
+specified light is enabled. The initial value is @code{GL_FALSE}. See
@code{glLight} and @code{glLightModel}.
@item @code{GL_LIGHTING}
@var{params} returns a single boolean value indicating whether lighting
-is enabled. The initial value is @code{GL_FALSE}. See
+is enabled. The initial value is @code{GL_FALSE}. See
@code{glLightModel}.
@item @code{GL_LIGHT_MODEL_AMBIENT}
@var{params} returns four values: the red, green, blue, and alpha
-components of the ambient intensity of the entire scene. Integer values,
-if requested, are linearly mapped from the internal floating-point
-representation such that 1.0 returns the most positive representable
-integer value, and @r{-1.0} returns the most negative representable
-integer value. The initial value is (0.2, 0.2, 0.2, 1.0). See
-@code{glLightModel}.
+components of the ambient intensity of the entire scene. Integer
+values, if requested, are linearly mapped from the internal
+floating-point representation such that 1.0 returns the most positive
+representable integer value, and @r{-1.0} returns the most negative
+representable integer value. The initial value is (0.2, 0.2, 0.2, 1.0).
+See @code{glLightModel}.
@item @code{GL_LIGHT_MODEL_COLOR_CONTROL}
@var{params} returns a single boolean value indicating whether specular
reflection calculations treat the viewer as being local to the scene.
-The initial value is @code{GL_FALSE}. See @code{glLightModel}.
+The initial value is @code{GL_FALSE}. See @code{glLightModel}.
@item @code{GL_LIGHT_MODEL_TWO_SIDE}
@var{params} returns a single boolean value indicating whether separate
materials are used to compute lighting for front- and back-facing
-polygons. The initial value is @code{GL_FALSE}. See @code{glLightModel}.
+polygons. The initial value is @code{GL_FALSE}. See
+@code{glLightModel}.
@item @code{GL_LINE_SMOOTH}
@var{params} returns a single boolean value indicating whether
-antialiasing of lines is enabled. The initial value is @code{GL_FALSE}.
+antialiasing of lines is enabled. The initial value is @code{GL_FALSE}.
See @code{glLineWidth}.
@item @code{GL_LINE_SMOOTH_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the line antialiasing hint. The initial value is @code{GL_DONT_CARE}.
-See @code{glHint}.
+of the line antialiasing hint. The initial value is
+@code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_LINE_STIPPLE}
@var{params} returns a single boolean value indicating whether stippling
-of lines is enabled. The initial value is @code{GL_FALSE}. See
+of lines is enabled. The initial value is @code{GL_FALSE}. See
@code{glLineStipple}.
@item @code{GL_LINE_STIPPLE_PATTERN}
-@var{params} returns one value, the 16-bit line stipple pattern. The
-initial value is all 1's. See @code{glLineStipple}.
+@var{params} returns one value, the 16-bit line stipple pattern. The
+initial value is all 1's. See @code{glLineStipple}.
@item @code{GL_LINE_STIPPLE_REPEAT}
-@var{params} returns one value, the line stipple repeat factor. The
-initial value is 1. See @code{glLineStipple}.
+@var{params} returns one value, the line stipple repeat factor. The
+initial value is 1. See @code{glLineStipple}.
@item @code{GL_LINE_WIDTH}
@var{params} returns one value, the line width as specified with
-@code{glLineWidth}. The initial value is 1.
+@code{glLineWidth}. The initial value is 1.
@item @code{GL_LINE_WIDTH_GRANULARITY}
@var{params} returns one value, the width difference between adjacent
-supported widths for antialiased lines. See @code{glLineWidth}.
+supported widths for antialiased lines. See @code{glLineWidth}.
@item @code{GL_LINE_WIDTH_RANGE}
@var{params} returns two values: the smallest and largest supported
-widths for antialiased lines. See @code{glLineWidth}.
+widths for antialiased lines. See @code{glLineWidth}.
@item @code{GL_LIST_BASE}
@var{params} returns one value, the base offset added to all names in
-arrays presented to @code{glCallLists}. The initial value is 0. See
+arrays presented to @code{glCallLists}. The initial value is 0. See
@code{glListBase}.
@item @code{GL_LIST_INDEX}
@var{params} returns one value, the name of the display list currently
-under construction. 0 is returned if no display list is currently under
-construction. The initial value is 0. See @code{glNewList}.
+under construction. 0 is returned if no display list is currently under
+construction. The initial value is 0. See @code{glNewList}.
@item @code{GL_LIST_MODE}
@var{params} returns one value, a symbolic constant indicating the
-construction mode of the display list currently under construction. The
-initial value is 0. See @code{glNewList}.
+construction mode of the display list currently under construction. The
+initial value is 0. See @code{glNewList}.
@item @code{GL_LOGIC_OP_MODE}
@var{params} returns one value, a symbolic constant indicating the
-selected logic operation mode. The initial value is @code{GL_COPY}. See
+selected logic operation mode. The initial value is @code{GL_COPY}. See
@code{glLogicOp}.
@item @code{GL_MAP1_COLOR_4}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates colors. The initial value is @code{GL_FALSE}. See
+evaluation generates colors. The initial value is @code{GL_FALSE}. See
@code{glMap1}.
@item @code{GL_MAP1_GRID_DOMAIN}
@var{params} returns two values: the endpoints of the 1D map's grid
-domain. The initial value is (0, 1). See @code{glMapGrid}.
+domain. The initial value is (0, 1). See @code{glMapGrid}.
@item @code{GL_MAP1_GRID_SEGMENTS}
@var{params} returns one value, the number of partitions in the 1D map's
-grid domain. The initial value is 1. See @code{glMapGrid}.
+grid domain. The initial value is 1. See @code{glMapGrid}.
@item @code{GL_MAP1_INDEX}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates color indices. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates color indices. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_NORMAL}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates normals. The initial value is @code{GL_FALSE}. See
+evaluation generates normals. The initial value is @code{GL_FALSE}. See
@code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_1}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 1D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 1D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_2}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 2D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 2D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_3}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 3D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 3D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_TEXTURE_COORD_4}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 4D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 4D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_VERTEX_3}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 3D vertex coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 3D vertex coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP1_VERTEX_4}
@var{params} returns a single boolean value indicating whether 1D
-evaluation generates 4D vertex coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap1}.
+evaluation generates 4D vertex coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap1}.
@item @code{GL_MAP2_COLOR_4}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates colors. The initial value is @code{GL_FALSE}. See
+evaluation generates colors. The initial value is @code{GL_FALSE}. See
@code{glMap2}.
@item @code{GL_MAP2_GRID_DOMAIN}
@var{params} returns four values: the endpoints of the 2D map's
-@r{@var{i}} and @r{@var{j}} grid domains. The initial value is (0,1;
-0,1). See @code{glMapGrid}.
+@r{@var{i}} and @r{@var{j}} grid domains. The initial value is (0,1;
+0,1). See @code{glMapGrid}.
@item @code{GL_MAP2_GRID_SEGMENTS}
@var{params} returns two values: the number of partitions in the 2D
-map's @r{@var{i}} and @r{@var{j}} grid domains. The initial value is
-(1,1). See @code{glMapGrid}.
+map's @r{@var{i}} and @r{@var{j}} grid domains. The initial value is
+(1,1). See @code{glMapGrid}.
@item @code{GL_MAP2_INDEX}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates color indices. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates color indices. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_NORMAL}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates normals. The initial value is @code{GL_FALSE}. See
+evaluation generates normals. The initial value is @code{GL_FALSE}. See
@code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_1}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 1D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 1D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_2}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 2D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 2D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_3}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 3D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 3D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_TEXTURE_COORD_4}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 4D texture coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 4D texture coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_VERTEX_3}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 3D vertex coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 3D vertex coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP2_VERTEX_4}
@var{params} returns a single boolean value indicating whether 2D
-evaluation generates 4D vertex coordinates. The initial value is
-@code{GL_FALSE}. See @code{glMap2}.
+evaluation generates 4D vertex coordinates. The initial value is
+@code{GL_FALSE}. See @code{glMap2}.
@item @code{GL_MAP_COLOR}
@var{params} returns a single boolean value indicating if colors and
color indices are to be replaced by table lookup during pixel transfers.
-The initial value is @code{GL_FALSE}. See @code{glPixelTransfer}.
+The initial value is @code{GL_FALSE}. See @code{glPixelTransfer}.
@item @code{GL_MAP_STENCIL}
@var{params} returns a single boolean value indicating if stencil
-indices are to be replaced by table lookup during pixel transfers. The
-initial value is @code{GL_FALSE}. See @code{glPixelTransfer}.
+indices are to be replaced by table lookup during pixel transfers. The
+initial value is @code{GL_FALSE}. See @code{glPixelTransfer}.
@item @code{GL_MATRIX_MODE}
@var{params} returns one value, a symbolic constant indicating which
-matrix stack is currently the target of all matrix operations. The
-initial value is @code{GL_MODELVIEW}. See @code{glMatrixMode}.
+matrix stack is currently the target of all matrix operations. The
+initial value is @code{GL_MODELVIEW}. See @code{glMatrixMode}.
@item @code{GL_MAX_3D_TEXTURE_SIZE}
@var{params} returns one value, a rough estimate of the largest 3D
-texture that the GL can handle. The value must be at least 16. If the GL
-version is 1.2 or greater, use @code{GL_PROXY_TEXTURE_3D} to determine
-if a texture is too large. See @code{glTexImage3D}.
+texture that the GL can handle. The value must be at least 16. If the
+GL version is 1.2 or greater, use @code{GL_PROXY_TEXTURE_3D} to
+determine if a texture is too large. See @code{glTexImage3D}.
@item @code{GL_MAX_CLIENT_ATTRIB_STACK_DEPTH}
@var{params} returns one value indicating the maximum supported depth of
-the client attribute stack. See @code{glPushClientAttrib}.
+the client attribute stack. See @code{glPushClientAttrib}.
@item @code{GL_MAX_ATTRIB_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-attribute stack. The value must be at least 16. See @code{glPushAttrib}.
+attribute stack. The value must be at least 16. See
+@code{glPushAttrib}.
@item @code{GL_MAX_CLIP_PLANES}
@var{params} returns one value, the maximum number of
-application-defined clipping planes. The value must be at least 6. See
+application-defined clipping planes. The value must be at least 6. See
@code{glClipPlane}.
@item @code{GL_MAX_COLOR_MATRIX_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the color
-matrix stack. The value must be at least 2. See @code{glPushMatrix}.
+matrix stack. The value must be at least 2. See @code{glPushMatrix}.
@item @code{GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS}
@var{params} returns one value, the maximum supported texture image
units that can be used to access texture maps from the vertex shader and
-the fragment processor combined. If both the vertex shader and the
+the fragment processor combined. If both the vertex shader and the
fragment processing stage access the same texture image unit, then that
-counts as using two texture image units against this limit. The value
-must be at least 2. See @code{glActiveTexture}.
+counts as using two texture image units against this limit. The value
+must be at least 2. See @code{glActiveTexture}.
@item @code{GL_MAX_CUBE_MAP_TEXTURE_SIZE}
-@var{params} returns one value. The value gives a rough estimate of the
-largest cube-map texture that the GL can handle. The value must be at
-least 16. If the GL version is 1.3 or greater, use
+@var{params} returns one value. The value gives a rough estimate of the
+largest cube-map texture that the GL can handle. The value must be at
+least 16. If the GL version is 1.3 or greater, use
@code{GL_PROXY_TEXTURE_CUBE_MAP} to determine if a texture is too large.
See @code{glTexImage2D}.
@var{params} returns one value, the maximum number of simultaneous
output colors allowed from a fragment shader using the
-@code{gl_FragData} built-in array. The value must be at least 1. See
+@code{gl_FragData} built-in array. The value must be at least 1. See
@code{glDrawBuffers}.
@item @code{GL_MAX_ELEMENTS_INDICES}
@var{params} returns one value, the recommended maximum number of vertex
-array indices. See @code{glDrawRangeElements}.
+array indices. See @code{glDrawRangeElements}.
@item @code{GL_MAX_ELEMENTS_VERTICES}
@var{params} returns one value, the recommended maximum number of vertex
-array vertices. See @code{glDrawRangeElements}.
+array vertices. See @code{glDrawRangeElements}.
@item @code{GL_MAX_EVAL_ORDER}
@var{params} returns one value, the maximum equation order supported by
-1D and 2D evaluators. The value must be at least 8. See @code{glMap1}
+1D and 2D evaluators. The value must be at least 8. See @code{glMap1}
and @code{glMap2}.
@item @code{GL_MAX_FRAGMENT_UNIFORM_COMPONENTS}
@var{params} returns one value, the maximum number of individual
floating-point, integer, or boolean values that can be held in uniform
-variable storage for a fragment shader. The value must be at least 64.
+variable storage for a fragment shader. The value must be at least 64.
See @code{glUniform}.
@item @code{GL_MAX_LIGHTS}
-@var{params} returns one value, the maximum number of lights. The value
-must be at least 8. See @code{glLight}.
+@var{params} returns one value, the maximum number of lights. The value
+must be at least 8. See @code{glLight}.
@item @code{GL_MAX_LIST_NESTING}
@var{params} returns one value, the maximum recursion depth allowed
-during display-list traversal. The value must be at least 64. See
+during display-list traversal. The value must be at least 64. See
@code{glCallList}.
@item @code{GL_MAX_MODELVIEW_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-modelview matrix stack. The value must be at least 32. See
+modelview matrix stack. The value must be at least 32. See
@code{glPushMatrix}.
@item @code{GL_MAX_NAME_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-selection name stack. The value must be at least 64. See
+selection name stack. The value must be at least 64. See
@code{glPushName}.
@item @code{GL_MAX_PIXEL_MAP_TABLE}
@var{params} returns one value, the maximum supported size of a
-@code{glPixelMap} lookup table. The value must be at least 32. See
+@code{glPixelMap} lookup table. The value must be at least 32. See
@code{glPixelMap}.
@item @code{GL_MAX_PROJECTION_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-projection matrix stack. The value must be at least 2. See
+projection matrix stack. The value must be at least 2. See
@code{glPushMatrix}.
@item @code{GL_MAX_TEXTURE_COORDS}
@var{params} returns one value, the maximum number of texture coordinate
-sets available to vertex and fragment shaders. The value must be at
-least 2. See @code{glActiveTexture} and @code{glClientActiveTexture}.
+sets available to vertex and fragment shaders. The value must be at
+least 2. See @code{glActiveTexture} and @code{glClientActiveTexture}.
@item @code{GL_MAX_TEXTURE_IMAGE_UNITS}
@var{params} returns one value, the maximum supported texture image
units that can be used to access texture maps from the fragment shader.
-The value must be at least 2. See @code{glActiveTexture}.
+The value must be at least 2. See @code{glActiveTexture}.
@item @code{GL_MAX_TEXTURE_LOD_BIAS}
@var{params} returns one value, the maximum, absolute value of the
-texture level-of-detail bias. The value must be at least 4.
+texture level-of-detail bias. The value must be at least 4.
@item @code{GL_MAX_TEXTURE_SIZE}
-@var{params} returns one value. The value gives a rough estimate of the
-largest texture that the GL can handle. The value must be at least 64.
+@var{params} returns one value. The value gives a rough estimate of the
+largest texture that the GL can handle. The value must be at least 64.
If the GL version is 1.1 or greater, use @code{GL_PROXY_TEXTURE_1D} or
-@code{GL_PROXY_TEXTURE_2D} to determine if a texture is too large. See
+@code{GL_PROXY_TEXTURE_2D} to determine if a texture is too large. See
@code{glTexImage1D} and @code{glTexImage2D}.
@item @code{GL_MAX_TEXTURE_STACK_DEPTH}
@var{params} returns one value, the maximum supported depth of the
-texture matrix stack. The value must be at least 2. See
+texture matrix stack. The value must be at least 2. See
@code{glPushMatrix}.
@item @code{GL_MAX_TEXTURE_UNITS}
@var{params} returns a single value indicating the number of
-conventional texture units supported. Each conventional texture unit
+conventional texture units supported. Each conventional texture unit
includes both a texture coordinate set and a texture image unit.
Conventional texture units may be used for fixed-function (non-shader)
-rendering. The value must be at least 2. Additional texture coordinate
+rendering. The value must be at least 2. Additional texture coordinate
sets and texture image units may be accessed from vertex and fragment
-shaders. See @code{glActiveTexture} and @code{glClientActiveTexture}.
+shaders. See @code{glActiveTexture} and @code{glClientActiveTexture}.
@item @code{GL_MAX_VARYING_FLOATS}
@var{params} returns one value, the maximum number of interpolators
available for processing varying variables used by vertex and fragment
-shaders. This value represents the number of individual floating-point
+shaders. This value represents the number of individual floating-point
values that can be interpolated; varying variables declared as vectors,
-matrices, and arrays will all consume multiple interpolators. The value
+matrices, and arrays will all consume multiple interpolators. The value
must be at least 32.
@item @code{GL_MAX_VERTEX_ATTRIBS}
@var{params} returns one value, the maximum number of 4-component
-generic vertex attributes accessible to a vertex shader. The value must
-be at least 16. See @code{glVertexAttrib}.
+generic vertex attributes accessible to a vertex shader. The value must
+be at least 16. See @code{glVertexAttrib}.
@item @code{GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS}
@var{params} returns one value, the maximum supported texture image
units that can be used to access texture maps from the vertex shader.
-The value may be 0. See @code{glActiveTexture}.
+The value may be 0. See @code{glActiveTexture}.
@item @code{GL_MAX_VERTEX_UNIFORM_COMPONENTS}
@var{params} returns one value, the maximum number of individual
floating-point, integer, or boolean values that can be held in uniform
-variable storage for a vertex shader. The value must be at least 512.
+variable storage for a vertex shader. The value must be at least 512.
See @code{glUniform}.
@item @code{GL_MAX_VIEWPORT_DIMS}
@var{params} returns two values: the maximum supported width and height
-of the viewport. These must be at least as large as the visible
-dimensions of the display being rendered to. See @code{glViewport}.
+of the viewport. These must be at least as large as the visible
+dimensions of the display being rendered to. See @code{glViewport}.
@item @code{GL_MINMAX}
@var{params} returns a single boolean value indicating whether pixel
-minmax values are computed. The initial value is @code{GL_FALSE}. See
+minmax values are computed. The initial value is @code{GL_FALSE}. See
@code{glMinmax}.
@item @code{GL_MODELVIEW_MATRIX}
@var{params} returns sixteen values: the modelview matrix on the top of
-the modelview matrix stack. Initially this matrix is the identity
-matrix. See @code{glPushMatrix}.
+the modelview matrix stack. Initially this matrix is the identity
+matrix. See @code{glPushMatrix}.
@item @code{GL_MODELVIEW_STACK_DEPTH}
@var{params} returns one value, the number of matrices on the modelview
-matrix stack. The initial value is 1. See @code{glPushMatrix}.
+matrix stack. The initial value is 1. See @code{glPushMatrix}.
@item @code{GL_NAME_STACK_DEPTH}
@var{params} returns one value, the number of names on the selection
-name stack. The initial value is 0. See @code{glPushName}.
+name stack. The initial value is 0. See @code{glPushName}.
@item @code{GL_NORMAL_ARRAY}
@var{params} returns a single boolean value, indicating whether the
-normal array is enabled. The initial value is @code{GL_FALSE}. See
+normal array is enabled. The initial value is @code{GL_FALSE}. See
@code{glNormalPointer}.
@item @code{GL_NORMAL_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the normal array. This buffer object would have been
+associated with the normal array. This buffer object would have been
bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glNormalPointer}. If no buffer object was bound to
-this target, 0 is returned. The initial value is 0. See
+recent call to @code{glNormalPointer}. If no buffer object was bound to
+this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_NORMAL_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-normals in the normal array. The initial value is 0. See
+normals in the normal array. The initial value is 0. See
@code{glNormalPointer}.
@item @code{GL_NORMAL_ARRAY_TYPE}
@var{params} returns one value, the data type of each coordinate in the
-normal array. The initial value is @code{GL_FLOAT}. See
+normal array. The initial value is @code{GL_FLOAT}. See
@code{glNormalPointer}.
@item @code{GL_NORMALIZE}
@var{params} returns a single boolean value indicating whether normals
are automatically scaled to unit length after they have been transformed
-to eye coordinates. The initial value is @code{GL_FALSE}. See
+to eye coordinates. The initial value is @code{GL_FALSE}. See
@code{glNormal}.
@item @code{GL_NUM_COMPRESSED_TEXTURE_FORMATS}
@var{params} returns a single integer value indicating the number of
-available compressed texture formats. The minimum value is 0. See
+available compressed texture formats. The minimum value is 0. See
@code{glCompressedTexImage2D}.
@item @code{GL_PACK_ALIGNMENT}
@var{params} returns one value, the byte alignment used for writing
-pixel data to memory. The initial value is 4. See @code{glPixelStore}.
+pixel data to memory. The initial value is 4. See @code{glPixelStore}.
@item @code{GL_PACK_IMAGE_HEIGHT}
@var{params} returns one value, the image height used for writing pixel
-data to memory. The initial value is 0. See @code{glPixelStore}.
+data to memory. The initial value is 0. See @code{glPixelStore}.
@item @code{GL_PACK_LSB_FIRST}
@var{params} returns a single boolean value indicating whether
single-bit pixels being written to memory are written first to the least
-significant bit of each unsigned byte. The initial value is
-@code{GL_FALSE}. See @code{glPixelStore}.
+significant bit of each unsigned byte. The initial value is
+@code{GL_FALSE}. See @code{glPixelStore}.
@item @code{GL_PACK_ROW_LENGTH}
@var{params} returns one value, the row length used for writing pixel
-data to memory. The initial value is 0. See @code{glPixelStore}.
+data to memory. The initial value is 0. See @code{glPixelStore}.
@item @code{GL_PACK_SKIP_IMAGES}
@var{params} returns one value, the number of pixel images skipped
-before the first pixel is written into memory. The initial value is 0.
+before the first pixel is written into memory. The initial value is 0.
See @code{glPixelStore}.
@item @code{GL_PACK_SKIP_PIXELS}
@var{params} returns one value, the number of pixel locations skipped
-before the first pixel is written into memory. The initial value is 0.
+before the first pixel is written into memory. The initial value is 0.
See @code{glPixelStore}.
@item @code{GL_PACK_SKIP_ROWS}
@var{params} returns one value, the number of rows of pixel locations
-skipped before the first pixel is written into memory. The initial value
-is 0. See @code{glPixelStore}.
+skipped before the first pixel is written into memory. The initial
+value is 0. See @code{glPixelStore}.
@item @code{GL_PACK_SWAP_BYTES}
@var{params} returns a single boolean value indicating whether the bytes
of two-byte and four-byte pixel indices and components are swapped
-before being written to memory. The initial value is @code{GL_FALSE}.
+before being written to memory. The initial value is @code{GL_FALSE}.
See @code{glPixelStore}.
@item @code{GL_PERSPECTIVE_CORRECTION_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the perspective correction hint. The initial value is
-@code{GL_DONT_CARE}. See @code{glHint}.
+of the perspective correction hint. The initial value is
+@code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_PIXEL_MAP_A_TO_A_SIZE}
@var{params} returns one value, the size of the alpha-to-alpha pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_B_TO_B_SIZE}
@var{params} returns one value, the size of the blue-to-blue pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_G_TO_G_SIZE}
@var{params} returns one value, the size of the green-to-green pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_I_TO_A_SIZE}
@var{params} returns one value, the size of the index-to-alpha pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_I_TO_B_SIZE}
@var{params} returns one value, the size of the index-to-blue pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_I_TO_G_SIZE}
@var{params} returns one value, the size of the index-to-green pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_I_TO_I_SIZE}
@var{params} returns one value, the size of the index-to-index pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_I_TO_R_SIZE}
@var{params} returns one value, the size of the index-to-red pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_R_TO_R_SIZE}
@var{params} returns one value, the size of the red-to-red pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_MAP_S_TO_S_SIZE}
@var{params} returns one value, the size of the stencil-to-stencil pixel
-translation table. The initial value is 1. See @code{glPixelMap}.
+translation table. The initial value is 1. See @code{glPixelMap}.
@item @code{GL_PIXEL_PACK_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-currently bound to the target @code{GL_PIXEL_PACK_BUFFER}. If no buffer
-object is bound to this target, 0 is returned. The initial value is 0.
+currently bound to the target @code{GL_PIXEL_PACK_BUFFER}. If no buffer
+object is bound to this target, 0 is returned. The initial value is 0.
See @code{glBindBuffer}.
@item @code{GL_PIXEL_UNPACK_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-currently bound to the target @code{GL_PIXEL_UNPACK_BUFFER}. If no
-buffer object is bound to this target, 0 is returned. The initial value
-is 0. See @code{glBindBuffer}.
+currently bound to the target @code{GL_PIXEL_UNPACK_BUFFER}. If no
+buffer object is bound to this target, 0 is returned. The initial value
+is 0. See @code{glBindBuffer}.
@item @code{GL_POINT_DISTANCE_ATTENUATION}
@var{params} returns three values, the coefficients for computing the
-attenuation value for points. See @code{glPointParameter}.
+attenuation value for points. See @code{glPointParameter}.
@item @code{GL_POINT_FADE_THRESHOLD_SIZE}
@var{params} returns one value, the point size threshold for determining
-the point size. See @code{glPointParameter}.
+the point size. See @code{glPointParameter}.
@item @code{GL_POINT_SIZE}
@var{params} returns one value, the point size as specified by
-@code{glPointSize}. The initial value is 1.
+@code{glPointSize}. The initial value is 1.
@item @code{GL_POINT_SIZE_GRANULARITY}
@var{params} returns one value, the size difference between adjacent
-supported sizes for antialiased points. See @code{glPointSize}.
+supported sizes for antialiased points. See @code{glPointSize}.
@item @code{GL_POINT_SIZE_MAX}
@var{params} returns one value, the upper bound for the attenuated point
-sizes. The initial value is 0.0. See @code{glPointParameter}.
+sizes. The initial value is 0.0. See @code{glPointParameter}.
@item @code{GL_POINT_SIZE_MIN}
@var{params} returns one value, the lower bound for the attenuated point
-sizes. The initial value is 1.0. See @code{glPointParameter}.
+sizes. The initial value is 1.0. See @code{glPointParameter}.
@item @code{GL_POINT_SIZE_RANGE}
@var{params} returns two values: the smallest and largest supported
-sizes for antialiased points. The smallest size must be at most 1, and
-the largest size must be at least 1. See @code{glPointSize}.
+sizes for antialiased points. The smallest size must be at most 1, and
+the largest size must be at least 1. See @code{glPointSize}.
@item @code{GL_POINT_SMOOTH}
@var{params} returns a single boolean value indicating whether
-antialiasing of points is enabled. The initial value is @code{GL_FALSE}.
-See @code{glPointSize}.
+antialiasing of points is enabled. The initial value is
+@code{GL_FALSE}. See @code{glPointSize}.
@item @code{GL_POINT_SMOOTH_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the point antialiasing hint. The initial value is
-@code{GL_DONT_CARE}. See @code{glHint}.
+of the point antialiasing hint. The initial value is
+@code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_POINT_SPRITE}
@var{params} returns a single boolean value indicating whether point
-sprite is enabled. The initial value is @code{GL_FALSE}.
+sprite is enabled. The initial value is @code{GL_FALSE}.
@item @code{GL_POLYGON_MODE}
@var{params} returns two values: symbolic constants indicating whether
front-facing and back-facing polygons are rasterized as points, lines,
-or filled polygons. The initial value is @code{GL_FILL}. See
+or filled polygons. The initial value is @code{GL_FILL}. See
@code{glPolygonMode}.
@item @code{GL_POLYGON_OFFSET_FACTOR}
@var{params} returns one value, the scaling factor used to determine the
variable offset that is added to the depth value of each fragment
-generated when a polygon is rasterized. The initial value is 0. See
+generated when a polygon is rasterized. The initial value is 0. See
@code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_UNITS}
-@var{params} returns one value. This value is multiplied by an
+@var{params} returns one value. This value is multiplied by an
implementation-specific value and then added to the depth value of each
-fragment generated when a polygon is rasterized. The initial value is 0.
-See @code{glPolygonOffset}.
+fragment generated when a polygon is rasterized. The initial value is
+0. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_FILL}
@var{params} returns a single boolean value indicating whether polygon
-offset is enabled for polygons in fill mode. The initial value is
-@code{GL_FALSE}. See @code{glPolygonOffset}.
+offset is enabled for polygons in fill mode. The initial value is
+@code{GL_FALSE}. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_LINE}
@var{params} returns a single boolean value indicating whether polygon
-offset is enabled for polygons in line mode. The initial value is
-@code{GL_FALSE}. See @code{glPolygonOffset}.
+offset is enabled for polygons in line mode. The initial value is
+@code{GL_FALSE}. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_OFFSET_POINT}
@var{params} returns a single boolean value indicating whether polygon
-offset is enabled for polygons in point mode. The initial value is
-@code{GL_FALSE}. See @code{glPolygonOffset}.
+offset is enabled for polygons in point mode. The initial value is
+@code{GL_FALSE}. See @code{glPolygonOffset}.
@item @code{GL_POLYGON_SMOOTH}
@var{params} returns a single boolean value indicating whether
-antialiasing of polygons is enabled. The initial value is
-@code{GL_FALSE}. See @code{glPolygonMode}.
+antialiasing of polygons is enabled. The initial value is
+@code{GL_FALSE}. See @code{glPolygonMode}.
@item @code{GL_POLYGON_SMOOTH_HINT}
@var{params} returns one value, a symbolic constant indicating the mode
-of the polygon antialiasing hint. The initial value is
-@code{GL_DONT_CARE}. See @code{glHint}.
+of the polygon antialiasing hint. The initial value is
+@code{GL_DONT_CARE}. See @code{glHint}.
@item @code{GL_POLYGON_STIPPLE}
@var{params} returns a single boolean value indicating whether polygon
-stippling is enabled. The initial value is @code{GL_FALSE}. See
+stippling is enabled. The initial value is @code{GL_FALSE}. See
@code{glPolygonStipple}.
@item @code{GL_POST_COLOR_MATRIX_COLOR_TABLE}
@var{params} returns a single boolean value indicating whether post
-color matrix transformation lookup is enabled. The initial value is
-@code{GL_FALSE}. See @code{glColorTable}.
+color matrix transformation lookup is enabled. The initial value is
+@code{GL_FALSE}. See @code{glColorTable}.
@item @code{GL_POST_COLOR_MATRIX_RED_BIAS}
@var{params} returns one value, the red bias factor applied to RGBA
-fragments after color matrix transformations. The initial value is 0.
+fragments after color matrix transformations. The initial value is 0.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_GREEN_BIAS}
@var{params} returns one value, the green bias factor applied to RGBA
-fragments after color matrix transformations. The initial value is 0.
+fragments after color matrix transformations. The initial value is 0.
See @code{glPixelTransfer}
@item @code{GL_POST_COLOR_MATRIX_BLUE_BIAS}
@var{params} returns one value, the blue bias factor applied to RGBA
-fragments after color matrix transformations. The initial value is 0.
+fragments after color matrix transformations. The initial value is 0.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_ALPHA_BIAS}
@var{params} returns one value, the alpha bias factor applied to RGBA
-fragments after color matrix transformations. The initial value is 0.
+fragments after color matrix transformations. The initial value is 0.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_RED_SCALE}
@var{params} returns one value, the red scale factor applied to RGBA
-fragments after color matrix transformations. The initial value is 1.
+fragments after color matrix transformations. The initial value is 1.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_GREEN_SCALE}
@var{params} returns one value, the green scale factor applied to RGBA
-fragments after color matrix transformations. The initial value is 1.
+fragments after color matrix transformations. The initial value is 1.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_BLUE_SCALE}
@var{params} returns one value, the blue scale factor applied to RGBA
-fragments after color matrix transformations. The initial value is 1.
+fragments after color matrix transformations. The initial value is 1.
See @code{glPixelTransfer}.
@item @code{GL_POST_COLOR_MATRIX_ALPHA_SCALE}
@var{params} returns one value, the alpha scale factor applied to RGBA
-fragments after color matrix transformations. The initial value is 1.
+fragments after color matrix transformations. The initial value is 1.
See @code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_COLOR_TABLE}
@var{params} returns a single boolean value indicating whether post
-convolution lookup is enabled. The initial value is @code{GL_FALSE}. See
-@code{glColorTable}.
+convolution lookup is enabled. The initial value is @code{GL_FALSE}.
+See @code{glColorTable}.
@item @code{GL_POST_CONVOLUTION_RED_BIAS}
@var{params} returns one value, the red bias factor applied to RGBA
-fragments after convolution. The initial value is 0. See
+fragments after convolution. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_GREEN_BIAS}
@var{params} returns one value, the green bias factor applied to RGBA
-fragments after convolution. The initial value is 0. See
+fragments after convolution. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_BLUE_BIAS}
@var{params} returns one value, the blue bias factor applied to RGBA
-fragments after convolution. The initial value is 0. See
+fragments after convolution. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_ALPHA_BIAS}
@var{params} returns one value, the alpha bias factor applied to RGBA
-fragments after convolution. The initial value is 0. See
+fragments after convolution. The initial value is 0. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_RED_SCALE}
@var{params} returns one value, the red scale factor applied to RGBA
-fragments after convolution. The initial value is 1. See
+fragments after convolution. The initial value is 1. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_GREEN_SCALE}
@var{params} returns one value, the green scale factor applied to RGBA
-fragments after convolution. The initial value is 1. See
+fragments after convolution. The initial value is 1. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_BLUE_SCALE}
@var{params} returns one value, the blue scale factor applied to RGBA
-fragments after convolution. The initial value is 1. See
+fragments after convolution. The initial value is 1. See
@code{glPixelTransfer}.
@item @code{GL_POST_CONVOLUTION_ALPHA_SCALE}
@var{params} returns one value, the alpha scale factor applied to RGBA
-fragments after convolution. The initial value is 1. See
+fragments after convolution. The initial value is 1. See
@code{glPixelTransfer}.
@item @code{GL_PROJECTION_MATRIX}
@var{params} returns sixteen values: the projection matrix on the top of
-the projection matrix stack. Initially this matrix is the identity
-matrix. See @code{glPushMatrix}.
+the projection matrix stack. Initially this matrix is the identity
+matrix. See @code{glPushMatrix}.
@item @code{GL_PROJECTION_STACK_DEPTH}
@var{params} returns one value, the number of matrices on the projection
-matrix stack. The initial value is 1. See @code{glPushMatrix}.
+matrix stack. The initial value is 1. See @code{glPushMatrix}.
@item @code{GL_READ_BUFFER}
@var{params} returns one value, a symbolic constant indicating which
-color buffer is selected for reading. The initial value is
+color buffer is selected for reading. The initial value is
@code{GL_BACK} if there is a back buffer, otherwise it is
-@code{GL_FRONT}. See @code{glReadPixels} and @code{glAccum}.
+@code{GL_FRONT}. See @code{glReadPixels} and @code{glAccum}.
@item @code{GL_RED_BIAS}
@var{params} returns one value, the red bias factor used during pixel
-transfers. The initial value is 0.
+transfers. The initial value is 0.
@item @code{GL_RED_BITS}
@var{params} returns one value, the red scale factor used during pixel
-transfers. The initial value is 1. See @code{glPixelTransfer}.
+transfers. The initial value is 1. See @code{glPixelTransfer}.
@item @code{GL_RENDER_MODE}
@var{params} returns one value, a symbolic constant indicating whether
-the GL is in render, select, or feedback mode. The initial value is
-@code{GL_RENDER}. See @code{glRenderMode}.
+the GL is in render, select, or feedback mode. The initial value is
+@code{GL_RENDER}. See @code{glRenderMode}.
@item @code{GL_RESCALE_NORMAL}
@var{params} returns single boolean value indicating whether normal
-rescaling is enabled. See @code{glEnable}.
+rescaling is enabled. See @code{glEnable}.
@item @code{GL_RGBA_MODE}
@var{params} returns a single boolean value indicating whether the GL is
-in RGBA mode (true) or color index mode (false). See @code{glColor}.
+in RGBA mode (true) or color index mode (false). See @code{glColor}.
@item @code{GL_SAMPLE_BUFFERS}
@var{params} returns a single integer value indicating the number of
-sample buffers associated with the framebuffer. See
+sample buffers associated with the framebuffer. See
@code{glSampleCoverage}.
@item @code{GL_SAMPLE_COVERAGE_VALUE}
@var{params} returns a single positive floating-point value indicating
-the current sample coverage value. See @code{glSampleCoverage}.
+the current sample coverage value. See @code{glSampleCoverage}.
@item @code{GL_SAMPLE_COVERAGE_INVERT}
@var{params} returns a single boolean value indicating if the temporary
-coverage value should be inverted. See @code{glSampleCoverage}.
+coverage value should be inverted. See @code{glSampleCoverage}.
@item @code{GL_SAMPLES}
@var{params} returns a single integer value indicating the coverage mask
-size. See @code{glSampleCoverage}.
+size. See @code{glSampleCoverage}.
@item @code{GL_SCISSOR_BOX}
@var{params} returns four values: the @r{@var{x}} and @r{@var{y}} window
coordinates of the scissor box, followed by its width and height.
Initially the @r{@var{x}} and @r{@var{y}} window coordinates are both 0
-and the width and height are set to the size of the window. See
+and the width and height are set to the size of the window. See
@code{glScissor}.
@item @code{GL_SCISSOR_TEST}
@var{params} returns a single boolean value indicating whether
-scissoring is enabled. The initial value is @code{GL_FALSE}. See
+scissoring is enabled. The initial value is @code{GL_FALSE}. See
@code{glScissor}.
@item @code{GL_SECONDARY_COLOR_ARRAY}
@var{params} returns a single boolean value indicating whether the
-secondary color array is enabled. The initial value is @code{GL_FALSE}.
+secondary color array is enabled. The initial value is @code{GL_FALSE}.
See @code{glSecondaryColorPointer}.
@item @code{GL_SECONDARY_COLOR_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the secondary color array. This buffer object would have
-been bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glSecondaryColorPointer}. If no buffer object was
-bound to this target, 0 is returned. The initial value is 0. See
+associated with the secondary color array. This buffer object would
+have been bound to the target @code{GL_ARRAY_BUFFER} at the time of the
+most recent call to @code{glSecondaryColorPointer}. If no buffer object
+was bound to this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_SECONDARY_COLOR_ARRAY_SIZE}
@var{params} returns one value, the number of components per color in
-the secondary color array. The initial value is 3. See
+the secondary color array. The initial value is 3. See
@code{glSecondaryColorPointer}.
@item @code{GL_SECONDARY_COLOR_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-colors in the secondary color array. The initial value is 0. See
+colors in the secondary color array. The initial value is 0. See
@code{glSecondaryColorPointer}.
@item @code{GL_SECONDARY_COLOR_ARRAY_TYPE}
@var{params} returns one value, the data type of each component in the
-secondary color array. The initial value is @code{GL_FLOAT}. See
+secondary color array. The initial value is @code{GL_FLOAT}. See
@code{glSecondaryColorPointer}.
@item @code{GL_SELECTION_BUFFER_SIZE}
-@var{params} return one value, the size of the selection buffer. See
+@var{params} return one value, the size of the selection buffer. See
@code{glSelectBuffer}.
@item @code{GL_SEPARABLE_2D}
@var{params} returns a single boolean value indicating whether 2D
-separable convolution is enabled. The initial value is @code{GL_FALSE}.
+separable convolution is enabled. The initial value is @code{GL_FALSE}.
See @code{glSeparableFilter2D}.
@item @code{GL_SHADE_MODEL}
@var{params} returns one value, a symbolic constant indicating whether
-the shading mode is flat or smooth. The initial value is
-@code{GL_SMOOTH}. See @code{glShadeModel}.
+the shading mode is flat or smooth. The initial value is
+@code{GL_SMOOTH}. See @code{glShadeModel}.
@item @code{GL_SMOOTH_LINE_WIDTH_RANGE}
@var{params} returns two values, the smallest and largest supported
-widths for antialiased lines. See @code{glLineWidth}.
+widths for antialiased lines. See @code{glLineWidth}.
@item @code{GL_SMOOTH_LINE_WIDTH_GRANULARITY}
@var{params} returns one value, the granularity of widths for
-antialiased lines. See @code{glLineWidth}.
+antialiased lines. See @code{glLineWidth}.
@item @code{GL_SMOOTH_POINT_SIZE_RANGE}
@var{params} returns two values, the smallest and largest supported
-widths for antialiased points. See @code{glPointSize}.
+widths for antialiased points. See @code{glPointSize}.
@item @code{GL_SMOOTH_POINT_SIZE_GRANULARITY}
@var{params} returns one value, the granularity of sizes for antialiased
-points. See @code{glPointSize}.
+points. See @code{glPointSize}.
@item @code{GL_STENCIL_BACK_FAIL}
@var{params} returns one value, a symbolic constant indicating what
action is taken for back-facing polygons when the stencil test fails.
-The initial value is @code{GL_KEEP}. See @code{glStencilOpSeparate}.
+The initial value is @code{GL_KEEP}. See @code{glStencilOpSeparate}.
@item @code{GL_STENCIL_BACK_FUNC}
@var{params} returns one value, a symbolic constant indicating what
function is used for back-facing polygons to compare the stencil
-reference value with the stencil buffer value. The initial value is
-@code{GL_ALWAYS}. See @code{glStencilFuncSeparate}.
+reference value with the stencil buffer value. The initial value is
+@code{GL_ALWAYS}. See @code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_BACK_PASS_DEPTH_FAIL}
@var{params} returns one value, a symbolic constant indicating what
action is taken for back-facing polygons when the stencil test passes,
-but the depth test fails. The initial value is @code{GL_KEEP}. See
+but the depth test fails. The initial value is @code{GL_KEEP}. See
@code{glStencilOpSeparate}.
@item @code{GL_STENCIL_BACK_PASS_DEPTH_PASS}
@var{params} returns one value, a symbolic constant indicating what
action is taken for back-facing polygons when the stencil test passes
-and the depth test passes. The initial value is @code{GL_KEEP}. See
+and the depth test passes. The initial value is @code{GL_KEEP}. See
@code{glStencilOpSeparate}.
@item @code{GL_STENCIL_BACK_REF}
@var{params} returns one value, the reference value that is compared
-with the contents of the stencil buffer for back-facing polygons. The
-initial value is 0. See @code{glStencilFuncSeparate}.
+with the contents of the stencil buffer for back-facing polygons. The
+initial value is 0. See @code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_BACK_VALUE_MASK}
@var{params} returns one value, the mask that is used for back-facing
polygons to mask both the stencil reference value and the stencil buffer
-value before they are compared. The initial value is all 1's. See
+value before they are compared. The initial value is all 1's. See
@code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_BACK_WRITEMASK}
@var{params} returns one value, the mask that controls writing of the
-stencil bitplanes for back-facing polygons. The initial value is all
-1's. See @code{glStencilMaskSeparate}.
+stencil bitplanes for back-facing polygons. The initial value is all
+1's. See @code{glStencilMaskSeparate}.
@item @code{GL_STENCIL_BITS}
@var{params} returns one value, the index to which the stencil bitplanes
-are cleared. The initial value is 0. See @code{glClearStencil}.
+are cleared. The initial value is 0. See @code{glClearStencil}.
@item @code{GL_STENCIL_FAIL}
@var{params} returns one value, a symbolic constant indicating what
-action is taken when the stencil test fails. The initial value is
-@code{GL_KEEP}. See @code{glStencilOp}. If the GL version is 2.0 or
+action is taken when the stencil test fails. The initial value is
+@code{GL_KEEP}. See @code{glStencilOp}. If the GL version is 2.0 or
greater, this stencil state only affects non-polygons and front-facing
-polygons. Back-facing polygons use separate stencil state. See
+polygons. Back-facing polygons use separate stencil state. See
@code{glStencilOpSeparate}.
@item @code{GL_STENCIL_FUNC}
@var{params} returns one value, a symbolic constant indicating what
function is used to compare the stencil reference value with the stencil
-buffer value. The initial value is @code{GL_ALWAYS}. See
-@code{glStencilFunc}. If the GL version is 2.0 or greater, this stencil
-state only affects non-polygons and front-facing polygons. Back-facing
-polygons use separate stencil state. See @code{glStencilFuncSeparate}.
+buffer value. The initial value is @code{GL_ALWAYS}. See
+@code{glStencilFunc}. If the GL version is 2.0 or greater, this stencil
+state only affects non-polygons and front-facing polygons. Back-facing
+polygons use separate stencil state. See @code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_PASS_DEPTH_FAIL}
@var{params} returns one value, a symbolic constant indicating what
action is taken when the stencil test passes, but the depth test fails.
-The initial value is @code{GL_KEEP}. See @code{glStencilOp}. If the GL
+The initial value is @code{GL_KEEP}. See @code{glStencilOp}. If the GL
version is 2.0 or greater, this stencil state only affects non-polygons
-and front-facing polygons. Back-facing polygons use separate stencil
-state. See @code{glStencilOpSeparate}.
+and front-facing polygons. Back-facing polygons use separate stencil
+state. See @code{glStencilOpSeparate}.
@item @code{GL_STENCIL_PASS_DEPTH_PASS}
@var{params} returns one value, a symbolic constant indicating what
action is taken when the stencil test passes and the depth test passes.
-The initial value is @code{GL_KEEP}. See @code{glStencilOp}. If the GL
+The initial value is @code{GL_KEEP}. See @code{glStencilOp}. If the GL
version is 2.0 or greater, this stencil state only affects non-polygons
-and front-facing polygons. Back-facing polygons use separate stencil
-state. See @code{glStencilOpSeparate}.
+and front-facing polygons. Back-facing polygons use separate stencil
+state. See @code{glStencilOpSeparate}.
@item @code{GL_STENCIL_REF}
@var{params} returns one value, the reference value that is compared
-with the contents of the stencil buffer. The initial value is 0. See
-@code{glStencilFunc}. If the GL version is 2.0 or greater, this stencil
-state only affects non-polygons and front-facing polygons. Back-facing
-polygons use separate stencil state. See @code{glStencilFuncSeparate}.
+with the contents of the stencil buffer. The initial value is 0. See
+@code{glStencilFunc}. If the GL version is 2.0 or greater, this stencil
+state only affects non-polygons and front-facing polygons. Back-facing
+polygons use separate stencil state. See @code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_TEST}
@var{params} returns a single boolean value indicating whether stencil
-testing of fragments is enabled. The initial value is @code{GL_FALSE}.
+testing of fragments is enabled. The initial value is @code{GL_FALSE}.
See @code{glStencilFunc} and @code{glStencilOp}.
@item @code{GL_STENCIL_VALUE_MASK}
@var{params} returns one value, the mask that is used to mask both the
stencil reference value and the stencil buffer value before they are
-compared. The initial value is all 1's. See @code{glStencilFunc}. If the
-GL version is 2.0 or greater, this stencil state only affects
-non-polygons and front-facing polygons. Back-facing polygons use
-separate stencil state. See @code{glStencilFuncSeparate}.
+compared. The initial value is all 1's. See @code{glStencilFunc}. If
+the GL version is 2.0 or greater, this stencil state only affects
+non-polygons and front-facing polygons. Back-facing polygons use
+separate stencil state. See @code{glStencilFuncSeparate}.
@item @code{GL_STENCIL_WRITEMASK}
@var{params} returns one value, the mask that controls writing of the
-stencil bitplanes. The initial value is all 1's. See
-@code{glStencilMask}. If the GL version is 2.0 or greater, this stencil
-state only affects non-polygons and front-facing polygons. Back-facing
-polygons use separate stencil state. See @code{glStencilMaskSeparate}.
+stencil bitplanes. The initial value is all 1's. See
+@code{glStencilMask}. If the GL version is 2.0 or greater, this stencil
+state only affects non-polygons and front-facing polygons. Back-facing
+polygons use separate stencil state. See @code{glStencilMaskSeparate}.
@item @code{GL_STEREO}
@var{params} returns one value, an estimate of the number of bits of
subpixel resolution that are used to position rasterized geometry in
-window coordinates. The value must be at least 4.
+window coordinates. The value must be at least 4.
@item @code{GL_TEXTURE_1D}
@var{params} returns a single boolean value indicating whether 1D
-texture mapping is enabled. The initial value is @code{GL_FALSE}. See
+texture mapping is enabled. The initial value is @code{GL_FALSE}. See
@code{glTexImage1D}.
@item @code{GL_TEXTURE_BINDING_1D}
@var{params} returns a single value, the name of the texture currently
-bound to the target @code{GL_TEXTURE_1D}. The initial value is 0. See
+bound to the target @code{GL_TEXTURE_1D}. The initial value is 0. See
@code{glBindTexture}.
@item @code{GL_TEXTURE_2D}
@var{params} returns a single boolean value indicating whether 2D
-texture mapping is enabled. The initial value is @code{GL_FALSE}. See
+texture mapping is enabled. The initial value is @code{GL_FALSE}. See
@code{glTexImage2D}.
@item @code{GL_TEXTURE_BINDING_2D}
@var{params} returns a single value, the name of the texture currently
-bound to the target @code{GL_TEXTURE_2D}. The initial value is 0. See
+bound to the target @code{GL_TEXTURE_2D}. The initial value is 0. See
@code{glBindTexture}.
@item @code{GL_TEXTURE_3D}
@var{params} returns a single boolean value indicating whether 3D
-texture mapping is enabled. The initial value is @code{GL_FALSE}. See
+texture mapping is enabled. The initial value is @code{GL_FALSE}. See
@code{glTexImage3D}.
@item @code{GL_TEXTURE_BINDING_3D}
@var{params} returns a single value, the name of the texture currently
-bound to the target @code{GL_TEXTURE_3D}. The initial value is 0. See
+bound to the target @code{GL_TEXTURE_3D}. The initial value is 0. See
@code{glBindTexture}.
@item @code{GL_TEXTURE_BINDING_CUBE_MAP}
@var{params} returns a single value, the name of the texture currently
-bound to the target @code{GL_TEXTURE_CUBE_MAP}. The initial value is 0.
+bound to the target @code{GL_TEXTURE_CUBE_MAP}. The initial value is 0.
See @code{glBindTexture}.
@item @code{GL_TEXTURE_COMPRESSION_HINT}
@var{params} returns a single value indicating the mode of the texture
-compression hint. The initial value is @code{GL_DONT_CARE}.
+compression hint. The initial value is @code{GL_DONT_CARE}.
@item @code{GL_TEXTURE_COORD_ARRAY}
@var{params} returns a single boolean value indicating whether the
-texture coordinate array is enabled. The initial value is
-@code{GL_FALSE}. See @code{glTexCoordPointer}.
+texture coordinate array is enabled. The initial value is
+@code{GL_FALSE}. See @code{glTexCoordPointer}.
@item @code{GL_TEXTURE_COORD_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the texture coordinate array. This buffer object would
+associated with the texture coordinate array. This buffer object would
have been bound to the target @code{GL_ARRAY_BUFFER} at the time of the
-most recent call to @code{glTexCoordPointer}. If no buffer object was
-bound to this target, 0 is returned. The initial value is 0. See
+most recent call to @code{glTexCoordPointer}. If no buffer object was
+bound to this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_TEXTURE_COORD_ARRAY_SIZE}
@var{params} returns one value, the number of coordinates per element in
-the texture coordinate array. The initial value is 4. See
+the texture coordinate array. The initial value is 4. See
@code{glTexCoordPointer}.
@item @code{GL_TEXTURE_COORD_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-elements in the texture coordinate array. The initial value is 0. See
+elements in the texture coordinate array. The initial value is 0. See
@code{glTexCoordPointer}.
@item @code{GL_TEXTURE_COORD_ARRAY_TYPE}
@var{params} returns one value, the data type of the coordinates in the
-texture coordinate array. The initial value is @code{GL_FLOAT}. See
+texture coordinate array. The initial value is @code{GL_FLOAT}. See
@code{glTexCoordPointer}.
@item @code{GL_TEXTURE_CUBE_MAP}
@var{params} returns a single boolean value indicating whether
-cube-mapped texture mapping is enabled. The initial value is
-@code{GL_FALSE}. See @code{glTexImage2D}.
+cube-mapped texture mapping is enabled. The initial value is
+@code{GL_FALSE}. See @code{glTexImage2D}.
@item @code{GL_TEXTURE_GEN_Q}
@var{params} returns a single boolean value indicating whether automatic
-generation of the @var{q} texture coordinate is enabled. The initial
-value is @code{GL_FALSE}. See @code{glTexGen}.
+generation of the @var{q} texture coordinate is enabled. The initial
+value is @code{GL_FALSE}. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_R}
@var{params} returns a single boolean value indicating whether automatic
-generation of the @var{r} texture coordinate is enabled. The initial
-value is @code{GL_FALSE}. See @code{glTexGen}.
+generation of the @var{r} texture coordinate is enabled. The initial
+value is @code{GL_FALSE}. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_S}
@var{params} returns a single boolean value indicating whether automatic
-generation of the @var{S} texture coordinate is enabled. The initial
-value is @code{GL_FALSE}. See @code{glTexGen}.
+generation of the @var{S} texture coordinate is enabled. The initial
+value is @code{GL_FALSE}. See @code{glTexGen}.
@item @code{GL_TEXTURE_GEN_T}
@var{params} returns a single boolean value indicating whether automatic
-generation of the T texture coordinate is enabled. The initial value is
-@code{GL_FALSE}. See @code{glTexGen}.
+generation of the T texture coordinate is enabled. The initial value is
+@code{GL_FALSE}. See @code{glTexGen}.
@item @code{GL_TEXTURE_MATRIX}
@var{params} returns sixteen values: the texture matrix on the top of
-the texture matrix stack. Initially this matrix is the identity matrix.
+the texture matrix stack. Initially this matrix is the identity matrix.
See @code{glPushMatrix}.
@item @code{GL_TEXTURE_STACK_DEPTH}
@var{params} returns one value, the number of matrices on the texture
-matrix stack. The initial value is 1. See @code{glPushMatrix}.
+matrix stack. The initial value is 1. See @code{glPushMatrix}.
@item @code{GL_TRANSPOSE_COLOR_MATRIX}
@var{params} returns 16 values, the elements of the color matrix in
-row-major order. See @code{glLoadTransposeMatrix}.
+row-major order. See @code{glLoadTransposeMatrix}.
@item @code{GL_TRANSPOSE_MODELVIEW_MATRIX}
@var{params} returns 16 values, the elements of the modelview matrix in
-row-major order. See @code{glLoadTransposeMatrix}.
+row-major order. See @code{glLoadTransposeMatrix}.
@item @code{GL_TRANSPOSE_PROJECTION_MATRIX}
@var{params} returns 16 values, the elements of the projection matrix in
-row-major order. See @code{glLoadTransposeMatrix}.
+row-major order. See @code{glLoadTransposeMatrix}.
@item @code{GL_TRANSPOSE_TEXTURE_MATRIX}
@var{params} returns 16 values, the elements of the texture matrix in
-row-major order. See @code{glLoadTransposeMatrix}.
+row-major order. See @code{glLoadTransposeMatrix}.
@item @code{GL_UNPACK_ALIGNMENT}
@var{params} returns one value, the byte alignment used for reading
-pixel data from memory. The initial value is 4. See @code{glPixelStore}.
+pixel data from memory. The initial value is 4. See
+@code{glPixelStore}.
@item @code{GL_UNPACK_IMAGE_HEIGHT}
@var{params} returns one value, the image height used for reading pixel
-data from memory. The initial is 0. See @code{glPixelStore}.
+data from memory. The initial is 0. See @code{glPixelStore}.
@item @code{GL_UNPACK_LSB_FIRST}
@var{params} returns a single boolean value indicating whether
single-bit pixels being read from memory are read first from the least
-significant bit of each unsigned byte. The initial value is
-@code{GL_FALSE}. See @code{glPixelStore}.
+significant bit of each unsigned byte. The initial value is
+@code{GL_FALSE}. See @code{glPixelStore}.
@item @code{GL_UNPACK_ROW_LENGTH}
@var{params} returns one value, the row length used for reading pixel
-data from memory. The initial value is 0. See @code{glPixelStore}.
+data from memory. The initial value is 0. See @code{glPixelStore}.
@item @code{GL_UNPACK_SKIP_IMAGES}
@var{params} returns one value, the number of pixel images skipped
-before the first pixel is read from memory. The initial value is 0. See
+before the first pixel is read from memory. The initial value is 0. See
@code{glPixelStore}.
@item @code{GL_UNPACK_SKIP_PIXELS}
@var{params} returns one value, the number of pixel locations skipped
-before the first pixel is read from memory. The initial value is 0. See
+before the first pixel is read from memory. The initial value is 0. See
@code{glPixelStore}.
@item @code{GL_UNPACK_SKIP_ROWS}
@var{params} returns one value, the number of rows of pixel locations
-skipped before the first pixel is read from memory. The initial value is
-0. See @code{glPixelStore}.
+skipped before the first pixel is read from memory. The initial value
+is 0. See @code{glPixelStore}.
@item @code{GL_UNPACK_SWAP_BYTES}
@var{params} returns a single boolean value indicating whether the bytes
of two-byte and four-byte pixel indices and components are swapped after
-being read from memory. The initial value is @code{GL_FALSE}. See
+being read from memory. The initial value is @code{GL_FALSE}. See
@code{glPixelStore}.
@item @code{GL_VERTEX_ARRAY}
@var{params} returns a single boolean value indicating whether the
-vertex array is enabled. The initial value is @code{GL_FALSE}. See
+vertex array is enabled. The initial value is @code{GL_FALSE}. See
@code{glVertexPointer}.
@item @code{GL_VERTEX_ARRAY_BUFFER_BINDING}
@var{params} returns a single value, the name of the buffer object
-associated with the vertex array. This buffer object would have been
+associated with the vertex array. This buffer object would have been
bound to the target @code{GL_ARRAY_BUFFER} at the time of the most
-recent call to @code{glVertexPointer}. If no buffer object was bound to
-this target, 0 is returned. The initial value is 0. See
+recent call to @code{glVertexPointer}. If no buffer object was bound to
+this target, 0 is returned. The initial value is 0. See
@code{glBindBuffer}.
@item @code{GL_VERTEX_ARRAY_SIZE}
@var{params} returns one value, the number of coordinates per vertex in
-the vertex array. The initial value is 4. See @code{glVertexPointer}.
+the vertex array. The initial value is 4. See @code{glVertexPointer}.
@item @code{GL_VERTEX_ARRAY_STRIDE}
@var{params} returns one value, the byte offset between consecutive
-vertices in the vertex array. The initial value is 0. See
+vertices in the vertex array. The initial value is 0. See
@code{glVertexPointer}.
@item @code{GL_VERTEX_ARRAY_TYPE}
@var{params} returns one value, the data type of each coordinate in the
-vertex array. The initial value is @code{GL_FLOAT}. See
+vertex array. The initial value is @code{GL_FLOAT}. See
@code{glVertexPointer}.
@item @code{GL_VERTEX_PROGRAM_POINT_SIZE}
@var{params} returns a single boolean value indicating whether vertex
-program point size mode is enabled. If enabled, and a vertex shader is
+program point size mode is enabled. If enabled, and a vertex shader is
active, then the point size is taken from the shader built-in
-@code{gl_PointSize}. If disabled, and a vertex shader is active, then
+@code{gl_PointSize}. If disabled, and a vertex shader is active, then
the point size is taken from the point state as specified by
-@code{glPointSize}. The initial value is @code{GL_FALSE}.
+@code{glPointSize}. The initial value is @code{GL_FALSE}.
@item @code{GL_VERTEX_PROGRAM_TWO_SIDE}
@var{params} returns a single boolean value indicating whether vertex
-program two-sided color mode is enabled. If enabled, and a vertex shader
-is active, then the GL chooses the back color output for back-facing
-polygons, and the front color output for non-polygons and front-facing
-polygons. If disabled, and a vertex shader is active, then the front
-color output is always selected. The initial value is @code{GL_FALSE}.
+program two-sided color mode is enabled. If enabled, and a vertex
+shader is active, then the GL chooses the back color output for
+back-facing polygons, and the front color output for non-polygons and
+front-facing polygons. If disabled, and a vertex shader is active, then
+the front color output is always selected. The initial value is
+@code{GL_FALSE}.
@item @code{GL_VIEWPORT}
@var{params} returns four values: the @r{@var{x}} and @r{@var{y}} window
-coordinates of the viewport, followed by its width and height. Initially
+coordinates of the viewport, followed by its width and height. Initially
the @r{@var{x}} and @r{@var{y}} window coordinates are both set to 0,
and the width and height are set to the width and height of the window
-into which the GL will do its rendering. See @code{glViewport}.
+into which the GL will do its rendering. See @code{glViewport}.
@item @code{GL_ZOOM_X}
-@var{params} returns one value, the @r{@var{x}} pixel zoom factor. The
-initial value is 1. See @code{glPixelZoom}.
+@var{params} returns one value, the @r{@var{x}} pixel zoom factor. The
+initial value is 1. See @code{glPixelZoom}.
@item @code{GL_ZOOM_Y}
-@var{params} returns one value, the @r{@var{y}} pixel zoom factor. The
-initial value is 1. See @code{glPixelZoom}.
+@var{params} returns one value, the @r{@var{y}} pixel zoom factor. The
+initial value is 1. See @code{glPixelZoom}.
@end table
@end table
Certain aspects of GL behavior, when there is room for interpretation,
-can be controlled with hints. A hint is specified with two arguments.
+can be controlled with hints. A hint is specified with two arguments.
@var{target} is a symbolic constant indicating the behavior to be
controlled, and @var{mode} is another symbolic constant indicating the
-desired behavior. The initial value for each @var{target} is
-@code{GL_DONT_CARE}. @var{mode} can be one of the following:
+desired behavior. The initial value for each @var{target} is
+@code{GL_DONT_CARE}. @var{mode} can be one of the following:
@table @asis
@item @code{GL_FASTEST}
@end table
Though the implementation aspects that can be hinted are well defined,
-the interpretation of the hints depends on the implementation. The hint
+the interpretation of the hints depends on the implementation. The hint
aspects that can be specified with @var{target}, along with suggested
semantics, are as follows:
@item @code{GL_FOG_HINT}
-Indicates the accuracy of fog calculation. If per-pixel fog calculation
+Indicates the accuracy of fog calculation. If per-pixel fog calculation
is not efficiently supported by the GL implementation, hinting
@code{GL_DONT_CARE} or @code{GL_FASTEST} can result in per-vertex
calculation of fog effects.
@item @code{GL_LINE_SMOOTH_HINT}
-Indicates the sampling quality of antialiased lines. If a larger filter
+Indicates the sampling quality of antialiased lines. If a larger filter
function is applied, hinting @code{GL_NICEST} can result in more pixel
fragments being generated during rasterization.
Indicates the quality of color, texture coordinate, and fog coordinate
-interpolation. If perspective-corrected parameter interpolation is not
+interpolation. If perspective-corrected parameter interpolation is not
efficiently supported by the GL implementation, hinting
@code{GL_DONT_CARE} or @code{GL_FASTEST} can result in simple linear
interpolation of colors and/or texture coordinates.
@item @code{GL_POINT_SMOOTH_HINT}
-Indicates the sampling quality of antialiased points. If a larger filter
-function is applied, hinting @code{GL_NICEST} can result in more pixel
-fragments being generated during rasterization.
+Indicates the sampling quality of antialiased points. If a larger
+filter function is applied, hinting @code{GL_NICEST} can result in more
+pixel fragments being generated during rasterization.
@item @code{GL_POLYGON_SMOOTH_HINT}
-Indicates the sampling quality of antialiased polygons. Hinting
+Indicates the sampling quality of antialiased polygons. Hinting
@code{GL_NICEST} can result in more pixel fragments being generated
during rasterization, if a larger filter function is applied.
Hinting @code{GL_FASTEST} indicates that texture images should be
compressed as quickly as possible, while @code{GL_NICEST} indicates that
texture images should be compressed with as little image quality loss as
-possible. @code{GL_NICEST} should be selected if the texture is to be
+possible. @code{GL_NICEST} should be selected if the texture is to be
retrieved by @code{glGetCompressedTexImage} for reuse.
@end table
@table @asis
@item @var{target}
-The histogram whose parameters are to be set. Must be one of
+The histogram whose parameters are to be set. Must be one of
@code{GL_HISTOGRAM} or @code{GL_PROXY_HISTOGRAM}.
@item @var{width}
-The number of entries in the histogram table. Must be a power of 2.
+The number of entries in the histogram table. Must be a power of 2.
@item @var{internalformat}
-The format of entries in the histogram table. Must be one of
+The format of entries in the histogram table. Must be one of
@code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_LUMINANCE}, @code{GL_LUMINANCE4},
@code{GL_LUMINANCE8}, @code{GL_LUMINANCE12}, @code{GL_LUMINANCE16},
@item @var{sink}
If @code{GL_TRUE}, pixels will be consumed by the histogramming process
-and no drawing or texture loading will take place. If @code{GL_FALSE},
+and no drawing or texture loading will take place. If @code{GL_FALSE},
pixels will proceed to the minmax process after histogramming.
@end table
When @code{GL_HISTOGRAM} is enabled, RGBA color components are converted
to histogram table indices by clamping to the range [0,1], multiplying
by the width of the histogram table, and rounding to the nearest
-integer. The table entries selected by the RGBA indices are then
-incremented. (If the internal format of the histogram table includes
+integer. The table entries selected by the RGBA indices are then
+incremented. (If the internal format of the histogram table includes
luminance, then the index derived from the R color component determines
the luminance table entry to be incremented.) If a histogram table entry
is incremented beyond its maximum value, then its value becomes
-undefined. (This is not an error.)
+undefined. (This is not an error.)
Histogramming is performed only for RGBA pixels (though these may be
specified originally as color indices and converted to RGBA by index
-table lookup). Histogramming is enabled with @code{glEnable} and
+table lookup). Histogramming is enabled with @code{glEnable} and
disabled with @code{glDisable}.
When @var{target} is @code{GL_HISTOGRAM}, @code{glHistogram} redefines
the current histogram table to have @var{width} entries of the format
-specified by @var{internalformat}. The entries are indexed 0 through
-@r{@var{width}-1}, and all entries are initialized to zero. The values
-in the previous histogram table, if any, are lost. If @var{sink} is
+specified by @var{internalformat}. The entries are indexed 0 through
+@r{@var{width}-1}, and all entries are initialized to zero. The values
+in the previous histogram table, if any, are lost. If @var{sink} is
@code{GL_TRUE}, then pixels are discarded after histogramming; no
further processing of the pixels takes place, and no drawing, texture
loading, or pixel readback will result.
When @var{target} is @code{GL_PROXY_HISTOGRAM}, @code{glHistogram}
computes all state information as if the histogram table were to be
-redefined, but does not actually define the new table. If the requested
+redefined, but does not actually define the new table. If the requested
histogram table is too large to be supported, then the state information
-will be set to zero. This provides a way to determine if a histogram
+will be set to zero. This provides a way to determine if a histogram
table with the given parameters can be supported.
@table @asis
@item @var{mask}
Specifies a bit mask to enable and disable the writing of individual
-bits in the color index buffers. Initially, the mask is all 1's.
+bits in the color index buffers. Initially, the mask is all 1's.
@end table
@code{glIndexMask} controls the writing of individual bits in the color
-index buffers. The least significant @r{@var{n}} bits of @var{mask},
+index buffers. The least significant @r{@var{n}} bits of @var{mask},
where @r{@var{n}} is the number of bits in a color index buffer, specify
-a mask. Where a 1 (one) appears in the mask, it's possible to write to
-the corresponding bit in the color index buffer (or buffers). Where a 0
+a mask. Where a 1 (one) appears in the mask, it's possible to write to
+the corresponding bit in the color index buffer (or buffers). Where a 0
(zero) appears, the corresponding bit is write-protected.
This mask is used only in color index mode, and it affects only the
@table @asis
@item @var{type}
-Specifies the data type of each color index in the array. Symbolic
+Specifies the data type of each color index in the array. Symbolic
constants @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT}, @code{GL_INT},
-@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value is
-@code{GL_FLOAT}.
+@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value
+is @code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive color indexes. If
+Specifies the byte offset between consecutive color indexes. If
@var{stride} is 0, the color indexes are understood to be tightly packed
-in the array. The initial value is 0.
+in the array. The initial value is 0.
@item @var{pointer}
-Specifies a pointer to the first index in the array. The initial value
+Specifies a pointer to the first index in the array. The initial value
is 0.
@end table
@code{glIndexPointer} specifies the location and data format of an array
-of color indexes to use when rendering. @var{type} specifies the data
+of color indexes to use when rendering. @var{type} specifies the data
type of each color index and @var{stride} specifies the byte stride from
one color index to the next, allowing vertices and attributes to be
packed into a single array or stored in separate arrays.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a color index array is specified,
@var{pointer} is treated as a byte offset into the buffer object's data
-store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
+store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
is saved as color index vertex array client-side state
(@code{GL_INDEX_ARRAY_BUFFER_BINDING}).
To enable and disable the color index array, call
@code{glEnableClientState} and @code{glDisableClientState} with the
-argument @code{GL_INDEX_ARRAY}. If enabled, the color index array is
+argument @code{GL_INDEX_ARRAY}. If enabled, the color index array is
used when @code{glDrawArrays}, @code{glMultiDrawArrays},
@code{glDrawElements}, @code{glMultiDrawElements},
@code{glDrawRangeElements}, or @code{glArrayElement} is called.
@end table
-@code{glIndex} updates the current (single-valued) color index. It takes
-one argument, the new value for the current color index.
+@code{glIndex} updates the current (single-valued) color index. It
+takes one argument, the new value for the current color index.
-The current index is stored as a floating-point value. Integer values
+The current index is stored as a floating-point value. Integer values
are converted directly to floating-point values, with no special
-mapping. The initial value is 1.
+mapping. The initial value is 1.
Index values outside the representable range of the color index buffer
-are not clamped. However, before an index is dithered (if enabled) and
-written to the frame buffer, it is converted to fixed-point format. Any
+are not clamped. However, before an index is dithered (if enabled) and
+written to the frame buffer, it is converted to fixed-point format. Any
bits in the integer portion of the resulting fixed-point value that do
not correspond to bits in the frame buffer are masked out.
Initialize the name stack.
The name stack is used during selection mode to allow sets of rendering
-commands to be uniquely identified. It consists of an ordered set of
-unsigned integers. @code{glInitNames} causes the name stack to be
+commands to be uniquely identified. It consists of an ordered set of
+unsigned integers. @code{glInitNames} causes the name stack to be
initialized to its default empty state.
The name stack is always empty while the render mode is not
-@code{GL_SELECT}. Calls to @code{glInitNames} while the render mode is
+@code{GL_SELECT}. Calls to @code{glInitNames} while the render mode is
not @code{GL_SELECT} are ignored.
@code{GL_INVALID_OPERATION} is generated if @code{glInitNames} is
@table @asis
@item @var{format}
-Specifies the type of array to enable. Symbolic constants @code{GL_V2F},
-@code{GL_V3F}, @code{GL_C4UB_V2F}, @code{GL_C4UB_V3F},
+Specifies the type of array to enable. Symbolic constants
+@code{GL_V2F}, @code{GL_V3F}, @code{GL_C4UB_V2F}, @code{GL_C4UB_V3F},
@code{GL_C3F_V3F}, @code{GL_N3F_V3F}, @code{GL_C4F_N3F_V3F},
@code{GL_T2F_V3F}, @code{GL_T4F_V4F}, @code{GL_T2F_C4UB_V3F},
@code{GL_T2F_C3F_V3F}, @code{GL_T2F_N3F_V3F}, @code{GL_T2F_C4F_N3F_V3F},
@code{glInterleavedArrays} lets you specify and enable individual color,
normal, texture and vertex arrays whose elements are part of a larger
-aggregate array element. For some implementations, this is more
+aggregate array element. For some implementations, this is more
efficient than specifying the arrays separately.
If @var{stride} is 0, the aggregate elements are stored consecutively.
element.
@var{format} serves as a ``key'' describing the extraction of individual
-arrays from the aggregate array. If @var{format} contains a T, then
-texture coordinates are extracted from the interleaved array. If C is
-present, color values are extracted. If N is present, normal coordinates
-are extracted. Vertex coordinates are always extracted.
+arrays from the aggregate array. If @var{format} contains a T, then
+texture coordinates are extracted from the interleaved array. If C is
+present, color values are extracted. If N is present, normal
+coordinates are extracted. Vertex coordinates are always extracted.
-The digits 2, 3, and 4 denote how many values are extracted. F indicates
-that values are extracted as floating-point values. Colors may also be
-extracted as 4 unsigned bytes if 4UB follows the C. If a color is
-extracted as 4 unsigned bytes, the vertex array element which follows is
-located at the first possible floating-point aligned address.
+The digits 2, 3, and 4 denote how many values are extracted. F
+indicates that values are extracted as floating-point values. Colors
+may also be extracted as 4 unsigned bytes if 4UB follows the C. If a
+color is extracted as 4 unsigned bytes, the vertex array element which
+follows is located at the first possible floating-point aligned address.
@code{GL_INVALID_ENUM} is generated if @var{format} is not an accepted
value.
@end table
@code{glIsBuffer} returns @code{GL_TRUE} if @var{buffer} is currently
-the name of a buffer object. If @var{buffer} is zero, or is a non-zero
+the name of a buffer object. If @var{buffer} is zero, or is a non-zero
value that is not currently the name of a buffer object, or if an error
occurs, @code{glIsBuffer} returns @code{GL_FALSE}.
@end table
@code{glIsEnabled} returns @code{GL_TRUE} if @var{cap} is an enabled
-capability and returns @code{GL_FALSE} otherwise. Initially all
+capability and returns @code{GL_FALSE} otherwise. Initially all
capabilities except @code{GL_DITHER} are disabled; @code{GL_DITHER} is
initially enabled.
@code{glIsProgram} returns @code{GL_TRUE} if @var{program} is the name
of a program object previously created with @code{glCreateProgram} and
-not yet deleted with @code{glDeleteProgram}. If @var{program} is zero or
-a non-zero value that is not the name of a program object, or if an
+not yet deleted with @code{glDeleteProgram}. If @var{program} is zero
+or a non-zero value that is not the name of a program object, or if an
error occurs, @code{glIsProgram} returns @code{GL_FALSE}.
@code{GL_INVALID_OPERATION} is generated if @code{glIsProgram} is
@end table
@code{glIsQuery} returns @code{GL_TRUE} if @var{id} is currently the
-name of a query object. If @var{id} is zero, or is a non-zero value that
-is not currently the name of a query object, or if an error occurs,
+name of a query object. If @var{id} is zero, or is a non-zero value
+that is not currently the name of a query object, or if an error occurs,
@code{glIsQuery} returns @code{GL_FALSE}.
A name returned by @code{glGenQueries}, but not yet associated with a
@code{glIsShader} returns @code{GL_TRUE} if @var{shader} is the name of
a shader object previously created with @code{glCreateShader} and not
-yet deleted with @code{glDeleteShader}. If @var{shader} is zero or a
+yet deleted with @code{glDeleteShader}. If @var{shader} is zero or a
non-zero value that is not the name of a shader object, or if an error
occurs, @code{glIsShader } returns @code{GL_FALSE}.
@end table
@code{glIsTexture} returns @code{GL_TRUE} if @var{texture} is currently
-the name of a texture. If @var{texture} is zero, or is a non-zero value
+the name of a texture. If @var{texture} is zero, or is a non-zero value
that is not currently the name of a texture, or if an error occurs,
@code{glIsTexture} returns @code{GL_FALSE}.
@end table
-@code{glLightModel} sets the lighting model parameter. @var{pname} names
-a parameter and @var{params} gives the new value. There are three
+@code{glLightModel} sets the lighting model parameter. @var{pname}
+names a parameter and @var{params} gives the new value. There are three
lighting model parameters:
@table @asis
@var{params} contains four integer or floating-point values that specify
-the ambient RGBA intensity of the entire scene. Integer values are
+the ambient RGBA intensity of the entire scene. Integer values are
mapped linearly such that the most positive representable value maps to
1.0, and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial ambient scene intensity
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial ambient scene intensity
is (0.2, 0.2, 0.2, 1.0).
@item @code{GL_LIGHT_MODEL_COLOR_CONTROL}
@var{params} must be either @code{GL_SEPARATE_SPECULAR_COLOR} or
-@code{GL_SINGLE_COLOR}. @code{GL_SINGLE_COLOR} specifies that a single
+@code{GL_SINGLE_COLOR}. @code{GL_SINGLE_COLOR} specifies that a single
color is generated from the lighting computation for a vertex.
@code{GL_SEPARATE_SPECULAR_COLOR} specifies that the specular color
computation of lighting be stored separately from the remainder of the
-lighting computation. The specular color is summed into the generated
+lighting computation. The specular color is summed into the generated
fragment's color after the application of texture mapping (if enabled).
The initial value is @code{GL_SINGLE_COLOR}.
@var{params} is a single integer or floating-point value that specifies
-how specular reflection angles are computed. If @var{params} is 0 (or
+how specular reflection angles are computed. If @var{params} is 0 (or
0.0), specular reflection angles take the view direction to be parallel
to and in the direction of the -@var{z} axis, regardless of the location
-of the vertex in eye coordinates. Otherwise, specular reflections are
-computed from the origin of the eye coordinate system. The initial value
-is 0.
+of the vertex in eye coordinates. Otherwise, specular reflections are
+computed from the origin of the eye coordinate system. The initial
+value is 0.
@item @code{GL_LIGHT_MODEL_TWO_SIDE}
@var{params} is a single integer or floating-point value that specifies
whether one- or two-sided lighting calculations are done for polygons.
It has no effect on the lighting calculations for points, lines, or
-bitmaps. If @var{params} is 0 (or 0.0), one-sided lighting is specified,
-and only the @var{front} material parameters are used in the lighting
-equation. Otherwise, two-sided lighting is specified. In this case,
-vertices of back-facing polygons are lighted using the @var{back}
+bitmaps. If @var{params} is 0 (or 0.0), one-sided lighting is
+specified, and only the @var{front} material parameters are used in the
+lighting equation. Otherwise, two-sided lighting is specified. In this
+case, vertices of back-facing polygons are lighted using the @var{back}
material parameters and have their normals reversed before the lighting
-equation is evaluated. Vertices of front-facing polygons are always
+equation is evaluated. Vertices of front-facing polygons are always
lighted using the @var{front} material parameters, with no change to
-their normals. The initial value is 0.
+their normals. The initial value is 0.
@end table
In RGBA mode, the lighted color of a vertex is the sum of the material
emission intensity, the product of the material ambient reflectance and
the lighting model full-scene ambient intensity, and the contribution of
-each enabled light source. Each light source contributes the sum of
-three terms: ambient, diffuse, and specular. The ambient light source
+each enabled light source. Each light source contributes the sum of
+three terms: ambient, diffuse, and specular. The ambient light source
contribution is the product of the material ambient reflectance and the
-light's ambient intensity. The diffuse light source contribution is the
+light's ambient intensity. The diffuse light source contribution is the
product of the material diffuse reflectance, the light's diffuse
intensity, and the dot product of the vertex's normal with the
-normalized vector from the vertex to the light source. The specular
+normalized vector from the vertex to the light source. The specular
light source contribution is the product of the material specular
reflectance, the light's specular intensity, and the dot product of the
normalized vertex-to-eye and vertex-to-light vectors, raised to the
-power of the shininess of the material. All three light source
+power of the shininess of the material. All three light source
contributions are attenuated equally based on the distance from the
vertex to the light source and on light source direction, spread
-exponent, and spread cutoff angle. All dot products are replaced with 0
+exponent, and spread cutoff angle. All dot products are replaced with 0
if they evaluate to a negative value.
The alpha component of the resulting lighted color is set to the alpha
In color index mode, the value of the lighted index of a vertex ranges
from the ambient to the specular values passed to @code{glMaterial}
-using @code{GL_COLOR_INDEXES}. Diffuse and specular coefficients,
+using @code{GL_COLOR_INDEXES}. Diffuse and specular coefficients,
computed with a (.30, .59, .11) weighting of the lights' colors, the
shininess of the material, and the same reflection and attenuation
equations as in the RGBA case, determine how much above ambient the
@table @asis
@item @var{light}
-Specifies a light. The number of lights depends on the implementation,
-but at least eight lights are supported. They are identified by symbolic
-names of the form @code{GL_LIGHT}@r{@var{i}}, where i ranges from 0 to
-the value of @code{GL_MAX_LIGHTS} - 1.
+Specifies a light. The number of lights depends on the implementation,
+but at least eight lights are supported. They are identified by
+symbolic names of the form @code{GL_LIGHT}@r{@var{i}}, where i ranges
+from 0 to the value of @code{GL_MAX_LIGHTS} - 1.
@item @var{pname}
Specifies a single-valued light source parameter for @var{light}.
@code{glLight} sets the values of individual light source parameters.
@var{light} names the light and is a symbolic name of the form
@code{GL_LIGHT}@r{@var{i}}, where i ranges from 0 to the value of
-@code{GL_MAX_LIGHTS} - 1. @var{pname} specifies one of ten light source
-parameters, again by symbolic name. @var{params} is either a single
+@code{GL_MAX_LIGHTS} - 1. @var{pname} specifies one of ten light source
+parameters, again by symbolic name. @var{params} is either a single
value or a pointer to an array that contains the new values.
To enable and disable lighting calculation, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_LIGHTING}. Lighting is initially
-disabled. When it is enabled, light sources that are enabled contribute
-to the lighting calculation. Light source @r{@var{i}} is enabled and
-disabled using @code{glEnable} and @code{glDisable} with argument
-@code{GL_LIGHT}@r{@var{i}}.
+@code{glDisable} with argument @code{GL_LIGHTING}. Lighting is
+initially disabled. When it is enabled, light sources that are enabled
+contribute to the lighting calculation. Light source @r{@var{i}} is
+enabled and disabled using @code{glEnable} and @code{glDisable} with
+argument @code{GL_LIGHT}@r{@var{i}}.
The ten light parameters are as follows:
@table @asis
@item @code{GL_AMBIENT}
@var{params} contains four integer or floating-point values that specify
-the ambient RGBA intensity of the light. Integer values are mapped
+the ambient RGBA intensity of the light. Integer values are mapped
linearly such that the most positive representable value maps to 1.0,
and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial ambient light intensity
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial ambient light intensity
is (0, 0, 0, 1).
@item @code{GL_DIFFUSE}
@var{params} contains four integer or floating-point values that specify
-the diffuse RGBA intensity of the light. Integer values are mapped
+the diffuse RGBA intensity of the light. Integer values are mapped
linearly such that the most positive representable value maps to 1.0,
and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial value for
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial value for
@code{GL_LIGHT0} is (1, 1, 1, 1); for other lights, the initial value is
(0, 0, 0, 1).
@item @code{GL_SPECULAR}
@var{params} contains four integer or floating-point values that specify
-the specular RGBA intensity of the light. Integer values are mapped
+the specular RGBA intensity of the light. Integer values are mapped
linearly such that the most positive representable value maps to 1.0,
and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial value for
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial value for
@code{GL_LIGHT0} is (1, 1, 1, 1); for other lights, the initial value is
(0, 0, 0, 1).
@item @code{GL_POSITION}
@var{params} contains four integer or floating-point values that specify
-the position of the light in homogeneous object coordinates. Both
-integer and floating-point values are mapped directly. Neither integer
+the position of the light in homogeneous object coordinates. Both
+integer and floating-point values are mapped directly. Neither integer
nor floating-point values are clamped.
The position is transformed by the modelview matrix when @code{glLight}
is called (just as if it were a point), and it is stored in eye
-coordinates. If the @r{@var{w}} component of the position is 0, the
-light is treated as a directional source. Diffuse and specular lighting
+coordinates. If the @r{@var{w}} component of the position is 0, the
+light is treated as a directional source. Diffuse and specular lighting
calculations take the light's direction, but not its actual position,
-into account, and attenuation is disabled. Otherwise, diffuse and
+into account, and attenuation is disabled. Otherwise, diffuse and
specular lighting calculations are based on the actual location of the
-light in eye coordinates, and attenuation is enabled. The initial
+light in eye coordinates, and attenuation is enabled. The initial
position is (0, 0, 1, 0); thus, the initial light source is directional,
parallel to, and in the direction of the @r{-@var{z}} axis.
@item @code{GL_SPOT_DIRECTION}
@var{params} contains three integer or floating-point values that
specify the direction of the light in homogeneous object coordinates.
-Both integer and floating-point values are mapped directly. Neither
+Both integer and floating-point values are mapped directly. Neither
integer nor floating-point values are clamped.
The spot direction is transformed by the upper 3x3 of the modelview
matrix when @code{glLight} is called, and it is stored in eye
-coordinates. It is significant only when @code{GL_SPOT_CUTOFF} is not
-180, which it is initially. The initial direction is @r{(0,0-1)}.
+coordinates. It is significant only when @code{GL_SPOT_CUTOFF} is not
+180, which it is initially. The initial direction is @r{(0,0-1)}.
@item @code{GL_SPOT_EXPONENT}
@var{params} is a single integer or floating-point value that specifies
-the intensity distribution of the light. Integer and floating-point
-values are mapped directly. Only values in the range @r{[0,128]} are
+the intensity distribution of the light. Integer and floating-point
+values are mapped directly. Only values in the range @r{[0,128]} are
accepted.
Effective light intensity is attenuated by the cosine of the angle
the vertex being lighted, raised to the power of the spot exponent.
Thus, higher spot exponents result in a more focused light source,
regardless of the spot cutoff angle (see @code{GL_SPOT_CUTOFF}, next
-paragraph). The initial spot exponent is 0, resulting in uniform light
+paragraph). The initial spot exponent is 0, resulting in uniform light
distribution.
@item @code{GL_SPOT_CUTOFF}
@var{params} is a single integer or floating-point value that specifies
-the maximum spread angle of a light source. Integer and floating-point
-values are mapped directly. Only values in the range @r{[0,90]} and the
-special value 180 are accepted. If the angle between the direction of
+the maximum spread angle of a light source. Integer and floating-point
+values are mapped directly. Only values in the range @r{[0,90]} and the
+special value 180 are accepted. If the angle between the direction of
the light and the direction from the light to the vertex being lighted
is greater than the spot cutoff angle, the light is completely masked.
Otherwise, its intensity is controlled by the spot exponent and the
-attenuation factors. The initial spot cutoff is 180, resulting in
+attenuation factors. The initial spot cutoff is 180, resulting in
uniform light distribution.
@item @code{GL_CONSTANT_ATTENUATION}
@item @code{GL_LINEAR_ATTENUATION}
@item @code{GL_QUADRATIC_ATTENUATION}
@var{params} is a single integer or floating-point value that specifies
-one of the three light attenuation factors. Integer and floating-point
-values are mapped directly. Only nonnegative values are accepted. If the
-light is positional, rather than directional, its intensity is
+one of the three light attenuation factors. Integer and floating-point
+values are mapped directly. Only nonnegative values are accepted. If
+the light is positional, rather than directional, its intensity is
attenuated by the reciprocal of the sum of the constant factor, the
linear factor times the distance between the light and the vertex being
lighted, and the quadratic factor times the square of the same distance.
@table @asis
@item @var{factor}
-Specifies a multiplier for each bit in the line stipple pattern. If
+Specifies a multiplier for each bit in the line stipple pattern. If
@var{factor} is 3, for example, each bit in the pattern is used three
-times before the next bit in the pattern is used. @var{factor} is
+times before the next bit in the pattern is used. @var{factor} is
clamped to the range [1, 256] and defaults to 1.
@item @var{pattern}
Specifies a 16-bit integer whose bit pattern determines which fragments
-of a line will be drawn when the line is rasterized. Bit zero is used
+of a line will be drawn when the line is rasterized. Bit zero is used
first; the default pattern is all 1's.
@end table
Line stippling masks out certain fragments produced by rasterization;
-those fragments will not be drawn. The masking is achieved by using
+those fragments will not be drawn. The masking is achieved by using
three parameters: the 16-bit line stipple pattern @var{pattern}, the
repeat count @var{factor}, and an integer stipple counter @r{@var{s}}.
Counter @r{@var{s}} is reset to 0 whenever @code{glBegin} is called and
before each line segment of a
-@code{glBegin}(@code{GL_LINES})/@code{glEnd} sequence is generated. It
+@code{glBegin}(@code{GL_LINES})/@code{glEnd} sequence is generated. It
is incremented after each fragment of a unit width aliased line segment
is generated or after each @r{@var{i}} fragments of an @r{@var{i}} width
-line segment are generated. The @r{@var{i}} fragments associated with
+line segment are generated. The @r{@var{i}} fragments associated with
count @r{@var{s}} are masked out if
@var{pattern} bit @r{(@var{s}/@var{factor},)%16}
-is 0, otherwise these fragments are sent to the frame buffer. Bit zero
+is 0, otherwise these fragments are sent to the frame buffer. Bit zero
of @var{pattern} is the least significant bit.
Antialiased lines are treated as a sequence of @r{1×@var{width}}
-rectangles for purposes of stippling. Whether rectangle @r{@var{s}} is
+rectangles for purposes of stippling. Whether rectangle @r{@var{s}} is
rasterized or not depends on the fragment rule described for aliased
lines, counting rectangles rather than groups of fragments.
To enable and disable line stippling, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_LINE_STIPPLE}. When enabled, the
-line stipple pattern is applied as described above. When disabled, it is
-as if the pattern were all 1's. Initially, line stippling is disabled.
+@code{glDisable} with argument @code{GL_LINE_STIPPLE}. When enabled,
+the line stipple pattern is applied as described above. When disabled,
+it is as if the pattern were all 1's. Initially, line stippling is
+disabled.
@code{GL_INVALID_OPERATION} is generated if @code{glLineStipple} is
executed between the execution of @code{glBegin} and the corresponding
@table @asis
@item @var{width}
-Specifies the width of rasterized lines. The initial value is 1.
+Specifies the width of rasterized lines. The initial value is 1.
@end table
@code{glLineWidth} specifies the rasterized width of both aliased and
-antialiased lines. Using a line width other than 1 has different
-effects, depending on whether line antialiasing is enabled. To enable
+antialiased lines. Using a line width other than 1 has different
+effects, depending on whether line antialiasing is enabled. To enable
and disable line antialiasing, call @code{glEnable} and @code{glDisable}
-with argument @code{GL_LINE_SMOOTH}. Line antialiasing is initially
+with argument @code{GL_LINE_SMOOTH}. Line antialiasing is initially
disabled.
If line antialiasing is disabled, the actual width is determined by
-rounding the supplied width to the nearest integer. (If the rounding
+rounding the supplied width to the nearest integer. (If the rounding
results in the value 0, it is as if the line width were 1.) If
@r{∣Δ@var{x},∣>=∣Δ@var{y},∣}, @var{i} pixels are filled in each column
that is rasterized, where @var{i} is the rounded value of @var{width}.
If antialiasing is enabled, line rasterization produces a fragment for
each pixel square that intersects the region lying within the rectangle
having width equal to the current line width, length equal to the actual
-length of the line, and centered on the mathematical line segment. The
+length of the line, and centered on the mathematical line segment. The
coverage value for each fragment is the window coordinate area of the
intersection of the rectangular region with the corresponding pixel
-square. This value is saved and used in the final rasterization step.
+square. This value is saved and used in the final rasterization step.
-Not all widths can be supported when line antialiasing is enabled. If an
-unsupported width is requested, the nearest supported width is used.
+Not all widths can be supported when line antialiasing is enabled. If
+an unsupported width is requested, the nearest supported width is used.
Only width 1 is guaranteed to be supported; others depend on the
-implementation. Likewise, there is a range for aliased line widths as
-well. To query the range of supported widths and the size difference
+implementation. Likewise, there is a range for aliased line widths as
+well. To query the range of supported widths and the size difference
between supported widths within the range, call @code{glGet} with
arguments @code{GL_ALIASED_LINE_WIDTH_RANGE},
@code{GL_SMOOTH_LINE_WIDTH_RANGE}, and
@end table
@code{glLinkProgram} links the program object specified by
-@var{program}. If any shader objects of type @code{GL_VERTEX_SHADER} are
-attached to @var{program}, they will be used to create an executable
-that will run on the programmable vertex processor. If any shader
+@var{program}. If any shader objects of type @code{GL_VERTEX_SHADER}
+are attached to @var{program}, they will be used to create an executable
+that will run on the programmable vertex processor. If any shader
objects of type @code{GL_FRAGMENT_SHADER} are attached to @var{program},
they will be used to create an executable that will run on the
programmable fragment processor.
The status of the link operation will be stored as part of the program
-object's state. This value will be set to @code{GL_TRUE} if the program
+object's state. This value will be set to @code{GL_TRUE} if the program
object was linked without errors and is ready for use, and
-@code{GL_FALSE} otherwise. It can be queried by calling
+@code{GL_FALSE} otherwise. It can be queried by calling
@code{glGetProgram} with arguments @var{program} and
@code{GL_LINK_STATUS}.
uniform variables belonging to @var{program} will be initialized to 0,
and each of the program object's active uniform variables will be
assigned a location that can be queried by calling
-@code{glGetUniformLocation}. Also, any active user-defined attribute
+@code{glGetUniformLocation}. Also, any active user-defined attribute
variables that have not been bound to a generic vertex attribute index
will be bound to one at this time.
Linking of a program object can fail for a number of reasons as
-specified in the @var{OpenGL Shading Language Specification}. The
+specified in the @var{OpenGL Shading Language Specification}. The
following lists some of the conditions that will cause a link error.
@itemize
When a program object has been successfully linked, the program object
can be made part of current state by calling @code{glUseProgram}.
Whether or not the link operation was successful, the program object's
-information log will be overwritten. The information log can be
+information log will be overwritten. The information log can be
retrieved by calling @code{glGetProgramInfoLog}.
@code{glLinkProgram} will also install the generated executables as part
of the current rendering state if the link operation was successful and
the specified program object is already currently in use as a result of
-a previous call to @code{glUseProgram}. If the program object currently
+a previous call to @code{glUseProgram}. If the program object currently
in use is relinked unsuccessfully, its link status will be set to
@code{GL_FALSE} , but the executables and associated state will remain
part of the current state until a subsequent call to @code{glUseProgram}
-removes it from use. After it is removed from use, it cannot be made
+removes it from use. After it is removed from use, it cannot be made
part of current state until it has been successfully relinked.
If @var{program} contains shader objects of type @code{GL_VERTEX_SHADER}
but does not contain shader objects of type @code{GL_FRAGMENT_SHADER},
the vertex shader will be linked against the implicit interface for
-fixed functionality fragment processing. Similarly, if @var{program}
+fixed functionality fragment processing. Similarly, if @var{program}
contains shader objects of type @code{GL_FRAGMENT_SHADER} but it does
not contain shader objects of type @code{GL_VERTEX_SHADER}, the fragment
shader will be linked against the implicit interface for fixed
functionality vertex processing.
The program object's information log is updated and the program is
-generated at the time of the link operation. After the link operation,
+generated at the time of the link operation. After the link operation,
applications are free to modify attached shader objects, compile
attached shader objects, detach shader objects, delete shader objects,
-and attach additional shader objects. None of these operations affects
+and attach additional shader objects. None of these operations affects
the information log or the program that is part of the program object.
@code{GL_INVALID_VALUE} is generated if @var{program} is not a value
@table @asis
@item @var{base}
Specifies an integer offset that will be added to @code{glCallLists}
-offsets to generate display-list names. The initial value is 0.
+offsets to generate display-list names. The initial value is 0.
@end table
-@code{glCallLists} specifies an array of offsets. Display-list names are
-generated by adding @var{base} to each offset. Names that reference
+@code{glCallLists} specifies an array of offsets. Display-list names
+are generated by adding @var{base} to each offset. Names that reference
valid display lists are executed; the others are ignored.
@code{GL_INVALID_OPERATION} is generated if @code{glListBase} is
Replace the current matrix with the identity matrix.
@code{glLoadIdentity} replaces the current matrix with the identity
-matrix. It is semantically equivalent to calling @code{glLoadMatrix}
+matrix. It is semantically equivalent to calling @code{glLoadMatrix}
with the identity matrix
@end table
@code{glLoadMatrix} replaces the current matrix with the one whose
-elements are specified by @var{m}. The current matrix is the projection
+elements are specified by @var{m}. The current matrix is the projection
matrix, modelview matrix, or texture matrix, depending on the current
matrix mode (see @code{glMatrixMode}).
-The current matrix, M, defines a transformation of coordinates. For
-instance, assume M refers to the modelview matrix. If
+The current matrix, M, defines a transformation of coordinates. For
+instance, assume M refers to the modelview matrix. If
@r{@var{v}=(@var{v}[0,],@var{v}[1,]@var{v}[2,]@var{v}[3,])} is the
set of object coordinates of a vertex, and @var{m} points to an array of
@r{16} single- or double-precision floating-point values
@end table
The name stack is used during selection mode to allow sets of rendering
-commands to be uniquely identified. It consists of an ordered set of
+commands to be uniquely identified. It consists of an ordered set of
unsigned integers and is initially empty.
@code{glLoadName} causes @var{name} to replace the value on the top of
the name stack.
The name stack is always empty while the render mode is not
-@code{GL_SELECT}. Calls to @code{glLoadName} while the render mode is
+@code{GL_SELECT}. Calls to @code{glLoadName} while the render mode is
not @code{GL_SELECT} are ignored.
@code{GL_INVALID_OPERATION} is generated if @code{glLoadName} is called
@end table
@code{glLoadTransposeMatrix} replaces the current matrix with the one
-whose elements are specified by @var{m}. The current matrix is the
+whose elements are specified by @var{m}. The current matrix is the
projection matrix, modelview matrix, or texture matrix, depending on the
current matrix mode (see @code{glMatrixMode}).
-The current matrix, M, defines a transformation of coordinates. For
-instance, assume M refers to the modelview matrix. If
+The current matrix, M, defines a transformation of coordinates. For
+instance, assume M refers to the modelview matrix. If
@r{@var{v}=(@var{v}[0,],@var{v}[1,]@var{v}[2,]@var{v}[3,])} is the
set of object coordinates of a vertex, and @var{m} points to an array of
@r{16} single- or double-precision floating-point values
@table @asis
@item @var{opcode}
-Specifies a symbolic constant that selects a logical operation. The
+Specifies a symbolic constant that selects a logical operation. The
following symbols are accepted: @code{GL_CLEAR}, @code{GL_SET},
@code{GL_COPY}, @code{GL_COPY_INVERTED}, @code{GL_NOOP},
@code{GL_INVERT}, @code{GL_AND}, @code{GL_NAND}, @code{GL_OR},
index or RGBA color at the corresponding location in the frame buffer.
To enable or disable the logical operation, call @code{glEnable} and
@code{glDisable} using the symbolic constant @code{GL_COLOR_LOGIC_OP}
-for RGBA mode or @code{GL_INDEX_LOGIC_OP} for color index mode. The
+for RGBA mode or @code{GL_INDEX_LOGIC_OP} for color index mode. The
initial value is disabled for both operations.
@end table
-@var{opcode} is a symbolic constant chosen from the list above. In the
+@var{opcode} is a symbolic constant chosen from the list above. In the
explanation of the logical operations, @var{s} represents the incoming
color index and @var{d} represents the index in the frame buffer.
-Standard C-language operators are used. As these bitwise operators
+Standard C-language operators are used. As these bitwise operators
suggest, the logical operation is applied independently to each bit pair
of the source and destination indices or colors.
@item @var{stride}
Specifies the number of floats or doubles between the beginning of one
control point and the beginning of the next one in the data structure
-referenced in @var{points}. This allows control points to be embedded in
-arbitrary data structures. The only constraint is that the values for a
-particular control point must occupy contiguous memory locations.
+referenced in @var{points}. This allows control points to be embedded
+in arbitrary data structures. The only constraint is that the values
+for a particular control point must occupy contiguous memory locations.
@item @var{order}
-Specifies the number of control points. Must be positive.
+Specifies the number of control points. Must be positive.
@item @var{points}
Specifies a pointer to the array of control points.
All polynomial or rational polynomial splines of any degree (up to the
maximum degree supported by the GL implementation) can be described
-using evaluators. These include almost all splines used in computer
+using evaluators. These include almost all splines used in computer
graphics: B-splines, Bezier curves, Hermite splines, and so on.
-Evaluators define curves based on Bernstein polynomials. Define
+Evaluators define curves based on Bernstein polynomials. Define
@r{@var{p}(@var{u}^,)} as
@r{@var{p}(@var{u}^,)=Σ@var{i}=0@var{n}@var{B}_@var{i},^@var{n}(@var{u}^,)@var{R}_@var{i}}
@r{0^0==1} and @r{((@var{n}), (0),,)==1}
@code{glMap1} is used to define the basis and to specify what kind of
-values are produced. Once defined, a map can be enabled and disabled by
+values are produced. Once defined, a map can be enabled and disabled by
calling @code{glEnable} and @code{glDisable} with the map name, one of
the nine predefined values for @var{target} described below.
@code{glEvalCoord1} evaluates the one-dimensional maps that are enabled.
@var{target} is a symbolic constant that indicates what kind of control
points are provided in @var{points}, and what output is generated when
-the map is evaluated. It can assume one of nine predefined values:
+the map is evaluated. It can assume one of nine predefined values:
@table @asis
@item @code{GL_MAP1_VERTEX_3}
Each control point is three floating-point values representing
-@r{@var{x}}, @r{@var{y}}, and @r{@var{z}}. Internal @code{glVertex3}
+@r{@var{x}}, @r{@var{y}}, and @r{@var{z}}. Internal @code{glVertex3}
commands are generated when the map is evaluated.
@item @code{GL_MAP1_VERTEX_4}
Each control point is four floating-point values representing
-@r{@var{x}}, @r{@var{y}}, @r{@var{z}}, and @r{@var{w}}. Internal
+@r{@var{x}}, @r{@var{y}}, @r{@var{z}}, and @r{@var{w}}. Internal
@code{glVertex4} commands are generated when the map is evaluated.
@item @code{GL_MAP1_INDEX}
Each control point is a single floating-point value representing a color
-index. Internal @code{glIndex} commands are generated when the map is
+index. Internal @code{glIndex} commands are generated when the map is
evaluated but the current index is not updated with the value of these
@code{glIndex} commands.
@item @code{GL_MAP1_COLOR_4}
Each control point is four floating-point values representing red,
-green, blue, and alpha. Internal @code{glColor4} commands are generated
+green, blue, and alpha. Internal @code{glColor4} commands are generated
when the map is evaluated but the current color is not updated with the
value of these @code{glColor4} commands.
@item @code{GL_MAP1_TEXTURE_COORD_1}
Each control point is a single floating-point value representing the
-@r{@var{s}} texture coordinate. Internal @code{glTexCoord1} commands are
-generated when the map is evaluated but the current texture coordinates
-are not updated with the value of these @code{glTexCoord} commands.
+@r{@var{s}} texture coordinate. Internal @code{glTexCoord1} commands
+are generated when the map is evaluated but the current texture
+coordinates are not updated with the value of these @code{glTexCoord}
+commands.
@item @code{GL_MAP1_TEXTURE_COORD_2}
Each control point is two floating-point values representing the
-@r{@var{s}} and @r{@var{t}} texture coordinates. Internal
+@r{@var{s}} and @r{@var{t}} texture coordinates. Internal
@code{glTexCoord2} commands are generated when the map is evaluated but
the current texture coordinates are not updated with the value of these
@code{glTexCoord} commands.
@item @code{GL_MAP1_TEXTURE_COORD_3}
Each control point is three floating-point values representing the
-@r{@var{s}}, @r{@var{t}}, and @r{@var{r}} texture coordinates. Internal
+@r{@var{s}}, @r{@var{t}}, and @r{@var{r}} texture coordinates. Internal
@code{glTexCoord3} commands are generated when the map is evaluated but
the current texture coordinates are not updated with the value of these
@code{glTexCoord} commands.
@item @code{GL_MAP1_TEXTURE_COORD_4}
Each control point is four floating-point values representing the
@r{@var{s}}, @r{@var{t}}, @r{@var{r}}, and @r{@var{q}} texture
-coordinates. Internal @code{glTexCoord4} commands are generated when the
-map is evaluated but the current texture coordinates are not updated
+coordinates. Internal @code{glTexCoord4} commands are generated when
+the map is evaluated but the current texture coordinates are not updated
with the value of these @code{glTexCoord} commands.
@end table
@var{stride}, @var{order}, and @var{points} define the array addressing
-for accessing the control points. @var{points} is the location of the
+for accessing the control points. @var{points} is the location of the
first control point, which occupies one, two, three, or four contiguous
-memory locations, depending on which map is being defined. @var{order}
-is the number of control points in the array. @var{stride} specifies how
-many float or double locations to advance the internal memory pointer to
-reach the next control point.
+memory locations, depending on which map is being defined. @var{order}
+is the number of control points in the array. @var{stride} specifies
+how many float or double locations to advance the internal memory
+pointer to reach the next control point.
@code{GL_INVALID_ENUM} is generated if @var{target} is not an accepted
value.
@itemx @var{u2}
Specify a linear mapping of @r{@var{u}}, as presented to
@code{glEvalCoord2}, to @r{@var{u}^}, one of the two variables that are
-evaluated by the equations specified by this command. Initially,
+evaluated by the equations specified by this command. Initially,
@var{u1} is 0 and @var{u2} is 1.
@item @var{ustride}
the @r{@var{u}} and @r{@var{v}} control point indices, respectively.
This allows control points to be embedded in arbitrary data structures.
The only constraint is that the values for a particular control point
-must occupy contiguous memory locations. The initial value of
+must occupy contiguous memory locations. The initial value of
@var{ustride} is 0.
@item @var{uorder}
Specifies the dimension of the control point array in the @r{@var{u}}
-axis. Must be positive. The initial value is 1.
+axis. Must be positive. The initial value is 1.
@item @var{v1}
@itemx @var{v2}
Specify a linear mapping of @r{@var{v}}, as presented to
@code{glEvalCoord2}, to @r{@var{v}^}, one of the two variables that are
-evaluated by the equations specified by this command. Initially,
+evaluated by the equations specified by this command. Initially,
@var{v1} is 0 and @var{v2} is 1.
@item @var{vstride}
the @r{@var{u}} and @r{@var{v}} control point indices, respectively.
This allows control points to be embedded in arbitrary data structures.
The only constraint is that the values for a particular control point
-must occupy contiguous memory locations. The initial value of
+must occupy contiguous memory locations. The initial value of
@var{vstride} is 0.
@item @var{vorder}
Specifies the dimension of the control point array in the @r{@var{v}}
-axis. Must be positive. The initial value is 1.
+axis. Must be positive. The initial value is 1.
@item @var{points}
Specifies a pointer to the array of control points.
All polynomial or rational polynomial splines of any degree (up to the
maximum degree supported by the GL implementation) can be described
-using evaluators. These include almost all surfaces used in computer
+using evaluators. These include almost all surfaces used in computer
graphics, including B-spline surfaces, NURBS surfaces, Bezier surfaces,
and so on.
Recall that @r{0^0==1} and @r{((@var{n}), (0),,)==1}
@code{glMap2} is used to define the basis and to specify what kind of
-values are produced. Once defined, a map can be enabled and disabled by
+values are produced. Once defined, a map can be enabled and disabled by
calling @code{glEnable} and @code{glDisable} with the map name, one of
-the nine predefined values for @var{target}, described below. When
+the nine predefined values for @var{target}, described below. When
@code{glEvalCoord2} presents values @r{@var{u}} and @r{@var{v}}, the
bivariate Bernstein polynomials are evaluated using @r{@var{u}^} and
@r{@var{v}^}, where
@var{target} is a symbolic constant that indicates what kind of control
points are provided in @var{points}, and what output is generated when
-the map is evaluated. It can assume one of nine predefined values:
+the map is evaluated. It can assume one of nine predefined values:
@table @asis
@item @code{GL_MAP2_VERTEX_3}
Each control point is three floating-point values representing
-@r{@var{x}}, @r{@var{y}}, and @r{@var{z}}. Internal @code{glVertex3}
+@r{@var{x}}, @r{@var{y}}, and @r{@var{z}}. Internal @code{glVertex3}
commands are generated when the map is evaluated.
@item @code{GL_MAP2_VERTEX_4}
Each control point is four floating-point values representing
-@r{@var{x}}, @r{@var{y}}, @r{@var{z}}, and @r{@var{w}}. Internal
+@r{@var{x}}, @r{@var{y}}, @r{@var{z}}, and @r{@var{w}}. Internal
@code{glVertex4} commands are generated when the map is evaluated.
@item @code{GL_MAP2_INDEX}
Each control point is a single floating-point value representing a color
-index. Internal @code{glIndex} commands are generated when the map is
+index. Internal @code{glIndex} commands are generated when the map is
evaluated but the current index is not updated with the value of these
@code{glIndex} commands.
@item @code{GL_MAP2_COLOR_4}
Each control point is four floating-point values representing red,
-green, blue, and alpha. Internal @code{glColor4} commands are generated
+green, blue, and alpha. Internal @code{glColor4} commands are generated
when the map is evaluated but the current color is not updated with the
value of these @code{glColor4} commands.
@item @code{GL_MAP2_TEXTURE_COORD_1}
Each control point is a single floating-point value representing the
-@r{@var{s}} texture coordinate. Internal @code{glTexCoord1} commands are
-generated when the map is evaluated but the current texture coordinates
-are not updated with the value of these @code{glTexCoord} commands.
+@r{@var{s}} texture coordinate. Internal @code{glTexCoord1} commands
+are generated when the map is evaluated but the current texture
+coordinates are not updated with the value of these @code{glTexCoord}
+commands.
@item @code{GL_MAP2_TEXTURE_COORD_2}
Each control point is two floating-point values representing the
-@r{@var{s}} and @r{@var{t}} texture coordinates. Internal
+@r{@var{s}} and @r{@var{t}} texture coordinates. Internal
@code{glTexCoord2} commands are generated when the map is evaluated but
the current texture coordinates are not updated with the value of these
@code{glTexCoord} commands.
@item @code{GL_MAP2_TEXTURE_COORD_3}
Each control point is three floating-point values representing the
-@r{@var{s}}, @r{@var{t}}, and @r{@var{r}} texture coordinates. Internal
+@r{@var{s}}, @r{@var{t}}, and @r{@var{r}} texture coordinates. Internal
@code{glTexCoord3} commands are generated when the map is evaluated but
the current texture coordinates are not updated with the value of these
@code{glTexCoord} commands.
@item @code{GL_MAP2_TEXTURE_COORD_4}
Each control point is four floating-point values representing the
@r{@var{s}}, @r{@var{t}}, @r{@var{r}}, and @r{@var{q}} texture
-coordinates. Internal @code{glTexCoord4} commands are generated when the
-map is evaluated but the current texture coordinates are not updated
+coordinates. Internal @code{glTexCoord4} commands are generated when
+the map is evaluated but the current texture coordinates are not updated
with the value of these @code{glTexCoord} commands.
@end table
@var{ustride}, @var{uorder}, @var{vstride}, @var{vorder}, and
@var{points} define the array addressing for accessing the control
-points. @var{points} is the location of the first control point, which
+points. @var{points} is the location of the first control point, which
occupies one, two, three, or four contiguous memory locations, depending
-on which map is being defined. There are @r{@var{uorder}×@var{vorder}}
-control points in the array. @var{ustride} specifies how many float or
+on which map is being defined. There are @r{@var{uorder}×@var{vorder}}
+control points in the array. @var{ustride} specifies how many float or
double locations are skipped to advance the internal memory pointer from
control point @r{@var{R}_@var{i}@var{j},} to control point
-@r{@var{R}_(@var{i}+1,)@var{j},}. @var{vstride} specifies how many
+@r{@var{R}_(@var{i}+1,)@var{j},}. @var{vstride} specifies how many
float or double locations are skipped to advance the internal memory
pointer from control point @r{@var{R}_@var{i}@var{j},} to control point
@r{@var{R}_@var{i}(@var{j}+1,),}.
@table @asis
@item @var{target}
-Specifies the target buffer object being mapped. The symbolic constant
+Specifies the target buffer object being mapped. The symbolic constant
must be @code{GL_ARRAY_BUFFER}, @code{GL_ELEMENT_ARRAY_BUFFER},
@code{GL_PIXEL_PACK_BUFFER}, or @code{GL_PIXEL_UNPACK_BUFFER}.
@item @var{access}
Specifies the access policy, indicating whether it will be possible to
read from, write to, or both read from and write to the buffer object's
-mapped data store. The symbolic constant must be @code{GL_READ_ONLY},
+mapped data store. The symbolic constant must be @code{GL_READ_ONLY},
@code{GL_WRITE_ONLY}, or @code{GL_READ_WRITE}.
@end table
@code{glMapBuffer} maps to the client's address space the entire data
-store of the buffer object currently bound to @var{target}. The data can
-then be directly read and/or written relative to the returned pointer,
-depending on the specified @var{access} policy. If the GL is unable to
-map the buffer object's data store, @code{glMapBuffer} generates an
-error and returns @code{NULL}. This may occur for system-specific
-reasons, such as low virtual memory availability.
+store of the buffer object currently bound to @var{target}. The data
+can then be directly read and/or written relative to the returned
+pointer, depending on the specified @var{access} policy. If the GL is
+unable to map the buffer object's data store, @code{glMapBuffer}
+generates an error and returns @code{NULL}. This may occur for
+system-specific reasons, such as low virtual memory availability.
If a mapped data store is accessed in a way inconsistent with the
specified @var{access} policy, no error is generated, but performance
may be negatively impacted and system errors, including program
-termination, may result. Unlike the @var{usage} parameter of
+termination, may result. Unlike the @var{usage} parameter of
@code{glBufferData}, @var{access} is not a hint, and does in fact
constrain the usage of the mapped data store on some GL implementations.
In order to achieve the highest performance available, a buffer object's
@var{usage} and @var{access} parameters.
A mapped data store must be unmapped with @code{glUnmapBuffer} before
-its buffer object is used. Otherwise an error will be generated by any
+its buffer object is used. Otherwise an error will be generated by any
GL command that attempts to dereference the buffer object's data store.
When a data store is unmapped, the pointer to its data store becomes
-invalid. @code{glUnmapBuffer} returns @code{GL_TRUE} unless the data
+invalid. @code{glUnmapBuffer} returns @code{GL_TRUE} unless the data
store contents have become corrupt during the time the data store was
-mapped. This can occur for system-specific reasons that affect the
-availability of graphics memory, such as screen mode changes. In such
+mapped. This can occur for system-specific reasons that affect the
+availability of graphics memory, such as screen mode changes. In such
situations, @code{GL_FALSE} is returned and the data store contents are
-undefined. An application must detect this rare condition and
+undefined. An application must detect this rare condition and
reinitialize the data store.
A buffer object's mapped data store is automatically unmapped when the
@code{GL_READ_ONLY}, @code{GL_WRITE_ONLY}, or @code{GL_READ_WRITE}.
@code{GL_OUT_OF_MEMORY} is generated when @code{glMapBuffer} is executed
-if the GL is unable to map the buffer object's data store. This may
+if the GL is unable to map the buffer object's data store. This may
occur for a variety of system-specific reasons, such as the absence of
sufficient remaining virtual memory.
@table @asis
@item @var{un}
Specifies the number of partitions in the grid range interval [@var{u1},
-@var{u2}]. Must be positive.
+@var{u2}]. Must be positive.
@item @var{u1}
@itemx @var{u2}
@code{glMapGrid1} and @code{glMapGrid2} specify the linear grid mappings
between the @r{@var{i}} (or @r{@var{i}} and @r{@var{j}}) integer grid
coordinates, to the @r{@var{u}} (or @r{@var{u}} and @r{@var{v}})
-floating-point evaluation map coordinates. See @code{glMap1} and
+floating-point evaluation map coordinates. See @code{glMap1} and
@code{glMap2} for details of how @r{@var{u}} and @r{@var{v}} coordinates
are evaluated.
@code{glMapGrid1} specifies a single linear mapping such that integer
grid coordinate 0 maps exactly to @var{u1}, and integer grid coordinate
-@var{un} maps exactly to @var{u2}. All other integer grid coordinates
+@var{un} maps exactly to @var{u2}. All other integer grid coordinates
@r{@var{i}} are mapped so that
@r{@var{u}=@var{i}(@var{u2}-@var{u1},)/@var{un}+@var{u1}}
-@code{glMapGrid2} specifies two such linear mappings. One maps integer
+@code{glMapGrid2} specifies two such linear mappings. One maps integer
grid coordinate @r{@var{i}=0} exactly to @var{u1}, and integer grid
-coordinate @r{@var{i}=@var{un}} exactly to @var{u2}. The other maps
+coordinate @r{@var{i}=@var{un}} exactly to @var{u2}. The other maps
integer grid coordinate @r{@var{j}=0} exactly to @var{v1}, and integer
-grid coordinate @r{@var{j}=@var{vn}} exactly to @var{v2}. Other integer
+grid coordinate @r{@var{j}=@var{vn}} exactly to @var{v2}. Other integer
grid coordinates @r{@var{i}} and @r{@var{j}} are mapped such that
@r{@var{u}=@var{i}(@var{u2}-@var{u1},)/@var{un}+@var{u1}}
@table @asis
@item @var{face}
-Specifies which face or faces are being updated. Must be one of
+Specifies which face or faces are being updated. Must be one of
@code{GL_FRONT}, @code{GL_BACK}, or @code{GL_FRONT_AND_BACK}.
@item @var{pname}
Specifies the single-valued material parameter of the face or faces that
-is being updated. Must be @code{GL_SHININESS}.
+is being updated. Must be @code{GL_SHININESS}.
@item @var{param}
Specifies the value that parameter @code{GL_SHININESS} will be set to.
@end table
-@code{glMaterial} assigns values to material parameters. There are two
-matched sets of material parameters. One, the @var{front-facing} set, is
-used to shade points, lines, bitmaps, and all polygons (when two-sided
-lighting is disabled), or just front-facing polygons (when two-sided
-lighting is enabled). The other set, @var{back-facing}, is used to shade
-back-facing polygons only when two-sided lighting is enabled. Refer to
-the @code{glLightModel} reference page for details concerning one- and
-two-sided lighting calculations.
+@code{glMaterial} assigns values to material parameters. There are two
+matched sets of material parameters. One, the @var{front-facing} set,
+is used to shade points, lines, bitmaps, and all polygons (when
+two-sided lighting is disabled), or just front-facing polygons (when
+two-sided lighting is enabled). The other set, @var{back-facing}, is
+used to shade back-facing polygons only when two-sided lighting is
+enabled. Refer to the @code{glLightModel} reference page for details
+concerning one- and two-sided lighting calculations.
-@code{glMaterial} takes three arguments. The first, @var{face},
+@code{glMaterial} takes three arguments. The first, @var{face},
specifies whether the @code{GL_FRONT} materials, the @code{GL_BACK}
materials, or both @code{GL_FRONT_AND_BACK} materials will be modified.
The second, @var{pname}, specifies which of several parameters in one or
-both sets will be modified. The third, @var{params}, specifies what
+both sets will be modified. The third, @var{params}, specifies what
value or values will be assigned to the specified parameter.
Material parameters are used in the lighting equation that is optionally
-applied to each vertex. The equation is discussed in the
-@code{glLightModel} reference page. The parameters that can be specified
-using @code{glMaterial}, and their interpretations by the lighting
-equation, are as follows:
+applied to each vertex. The equation is discussed in the
+@code{glLightModel} reference page. The parameters that can be
+specified using @code{glMaterial}, and their interpretations by the
+lighting equation, are as follows:
@table @asis
@item @code{GL_AMBIENT}
@var{params} contains four integer or floating-point values that specify
-the ambient RGBA reflectance of the material. Integer values are mapped
+the ambient RGBA reflectance of the material. Integer values are mapped
linearly such that the most positive representable value maps to 1.0,
and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial ambient reflectance for
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial ambient reflectance for
both front- and back-facing materials is (0.2, 0.2, 0.2, 1.0).
@item @code{GL_DIFFUSE}
@var{params} contains four integer or floating-point values that specify
-the diffuse RGBA reflectance of the material. Integer values are mapped
+the diffuse RGBA reflectance of the material. Integer values are mapped
linearly such that the most positive representable value maps to 1.0,
and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial diffuse reflectance for
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial diffuse reflectance for
both front- and back-facing materials is (0.8, 0.8, 0.8, 1.0).
@item @code{GL_SPECULAR}
@var{params} contains four integer or floating-point values that specify
-the specular RGBA reflectance of the material. Integer values are mapped
-linearly such that the most positive representable value maps to 1.0,
-and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial specular reflectance for
+the specular RGBA reflectance of the material. Integer values are
+mapped linearly such that the most positive representable value maps to
+1.0, and the most negative representable value maps to @r{-1.0}.
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial specular reflectance for
both front- and back-facing materials is (0, 0, 0, 1).
@item @code{GL_EMISSION}
@var{params} contains four integer or floating-point values that specify
-the RGBA emitted light intensity of the material. Integer values are
+the RGBA emitted light intensity of the material. Integer values are
mapped linearly such that the most positive representable value maps to
1.0, and the most negative representable value maps to @r{-1.0}.
-Floating-point values are mapped directly. Neither integer nor
-floating-point values are clamped. The initial emission intensity for
+Floating-point values are mapped directly. Neither integer nor
+floating-point values are clamped. The initial emission intensity for
both front- and back-facing materials is (0, 0, 0, 1).
@item @code{GL_SHININESS}
@var{params} is a single integer or floating-point value that specifies
-the RGBA specular exponent of the material. Integer and floating-point
-values are mapped directly. Only values in the range @r{[0,128]} are
-accepted. The initial specular exponent for both front- and back-facing
+the RGBA specular exponent of the material. Integer and floating-point
+values are mapped directly. Only values in the range @r{[0,128]} are
+accepted. The initial specular exponent for both front- and back-facing
materials is 0.
@item @code{GL_AMBIENT_AND_DIFFUSE}
@item @code{GL_COLOR_INDEXES}
@var{params} contains three integer or floating-point values specifying
-the color indices for ambient, diffuse, and specular lighting. These
+the color indices for ambient, diffuse, and specular lighting. These
three values, and @code{GL_SHININESS}, are the only material values used
-by the color index mode lighting equation. Refer to the
+by the color index mode lighting equation. Refer to the
@code{glLightModel} reference page for a discussion of color index
lighting.
@table @asis
@item @var{mode}
Specifies which matrix stack is the target for subsequent matrix
-operations. Three values are accepted: @code{GL_MODELVIEW},
-@code{GL_PROJECTION}, and @code{GL_TEXTURE}. The initial value is
-@code{GL_MODELVIEW}. Additionally, if the @code{ARB_imaging} extension
+operations. Three values are accepted: @code{GL_MODELVIEW},
+@code{GL_PROJECTION}, and @code{GL_TEXTURE}. The initial value is
+@code{GL_MODELVIEW}. Additionally, if the @code{ARB_imaging} extension
is supported, @code{GL_COLOR} is also accepted.
@end table
-@code{glMatrixMode} sets the current matrix mode. @var{mode} can assume
+@code{glMatrixMode} sets the current matrix mode. @var{mode} can assume
one of four values:
@table @asis
@end table
To find out which matrix stack is currently the target of all matrix
-operations, call @code{glGet} with argument @code{GL_MATRIX_MODE}. The
+operations, call @code{glGet} with argument @code{GL_MATRIX_MODE}. The
initial value is @code{GL_MODELVIEW}.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
@table @asis
@item @var{target}
-The minmax table whose parameters are to be set. Must be
+The minmax table whose parameters are to be set. Must be
@code{GL_MINMAX}.
@item @var{internalformat}
-The format of entries in the minmax table. Must be one of
+The format of entries in the minmax table. Must be one of
@code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_LUMINANCE}, @code{GL_LUMINANCE4},
@code{GL_LUMINANCE8}, @code{GL_LUMINANCE12}, @code{GL_LUMINANCE16},
@item @var{sink}
If @code{GL_TRUE}, pixels will be consumed by the minmax process and no
-drawing or texture loading will take place. If @code{GL_FALSE}, pixels
+drawing or texture loading will take place. If @code{GL_FALSE}, pixels
will proceed to the final conversion process after minmax.
@end table
When @code{GL_MINMAX} is enabled, the RGBA components of incoming pixels
are compared to the minimum and maximum values for each component, which
-are stored in the two-element minmax table. (The first element stores
+are stored in the two-element minmax table. (The first element stores
the minima, and the second element stores the maxima.) If a pixel
component is greater than the corresponding component in the maximum
element, then the maximum element is updated with the pixel component
-value. If a pixel component is less than the corresponding component in
+value. If a pixel component is less than the corresponding component in
the minimum element, then the minimum element is updated with the pixel
-component value. (In both cases, if the internal format of the minmax
+component value. (In both cases, if the internal format of the minmax
table includes luminance, then the R color component of incoming pixels
is used for comparison.) The contents of the minmax table may be
-retrieved at a later time by calling @code{glGetMinmax}. The minmax
+retrieved at a later time by calling @code{glGetMinmax}. The minmax
operation is enabled or disabled by calling @code{glEnable} or
@code{glDisable}, respectively, with an argument of @code{GL_MINMAX}.
@code{glMinmax} redefines the current minmax table to have entries of
-the format specified by @var{internalformat}. The maximum element is
+the format specified by @var{internalformat}. The maximum element is
initialized with the smallest possible component values, and the minimum
-element is initialized with the largest possible component values. The
-values in the previous minmax table, if any, are lost. If @var{sink} is
+element is initialized with the largest possible component values. The
+values in the previous minmax table, if any, are lost. If @var{sink} is
@code{GL_TRUE}, then pixels are discarded after minmax; no further
processing of the pixels takes place, and no drawing, texture loading,
or pixel readback will result.
@table @asis
@item @var{mode}
-Specifies what kind of primitives to render. Symbolic constants
+Specifies what kind of primitives to render. Symbolic constants
@code{GL_POINTS}, @code{GL_LINE_STRIP}, @code{GL_LINE_LOOP},
@code{GL_LINES}, @code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN},
@code{GL_TRIANGLES}, @code{GL_QUAD_STRIP}, @code{GL_QUADS}, and
@end table
@code{glMultiDrawArrays} specifies multiple sets of geometric primitives
-with very few subroutine calls. Instead of calling a GL procedure to
+with very few subroutine calls. Instead of calling a GL procedure to
pass each individual vertex, normal, texture coordinate, edge flag, or
color, you can prespecify separate arrays of vertices, normals, and
colors and use them to construct a sequence of primitives with a single
When @code{glMultiDrawArrays} is called, it uses @var{count} sequential
elements from each enabled array to construct a sequence of geometric
-primitives, beginning with element @var{first}. @var{mode} specifies
+primitives, beginning with element @var{first}. @var{mode} specifies
what kind of primitives are constructed, and how the array elements
-construct those primitives. If @code{GL_VERTEX_ARRAY} is not enabled, no
-geometric primitives are generated.
+construct those primitives. If @code{GL_VERTEX_ARRAY} is not enabled,
+no geometric primitives are generated.
Vertex attributes that are modified by @code{glMultiDrawArrays} have an
-unspecified value after @code{glMultiDrawArrays} returns. For example,
+unspecified value after @code{glMultiDrawArrays} returns. For example,
if @code{GL_COLOR_ARRAY} is enabled, the value of the current color is
-undefined after @code{glMultiDrawArrays} executes. Attributes that
+undefined after @code{glMultiDrawArrays} executes. Attributes that
aren't modified remain well defined.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
@table @asis
@item @var{mode}
-Specifies what kind of primitives to render. Symbolic constants
+Specifies what kind of primitives to render. Symbolic constants
@code{GL_POINTS}, @code{GL_LINE_STRIP}, @code{GL_LINE_LOOP},
@code{GL_LINES}, @code{GL_TRIANGLE_STRIP}, @code{GL_TRIANGLE_FAN},
@code{GL_TRIANGLES}, @code{GL_QUAD_STRIP}, @code{GL_QUADS}, and
Points to an array of the elements counts.
@item @var{type}
-Specifies the type of the values in @var{indices}. Must be one of
+Specifies the type of the values in @var{indices}. Must be one of
@code{GL_UNSIGNED_BYTE}, @code{GL_UNSIGNED_SHORT}, or
@code{GL_UNSIGNED_INT}.
@end table
@code{glMultiDrawElements} specifies multiple sets of geometric
-primitives with very few subroutine calls. Instead of calling a GL
+primitives with very few subroutine calls. Instead of calling a GL
function to pass each individual vertex, normal, texture coordinate,
edge flag, or color, you can prespecify separate arrays of vertices,
normals, and so on, and use them to construct a sequence of primitives
elements are specified.
Vertex attributes that are modified by @code{glMultiDrawElements} have
-an unspecified value after @code{glMultiDrawElements} returns. For
+an unspecified value after @code{glMultiDrawElements} returns. For
example, if @code{GL_COLOR_ARRAY} is enabled, the value of the current
-color is undefined after @code{glMultiDrawElements} executes. Attributes
+color is undefined after @code{glMultiDrawElements} executes. Attributes
that aren't modified maintain their previous values.
@code{GL_INVALID_ENUM} is generated if @var{mode} is not an accepted
@table @asis
@item @var{target}
-Specifies the texture unit whose coordinates should be modified. The
+Specifies the texture unit whose coordinates should be modified. The
number of texture units is implementation dependent, but must be at
-least two. Symbolic constant must be one of
+least two. Symbolic constant must be one of
@code{GL_TEXTURE}@r{@var{i}}, where i ranges from 0 to
@code{GL_MAX_TEXTURE_COORDS} - 1, which is an implementation-dependent
value.
@itemx @var{r}
@itemx @var{q}
Specify @var{s}, @var{t}, @var{r}, and @var{q} texture coordinates for
-@var{target} texture unit. Not all parameters are present in all forms
+@var{target} texture unit. Not all parameters are present in all forms
of the command.
@end table
@code{glMultiTexCoord} specifies texture coordinates in one, two, three,
-or four dimensions. @code{glMultiTexCoord1} sets the current texture
+or four dimensions. @code{glMultiTexCoord1} sets the current texture
coordinates to @r{(@var{s},001)}; a call to @code{glMultiTexCoord2} sets
-them to @r{(@var{s},@var{t}01)}. Similarly, @code{glMultiTexCoord3}
+them to @r{(@var{s},@var{t}01)}. Similarly, @code{glMultiTexCoord3}
specifies the texture coordinates as @r{(@var{s},@var{t}@var{r}1)}, and
@code{glMultiTexCoord4} defines all four components explicitly as
@r{(@var{s},@var{t}@var{r}@var{q})}.
The current texture coordinates are part of the data that is associated
-with each vertex and with the current raster position. Initially, the
+with each vertex and with the current raster position. Initially, the
values for @r{(@var{s},@var{t}@var{r}@var{q})} are @r{(0,001)}.
using @var{m}, and replaces the current matrix with the product.
The current matrix is determined by the current matrix mode (see
-@code{glMatrixMode}). It is either the projection matrix, modelview
+@code{glMatrixMode}). It is either the projection matrix, modelview
matrix, or the texture matrix.
@code{GL_INVALID_OPERATION} is generated if @code{glMultMatrix} is
product.
The current matrix is determined by the current matrix mode (see
-@code{glMatrixMode}). It is either the projection matrix, modelview
+@code{glMatrixMode}). It is either the projection matrix, modelview
matrix, or the texture matrix.
@code{GL_INVALID_OPERATION} is generated if @code{glMultTransposeMatrix}
@end table
Display lists are groups of GL commands that have been stored for
-subsequent execution. Display lists are created with @code{glNewList}.
+subsequent execution. Display lists are created with @code{glNewList}.
All subsequent commands are placed in the display list, in the order
issued, until @code{glEndList} is called.
-@code{glNewList} has two arguments. The first argument, @var{list}, is a
-positive integer that becomes the unique name for the display list.
+@code{glNewList} has two arguments. The first argument, @var{list}, is
+a positive integer that becomes the unique name for the display list.
Names can be created and reserved with @code{glGenLists} and tested for
-uniqueness with @code{glIsList}. The second argument, @var{mode}, is a
+uniqueness with @code{glIsList}. The second argument, @var{mode}, is a
symbolic constant that can assume one of two values:
@table @asis
@end table
Certain commands are not compiled into the display list but are executed
-immediately, regardless of the display-list mode. These commands are
+immediately, regardless of the display-list mode. These commands are
@code{glAreTexturesResident}, @code{glColorPointer},
@code{glDeleteLists}, @code{glDeleteTextures},
@code{glDisableClientState}, @code{glEdgeFlagPointer},
When @code{glEndList} is encountered, the display-list definition is
completed by associating the list with the unique name @var{list}
-(specified in the @code{glNewList} command). If a display list with name
-@var{list} already exists, it is replaced only when @code{glEndList} is
-called.
+(specified in the @code{glNewList} command). If a display list with
+name @var{list} already exists, it is replaced only when
+@code{glEndList} is called.
@code{GL_INVALID_VALUE} is generated if @var{list} is 0.
the corresponding execution of @code{glEnd}.
@code{GL_OUT_OF_MEMORY} is generated if there is insufficient memory to
-compile the display list. If the GL version is 1.1 or greater, no change
-is made to the previous contents of the display list, if any, and no
-other change is made to the GL state. (It is as if no attempt had been
-made to create the new display list.)
+compile the display list. If the GL version is 1.1 or greater, no
+change is made to the previous contents of the display list, if any, and
+no other change is made to the GL state. (It is as if no attempt had
+been made to create the new display list.)
@end deftypefun
@table @asis
@item @var{type}
-Specifies the data type of each coordinate in the array. Symbolic
+Specifies the data type of each coordinate in the array. Symbolic
constants @code{GL_BYTE}, @code{GL_SHORT}, @code{GL_INT},
-@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value is
-@code{GL_FLOAT}.
+@code{GL_FLOAT}, and @code{GL_DOUBLE} are accepted. The initial value
+is @code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive normals. If @var{stride}
-is 0, the normals are understood to be tightly packed in the array. The
+Specifies the byte offset between consecutive normals. If @var{stride}
+is 0, the normals are understood to be tightly packed in the array. The
initial value is 0.
@item @var{pointer}
Specifies a pointer to the first coordinate of the first normal in the
-array. The initial value is 0.
+array. The initial value is 0.
@end table
@code{glNormalPointer} specifies the location and data format of an
-array of normals to use when rendering. @var{type} specifies the data
+array of normals to use when rendering. @var{type} specifies the data
type of each normal coordinate, and @var{stride} specifies the byte
stride from one normal to the next, allowing vertices and attributes to
be packed into a single array or stored in separate arrays.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a normal array is specified,
@var{pointer} is treated as a byte offset into the buffer object's data
-store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
+store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
is saved as normal vertex array client-side state
(@code{GL_NORMAL_ARRAY_BUFFER_BINDING}).
To enable and disable the normal array, call @code{glEnableClientState}
and @code{glDisableClientState} with the argument
-@code{GL_NORMAL_ARRAY}. If enabled, the normal array is used when
+@code{GL_NORMAL_ARRAY}. If enabled, the normal array is used when
@code{glDrawArrays}, @code{glMultiDrawArrays}, @code{glDrawElements},
@code{glMultiDrawElements}, @code{glDrawRangeElements}, or
@code{glArrayElement} is called.
@itemx @var{ny}
@itemx @var{nz}
Specify the @r{@var{x}}, @r{@var{y}}, and @r{@var{z}} coordinates of the
-new current normal. The initial value of the current normal is the unit
+new current normal. The initial value of the current normal is the unit
vector, (0, 0, 1).
@end table
The current normal is set to the given coordinates whenever
-@code{glNormal} is issued. Byte, short, or integer arguments are
+@code{glNormal} is issued. Byte, short, or integer arguments are
converted to floating-point format with a linear mapping that maps the
most positive representable integer value to 1.0 and the most negative
representable integer value to @r{-1.0}.
-Normals specified with @code{glNormal} need not have unit length. If
+Normals specified with @code{glNormal} need not have unit length. If
@code{GL_NORMALIZE} is enabled, then normals of any length specified
-with @code{glNormal} are normalized after transformation. If
+with @code{glNormal} are normalized after transformation. If
@code{GL_RESCALE_NORMAL} is enabled, normals are scaled by a scaling
-factor derived from the modelview matrix. @code{GL_RESCALE_NORMAL}
+factor derived from the modelview matrix. @code{GL_RESCALE_NORMAL}
requires that the originally specified normals were of unit length, and
that the modelview matrix contain only uniform scales for proper
-results. To enable and disable normalization, call @code{glEnable} and
+results. To enable and disable normalization, call @code{glEnable} and
@code{glDisable} with either @code{GL_NORMALIZE} or
-@code{GL_RESCALE_NORMAL}. Normalization is initially disabled.
+@code{GL_RESCALE_NORMAL}. Normalization is initially disabled.
@end deftypefun
@end table
@code{glOrtho} describes a transformation that produces a parallel
-projection. The current matrix (see @code{glMatrixMode}) is multiplied
+projection. The current matrix (see @code{glMatrixMode}) is multiplied
by this matrix and the result replaces the current matrix, as if
@code{glMultMatrix} were called with the following matrix as its
argument:
@r{(@var{right},@var{top}-@var{nearVal})} specify the points on the near
clipping plane that are mapped to the lower left and upper right corners
of the window, respectively, assuming that the eye is located at (0, 0,
-0). @r{-@var{farVal}} specifies the location of the far clipping plane.
+0). @r{-@var{farVal}} specifies the location of the far clipping plane.
Both @var{nearVal} and @var{farVal} can be either positive or negative.
Use @code{glPushMatrix} and @code{glPopMatrix} to save and restore the
-Feedback is a GL render mode. The mode is selected by calling
-@code{glRenderMode} with @code{GL_FEEDBACK}. When the GL is in feedback
-mode, no pixels are produced by rasterization. Instead, information
+Feedback is a GL render mode. The mode is selected by calling
+@code{glRenderMode} with @code{GL_FEEDBACK}. When the GL is in feedback
+mode, no pixels are produced by rasterization. Instead, information
about primitives that would have been rasterized is fed back to the
-application using the GL. See the @code{glFeedbackBuffer} reference page
-for a description of the feedback buffer and the values in it.
+application using the GL. See the @code{glFeedbackBuffer} reference
+page for a description of the feedback buffer and the values in it.
@code{glPassThrough} inserts a user-defined marker in the feedback
-buffer when it is executed in feedback mode. @var{token} is returned as
+buffer when it is executed in feedback mode. @var{token} is returned as
if it were a primitive; it is indicated with its own unique identifying
-value: @code{GL_PASS_THROUGH_TOKEN}. The order of @code{glPassThrough}
+value: @code{GL_PASS_THROUGH_TOKEN}. The order of @code{glPassThrough}
commands with respect to the specification of graphics primitives is
maintained.
@table @asis
@item @var{map}
-Specifies a symbolic map name. Must be one of the following:
+Specifies a symbolic map name. Must be one of the following:
@code{GL_PIXEL_MAP_I_TO_I}, @code{GL_PIXEL_MAP_S_TO_S},
@code{GL_PIXEL_MAP_I_TO_R}, @code{GL_PIXEL_MAP_I_TO_G},
@code{GL_PIXEL_MAP_I_TO_B}, @code{GL_PIXEL_MAP_I_TO_A},
@code{glCopyTexSubImage3D}, @code{glDrawPixels}, @code{glReadPixels},
@code{glTexImage1D}, @code{glTexImage2D}, @code{glTexImage3D},
@code{glTexSubImage1D}, @code{glTexSubImage2D}, and
-@code{glTexSubImage3D}. Additionally, if the @code{ARB_imaging} subset
+@code{glTexSubImage3D}. Additionally, if the @code{ARB_imaging} subset
is supported, the routines @code{glColorTable}, @code{glColorSubTable},
@code{glConvolutionFilter1D}, @code{glConvolutionFilter2D},
-@code{glHistogram}, @code{glMinmax}, and @code{glSeparableFilter2D}. Use
+@code{glHistogram}, @code{glMinmax}, and @code{glSeparableFilter2D}. Use
of these maps is described completely in the @code{glPixelTransfer}
reference page, and partly in the reference pages for the pixel and
-texture image commands. Only the specification of the maps is described
+texture image commands. Only the specification of the maps is described
in this reference page.
@var{map} is a symbolic map name, indicating one of ten maps to set.
@end table
The entries in a map can be specified as single-precision floating-point
-numbers, unsigned short integers, or unsigned int integers. Maps that
+numbers, unsigned short integers, or unsigned int integers. Maps that
store color component values (all but @code{GL_PIXEL_MAP_I_TO_I} and
@code{GL_PIXEL_MAP_S_TO_S}) retain their values in floating-point
-format, with unspecified mantissa and exponent sizes. Floating-point
+format, with unspecified mantissa and exponent sizes. Floating-point
values specified by @code{glPixelMapfv} are converted directly to the
internal floating-point format of these maps, then clamped to the range
-[0,1]. Unsigned integer values specified by @code{glPixelMapusv} and
+[0,1]. Unsigned integer values specified by @code{glPixelMapusv} and
@code{glPixelMapuiv} are converted linearly such that the largest
representable integer maps to 1.0, and 0 maps to 0.0.
@code{GL_PIXEL_MAP_S_TO_S}, retain their values in fixed-point format,
with an unspecified number of bits to the right of the binary point.
Floating-point values specified by @code{glPixelMapfv} are converted
-directly to the internal fixed-point format of these maps. Unsigned
+directly to the internal fixed-point format of these maps. Unsigned
integer values specified by @code{glPixelMapusv} and
@code{glPixelMapuiv} specify integer values, with all 0's to the right
of the binary point.
The following table shows the initial sizes and values for each of the
-maps. Maps that are indexed by either color or stencil indices must have
-@var{mapsize} = @r{2^@var{n}} for some @r{@var{n}} or the results are
-undefined. The maximum allowable size for each map depends on the
+maps. Maps that are indexed by either color or stencil indices must
+have @var{mapsize} = @r{2^@var{n}} for some @r{@var{n}} or the results
+are undefined. The maximum allowable size for each map depends on the
implementation and can be determined by calling @code{glGet} with
-argument @code{GL_MAX_PIXEL_MAP_TABLE}. The single maximum applies to
+argument @code{GL_MAX_PIXEL_MAP_TABLE}. The single maximum applies to
all maps; it is at least 32.
@table @asis
@table @asis
@item @var{pname}
-Specifies the symbolic name of the parameter to be set. Six values
+Specifies the symbolic name of the parameter to be set. Six values
affect the packing of pixel data into memory: @code{GL_PACK_SWAP_BYTES},
@code{GL_PACK_LSB_FIRST}, @code{GL_PACK_ROW_LENGTH},
@code{GL_PACK_IMAGE_HEIGHT}, @code{GL_PACK_SKIP_PIXELS},
@code{GL_PACK_SKIP_ROWS}, @code{GL_PACK_SKIP_IMAGES}, and
-@code{GL_PACK_ALIGNMENT}. Six more affect the unpacking of pixel data
+@code{GL_PACK_ALIGNMENT}. Six more affect the unpacking of pixel data
@var{from} memory: @code{GL_UNPACK_SWAP_BYTES},
@code{GL_UNPACK_LSB_FIRST}, @code{GL_UNPACK_ROW_LENGTH},
@code{GL_UNPACK_IMAGE_HEIGHT}, @code{GL_UNPACK_SKIP_PIXELS},
@code{glHistogram}), and minmax (See @code{glMinmax}) data.
@var{pname} is a symbolic constant indicating the parameter to be set,
-and @var{param} is the new value. Six of the twelve storage parameters
-affect how pixel data is returned to client memory. They are as follows:
+and @var{param} is the new value. Six of the twelve storage parameters
+affect how pixel data is returned to client memory. They are as
+follows:
@table @asis
@item @code{GL_PACK_SWAP_BYTES}
If true, byte ordering for multibyte color components, depth components,
-color indices, or stencil indices is reversed. That is, if a four-byte
+color indices, or stencil indices is reversed. That is, if a four-byte
component consists of bytes @r{@var{b}_0}, @r{@var{b}_1}, @r{@var{b}_2},
@r{@var{b}_3}, it is stored in memory as @r{@var{b}_3}, @r{@var{b}_2},
@r{@var{b}_1}, @r{@var{b}_0} if @code{GL_PACK_SWAP_BYTES} is true.
@code{GL_PACK_SWAP_BYTES} has no effect on the memory order of
components within a pixel, only on the order of bytes within components
-or indices. For example, the three components of a @code{GL_RGB} format
+or indices. For example, the three components of a @code{GL_RGB} format
pixel are always stored with red first, green second, and blue third,
regardless of the value of @code{GL_PACK_SWAP_BYTES}.
@item @code{GL_PACK_LSB_FIRST}
If true, bits are ordered within a byte from least significant to most
significant; otherwise, the first bit in each byte is the most
-significant one. This parameter is significant for bitmap data only.
+significant one. This parameter is significant for bitmap data only.
@item @code{GL_PACK_ROW_LENGTH}
If greater than 0, @code{GL_PACK_ROW_LENGTH} defines the number of
-pixels in a row. If the first pixel of a row is placed at location
+pixels in a row. If the first pixel of a row is placed at location
@r{@var{p}} in memory, then the location of the first pixel of the next
row is obtained by skipping
argument to the pixel routine otherwise), @r{@var{a}} is the value of
@code{GL_PACK_ALIGNMENT}, and @r{@var{s}} is the size, in bytes, of a
single component (if @r{@var{a}<@var{s}}, then it is as if
-@r{@var{a}=@var{s}}). In the case of 1-bit values, the location of the
+@r{@var{a}=@var{s}}). In the case of 1-bit values, the location of the
next row is obtained by skipping
@r{@var{k}=8@var{a}⌈@var{n}@var{l},/8@var{a},,⌉}
components or indices.
The word @var{component} in this description refers to the nonindex
-values red, green, blue, alpha, and depth. Storage format @code{GL_RGB},
-for example, has three components per pixel: first red, then green, and
-finally blue.
+values red, green, blue, alpha, and depth. Storage format
+@code{GL_RGB}, for example, has three components per pixel: first red,
+then green, and finally blue.
@item @code{GL_PACK_IMAGE_HEIGHT}
If greater than 0, @code{GL_PACK_IMAGE_HEIGHT} defines the number of
pixels in an image three-dimensional texture volume, where ``image'' is
-defined by all pixels sharing the same third dimension index. If the
+defined by all pixels sharing the same third dimension index. If the
first pixel of a row is placed at location @r{@var{p}} in memory, then
the location of the first pixel of the next row is obtained by skipping
@r{@var{a}<@var{s}}, then it is as if @r{@var{a}=@var{s}}).
The word @var{component} in this description refers to the nonindex
-values red, green, blue, alpha, and depth. Storage format @code{GL_RGB},
-for example, has three components per pixel: first red, then green, and
-finally blue.
+values red, green, blue, alpha, and depth. Storage format
+@code{GL_RGB}, for example, has three components per pixel: first red,
+then green, and finally blue.
@item @code{GL_PACK_SKIP_PIXELS}, @code{GL_PACK_SKIP_ROWS}, and @code{GL_PACK_SKIP_IMAGES}
These values are provided as a convenience to the programmer; they
provide no functionality that cannot be duplicated simply by
-incrementing the pointer passed to @code{glReadPixels}. Setting
+incrementing the pointer passed to @code{glReadPixels}. Setting
@code{GL_PACK_SKIP_PIXELS} to @r{@var{i}} is equivalent to incrementing
the pointer by @r{@var{i}@var{n}} components or indices, where
@r{@var{n}} is the number of components or indices in each pixel.
Setting @code{GL_PACK_SKIP_ROWS} to @r{@var{j}} is equivalent to
incrementing the pointer by @r{@var{j}@var{m}} components or indices,
where @r{@var{m}} is the number of components or indices per row, as
-just computed in the @code{GL_PACK_ROW_LENGTH} section. Setting
+just computed in the @code{GL_PACK_ROW_LENGTH} section. Setting
@code{GL_PACK_SKIP_IMAGES} to @r{@var{k}} is equivalent to incrementing
the pointer by @r{@var{k}@var{p}}, where @r{@var{p}} is the number of
components or indices per image, as computed in the
@item @code{GL_PACK_ALIGNMENT}
Specifies the alignment requirements for the start of each pixel row in
-memory. The allowable values are 1 (byte-alignment), 2 (rows aligned to
+memory. The allowable values are 1 (byte-alignment), 2 (rows aligned to
even-numbered bytes), 4 (word-alignment), and 8 (rows start on
double-word boundaries).
@end table
The other six of the twelve storage parameters affect how pixel data is
-read from client memory. These values are significant for
+read from client memory. These values are significant for
@code{glDrawPixels}, @code{glTexImage1D}, @code{glTexImage2D},
@code{glTexImage3D}, @code{glTexSubImage1D}, @code{glTexSubImage2D},
@code{glTexSubImage3D}, @code{glBitmap}, and @code{glPolygonStipple}.
Additionally, if the @code{ARB_imaging} extension is supported,
@code{glColorTable}, @code{glColorSubTable},
@code{glConvolutionFilter1D}, @code{glConvolutionFilter2D}, and
-@code{glSeparableFilter2D}. They are as follows:
+@code{glSeparableFilter2D}. They are as follows:
@table @asis
@item @code{GL_UNPACK_SWAP_BYTES}
If true, byte ordering for multibyte color components, depth components,
-color indices, or stencil indices is reversed. That is, if a four-byte
+color indices, or stencil indices is reversed. That is, if a four-byte
component consists of bytes @r{@var{b}_0}, @r{@var{b}_1}, @r{@var{b}_2},
@r{@var{b}_3}, it is taken from memory as @r{@var{b}_3}, @r{@var{b}_2},
@r{@var{b}_1}, @r{@var{b}_0} if @code{GL_UNPACK_SWAP_BYTES} is true.
@code{GL_UNPACK_SWAP_BYTES} has no effect on the memory order of
components within a pixel, only on the order of bytes within components
-or indices. For example, the three components of a @code{GL_RGB} format
+or indices. For example, the three components of a @code{GL_RGB} format
pixel are always stored with red first, green second, and blue third,
regardless of the value of @code{GL_UNPACK_SWAP_BYTES}.
@item @code{GL_UNPACK_LSB_FIRST}
If true, bits are ordered within a byte from least significant to most
significant; otherwise, the first bit in each byte is the most
-significant one. This is relevant only for bitmap data.
+significant one. This is relevant only for bitmap data.
@item @code{GL_UNPACK_ROW_LENGTH}
If greater than 0, @code{GL_UNPACK_ROW_LENGTH} defines the number of
-pixels in a row. If the first pixel of a row is placed at location
+pixels in a row. If the first pixel of a row is placed at location
@r{@var{p}} in memory, then the location of the first pixel of the next
row is obtained by skipping
@r{@var{width}} argument to the pixel routine otherwise), @r{@var{a}} is
the value of @code{GL_UNPACK_ALIGNMENT}, and @r{@var{s}} is the size, in
bytes, of a single component (if @r{@var{a}<@var{s}}, then it is as if
-@r{@var{a}=@var{s}}). In the case of 1-bit values, the location of the
+@r{@var{a}=@var{s}}). In the case of 1-bit values, the location of the
next row is obtained by skipping
@r{@var{k}=8@var{a}⌈@var{n}@var{l},/8@var{a},,⌉}
components or indices.
The word @var{component} in this description refers to the nonindex
-values red, green, blue, alpha, and depth. Storage format @code{GL_RGB},
-for example, has three components per pixel: first red, then green, and
-finally blue.
+values red, green, blue, alpha, and depth. Storage format
+@code{GL_RGB}, for example, has three components per pixel: first red,
+then green, and finally blue.
@item @code{GL_UNPACK_IMAGE_HEIGHT}
If greater than 0, @code{GL_UNPACK_IMAGE_HEIGHT} defines the number of
-pixels in an image of a three-dimensional texture volume. Where
+pixels in an image of a three-dimensional texture volume. Where
``image'' is defined by all pixel sharing the same third dimension
-index. If the first pixel of a row is placed at location @r{@var{p}} in
+index. If the first pixel of a row is placed at location @r{@var{p}} in
memory, then the location of the first pixel of the next row is obtained
by skipping
@r{@var{a}<@var{s}}, then it is as if @r{@var{a}=@var{s}}).
The word @var{component} in this description refers to the nonindex
-values red, green, blue, alpha, and depth. Storage format @code{GL_RGB},
-for example, has three components per pixel: first red, then green, and
-finally blue.
+values red, green, blue, alpha, and depth. Storage format
+@code{GL_RGB}, for example, has three components per pixel: first red,
+then green, and finally blue.
@item @code{GL_UNPACK_SKIP_PIXELS} and @code{GL_UNPACK_SKIP_ROWS}
These values are provided as a convenience to the programmer; they
provide no functionality that cannot be duplicated by incrementing the
pointer passed to @code{glDrawPixels}, @code{glTexImage1D},
@code{glTexImage2D}, @code{glTexSubImage1D}, @code{glTexSubImage2D},
-@code{glBitmap}, or @code{glPolygonStipple}. Setting
+@code{glBitmap}, or @code{glPolygonStipple}. Setting
@code{GL_UNPACK_SKIP_PIXELS} to @r{@var{i}} is equivalent to
incrementing the pointer by @r{@var{i}@var{n}} components or indices,
where @r{@var{n}} is the number of components or indices in each pixel.
@item @code{GL_UNPACK_ALIGNMENT}
Specifies the alignment requirements for the start of each pixel row in
-memory. The allowable values are 1 (byte-alignment), 2 (rows aligned to
+memory. The allowable values are 1 (byte-alignment), 2 (rows aligned to
even-numbered bytes), 4 (word-alignment), and 8 (rows start on
double-word boundaries).
@end table
-@code{glPixelStoref} can be used to set any pixel store parameter. If
+@code{glPixelStoref} can be used to set any pixel store parameter. If
the parameter type is boolean, then if @var{param} is 0, the parameter
-is false; otherwise it is set to true. If @var{pname} is a integer type
+is false; otherwise it is set to true. If @var{pname} is a integer type
parameter, @var{param} is rounded to the nearest integer.
Likewise, @code{glPixelStorei} can also be used to set any of the pixel
-store parameters. Boolean parameters are set to false if @var{param} is
+store parameters. Boolean parameters are set to false if @var{param} is
0 and true otherwise.
@code{GL_INVALID_ENUM} is generated if @var{pname} is not an accepted
routines @code{glColorTable}, @code{glColorSubTable},
@code{glConvolutionFilter1D}, @code{glConvolutionFilter2D},
@code{glHistogram}, @code{glMinmax}, and @code{glSeparableFilter2D} are
-also affected. The algorithms that are specified by pixel transfer modes
-operate on pixels after they are read from the frame buffer
+also affected. The algorithms that are specified by pixel transfer
+modes operate on pixels after they are read from the frame buffer
(@code{glCopyPixels}@code{glCopyTexImage1D}, @code{glCopyTexImage2D},
@code{glCopyTexSubImage1D}, @code{glCopyTexSubImage2D},
@code{glCopyTexSubImage3D}, and @code{glReadPixels}), or unpacked from
client memory (@code{glDrawPixels}, @code{glTexImage1D},
@code{glTexImage2D}, @code{glTexImage3D}, @code{glTexSubImage1D},
-@code{glTexSubImage2D}, and @code{glTexSubImage3D}). Pixel transfer
+@code{glTexSubImage2D}, and @code{glTexSubImage3D}). Pixel transfer
operations happen in the same order, and in the same manner, regardless
-of the command that resulted in the pixel operation. Pixel storage modes
-(see @code{glPixelStore}) control the unpacking of pixels being read
-from client memory and the packing of pixels being written back into
-client memory.
+of the command that resulted in the pixel operation. Pixel storage
+modes (see @code{glPixelStore}) control the unpacking of pixels being
+read from client memory and the packing of pixels being written back
+into client memory.
Pixel transfer operations handle four fundamental pixel types:
@var{color}, @var{color index}, @var{depth}, and @var{stencil}.
@var{Color} pixels consist of four floating-point values with
unspecified mantissa and exponent sizes, scaled such that 0 represents
-zero intensity and 1 represents full intensity. @var{Color indices}
+zero intensity and 1 represents full intensity. @var{Color indices}
comprise a single fixed-point value, with unspecified precision to the
-right of the binary point. @var{Depth} pixels comprise a single
+right of the binary point. @var{Depth} pixels comprise a single
floating-point value, with unspecified mantissa and exponent sizes,
scaled such that 0.0 represents the minimum depth buffer value, and 1.0
-represents the maximum depth buffer value. Finally, @var{stencil} pixels
-comprise a single fixed-point value, with unspecified precision to the
-right of the binary point.
+represents the maximum depth buffer value. Finally, @var{stencil}
+pixels comprise a single fixed-point value, with unspecified precision
+to the right of the binary point.
The pixel transfer operations performed on the four basic pixel types
are as follows:
@table @asis
@item @var{Color}
Each of the four color components is multiplied by a scale factor, then
-added to a bias factor. That is, the red component is multiplied by
+added to a bias factor. That is, the red component is multiplied by
@code{GL_RED_SCALE}, then added to @code{GL_RED_BIAS}; the green
component is multiplied by @code{GL_GREEN_SCALE}, then added to
@code{GL_GREEN_BIAS}; the blue component is multiplied by
@code{GL_BLUE_SCALE}, then added to @code{GL_BLUE_BIAS}; and the alpha
component is multiplied by @code{GL_ALPHA_SCALE}, then added to
-@code{GL_ALPHA_BIAS}. After all four color components are scaled and
-biased, each is clamped to the range @r{[0,1]}. All color, scale, and
+@code{GL_ALPHA_BIAS}. After all four color components are scaled and
+biased, each is clamped to the range @r{[0,1]}. All color, scale, and
bias values are specified with @code{glPixelTransfer}.
If @code{GL_MAP_COLOR} is true, each color component is scaled by the
size of the corresponding color-to-color map, then replaced by the
-contents of that map indexed by the scaled component. That is, the red
+contents of that map indexed by the scaled component. That is, the red
component is scaled by @code{GL_PIXEL_MAP_R_TO_R_SIZE}, then replaced by
-the contents of @code{GL_PIXEL_MAP_R_TO_R} indexed by itself. The green
+the contents of @code{GL_PIXEL_MAP_R_TO_R} indexed by itself. The green
component is scaled by @code{GL_PIXEL_MAP_G_TO_G_SIZE}, then replaced by
-the contents of @code{GL_PIXEL_MAP_G_TO_G} indexed by itself. The blue
+the contents of @code{GL_PIXEL_MAP_G_TO_G} indexed by itself. The blue
component is scaled by @code{GL_PIXEL_MAP_B_TO_B_SIZE}, then replaced by
-the contents of @code{GL_PIXEL_MAP_B_TO_B} indexed by itself. And the
+the contents of @code{GL_PIXEL_MAP_B_TO_B} indexed by itself. And the
alpha component is scaled by @code{GL_PIXEL_MAP_A_TO_A_SIZE}, then
replaced by the contents of @code{GL_PIXEL_MAP_A_TO_A} indexed by
-itself. All components taken from the maps are then clamped to the range
-@r{[0,1]}. @code{GL_MAP_COLOR} is specified with @code{glPixelTransfer}.
-The contents of the various maps are specified with @code{glPixelMap}.
+itself. All components taken from the maps are then clamped to the
+range @r{[0,1]}. @code{GL_MAP_COLOR} is specified with
+@code{glPixelTransfer}. The contents of the various maps are specified
+with @code{glPixelMap}.
If the @code{ARB_imaging} extension is supported, each of the four color
components may be scaled and biased after transformation by the color
-matrix. That is, the red component is multiplied by
+matrix. That is, the red component is multiplied by
@code{GL_POST_COLOR_MATRIX_RED_SCALE}, then added to
@code{GL_POST_COLOR_MATRIX_RED_BIAS}; the green component is multiplied
by @code{GL_POST_COLOR_MATRIX_GREEN_SCALE}, then added to
by @code{GL_POST_COLOR_MATRIX_BLUE_SCALE}, then added to
@code{GL_POST_COLOR_MATRIX_BLUE_BIAS}; and the alpha component is
multiplied by @code{GL_POST_COLOR_MATRIX_ALPHA_SCALE}, then added to
-@code{GL_POST_COLOR_MATRIX_ALPHA_BIAS}. After all four color components
+@code{GL_POST_COLOR_MATRIX_ALPHA_BIAS}. After all four color components
are scaled and biased, each is clamped to the range @r{[0,1]}.
Similarly, if the @code{ARB_imaging} extension is supported, each of the
four color components may be scaled and biased after processing by the
-enabled convolution filter. That is, the red component is multiplied by
+enabled convolution filter. That is, the red component is multiplied by
@code{GL_POST_CONVOLUTION_RED_SCALE}, then added to
@code{GL_POST_CONVOLUTION_RED_BIAS}; the green component is multiplied
by @code{GL_POST_CONVOLUTION_GREEN_SCALE}, then added to
by @code{GL_POST_CONVOLUTION_BLUE_SCALE}, then added to
@code{GL_POST_CONVOLUTION_BLUE_BIAS}; and the alpha component is
multiplied by @code{GL_POST_CONVOLUTION_ALPHA_SCALE}, then added to
-@code{GL_POST_CONVOLUTION_ALPHA_BIAS}. After all four color components
+@code{GL_POST_CONVOLUTION_ALPHA_BIAS}. After all four color components
are scaled and biased, each is clamped to the range @r{[0,1]}.
@item @var{Color index}
Each color index is shifted left by @code{GL_INDEX_SHIFT} bits; any bits
beyond the number of fraction bits carried by the fixed-point index are
-filled with zeros. If @code{GL_INDEX_SHIFT} is negative, the shift is to
-the right, again zero filled. Then @code{GL_INDEX_OFFSET} is added to
-the index. @code{GL_INDEX_SHIFT} and @code{GL_INDEX_OFFSET} are
+filled with zeros. If @code{GL_INDEX_SHIFT} is negative, the shift is
+to the right, again zero filled. Then @code{GL_INDEX_OFFSET} is added
+to the index. @code{GL_INDEX_SHIFT} and @code{GL_INDEX_OFFSET} are
specified with @code{glPixelTransfer}.
From this point, operation diverges depending on the required format of
-the resulting pixels. If the resulting pixels are to be written to a
+the resulting pixels. If the resulting pixels are to be written to a
color index buffer, or if they are being read back to client memory in
@code{GL_COLOR_INDEX} format, the pixels continue to be treated as
-indices. If @code{GL_MAP_COLOR} is true, each index is masked by
+indices. If @code{GL_MAP_COLOR} is true, each index is masked by
@r{2^@var{n}-1}, where @r{@var{n}} is @code{GL_PIXEL_MAP_I_TO_I_SIZE},
then replaced by the contents of @code{GL_PIXEL_MAP_I_TO_I} indexed by
-the masked value. @code{GL_MAP_COLOR} is specified with
-@code{glPixelTransfer}. The contents of the index map is specified with
+the masked value. @code{GL_MAP_COLOR} is specified with
+@code{glPixelTransfer}. The contents of the index map is specified with
@code{glPixelMap}.
If the resulting pixels are to be written to an RGBA color buffer, or if
@code{GL_COLOR_INDEX}, the pixels are converted from indices to colors
by referencing the four maps @code{GL_PIXEL_MAP_I_TO_R},
@code{GL_PIXEL_MAP_I_TO_G}, @code{GL_PIXEL_MAP_I_TO_B}, and
-@code{GL_PIXEL_MAP_I_TO_A}. Before being dereferenced, the index is
+@code{GL_PIXEL_MAP_I_TO_A}. Before being dereferenced, the index is
masked by @r{2^@var{n}-1}, where @r{@var{n}} is
@code{GL_PIXEL_MAP_I_TO_R_SIZE} for the red map,
@code{GL_PIXEL_MAP_I_TO_G_SIZE} for the green map,
@code{GL_PIXEL_MAP_I_TO_B_SIZE} for the blue map, and
-@code{GL_PIXEL_MAP_I_TO_A_SIZE} for the alpha map. All components taken
-from the maps are then clamped to the range @r{[0,1]}. The contents of
+@code{GL_PIXEL_MAP_I_TO_A_SIZE} for the alpha map. All components taken
+from the maps are then clamped to the range @r{[0,1]}. The contents of
the four maps is specified with @code{glPixelMap}.
@item @var{Depth}
@item @var{Stencil}
Each index is shifted @code{GL_INDEX_SHIFT} bits just as a color index
-is, then added to @code{GL_INDEX_OFFSET}. If @code{GL_MAP_STENCIL} is
+is, then added to @code{GL_INDEX_OFFSET}. If @code{GL_MAP_STENCIL} is
true, each index is masked by @r{2^@var{n}-1}, where @r{@var{n}} is
@code{GL_PIXEL_MAP_S_TO_S_SIZE}, then replaced by the contents of
@code{GL_PIXEL_MAP_S_TO_S} indexed by the masked value.
@code{glPixelTransferf} can be used to set any pixel transfer parameter.
If the parameter type is boolean, 0 implies false and any other value
-implies true. If @var{pname} is an integer parameter, @var{param} is
+implies true. If @var{pname} is an integer parameter, @var{param} is
rounded to the nearest integer.
Likewise, @code{glPixelTransferi} can be used to set any of the pixel
-transfer parameters. Boolean parameters are set to false if @var{param}
-is 0 and to true otherwise. @var{param} is converted to floating point
+transfer parameters. Boolean parameters are set to false if @var{param}
+is 0 and to true otherwise. @var{param} is converted to floating point
before being assigned to real-valued parameters.
@code{GL_INVALID_ENUM} is generated if @var{pname} is not an accepted
@end table
@code{glPixelZoom} specifies values for the @r{@var{x}} and @r{@var{y}}
-zoom factors. During the execution of @code{glDrawPixels} or
+zoom factors. During the execution of @code{glDrawPixels} or
@code{glCopyPixels}, if (@r{@var{xr}}, @r{@var{yr}}) is the current
raster position, and a given element is in the @r{@var{m}}th row and
@r{@var{n}}th column of the pixel rectangle, then pixels whose centers
(@r{@var{xr}+(@var{n}+1,)·@var{xfactor}},
@r{@var{yr}+(@var{m}+1,)·@var{yfactor}})
-are candidates for replacement. Any pixel whose center lies on the
+are candidates for replacement. Any pixel whose center lies on the
bottom or left edge of this rectangular region is also modified.
-Pixel zoom factors are not limited to positive values. Negative zoom
+Pixel zoom factors are not limited to positive values. Negative zoom
factors reflect the resulting image about the current raster position.
@code{GL_INVALID_OPERATION} is generated if @code{glPixelZoom} is
@table @asis
@item @var{pname}
-Specifies a single-valued point parameter. @code{GL_POINT_SIZE_MIN},
+Specifies a single-valued point parameter. @code{GL_POINT_SIZE_MIN},
@code{GL_POINT_SIZE_MAX}, @code{GL_POINT_FADE_THRESHOLD_SIZE}, and
@code{GL_POINT_SPRITE_COORD_ORIGIN} are accepted.
@var{params} is a single floating-point value that specifies the minimum
-point size. The default value is 0.0.
+point size. The default value is 0.0.
@item @code{GL_POINT_SIZE_MAX}
@var{params} is a single floating-point value that specifies the maximum
-point size. The default value is 1.0.
+point size. The default value is 1.0.
@item @code{GL_POINT_FADE_THRESHOLD_SIZE}
@var{params} is a single floating-point value that specifies the
threshold value to which point sizes are clamped if they exceed the
-specified value. The default value is 1.0.
+specified value. The default value is 1.0.
@item @code{GL_POINT_DISTANCE_ATTENUATION}
@var{params} is an array of three floating-point values that specify the
-coefficients used for scaling the computed point size. The default
+coefficients used for scaling the computed point size. The default
values are @r{(1,00)}.
@item @code{GL_POINT_SPRITE_COORD_ORIGIN}
@table @asis
@item @var{size}
-Specifies the diameter of rasterized points. The initial value is 1.
+Specifies the diameter of rasterized points. The initial value is 1.
@end table
@code{glPointSize} specifies the rasterized diameter of both aliased and
-antialiased points. Using a point size other than 1 has different
-effects, depending on whether point antialiasing is enabled. To enable
+antialiased points. Using a point size other than 1 has different
+effects, depending on whether point antialiasing is enabled. To enable
and disable point antialiasing, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_POINT_SMOOTH}. Point
+@code{glDisable} with argument @code{GL_POINT_SMOOTH}. Point
antialiasing is initially disabled.
The specified point size is multiplied with a distance attenuation
(@var{otherwise}),}
If point antialiasing is disabled, the actual size is determined by
-rounding the supplied size to the nearest integer. (If the rounding
+rounding the supplied size to the nearest integer. (If the rounding
results in the value 0, it is as if the point size were 1.) If the
rounded size is odd, then the center point (@r{@var{x}}, @r{@var{y}}) of
the pixel fragment that represents the point is computed as
@r{(⌊@var{x}_@var{w},⌋+.5,⌊@var{y}_@var{w},⌋+.5)}
-where @r{@var{w}} subscripts indicate window coordinates. All pixels
+where @r{@var{w}} subscripts indicate window coordinates. All pixels
that lie within the square grid of the rounded size centered at
-(@r{@var{x}}, @r{@var{y}}) make up the fragment. If the size is even,
+(@r{@var{x}}, @r{@var{y}}) make up the fragment. If the size is even,
the center point is
@r{(⌊@var{x}_@var{w}+.5,⌋,⌊@var{y}_@var{w}+.5,⌋)}
and the rasterized fragment's centers are the half-integer window
coordinates within the square of the rounded size centered at
-@r{(@var{x},@var{y})}. All pixel fragments produced in rasterizing a
+@r{(@var{x},@var{y})}. All pixel fragments produced in rasterizing a
nonantialiased point are assigned the same associated data, that of the
vertex corresponding to the point.
If antialiasing is enabled, then point rasterization produces a fragment
for each pixel square that intersects the region lying within the circle
having diameter equal to the current point size and centered at the
-point's @r{(@var{x}_@var{w},@var{y}_@var{w})}. The coverage value for
+point's @r{(@var{x}_@var{w},@var{y}_@var{w})}. The coverage value for
each fragment is the window coordinate area of the intersection of the
-circular region with the corresponding pixel square. This value is saved
-and used in the final rasterization step. The data associated with each
-fragment is the data associated with the point being rasterized.
+circular region with the corresponding pixel square. This value is
+saved and used in the final rasterization step. The data associated
+with each fragment is the data associated with the point being
+rasterized.
-Not all sizes are supported when point antialiasing is enabled. If an
-unsupported size is requested, the nearest supported size is used. Only
+Not all sizes are supported when point antialiasing is enabled. If an
+unsupported size is requested, the nearest supported size is used. Only
size 1 is guaranteed to be supported; others depend on the
-implementation. To query the range of supported sizes and the size
+implementation. To query the range of supported sizes and the size
difference between supported sizes within the range, call @code{glGet}
with arguments @code{GL_SMOOTH_POINT_SIZE_RANGE} and
-@code{GL_SMOOTH_POINT_SIZE_GRANULARITY}. For aliased points, query the
+@code{GL_SMOOTH_POINT_SIZE_GRANULARITY}. For aliased points, query the
supported ranges and granularity with @code{glGet} with arguments
@code{GL_ALIASED_POINT_SIZE_RANGE}.
@table @asis
@item @var{face}
-Specifies the polygons that @var{mode} applies to. Must be
+Specifies the polygons that @var{mode} applies to. Must be
@code{GL_FRONT} for front-facing polygons, @code{GL_BACK} for
back-facing polygons, or @code{GL_FRONT_AND_BACK} for front- and
back-facing polygons.
@item @var{mode}
-Specifies how polygons will be rasterized. Accepted values are
-@code{GL_POINT}, @code{GL_LINE}, and @code{GL_FILL}. The initial value
+Specifies how polygons will be rasterized. Accepted values are
+@code{GL_POINT}, @code{GL_LINE}, and @code{GL_FILL}. The initial value
is @code{GL_FILL} for both front- and back-facing polygons.
@end table
@code{glPolygonMode} controls the interpretation of polygons for
-rasterization. @var{face} describes which polygons @var{mode} applies
+rasterization. @var{face} describes which polygons @var{mode} applies
to: front-facing polygons (@code{GL_FRONT}), back-facing polygons
-(@code{GL_BACK}), or both (@code{GL_FRONT_AND_BACK}). The polygon mode
-affects only the final rasterization of polygons. In particular, a
+(@code{GL_BACK}), or both (@code{GL_FRONT_AND_BACK}). The polygon mode
+affects only the final rasterization of polygons. In particular, a
polygon's vertices are lit and the polygon is clipped and possibly
culled before these modes are applied.
@table @asis
@item @code{GL_POINT}
Polygon vertices that are marked as the start of a boundary edge are
-drawn as points. Point attributes such as @code{GL_POINT_SIZE} and
-@code{GL_POINT_SMOOTH} control the rasterization of the points. Polygon
+drawn as points. Point attributes such as @code{GL_POINT_SIZE} and
+@code{GL_POINT_SMOOTH} control the rasterization of the points. Polygon
rasterization attributes other than @code{GL_POLYGON_MODE} have no
effect.
@item @code{GL_LINE}
-Boundary edges of the polygon are drawn as line segments. They are
+Boundary edges of the polygon are drawn as line segments. They are
treated as connected line segments for line stippling; the line stipple
counter and pattern are not reset between segments (see
-@code{glLineStipple}). Line attributes such as @code{GL_LINE_WIDTH} and
-@code{GL_LINE_SMOOTH} control the rasterization of the lines. Polygon
+@code{glLineStipple}). Line attributes such as @code{GL_LINE_WIDTH} and
+@code{GL_LINE_SMOOTH} control the rasterization of the lines. Polygon
rasterization attributes other than @code{GL_POLYGON_MODE} have no
effect.
@item @code{GL_FILL}
-The interior of the polygon is filled. Polygon attributes such as
+The interior of the polygon is filled. Polygon attributes such as
@code{GL_POLYGON_STIPPLE} and @code{GL_POLYGON_SMOOTH} control the
rasterization of the polygon.
@table @asis
@item @var{factor}
Specifies a scale factor that is used to create a variable depth offset
-for each polygon. The initial value is 0.
+for each polygon. The initial value is 0.
@item @var{units}
Is multiplied by an implementation-specific value to create a constant
-depth offset. The initial value is 0.
+depth offset. The initial value is 0.
@end table
When @code{GL_POLYGON_OFFSET_FILL}, @code{GL_POLYGON_OFFSET_LINE}, or
@code{GL_POLYGON_OFFSET_POINT} is enabled, each fragment's @var{depth}
value will be offset after it is interpolated from the @var{depth}
-values of the appropriate vertices. The value of the offset is
+values of the appropriate vertices. The value of the offset is
@r{@var{factor}×@var{DZ}+@var{r}×@var{units}}, where @r{@var{DZ}} is a
measurement of the change in depth relative to the screen area of the
polygon, and @r{@var{r}} is the smallest value that is guaranteed to
-produce a resolvable offset for a given implementation. The offset is
+produce a resolvable offset for a given implementation. The offset is
added before the depth test is performed and before the value is written
into the depth buffer.
@var{pattern} is a pointer to a @r{32×32} stipple pattern that is stored
in memory just like the pixel data supplied to a @code{glDrawPixels}
call with height and @var{width} both equal to 32, a pixel format of
-@code{GL_COLOR_INDEX}, and data type of @code{GL_BITMAP}. That is, the
+@code{GL_COLOR_INDEX}, and data type of @code{GL_BITMAP}. That is, the
stipple pattern is represented as a @r{32×32} array of 1-bit color
-indices packed in unsigned bytes. @code{glPixelStore} parameters like
+indices packed in unsigned bytes. @code{glPixelStore} parameters like
@code{GL_UNPACK_SWAP_BYTES} and @code{GL_UNPACK_LSB_FIRST} affect the
-assembling of the bits into a stipple pattern. Pixel transfer operations
-(shift, offset, pixel map) are not applied to the stipple image,
-however.
+assembling of the bits into a stipple pattern. Pixel transfer
+operations (shift, offset, pixel map) are not applied to the stipple
+image, however.
If a non-zero named buffer object is bound to the
@code{GL_PIXEL_UNPACK_BUFFER} target (see @code{glBindBuffer}) while a
into the buffer object's data store.
To enable and disable polygon stippling, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_POLYGON_STIPPLE}. Polygon
-stippling is initially disabled. If it's enabled, a rasterized polygon
+@code{glDisable} with argument @code{GL_POLYGON_STIPPLE}. Polygon
+stippling is initially disabled. If it's enabled, a rasterized polygon
fragment with window coordinates @r{@var{x}_@var{w}} and
@r{@var{y}_@var{w}} is sent to the next stage of the GL if and only if
the (@r{@var{x}_@var{w}%32})th bit in the (@r{@var{y}_@var{w}%32})th row
-of the stipple pattern is 1 (one). When polygon stippling is disabled,
+of the stipple pattern is 1 (one). When polygon stippling is disabled,
it is as if the stipple pattern consists of all 1's.
@code{GL_INVALID_OPERATION} is generated if a non-zero buffer object
prioritized.
@item @var{priorities}
-Specifies an array containing the texture priorities. A priority given
+Specifies an array containing the texture priorities. A priority given
in an element of @var{priorities} applies to the texture named by the
corresponding element of @var{textures}.
in @var{priorities} to the @var{n} textures named in @var{textures}.
The GL establishes a ``working set'' of textures that are resident in
-texture memory. These textures may be bound to a texture target much
-more efficiently than textures that are not resident. By specifying a
+texture memory. These textures may be bound to a texture target much
+more efficiently than textures that are not resident. By specifying a
priority for each texture, @code{glPrioritizeTextures} allows
applications to guide the GL implementation in determining which
textures should be resident.
The priorities given in @var{priorities} are clamped to the range
-@r{[0,1]} before they are assigned. 0 indicates the lowest priority;
-textures with priority 0 are least likely to be resident. 1 indicates
+@r{[0,1]} before they are assigned. 0 indicates the lowest priority;
+textures with priority 0 are least likely to be resident. 1 indicates
the highest priority; textures with priority 1 are most likely to be
-resident. However, textures are not guaranteed to be resident until they
-are used.
+resident. However, textures are not guaranteed to be resident until
+they are used.
@code{glPrioritizeTextures} silently ignores attempts to prioritize
texture 0 or any texture name that does not correspond to an existing
@code{glPrioritizeTextures} does not require that any of the textures
named by @var{textures} be bound to a texture target.
@code{glTexParameter} may also be used to set a texture's priority, but
-only if the texture is currently bound. This is the only way to set the
+only if the texture is currently bound. This is the only way to set the
priority of a default texture.
@code{GL_INVALID_VALUE} is generated if @var{n} is negative.
@table @asis
@item @var{mask}
-Specifies a mask that indicates which attributes to save. Values for
+Specifies a mask that indicates which attributes to save. Values for
@var{mask} are listed below.
@end table
@code{glPushAttrib} takes one argument, a mask that indicates which
-groups of state variables to save on the attribute stack. Symbolic
-constants are used to set bits in the mask. @var{mask} is typically
+groups of state variables to save on the attribute stack. Symbolic
+constants are used to set bits in the mask. @var{mask} is typically
constructed by specifying the bitwise-or of several of these constants
-together. The special mask @code{GL_ALL_ATTRIB_BITS} can be used to save
-all stackable states.
+together. The special mask @code{GL_ALL_ATTRIB_BITS} can be used to
+save all stackable states.
The symbolic mask constants and their associated GL state are as follows
(the second column lists which attributes are saved):
@end table
@code{glPopAttrib} restores the values of the state variables saved with
-the last @code{glPushAttrib} command. Those not saved are left
+the last @code{glPushAttrib} command. Those not saved are left
unchanged.
It is an error to push attributes onto a full stack or to pop attributes
-off an empty stack. In either case, the error flag is set and no other
+off an empty stack. In either case, the error flag is set and no other
change is made to GL state.
Initially, the attribute stack is empty.
@table @asis
@item @var{mask}
-Specifies a mask that indicates which attributes to save. Values for
+Specifies a mask that indicates which attributes to save. Values for
@var{mask} are listed below.
@end table
@code{glPushClientAttrib} takes one argument, a mask that indicates
which groups of client-state variables to save on the client attribute
-stack. Symbolic constants are used to set bits in the mask. @var{mask}
+stack. Symbolic constants are used to set bits in the mask. @var{mask}
is typically constructed by specifying the bitwise-or of several of
-these constants together. The special mask
+these constants together. The special mask
@code{GL_CLIENT_ALL_ATTRIB_BITS} can be used to save all stackable
client state.
@code{GL_CLIENT_VERTEX_ARRAY_BIT} Vertex arrays (and enables)
@code{glPopClientAttrib} restores the values of the client-state
-variables saved with the last @code{glPushClientAttrib}. Those not saved
-are left unchanged.
+variables saved with the last @code{glPushClientAttrib}. Those not
+saved are left unchanged.
It is an error to push attributes onto a full client attribute stack or
-to pop attributes off an empty stack. In either case, the error flag is
+to pop attributes off an empty stack. In either case, the error flag is
set, and no other change is made to GL state.
Initially, the client attribute stack is empty.
@deftypefunx void glPopMatrix
Push and pop the current matrix stack.
-There is a stack of matrices for each of the matrix modes. In
-@code{GL_MODELVIEW} mode, the stack depth is at least 32. In the other
+There is a stack of matrices for each of the matrix modes. In
+@code{GL_MODELVIEW} mode, the stack depth is at least 32. In the other
modes, @code{GL_COLOR}, @code{GL_PROJECTION}, and @code{GL_TEXTURE}, the
-depth is at least 2. The current matrix in any mode is the matrix on the
-top of the stack for that mode.
+depth is at least 2. The current matrix in any mode is the matrix on
+the top of the stack for that mode.
@code{glPushMatrix} pushes the current matrix stack down by one,
-duplicating the current matrix. That is, after a @code{glPushMatrix}
+duplicating the current matrix. That is, after a @code{glPushMatrix}
call, the matrix on top of the stack is identical to the one below it.
@code{glPopMatrix} pops the current matrix stack, replacing the current
Initially, each of the stacks contains one matrix, an identity matrix.
It is an error to push a full matrix stack or to pop a matrix stack that
-contains only a single matrix. In either case, the error flag is set and
-no other change is made to GL state.
+contains only a single matrix. In either case, the error flag is set
+and no other change is made to GL state.
@code{GL_STACK_OVERFLOW} is generated if @code{glPushMatrix} is called
while the current matrix stack is full.
@end table
The name stack is used during selection mode to allow sets of rendering
-commands to be uniquely identified. It consists of an ordered set of
+commands to be uniquely identified. It consists of an ordered set of
unsigned integers and is initially empty.
@code{glPushName} causes @var{name} to be pushed onto the name stack.
The maximum name stack depth is implementation-dependent; call
@code{GL_MAX_NAME_STACK_DEPTH} to find out the value for a particular
-implementation. It is an error to push a name onto a full stack or to
-pop a name off an empty stack. It is also an error to manipulate the
+implementation. It is an error to push a name onto a full stack or to
+pop a name off an empty stack. It is also an error to manipulate the
name stack between the execution of @code{glBegin} and the corresponding
-execution of @code{glEnd}. In any of these cases, the error flag is set
+execution of @code{glEnd}. In any of these cases, the error flag is set
and no other change is made to GL state.
The name stack is always empty while the render mode is not
-@code{GL_SELECT}. Calls to @code{glPushName} or @code{glPopName} while
+@code{GL_SELECT}. Calls to @code{glPushName} or @code{glPopName} while
the render mode is not @code{GL_SELECT} are ignored.
@code{GL_STACK_OVERFLOW} is generated if @code{glPushName} is called
@end table
-The GL maintains a 3D position in window coordinates. This position,
+The GL maintains a 3D position in window coordinates. This position,
called the raster position, is used to position pixel and bitmap write
-operations. It is maintained with subpixel accuracy. See
+operations. It is maintained with subpixel accuracy. See
@code{glBitmap}, @code{glDrawPixels}, and @code{glCopyPixels}.
The current raster position consists of three window coordinates
(@r{@var{x}}, @r{@var{y}}, @r{@var{z}}), a clip coordinate value
(@r{@var{w}}), an eye coordinate distance, a valid bit, and associated
-color data and texture coordinates. The @r{@var{w}} coordinate is a clip
-coordinate, because @r{@var{w}} is not projected to window coordinates.
-@code{glRasterPos4} specifies object coordinates @r{@var{x}},
-@r{@var{y}}, @r{@var{z}}, and @r{@var{w}} explicitly.
+color data and texture coordinates. The @r{@var{w}} coordinate is a
+clip coordinate, because @r{@var{w}} is not projected to window
+coordinates. @code{glRasterPos4} specifies object coordinates
+@r{@var{x}}, @r{@var{y}}, @r{@var{z}}, and @r{@var{w}} explicitly.
@code{glRasterPos3} specifies object coordinate @r{@var{x}},
@r{@var{y}}, and @r{@var{z}} explicitly, while @r{@var{w}} is implicitly
-set to 1. @code{glRasterPos2} uses the argument values for @r{@var{x}}
+set to 1. @code{glRasterPos2} uses the argument values for @r{@var{x}}
and @r{@var{y}} while implicitly setting @r{@var{z}} and @r{@var{w}} to
0 and 1.
The object coordinates presented by @code{glRasterPos} are treated just
like those of a @code{glVertex} command: They are transformed by the
current modelview and projection matrices and passed to the clipping
-stage. If the vertex is not culled, then it is projected and scaled to
+stage. If the vertex is not culled, then it is projected and scaled to
window coordinates, which become the new current raster position, and
-the @code{GL_CURRENT_RASTER_POSITION_VALID} flag is set. If the vertex
+the @code{GL_CURRENT_RASTER_POSITION_VALID} flag is set. If the vertex
@var{is} culled, then the valid bit is cleared and the current raster
position and associated color and texture coordinates are undefined.
The current raster position also includes some associated color data and
-texture coordinates. If lighting is enabled, then
+texture coordinates. If lighting is enabled, then
@code{GL_CURRENT_RASTER_COLOR} (in RGBA mode) or
@code{GL_CURRENT_RASTER_INDEX} (in color index mode) is set to the color
produced by the lighting calculation (see @code{glLight},
-@code{glLightModel}, and @code{glShadeModel}). If lighting is disabled,
+@code{glLightModel}, and @code{glShadeModel}). If lighting is disabled,
current color (in RGBA mode, state variable @code{GL_CURRENT_COLOR}) or
color index (in color index mode, state variable
@code{GL_CURRENT_INDEX}) is used to update the current raster color.
Initially, the current raster position is (0, 0, 0, 1), the current
raster distance is 0, the valid bit is set, the associated RGBA color is
(1, 1, 1, 1), the associated color index is 1, and the associated
-texture coordinates are (0, 0, 0, 1). In RGBA mode,
+texture coordinates are (0, 0, 0, 1). In RGBA mode,
@code{GL_CURRENT_RASTER_INDEX} is always 1; in color index mode, the
current raster RGBA color always maintains its initial value.
@table @asis
@item @var{mode}
-Specifies a color buffer. Accepted values are @code{GL_FRONT_LEFT},
+Specifies a color buffer. Accepted values are @code{GL_FRONT_LEFT},
@code{GL_FRONT_RIGHT}, @code{GL_BACK_LEFT}, @code{GL_BACK_RIGHT},
@code{GL_FRONT}, @code{GL_BACK}, @code{GL_LEFT}, @code{GL_RIGHT}, and
@code{GL_AUX}@var{i}, where @var{i} is between 0 and the value of
subsequent @code{glReadPixels}, @code{glCopyTexImage1D},
@code{glCopyTexImage2D}, @code{glCopyTexSubImage1D},
@code{glCopyTexSubImage2D}, @code{glCopyTexSubImage3D}, and
-@code{glCopyPixels} commands. @var{mode} accepts one of twelve or more
-predefined values. (@code{GL_AUX0} through @code{GL_AUX3} are always
+@code{glCopyPixels} commands. @var{mode} accepts one of twelve or more
+predefined values. (@code{GL_AUX0} through @code{GL_AUX3} are always
defined.) In a fully configured system, @code{GL_FRONT}, @code{GL_LEFT},
and @code{GL_FRONT_LEFT} all name the front left buffer,
@code{GL_FRONT_RIGHT} and @code{GL_RIGHT} name the front right buffer,
and @code{GL_BACK_LEFT} and @code{GL_BACK} name the back left buffer.
Nonstereo double-buffered configurations have only a front left and a
-back left buffer. Single-buffered configurations have a front left and a
-front right buffer if stereo, and only a front left buffer if nonstereo.
-It is an error to specify a nonexistent buffer to @code{glReadBuffer}.
+back left buffer. Single-buffered configurations have a front left and
+a front right buffer if stereo, and only a front left buffer if
+nonstereo. It is an error to specify a nonexistent buffer to
+@code{glReadBuffer}.
@var{mode} is initially @code{GL_FRONT} in single-buffered
configurations and @code{GL_BACK} in double-buffered configurations.
@item @var{x}
@itemx @var{y}
Specify the window coordinates of the first pixel that is read from the
-frame buffer. This location is the lower left corner of a rectangular
+frame buffer. This location is the lower left corner of a rectangular
block of pixels.
@item @var{width}
@itemx @var{height}
-Specify the dimensions of the pixel rectangle. @var{width} and
+Specify the dimensions of the pixel rectangle. @var{width} and
@var{height} of one correspond to a single pixel.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_STENCIL_INDEX},
@code{GL_DEPTH_COMPONENT}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. Must be one of
+Specifies the data type of the pixel data. Must be one of
@code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
@code{glReadPixels} returns pixel data from the frame buffer, starting
with the pixel whose lower left corner is at location (@var{x},
-@var{y}), into client memory starting at location @var{data}. Several
+@var{y}), into client memory starting at location @var{data}. Several
parameters control the processing of the pixel data before it is placed
-into client memory. These parameters are set with three commands:
-@code{glPixelStore}, @code{glPixelTransfer}, and @code{glPixelMap}. This
+into client memory. These parameters are set with three commands:
+@code{glPixelStore}, @code{glPixelTransfer}, and @code{glPixelMap}. This
reference page describes the effects on @code{glReadPixels} of most, but
not all of the parameters specified by these three commands.
@code{glReadPixels} returns values from each pixel with lower left
corner at @r{(@var{x}+@var{i},@var{y}+@var{j})} for
-@r{0<=@var{i}<@var{width}} and @r{0<=@var{j}<@var{height}}. This pixel
-is said to be the @r{@var{i}}th pixel in the @r{@var{j}}th row. Pixels
+@r{0<=@var{i}<@var{width}} and @r{0<=@var{j}<@var{height}}. This pixel
+is said to be the @r{@var{i}}th pixel in the @r{@var{j}}th row. Pixels
are returned in row order from the lowest to the highest row, left to
right in each row.
@table @asis
@item @code{GL_COLOR_INDEX}
Color indices are read from the color buffer selected by
-@code{glReadBuffer}. Each index is converted to fixed point, shifted
+@code{glReadBuffer}. Each index is converted to fixed point, shifted
left or right depending on the value and sign of @code{GL_INDEX_SHIFT},
-and added to @code{GL_INDEX_OFFSET}. If @code{GL_MAP_COLOR} is
+and added to @code{GL_INDEX_OFFSET}. If @code{GL_MAP_COLOR} is
@code{GL_TRUE}, indices are replaced by their mappings in the table
@code{GL_PIXEL_MAP_I_TO_I}.
@item @code{GL_STENCIL_INDEX}
-Stencil values are read from the stencil buffer. Each index is converted
-to fixed point, shifted left or right depending on the value and sign of
-@code{GL_INDEX_SHIFT}, and added to @code{GL_INDEX_OFFSET}. If
-@code{GL_MAP_STENCIL} is @code{GL_TRUE}, indices are replaced by their
-mappings in the table @code{GL_PIXEL_MAP_S_TO_S}.
+Stencil values are read from the stencil buffer. Each index is
+converted to fixed point, shifted left or right depending on the value
+and sign of @code{GL_INDEX_SHIFT}, and added to @code{GL_INDEX_OFFSET}.
+If @code{GL_MAP_STENCIL} is @code{GL_TRUE}, indices are replaced by
+their mappings in the table @code{GL_PIXEL_MAP_S_TO_S}.
@item @code{GL_DEPTH_COMPONENT}
-Depth values are read from the depth buffer. Each component is converted
-to floating point such that the minimum depth value maps to 0 and the
-maximum value maps to 1. Each component is then multiplied by
+Depth values are read from the depth buffer. Each component is
+converted to floating point such that the minimum depth value maps to 0
+and the maximum value maps to 1. Each component is then multiplied by
@code{GL_DEPTH_SCALE}, added to @code{GL_DEPTH_BIAS}, and finally
clamped to the range @r{[0,1]}.
@item @code{GL_LUMINANCE}
@item @code{GL_LUMINANCE_ALPHA}
Processing differs depending on whether color buffers store color
-indices or RGBA color components. If color indices are stored, they are
-read from the color buffer selected by @code{glReadBuffer}. Each index
+indices or RGBA color components. If color indices are stored, they are
+read from the color buffer selected by @code{glReadBuffer}. Each index
is converted to fixed point, shifted left or right depending on the
value and sign of @code{GL_INDEX_SHIFT}, and added to
-@code{GL_INDEX_OFFSET}. Indices are then replaced by the red, green,
+@code{GL_INDEX_OFFSET}. Indices are then replaced by the red, green,
blue, and alpha values obtained by indexing the tables
@code{GL_PIXEL_MAP_I_TO_R}, @code{GL_PIXEL_MAP_I_TO_G},
-@code{GL_PIXEL_MAP_I_TO_B}, and @code{GL_PIXEL_MAP_I_TO_A}. Each table
+@code{GL_PIXEL_MAP_I_TO_B}, and @code{GL_PIXEL_MAP_I_TO_A}. Each table
must be of size @r{2^@var{n}}, but @r{@var{n}} may be different for
-different tables. Before an index is used to look up a value in a table
+different tables. Before an index is used to look up a value in a table
of size @r{2^@var{n}}, it must be masked against @r{2^@var{n}-1}.
If RGBA color components are stored in the color buffers, they are read
-from the color buffer selected by @code{glReadBuffer}. Each color
+from the color buffer selected by @code{glReadBuffer}. Each color
component is converted to floating point such that zero intensity maps
-to 0.0 and full intensity maps to 1.0. Each component is then multiplied
-by @code{GL_c_SCALE} and added to @code{GL_c_BIAS}, where @var{c} is
-RED, GREEN, BLUE, or ALPHA. Finally, if @code{GL_MAP_COLOR} is
-@code{GL_TRUE}, each component is clamped to the range @r{[0,1]}, scaled
-to the size of its corresponding table, and is then replaced by its
-mapping in the table @code{GL_PIXEL_MAP_c_TO_c}, where @var{c} is R, G,
-B, or A.
-
-Unneeded data is then discarded. For example, @code{GL_RED} discards the
-green, blue, and alpha components, while @code{GL_RGB} discards only the
-alpha component. @code{GL_LUMINANCE} computes a single-component value
-as the sum of the red, green, and blue components, and
+to 0.0 and full intensity maps to 1.0. Each component is then
+multiplied by @code{GL_c_SCALE} and added to @code{GL_c_BIAS}, where
+@var{c} is RED, GREEN, BLUE, or ALPHA. Finally, if @code{GL_MAP_COLOR}
+is @code{GL_TRUE}, each component is clamped to the range @r{[0,1]},
+scaled to the size of its corresponding table, and is then replaced by
+its mapping in the table @code{GL_PIXEL_MAP_c_TO_c}, where @var{c} is R,
+G, B, or A.
+
+Unneeded data is then discarded. For example, @code{GL_RED} discards
+the green, blue, and alpha components, while @code{GL_RGB} discards only
+the alpha component. @code{GL_LUMINANCE} computes a single-component
+value as the sum of the red, green, and blue components, and
@code{GL_LUMINANCE_ALPHA} does the same, while keeping alpha as a second
-value. The final values are clamped to the range @r{[0,1]}.
+value. The final values are clamped to the range @r{[0,1]}.
@end table
The shift, scale, bias, and lookup factors just described are all
-specified by @code{glPixelTransfer}. The lookup table contents
+specified by @code{glPixelTransfer}. The lookup table contents
themselves are specified by @code{glPixelMap}.
Finally, the indices or components are converted to the proper format,
-as specified by @var{type}. If @var{format} is @code{GL_COLOR_INDEX} or
+as specified by @var{type}. If @var{format} is @code{GL_COLOR_INDEX} or
@code{GL_STENCIL_INDEX} and @var{type} is not @code{GL_FLOAT}, each
-index is masked with the mask value given in the following table. If
+index is masked with the mask value given in the following table. If
@var{type} is @code{GL_FLOAT}, then each integer index is converted to
single-precision floating-point format.
@code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA},
@code{GL_BGRA}, @code{GL_LUMINANCE}, or @code{GL_LUMINANCE_ALPHA} and
@var{type} is not @code{GL_FLOAT}, each component is multiplied by the
-multiplier shown in the following table. If type is @code{GL_FLOAT},
+multiplier shown in the following table. If type is @code{GL_FLOAT},
then each component is passed as is (or converted to the client's
single-precision floating-point format if it is different from the one
used by the GL).
@end table
-Return values are placed in memory as follows. If @var{format} is
+Return values are placed in memory as follows. If @var{format} is
@code{GL_COLOR_INDEX}, @code{GL_STENCIL_INDEX},
@code{GL_DEPTH_COMPONENT}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, or @code{GL_LUMINANCE}, a single value
is returned and the data for the @r{@var{i}}th pixel in the
@r{@var{j}}th row is placed in location
-@r{(@var{j},)@var{width}+@var{i}}. @code{GL_RGB} and @code{GL_BGR}
+@r{(@var{j},)@var{width}+@var{i}}. @code{GL_RGB} and @code{GL_BGR}
return three values, @code{GL_RGBA} and @code{GL_BGRA} return four
values, and @code{GL_LUMINANCE_ALPHA} returns two values for each pixel,
with all values corresponding to a single pixel occupying contiguous
-space in @var{data}. Storage parameters set by @code{glPixelStore}, such
-as @code{GL_PACK_LSB_FIRST} and @code{GL_PACK_SWAP_BYTES}, affect the
-way that data is written into memory. See @code{glPixelStore} for a
+space in @var{data}. Storage parameters set by @code{glPixelStore},
+such as @code{GL_PACK_LSB_FIRST} and @code{GL_PACK_SWAP_BYTES}, affect
+the way that data is written into memory. See @code{glPixelStore} for a
description.
@code{GL_INVALID_ENUM} is generated if @var{format} or @var{type} is not
@end table
@code{glRect} supports efficient specification of rectangles as two
-corner points. Each rectangle command takes four arguments, organized
+corner points. Each rectangle command takes four arguments, organized
either as two consecutive pairs of @r{(@var{x},@var{y})} coordinates or
as two pointers to arrays, each containing an @r{(@var{x},@var{y})}
-pair. The resulting rectangle is defined in the @r{@var{z}=0} plane.
+pair. The resulting rectangle is defined in the @r{@var{z}=0} plane.
@code{glRect}(@var{x1}, @var{y1}, @var{x2}, @var{y2}) is exactly
equivalent to the following sequence: Note that if the second vertex is
@table @asis
@item @var{mode}
-Specifies the rasterization mode. Three values are accepted:
-@code{GL_RENDER}, @code{GL_SELECT}, and @code{GL_FEEDBACK}. The initial
+Specifies the rasterization mode. Three values are accepted:
+@code{GL_RENDER}, @code{GL_SELECT}, and @code{GL_FEEDBACK}. The initial
value is @code{GL_RENDER}.
@end table
-@code{glRenderMode} sets the rasterization mode. It takes one argument,
+@code{glRenderMode} sets the rasterization mode. It takes one argument,
@var{mode}, which can assume one of three predefined values:
@table @asis
@item @code{GL_RENDER}
-Render mode. Primitives are rasterized, producing pixel fragments, which
-are written into the frame buffer. This is the normal mode and also the
-default mode.
+Render mode. Primitives are rasterized, producing pixel fragments,
+which are written into the frame buffer. This is the normal mode and
+also the default mode.
@item @code{GL_SELECT}
-Selection mode. No pixel fragments are produced, and no change to the
-frame buffer contents is made. Instead, a record of the names of
+Selection mode. No pixel fragments are produced, and no change to the
+frame buffer contents is made. Instead, a record of the names of
primitives that would have been drawn if the render mode had been
@code{GL_RENDER} is returned in a select buffer, which must be created
(see @code{glSelectBuffer}) before selection mode is entered.
@item @code{GL_FEEDBACK}
-Feedback mode. No pixel fragments are produced, and no change to the
-frame buffer contents is made. Instead, the coordinates and attributes
+Feedback mode. No pixel fragments are produced, and no change to the
+frame buffer contents is made. Instead, the coordinates and attributes
of vertices that would have been drawn if the render mode had been
@code{GL_RENDER} is returned in a feedback buffer, which must be created
(see @code{glFeedbackBuffer}) before feedback mode is entered.
@end table
@code{glRotate} produces a rotation of @var{angle} degrees around the
-vector @r{(@var{x},@var{y}@var{z})}. The current matrix (see
+vector @r{(@var{x},@var{y}@var{z})}. The current matrix (see
@code{glMatrixMode}) is multiplied by a rotation matrix with the product
replacing the current matrix, as if @code{glMultMatrix} were called with
the following matrix as its argument:
If the matrix mode is either @code{GL_MODELVIEW} or
@code{GL_PROJECTION}, all objects drawn after @code{glRotate} is called
-are rotated. Use @code{glPushMatrix} and @code{glPopMatrix} to save and
+are rotated. Use @code{glPushMatrix} and @code{glPopMatrix} to save and
restore the unrotated coordinate system.
@code{GL_INVALID_OPERATION} is generated if @code{glRotate} is executed
@table @asis
@item @var{value}
-Specify a single floating-point sample coverage value. The value is
-clamped to the range @r{[0,1]}. The initial value is 1.0.
+Specify a single floating-point sample coverage value. The value is
+clamped to the range @r{[0,1]}. The initial value is 1.0.
@item @var{invert}
Specify a single boolean value representing if the coverage masks should
-be inverted. @code{GL_TRUE} and @code{GL_FALSE} are accepted. The
+be inverted. @code{GL_TRUE} and @code{GL_FALSE} are accepted. The
initial value is @code{GL_FALSE}.
@end table
Multisampling samples a pixel multiple times at various
implementation-dependent subpixel locations to generate antialiasing
-effects. Multisampling transparently antialiases points, lines,
+effects. Multisampling transparently antialiases points, lines,
polygons, bitmaps, and images if it is enabled.
@var{value} is used in constructing a temporary mask used in determining
-which samples will be used in resolving the final fragment color. This
+which samples will be used in resolving the final fragment color. This
mask is bitwise-anded with the coverage mask generated from the
-multisampling computation. If the @var{invert} flag is set, the
+multisampling computation. If the @var{invert} flag is set, the
temporary mask is inverted (all bits flipped) and then the bitwise-and
is computed.
Provided an implementation supports multisample buffers, and
multisampling is enabled, then a pixel's final color is generated by
-combining several samples per pixel. Each sample contains color, depth,
+combining several samples per pixel. Each sample contains color, depth,
and stencil information, allowing those operations to be performed on
each sample.
@end table
@code{glScale} produces a nonuniform scaling along the @var{x}, @var{y},
-and @var{z} axes. The three parameters indicate the desired scale factor
-along each of the three axes.
+and @var{z} axes. The three parameters indicate the desired scale
+factor along each of the three axes.
The current matrix (see @code{glMatrixMode}) is multiplied by this scale
matrix, and the product replaces the current matrix as if
@table @asis
@item @var{x}
@itemx @var{y}
-Specify the lower left corner of the scissor box. Initially (0, 0).
+Specify the lower left corner of the scissor box. Initially (0, 0).
@item @var{width}
@itemx @var{height}
-Specify the width and height of the scissor box. When a GL context is
+Specify the width and height of the scissor box. When a GL context is
first attached to a window, @var{width} and @var{height} are set to the
dimensions of that window.
@end table
@code{glScissor} defines a rectangle, called the scissor box, in window
-coordinates. The first two arguments, @var{x} and @var{y}, specify the
-lower left corner of the box. @var{width} and @var{height} specify the
+coordinates. The first two arguments, @var{x} and @var{y}, specify the
+lower left corner of the box. @var{width} and @var{height} specify the
width and height of the box.
To enable and disable the scissor test, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_SCISSOR_TEST}. The test is
-initially disabled. While the test is enabled, only pixels that lie
-within the scissor box can be modified by drawing commands. Window
+@code{glDisable} with argument @code{GL_SCISSOR_TEST}. The test is
+initially disabled. While the test is enabled, only pixels that lie
+within the scissor box can be modified by drawing commands. Window
coordinates have integer values at the shared corners of frame buffer
-pixels. @code{glScissor(0,0,1,1)} allows modification of only the lower
+pixels. @code{glScissor(0,0,1,1)} allows modification of only the lower
left pixel in the window, and @code{glScissor(0,0,0,0)} doesn't allow
modification of any pixels in the window.
@table @asis
@item @var{size}
-Specifies the number of components per color. Must be 3.
+Specifies the number of components per color. Must be 3.
@item @var{type}
-Specifies the data type of each color component in the array. Symbolic
+Specifies the data type of each color component in the array. Symbolic
constants @code{GL_BYTE}, @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT},
@code{GL_UNSIGNED_SHORT}, @code{GL_INT}, @code{GL_UNSIGNED_INT},
-@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
+@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
@code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive colors. If @var{stride} is
-0, the colors are understood to be tightly packed in the array. The
+Specifies the byte offset between consecutive colors. If @var{stride}
+is 0, the colors are understood to be tightly packed in the array. The
initial value is 0.
@item @var{pointer}
Specifies a pointer to the first component of the first color element in
-the array. The initial value is 0.
+the array. The initial value is 0.
@end table
@code{glSecondaryColorPointer} specifies the location and data format of
-an array of color components to use when rendering. @var{size} specifies
-the number of components per color, and must be 3. @var{type} specifies
-the data type of each color component, and @var{stride} specifies the
-byte stride from one color to the next, allowing vertices and attributes
-to be packed into a single array or stored in separate arrays.
+an array of color components to use when rendering. @var{size}
+specifies the number of components per color, and must be 3. @var{type}
+specifies the data type of each color component, and @var{stride}
+specifies the byte stride from one color to the next, allowing vertices
+and attributes to be packed into a single array or stored in separate
+arrays.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a secondary color array is
specified, @var{pointer} is treated as a byte offset into the buffer
-object's data store. Also, the buffer object binding
+object's data store. Also, the buffer object binding
(@code{GL_ARRAY_BUFFER_BINDING}) is saved as secondary color vertex
array client-side state
(@code{GL_SECONDARY_COLOR_ARRAY_BUFFER_BINDING}).
To enable and disable the secondary color array, call
@code{glEnableClientState} and @code{glDisableClientState} with the
-argument @code{GL_SECONDARY_COLOR_ARRAY}. If enabled, the secondary
+argument @code{GL_SECONDARY_COLOR_ARRAY}. If enabled, the secondary
color array is used when @code{glArrayElement}, @code{glDrawArrays},
@code{glMultiDrawArrays}, @code{glDrawElements},
@code{glMultiDrawElements}, or @code{glDrawRangeElements} is called.
associated with every vertex.
The secondary color is interpolated and applied to each fragment during
-rasterization when @code{GL_COLOR_SUM} is enabled. When lighting is
+rasterization when @code{GL_COLOR_SUM} is enabled. When lighting is
enabled, and @code{GL_SEPARATE_SPECULAR_COLOR} is specified, the value
of the secondary color is assigned the value computed from the specular
-term of the lighting computation. Both the primary and secondary current
-colors are applied to each fragment, regardless of the state of
-@code{GL_COLOR_SUM}, under such conditions. When
+term of the lighting computation. Both the primary and secondary
+current colors are applied to each fragment, regardless of the state of
+@code{GL_COLOR_SUM}, under such conditions. When
@code{GL_SEPARATE_SPECULAR_COLOR} is specified, the value returned from
querying the current secondary color is undefined.
@code{glSecondaryColor3b}, @code{glSecondaryColor3s}, and
@code{glSecondaryColor3i} take three signed byte, short, or long
-integers as arguments. When @strong{v} is appended to the name, the
+integers as arguments. When @strong{v} is appended to the name, the
color commands can take a pointer to an array of such values.
Color values are stored in floating-point format, with unspecified
-mantissa and exponent sizes. Unsigned integer color components, when
+mantissa and exponent sizes. Unsigned integer color components, when
specified, are linearly mapped to floating-point values such that the
largest representable value maps to 1.0 (full intensity), and 0 maps to
-0.0 (zero intensity). Signed integer color components, when specified,
+0.0 (zero intensity). Signed integer color components, when specified,
are linearly mapped to floating-point values such that the most positive
representable value maps to 1.0, and the most negative representable
-value maps to @r{-1.0}. (Note that this mapping does not convert 0
-precisely to 0.0). Floating-point values are mapped directly.
+value maps to @r{-1.0}. (Note that this mapping does not convert 0
+precisely to 0.0). Floating-point values are mapped directly.
Neither floating-point nor signed integer values are clamped to the
-range @r{[0,1]} before the current color is updated. However, color
+range @r{[0,1]} before the current color is updated. However, color
components are clamped to this range before they are interpolated or
written into a color buffer.
@code{glSelectBuffer} has two arguments: @var{buffer} is a pointer to an
array of unsigned integers, and @var{size} indicates the size of the
-array. @var{buffer} returns values from the name stack (see
+array. @var{buffer} returns values from the name stack (see
@code{glInitNames}, @code{glLoadName}, @code{glPushName}) when the
rendering mode is @code{GL_SELECT} (see @code{glRenderMode}).
@code{glSelectBuffer} must be issued before selection mode is enabled,
and it must not be issued while the rendering mode is @code{GL_SELECT}.
A programmer can use selection to determine which primitives are drawn
-into some region of a window. The region is defined by the current
+into some region of a window. The region is defined by the current
modelview and perspective matrices.
In selection mode, no pixel fragments are produced from rasterization.
Instead, if a primitive or a raster position intersects the clipping
volume defined by the viewing frustum and the user-defined clipping
-planes, this primitive causes a selection hit. (With polygons, no hit
+planes, this primitive causes a selection hit. (With polygons, no hit
occurs if the polygon is culled.) When a change is made to the name
stack, or when @code{glRenderMode} is called, a hit record is copied to
@var{buffer} if any hits have occurred since the last such event (name
-stack change or @code{glRenderMode} call). The hit record consists of
+stack change or @code{glRenderMode} call). The hit record consists of
the number of names in the name stack at the time of the event, followed
by the minimum and maximum depth values of all vertices that hit since
the previous event, followed by the name stack contents, bottom name
@r{2^32-1}, before being placed in the hit record.
An internal index into @var{buffer} is reset to 0 whenever selection
-mode is entered. Each time a hit record is copied into @var{buffer}, the
-index is incremented to point to the cell just past the end of the block
-of names\(emthat is, to the next available cell If the hit record is
-larger than the number of remaining locations in @var{buffer}, as much
-data as can fit is copied, and the overflow flag is set. If the name
-stack is empty when a hit record is copied, that record consists of 0
-followed by the minimum and maximum depth values.
+mode is entered. Each time a hit record is copied into @var{buffer},
+the index is incremented to point to the cell just past the end of the
+block of names\(emthat is, to the next available cell If the hit record
+is larger than the number of remaining locations in @var{buffer}, as
+much data as can fit is copied, and the overflow flag is set. If the
+name stack is empty when a hit record is copied, that record consists of
+0 followed by the minimum and maximum depth values.
To exit selection mode, call @code{glRenderMode} with an argument other
-than @code{GL_SELECT}. Whenever @code{glRenderMode} is called while the
+than @code{GL_SELECT}. Whenever @code{glRenderMode} is called while the
render mode is @code{GL_SELECT}, it returns the number of hit records
copied to @var{buffer}, resets the overflow flag and the selection
-buffer pointer, and initializes the name stack to be empty. If the
+buffer pointer, and initializes the name stack to be empty. If the
overflow bit was set when @code{glRenderMode} was called, a negative hit
record count is returned.
Must be @code{GL_SEPARABLE_2D}.
@item @var{internalformat}
-The internal format of the convolution filter kernel. The allowable
+The internal format of the convolution filter kernel. The allowable
values are @code{GL_ALPHA}, @code{GL_ALPHA4}, @code{GL_ALPHA8},
@code{GL_ALPHA12}, @code{GL_ALPHA16}, @code{GL_LUMINANCE},
@code{GL_LUMINANCE4}, @code{GL_LUMINANCE8}, @code{GL_LUMINANCE12},
@code{GL_RGB10_A2}, @code{GL_RGBA12}, or @code{GL_RGBA16}.
@item @var{width}
-The number of elements in the pixel array referenced by @var{row}. (This
+The number of elements in the pixel array referenced by @var{row}. (This
is the width of the separable filter kernel.)
@item @var{height}
(This is the height of the separable filter kernel.)
@item @var{format}
-The format of the pixel data in @var{row} and @var{column}. The
+The format of the pixel data in @var{row} and @var{column}. The
allowable values are @code{GL_RED}, @code{GL_GREEN}, @code{GL_BLUE},
@code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR}, @code{GL_RGBA},
@code{GL_BGRA}, @code{GL_INTENSITY}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-The type of the pixel data in @var{row} and @var{column}. Symbolic
+The type of the pixel data in @var{row} and @var{column}. Symbolic
constants @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
Next, the R, G, B, and A components of all pixels in both arrays are
scaled by the four separable 2D @code{GL_CONVOLUTION_FILTER_SCALE}
parameters and biased by the four separable 2D
-@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
+@code{GL_CONVOLUTION_FILTER_BIAS} parameters. (The scale and bias
parameters are set by @code{glConvolutionParameter} using the
@code{GL_SEPARABLE_2D} target and the names
@code{GL_CONVOLUTION_FILTER_SCALE} and
-@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are vectors
-of four values that are applied to red, green, blue, and alpha, in that
-order.) The R, G, B, and A values are not clamped to [0,1] at any time
-during this process.
+@code{GL_CONVOLUTION_FILTER_BIAS}. The parameters themselves are
+vectors of four values that are applied to red, green, blue, and alpha,
+in that order.) The R, G, B, and A values are not clamped to [0,1] at
+any time during this process.
Each pixel is then converted to the internal format specified by
-@var{internalformat}. This conversion simply maps the component values
+@var{internalformat}. This conversion simply maps the component values
of the pixel (R, G, B, and A) to the values included in the internal
-format (red, green, blue, alpha, luminance, and intensity). The mapping
+format (red, green, blue, alpha, luminance, and intensity). The mapping
is as follows:
@table @asis
The red, green, blue, alpha, luminance, and/or intensity components of
the resulting pixels are stored in floating-point rather than integer
-format. They form two one-dimensional filter kernel images. The row
+format. They form two one-dimensional filter kernel images. The row
image is indexed by coordinate @var{i} starting at zero and increasing
-from left to right. Each location in the row image is derived from
-element @var{i} of @var{row}. The column image is indexed by coordinate
-@var{j} starting at zero and increasing from bottom to top. Each
+from left to right. Each location in the row image is derived from
+element @var{i} of @var{row}. The column image is indexed by coordinate
+@var{j} starting at zero and increasing from bottom to top. Each
location in the column image is derived from element @var{j} of
@var{column}.
@code{GL_POST_CONVOLUTION_c_SCALE} parameters and biased by their
corresponding @code{GL_POST_CONVOLUTION_c_BIAS} parameters (where
@var{c} takes on the values @strong{RED}, @strong{GREEN}, @strong{BLUE},
-and @strong{ALPHA}). These parameters are set by @code{glPixelTransfer}.
+and @strong{ALPHA}). These parameters are set by
+@code{glPixelTransfer}.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_SEPARABLE_2D}.
allowable values.
@code{GL_INVALID_VALUE} is generated if @var{width} is less than zero or
-greater than the maximum supported value. This value may be queried with
-@code{glGetConvolutionParameter} using target @code{GL_SEPARABLE_2D} and
-name @code{GL_MAX_CONVOLUTION_WIDTH}.
+greater than the maximum supported value. This value may be queried
+with @code{glGetConvolutionParameter} using target
+@code{GL_SEPARABLE_2D} and name @code{GL_MAX_CONVOLUTION_WIDTH}.
@code{GL_INVALID_VALUE} is generated if @var{height} is less than zero
-or greater than the maximum supported value. This value may be queried
+or greater than the maximum supported value. This value may be queried
with @code{glGetConvolutionParameter} using target
@code{GL_SEPARABLE_2D} and name @code{GL_MAX_CONVOLUTION_HEIGHT}.
@table @asis
@item @var{mode}
-Specifies a symbolic value representing a shading technique. Accepted
-values are @code{GL_FLAT} and @code{GL_SMOOTH}. The initial value is
+Specifies a symbolic value representing a shading technique. Accepted
+values are @code{GL_FLAT} and @code{GL_SMOOTH}. The initial value is
@code{GL_SMOOTH}.
@end table
-GL primitives can have either flat or smooth shading. Smooth shading,
+GL primitives can have either flat or smooth shading. Smooth shading,
the default, causes the computed colors of vertices to be interpolated
as the primitive is rasterized, typically assigning different colors to
-each resulting pixel fragment. Flat shading selects the computed color
+each resulting pixel fragment. Flat shading selects the computed color
of just one vertex and assigns it to all the pixel fragments generated
-by rasterizing a single primitive. In either case, the computed color of
-a vertex is the result of lighting if lighting is enabled, or it is the
-current color at the time the vertex was specified if lighting is
+by rasterizing a single primitive. In either case, the computed color
+of a vertex is the result of lighting if lighting is enabled, or it is
+the current color at the time the vertex was specified if lighting is
disabled.
-Flat and smooth shading are indistinguishable for points. Starting when
+Flat and smooth shading are indistinguishable for points. Starting when
@code{glBegin} is issued and counting vertices and primitives from 1,
the GL gives each flat-shaded line segment @r{@var{i}} the computed
-color of vertex @r{@var{i}+1}, its second vertex. Counting similarly
+color of vertex @r{@var{i}+1}, its second vertex. Counting similarly
from 1, the GL gives each flat-shaded polygon the computed color of the
-vertex listed in the following table. This is the last vertex to specify
-the polygon in all cases except single polygons, where the first vertex
-specifies the flat-shaded color.
+vertex listed in the following table. This is the last vertex to
+specify the polygon in all cases except single polygons, where the first
+vertex specifies the flat-shaded color.
@end table
@code{glShaderSource} sets the source code in @var{shader} to the source
-code in the array of strings specified by @var{string}. Any source code
-previously stored in the shader object is completely replaced. The
-number of strings in the array is specified by @var{count}. If
+code in the array of strings specified by @var{string}. Any source code
+previously stored in the shader object is completely replaced. The
+number of strings in the array is specified by @var{count}. If
@var{length} is @code{NULL}, each string is assumed to be null
-terminated. If @var{length} is a value other than @code{NULL}, it points
-to an array containing a string length for each of the corresponding
-elements of @var{string}. Each element in the @var{length} array may
-contain the length of the corresponding string (the null character is
-not counted as part of the string length) or a value less than 0 to
-indicate that the string is null terminated. The source code strings are
-not scanned or parsed at this time; they are simply copied into the
-specified shader object.
+terminated. If @var{length} is a value other than @code{NULL}, it
+points to an array containing a string length for each of the
+corresponding elements of @var{string}. Each element in the
+@var{length} array may contain the length of the corresponding string
+(the null character is not counted as part of the string length) or a
+value less than 0 to indicate that the string is null terminated. The
+source code strings are not scanned or parsed at this time; they are
+simply copied into the specified shader object.
@code{GL_INVALID_VALUE} is generated if @var{shader} is not a value
generated by OpenGL.
@table @asis
@item @var{face}
-Specifies whether front and/or back stencil state is updated. Three
+Specifies whether front and/or back stencil state is updated. Three
symbolic constants are valid: @code{GL_FRONT}, @code{GL_BACK}, and
@code{GL_FRONT_AND_BACK}.
@item @var{func}
-Specifies the test function. Eight symbolic constants are valid:
+Specifies the test function. Eight symbolic constants are valid:
@code{GL_NEVER}, @code{GL_LESS}, @code{GL_LEQUAL}, @code{GL_GREATER},
@code{GL_GEQUAL}, @code{GL_EQUAL}, @code{GL_NOTEQUAL}, and
-@code{GL_ALWAYS}. The initial value is @code{GL_ALWAYS}.
+@code{GL_ALWAYS}. The initial value is @code{GL_ALWAYS}.
@item @var{ref}
-Specifies the reference value for the stencil test. @var{ref} is clamped
-to the range @r{[0,2^@var{n}-1]}, where @r{@var{n}} is the number of
-bitplanes in the stencil buffer. The initial value is 0.
+Specifies the reference value for the stencil test. @var{ref} is
+clamped to the range @r{[0,2^@var{n}-1]}, where @r{@var{n}} is the
+number of bitplanes in the stencil buffer. The initial value is 0.
@item @var{mask}
Specifies a mask that is ANDed with both the reference value and the
-stored stencil value when the test is done. The initial value is all
+stored stencil value when the test is done. The initial value is all
1's.
@end table
Stenciling, like depth-buffering, enables and disables drawing on a
-per-pixel basis. You draw into the stencil planes using GL drawing
+per-pixel basis. You draw into the stencil planes using GL drawing
primitives, then render geometry and images, using the stencil planes to
-mask out portions of the screen. Stenciling is typically used in
+mask out portions of the screen. Stenciling is typically used in
multipass rendering algorithms to achieve special effects, such as
decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome
of a comparison between the reference value and the value in the stencil
-buffer. To enable and disable the test, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_STENCIL_TEST}. To specify
+buffer. To enable and disable the test, call @code{glEnable} and
+@code{glDisable} with argument @code{GL_STENCIL_TEST}. To specify
actions based on the outcome of the stencil test, call
@code{glStencilOp} or @code{glStencilOpSeparate}.
set to @code{GL_FRONT_AND_BACK}.
@var{func} is a symbolic constant that determines the stencil comparison
-function. It accepts one of eight values, shown in the following list.
+function. It accepts one of eight values, shown in the following list.
@var{ref} is an integer reference value that is used in the stencil
-comparison. It is clamped to the range @r{[0,2^@var{n}-1]}, where
-@r{@var{n}} is the number of bitplanes in the stencil buffer. @var{mask}
+comparison. It is clamped to the range @r{[0,2^@var{n}-1]}, where
+@r{@var{n}} is the number of bitplanes in the stencil buffer. @var{mask}
is bitwise ANDed with both the reference value and the stored stencil
value, with the ANDed values participating in the comparison.
If @var{stencil} represents the value stored in the corresponding
stencil buffer location, the following list shows the effect of each
-comparison function that can be specified by @var{func}. Only if the
+comparison function that can be specified by @var{func}. Only if the
comparison succeeds is the pixel passed through to the next stage in the
-rasterization process (see @code{glStencilOp}). All tests treat
+rasterization process (see @code{glStencilOp}). All tests treat
@var{stencil} values as unsigned integers in the range
@r{[0,2^@var{n}-1]}, where @r{@var{n}} is the number of bitplanes in the
stencil buffer.
@table @asis
@item @var{func}
-Specifies the test function. Eight symbolic constants are valid:
+Specifies the test function. Eight symbolic constants are valid:
@code{GL_NEVER}, @code{GL_LESS}, @code{GL_LEQUAL}, @code{GL_GREATER},
@code{GL_GEQUAL}, @code{GL_EQUAL}, @code{GL_NOTEQUAL}, and
-@code{GL_ALWAYS}. The initial value is @code{GL_ALWAYS}.
+@code{GL_ALWAYS}. The initial value is @code{GL_ALWAYS}.
@item @var{ref}
-Specifies the reference value for the stencil test. @var{ref} is clamped
-to the range @r{[0,2^@var{n}-1]}, where @r{@var{n}} is the number of
-bitplanes in the stencil buffer. The initial value is 0.
+Specifies the reference value for the stencil test. @var{ref} is
+clamped to the range @r{[0,2^@var{n}-1]}, where @r{@var{n}} is the
+number of bitplanes in the stencil buffer. The initial value is 0.
@item @var{mask}
Specifies a mask that is ANDed with both the reference value and the
-stored stencil value when the test is done. The initial value is all
+stored stencil value when the test is done. The initial value is all
1's.
@end table
Stenciling, like depth-buffering, enables and disables drawing on a
-per-pixel basis. Stencil planes are first drawn into using GL drawing
+per-pixel basis. Stencil planes are first drawn into using GL drawing
primitives, then geometry and images are rendered using the stencil
-planes to mask out portions of the screen. Stenciling is typically used
+planes to mask out portions of the screen. Stenciling is typically used
in multipass rendering algorithms to achieve special effects, such as
decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome
of a comparison between the reference value and the value in the stencil
-buffer. To enable and disable the test, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_STENCIL_TEST}. To specify
+buffer. To enable and disable the test, call @code{glEnable} and
+@code{glDisable} with argument @code{GL_STENCIL_TEST}. To specify
actions based on the outcome of the stencil test, call
@code{glStencilOp} or @code{glStencilOpSeparate}.
parameters; one affects back-facing polygons, and the other affects
front-facing polygons as well as other non-polygon primitives.
@code{glStencilFunc} sets both front and back stencil state to the same
-values. Use @code{glStencilFuncSeparate} to set front and back stencil
+values. Use @code{glStencilFuncSeparate} to set front and back stencil
state to different values.
@var{func} is a symbolic constant that determines the stencil comparison
-function. It accepts one of eight values, shown in the following list.
+function. It accepts one of eight values, shown in the following list.
@var{ref} is an integer reference value that is used in the stencil
-comparison. It is clamped to the range @r{[0,2^@var{n}-1]}, where
-@r{@var{n}} is the number of bitplanes in the stencil buffer. @var{mask}
+comparison. It is clamped to the range @r{[0,2^@var{n}-1]}, where
+@r{@var{n}} is the number of bitplanes in the stencil buffer. @var{mask}
is bitwise ANDed with both the reference value and the stored stencil
value, with the ANDed values participating in the comparison.
If @var{stencil} represents the value stored in the corresponding
stencil buffer location, the following list shows the effect of each
-comparison function that can be specified by @var{func}. Only if the
+comparison function that can be specified by @var{func}. Only if the
comparison succeeds is the pixel passed through to the next stage in the
-rasterization process (see @code{glStencilOp}). All tests treat
+rasterization process (see @code{glStencilOp}). All tests treat
@var{stencil} values as unsigned integers in the range
@r{[0,2^@var{n}-1]}, where @r{@var{n}} is the number of bitplanes in the
stencil buffer.
@item @var{mask}
Specifies a bit mask to enable and disable writing of individual bits in
-the stencil planes. Initially, the mask is all 1's.
+the stencil planes. Initially, the mask is all 1's.
@end table
@code{glStencilMaskSeparate} controls the writing of individual bits in
-the stencil planes. The least significant @r{@var{n}} bits of
+the stencil planes. The least significant @r{@var{n}} bits of
@var{mask}, where @r{@var{n}} is the number of bits in the stencil
-buffer, specify a mask. Where a 1 appears in the mask, it's possible to
-write to the corresponding bit in the stencil buffer. Where a 0 appears,
-the corresponding bit is write-protected. Initially, all bits are
-enabled for writing.
+buffer, specify a mask. Where a 1 appears in the mask, it's possible to
+write to the corresponding bit in the stencil buffer. Where a 0
+appears, the corresponding bit is write-protected. Initially, all bits
+are enabled for writing.
There can be two separate @var{mask} writemasks; one affects back-facing
polygons, and the other affects front-facing polygons as well as other
-non-polygon primitives. @code{glStencilMask} sets both front and back
+non-polygon primitives. @code{glStencilMask} sets both front and back
stencil writemasks to the same values, as if
@code{glStencilMaskSeparate} were called with @var{face} set to
@code{GL_FRONT_AND_BACK}.
@table @asis
@item @var{mask}
Specifies a bit mask to enable and disable writing of individual bits in
-the stencil planes. Initially, the mask is all 1's.
+the stencil planes. Initially, the mask is all 1's.
@end table
@code{glStencilMask} controls the writing of individual bits in the
-stencil planes. The least significant @r{@var{n}} bits of @var{mask},
+stencil planes. The least significant @r{@var{n}} bits of @var{mask},
where @r{@var{n}} is the number of bits in the stencil buffer, specify a
-mask. Where a 1 appears in the mask, it's possible to write to the
-corresponding bit in the stencil buffer. Where a 0 appears, the
-corresponding bit is write-protected. Initially, all bits are enabled
+mask. Where a 1 appears in the mask, it's possible to write to the
+corresponding bit in the stencil buffer. Where a 0 appears, the
+corresponding bit is write-protected. Initially, all bits are enabled
for writing.
There can be two separate @var{mask} writemasks; one affects back-facing
polygons, and the other affects front-facing polygons as well as other
-non-polygon primitives. @code{glStencilMask} sets both front and back
-stencil writemasks to the same values. Use @code{glStencilMaskSeparate}
+non-polygon primitives. @code{glStencilMask} sets both front and back
+stencil writemasks to the same values. Use @code{glStencilMaskSeparate}
to set front and back stencil writemasks to different values.
@code{GL_INVALID_OPERATION} is generated if @code{glStencilMask} is
@table @asis
@item @var{face}
-Specifies whether front and/or back stencil state is updated. Three
+Specifies whether front and/or back stencil state is updated. Three
symbolic constants are valid: @code{GL_FRONT}, @code{GL_BACK}, and
@code{GL_FRONT_AND_BACK}.
@item @var{sfail}
-Specifies the action to take when the stencil test fails. Eight symbolic
-constants are accepted: @code{GL_KEEP}, @code{GL_ZERO},
+Specifies the action to take when the stencil test fails. Eight
+symbolic constants are accepted: @code{GL_KEEP}, @code{GL_ZERO},
@code{GL_REPLACE}, @code{GL_INCR}, @code{GL_INCR_WRAP}, @code{GL_DECR},
-@code{GL_DECR_WRAP}, and @code{GL_INVERT}. The initial value is
+@code{GL_DECR_WRAP}, and @code{GL_INVERT}. The initial value is
@code{GL_KEEP}.
@item @var{dpfail}
Specifies the stencil action when the stencil test passes, but the depth
-test fails. @var{dpfail} accepts the same symbolic constants as
-@var{sfail}. The initial value is @code{GL_KEEP}.
+test fails. @var{dpfail} accepts the same symbolic constants as
+@var{sfail}. The initial value is @code{GL_KEEP}.
@item @var{dppass}
Specifies the stencil action when both the stencil test and the depth
test pass, or when the stencil test passes and either there is no depth
-buffer or depth testing is not enabled. @var{dppass} accepts the same
-symbolic constants as @var{sfail}. The initial value is @code{GL_KEEP}.
+buffer or depth testing is not enabled. @var{dppass} accepts the same
+symbolic constants as @var{sfail}. The initial value is @code{GL_KEEP}.
@end table
Stenciling, like depth-buffering, enables and disables drawing on a
-per-pixel basis. You draw into the stencil planes using GL drawing
+per-pixel basis. You draw into the stencil planes using GL drawing
primitives, then render geometry and images, using the stencil planes to
-mask out portions of the screen. Stenciling is typically used in
+mask out portions of the screen. Stenciling is typically used in
multipass rendering algorithms to achieve special effects, such as
decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome
of a comparison between the value in the stencil buffer and a reference
-value. To enable and disable the test, call @code{glEnable} and
+value. To enable and disable the test, call @code{glEnable} and
@code{glDisable} with argument @code{GL_STENCIL_TEST}; to control it,
call @code{glStencilFunc} or @code{glStencilFuncSeparate}.
to @code{GL_FRONT_AND_BACK}.
@code{glStencilOpSeparate} takes three arguments that indicate what
-happens to the stored stencil value while stenciling is enabled. If the
+happens to the stored stencil value while stenciling is enabled. If the
stencil test fails, no change is made to the pixel's color or depth
buffers, and @var{sfail} specifies what happens to the stencil buffer
-contents. The following eight actions are possible.
+contents. The following eight actions are possible.
@table @asis
@item @code{GL_KEEP}
@code{glStencilFunc}.
@item @code{GL_INCR}
-Increments the current stencil buffer value. Clamps to the maximum
+Increments the current stencil buffer value. Clamps to the maximum
representable unsigned value.
@item @code{GL_INCR_WRAP}
-Increments the current stencil buffer value. Wraps stencil buffer value
+Increments the current stencil buffer value. Wraps stencil buffer value
to zero when incrementing the maximum representable unsigned value.
@item @code{GL_DECR}
-Decrements the current stencil buffer value. Clamps to 0.
+Decrements the current stencil buffer value. Clamps to 0.
@item @code{GL_DECR_WRAP}
-Decrements the current stencil buffer value. Wraps stencil buffer value
+Decrements the current stencil buffer value. Wraps stencil buffer value
to the maximum representable unsigned value when decrementing a stencil
buffer value of zero.
@end table
-Stencil buffer values are treated as unsigned integers. When incremented
-and decremented, values are clamped to 0 and @r{2^@var{n}-1}, where
-@r{@var{n}} is the value returned by querying @code{GL_STENCIL_BITS}.
+Stencil buffer values are treated as unsigned integers. When
+incremented and decremented, values are clamped to 0 and
+@r{2^@var{n}-1}, where @r{@var{n}} is the value returned by querying
+@code{GL_STENCIL_BITS}.
The other two arguments to @code{glStencilOpSeparate} specify stencil
buffer actions that depend on whether subsequent depth buffer tests
succeed (@var{dppass}) or fail (@var{dpfail}) (see @code{glDepthFunc}).
The actions are specified using the same eight symbolic constants as
-@var{sfail}. Note that @var{dpfail} is ignored when there is no depth
-buffer, or when the depth buffer is not enabled. In these cases,
+@var{sfail}. Note that @var{dpfail} is ignored when there is no depth
+buffer, or when the depth buffer is not enabled. In these cases,
@var{sfail} and @var{dppass} specify stencil action when the stencil
test fails and passes, respectively.
@table @asis
@item @var{sfail}
-Specifies the action to take when the stencil test fails. Eight symbolic
-constants are accepted: @code{GL_KEEP}, @code{GL_ZERO},
+Specifies the action to take when the stencil test fails. Eight
+symbolic constants are accepted: @code{GL_KEEP}, @code{GL_ZERO},
@code{GL_REPLACE}, @code{GL_INCR}, @code{GL_INCR_WRAP}, @code{GL_DECR},
-@code{GL_DECR_WRAP}, and @code{GL_INVERT}. The initial value is
+@code{GL_DECR_WRAP}, and @code{GL_INVERT}. The initial value is
@code{GL_KEEP}.
@item @var{dpfail}
Specifies the stencil action when the stencil test passes, but the depth
-test fails. @var{dpfail} accepts the same symbolic constants as
-@var{sfail}. The initial value is @code{GL_KEEP}.
+test fails. @var{dpfail} accepts the same symbolic constants as
+@var{sfail}. The initial value is @code{GL_KEEP}.
@item @var{dppass}
Specifies the stencil action when both the stencil test and the depth
test pass, or when the stencil test passes and either there is no depth
-buffer or depth testing is not enabled. @var{dppass} accepts the same
-symbolic constants as @var{sfail}. The initial value is @code{GL_KEEP}.
+buffer or depth testing is not enabled. @var{dppass} accepts the same
+symbolic constants as @var{sfail}. The initial value is @code{GL_KEEP}.
@end table
Stenciling, like depth-buffering, enables and disables drawing on a
-per-pixel basis. You draw into the stencil planes using GL drawing
+per-pixel basis. You draw into the stencil planes using GL drawing
primitives, then render geometry and images, using the stencil planes to
-mask out portions of the screen. Stenciling is typically used in
+mask out portions of the screen. Stenciling is typically used in
multipass rendering algorithms to achieve special effects, such as
decals, outlining, and constructive solid geometry rendering.
The stencil test conditionally eliminates a pixel based on the outcome
of a comparison between the value in the stencil buffer and a reference
-value. To enable and disable the test, call @code{glEnable} and
+value. To enable and disable the test, call @code{glEnable} and
@code{glDisable} with argument @code{GL_STENCIL_TEST}; to control it,
call @code{glStencilFunc} or @code{glStencilFuncSeparate}.
@var{dppass} parameters; one affects back-facing polygons, and the other
affects front-facing polygons as well as other non-polygon primitives.
@code{glStencilOp} sets both front and back stencil state to the same
-values. Use @code{glStencilOpSeparate} to set front and back stencil
+values. Use @code{glStencilOpSeparate} to set front and back stencil
state to different values.
@code{glStencilOp} takes three arguments that indicate what happens to
-the stored stencil value while stenciling is enabled. If the stencil
+the stored stencil value while stenciling is enabled. If the stencil
test fails, no change is made to the pixel's color or depth buffers, and
-@var{sfail} specifies what happens to the stencil buffer contents. The
+@var{sfail} specifies what happens to the stencil buffer contents. The
following eight actions are possible.
@table @asis
@code{glStencilFunc}.
@item @code{GL_INCR}
-Increments the current stencil buffer value. Clamps to the maximum
+Increments the current stencil buffer value. Clamps to the maximum
representable unsigned value.
@item @code{GL_INCR_WRAP}
-Increments the current stencil buffer value. Wraps stencil buffer value
+Increments the current stencil buffer value. Wraps stencil buffer value
to zero when incrementing the maximum representable unsigned value.
@item @code{GL_DECR}
-Decrements the current stencil buffer value. Clamps to 0.
+Decrements the current stencil buffer value. Clamps to 0.
@item @code{GL_DECR_WRAP}
-Decrements the current stencil buffer value. Wraps stencil buffer value
+Decrements the current stencil buffer value. Wraps stencil buffer value
to the maximum representable unsigned value when decrementing a stencil
buffer value of zero.
@end table
-Stencil buffer values are treated as unsigned integers. When incremented
-and decremented, values are clamped to 0 and @r{2^@var{n}-1}, where
-@r{@var{n}} is the value returned by querying @code{GL_STENCIL_BITS}.
+Stencil buffer values are treated as unsigned integers. When
+incremented and decremented, values are clamped to 0 and
+@r{2^@var{n}-1}, where @r{@var{n}} is the value returned by querying
+@code{GL_STENCIL_BITS}.
The other two arguments to @code{glStencilOp} specify stencil buffer
actions that depend on whether subsequent depth buffer tests succeed
-(@var{dppass}) or fail (@var{dpfail}) (see @code{glDepthFunc}). The
+(@var{dppass}) or fail (@var{dpfail}) (see @code{glDepthFunc}). The
actions are specified using the same eight symbolic constants as
-@var{sfail}. Note that @var{dpfail} is ignored when there is no depth
-buffer, or when the depth buffer is not enabled. In these cases,
+@var{sfail}. Note that @var{dpfail} is ignored when there is no depth
+buffer, or when the depth buffer is not enabled. In these cases,
@var{sfail} and @var{dppass} specify stencil action when the stencil
test fails and passes, respectively.
@table @asis
@item @var{size}
-Specifies the number of coordinates per array element. Must be 1, 2, 3,
-or 4. The initial value is 4.
+Specifies the number of coordinates per array element. Must be 1, 2, 3,
+or 4. The initial value is 4.
@item @var{type}
-Specifies the data type of each texture coordinate. Symbolic constants
+Specifies the data type of each texture coordinate. Symbolic constants
@code{GL_SHORT}, @code{GL_INT}, @code{GL_FLOAT}, or @code{GL_DOUBLE} are
-accepted. The initial value is @code{GL_FLOAT}.
+accepted. The initial value is @code{GL_FLOAT}.
@item @var{stride}
Specifies the byte offset between consecutive texture coordinate sets.
If @var{stride} is 0, the array elements are understood to be tightly
-packed. The initial value is 0.
+packed. The initial value is 0.
@item @var{pointer}
Specifies a pointer to the first coordinate of the first texture
-coordinate set in the array. The initial value is 0.
+coordinate set in the array. The initial value is 0.
@end table
@code{glTexCoordPointer} specifies the location and data format of an
-array of texture coordinates to use when rendering. @var{size} specifies
-the number of coordinates per texture coordinate set, and must be 1, 2,
-3, or 4. @var{type} specifies the data type of each texture coordinate,
-and @var{stride} specifies the byte stride from one texture coordinate
-set to the next, allowing vertices and attributes to be packed into a
-single array or stored in separate arrays. (Single-array storage may be
-more efficient on some implementations; see @code{glInterleavedArrays}.)
+array of texture coordinates to use when rendering. @var{size}
+specifies the number of coordinates per texture coordinate set, and must
+be 1, 2, 3, or 4. @var{type} specifies the data type of each texture
+coordinate, and @var{stride} specifies the byte stride from one texture
+coordinate set to the next, allowing vertices and attributes to be
+packed into a single array or stored in separate arrays. (Single-array
+storage may be more efficient on some implementations; see
+@code{glInterleavedArrays}.)
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a texture coordinate array is
specified, @var{pointer} is treated as a byte offset into the buffer
-object's data store. Also, the buffer object binding
+object's data store. Also, the buffer object binding
(@code{GL_ARRAY_BUFFER_BINDING}) is saved as texture coordinate vertex
array client-side state (@code{GL_TEXTURE_COORD_ARRAY_BUFFER_BINDING}).
To enable and disable a texture coordinate array, call
@code{glEnableClientState} and @code{glDisableClientState} with the
-argument @code{GL_TEXTURE_COORD_ARRAY}. If enabled, the texture
+argument @code{GL_TEXTURE_COORD_ARRAY}. If enabled, the texture
coordinate array is used when @code{glArrayElement},
@code{glDrawArrays}, @code{glMultiDrawArrays}, @code{glDrawElements},
@code{glMultiDrawElements}, or @code{glDrawRangeElements} is called.
@itemx @var{t}
@itemx @var{r}
@itemx @var{q}
-Specify @var{s}, @var{t}, @var{r}, and @var{q} texture coordinates. Not
+Specify @var{s}, @var{t}, @var{r}, and @var{q} texture coordinates. Not
all parameters are present in all forms of the command.
@end table
@code{glTexCoord} specifies texture coordinates in one, two, three, or
-four dimensions. @code{glTexCoord1} sets the current texture coordinates
-to @r{(@var{s},001)}; a call to @code{glTexCoord2} sets them to
-@r{(@var{s},@var{t}01)}. Similarly, @code{glTexCoord3} specifies the
+four dimensions. @code{glTexCoord1} sets the current texture
+coordinates to @r{(@var{s},001)}; a call to @code{glTexCoord2} sets them
+to @r{(@var{s},@var{t}01)}. Similarly, @code{glTexCoord3} specifies the
texture coordinates as @r{(@var{s},@var{t}@var{r}1)}, and
@code{glTexCoord4} defines all four components explicitly as
@r{(@var{s},@var{t}@var{r}@var{q})}.
The current texture coordinates are part of the data that is associated
-with each vertex and with the current raster position. Initially, the
+with each vertex and with the current raster position. Initially, the
values for @var{s}, @var{t}, @var{r}, and @var{q} are (0, 0, 0, 1).
@table @asis
@item @var{target}
-Specifies a texture environment. May be @code{GL_TEXTURE_ENV},
+Specifies a texture environment. May be @code{GL_TEXTURE_ENV},
@code{GL_TEXTURE_FILTER_CONTROL} or @code{GL_POINT_SPRITE}.
@item @var{pname}
Specifies the symbolic name of a single-valued texture environment
-parameter. May be either @code{GL_TEXTURE_ENV_MODE},
+parameter. May be either @code{GL_TEXTURE_ENV_MODE},
@code{GL_TEXTURE_LOD_BIAS}, @code{GL_COMBINE_RGB},
@code{GL_COMBINE_ALPHA}, @code{GL_SRC0_RGB}, @code{GL_SRC1_RGB},
@code{GL_SRC2_RGB}, @code{GL_SRC0_ALPHA}, @code{GL_SRC1_ALPHA},
@end table
A texture environment specifies how texture values are interpreted when
-a fragment is textured. When @var{target} is
+a fragment is textured. When @var{target} is
@code{GL_TEXTURE_FILTER_CONTROL}, @var{pname} must be
-@code{GL_TEXTURE_LOD_BIAS}. When @var{target} is @code{GL_TEXTURE_ENV},
+@code{GL_TEXTURE_LOD_BIAS}. When @var{target} is @code{GL_TEXTURE_ENV},
@var{pname} can be @code{GL_TEXTURE_ENV_MODE},
@code{GL_TEXTURE_ENV_COLOR}, @code{GL_COMBINE_RGB},
@code{GL_COMBINE_ALPHA}, @code{GL_RGB_SCALE}, @code{GL_ALPHA_SCALE},
@code{GL_SRC0_ALPHA}, @code{GL_SRC1_ALPHA}, or @code{GL_SRC2_ALPHA}.
If @var{pname} is @code{GL_TEXTURE_ENV_MODE}, then @var{params} is (or
-points to) the symbolic name of a texture function. Six texture
+points to) the symbolic name of a texture function. Six texture
functions may be specified: @code{GL_ADD}, @code{GL_MODULATE},
@code{GL_DECAL}, @code{GL_BLEND}, @code{GL_REPLACE}, or
@code{GL_COMBINE}.
The following table shows the correspondence of filtered texture values
@r{@var{R}_@var{t}}, @r{@var{G}_@var{t}}, @r{@var{B}_@var{t}},
@r{@var{A}_@var{t}}, @r{@var{L}_@var{t}}, @r{@var{I}_@var{t}} to texture
-source components. @r{@var{C}_@var{s}} and @r{@var{A}_@var{s}} are used
+source components. @r{@var{C}_@var{s}} and @r{@var{A}_@var{s}} are used
by the texture functions described below.
A texture function acts on the fragment to be textured using the texture
image value that applies to the fragment (see @code{glTexParameter}) and
-produces an RGBA color for that fragment. The following table shows how
+produces an RGBA color for that fragment. The following table shows how
the RGBA color is produced for each of the first five texture functions
-that can be chosen. @r{@var{C}} is a triple of color values (RGB) and
-@r{@var{A}} is the associated alpha value. RGBA values extracted from a
-texture image are in the range [0,1]. The subscript @r{@var{p}} refers
+that can be chosen. @r{@var{C}} is a triple of color values (RGB) and
+@r{@var{A}} is the associated alpha value. RGBA values extracted from a
+texture image are in the range [0,1]. The subscript @r{@var{p}} refers
to the color computed from the previous texture stage (or the incoming
fragment if processing texture stage 0), the subscript @r{@var{s}} to
the texture source color, the subscript @r{@var{c}} to the texture
The following describes how the texture sources, as specified by
@code{GL_SRC0_RGB}, @code{GL_SRC1_RGB}, @code{GL_SRC2_RGB},
@code{GL_SRC0_ALPHA}, @code{GL_SRC1_ALPHA}, and @code{GL_SRC2_ALPHA},
-are combined to produce a final texture color. In the following tables,
+are combined to produce a final texture color. In the following tables,
@code{GL_SRC0_c} is represented by @r{@var{Arg0}}, @code{GL_SRC1_c} is
represented by @r{@var{Arg1}}, and @code{GL_SRC2_c} is represented by
@r{@var{Arg2}}.
Likewise, @code{GL_COMBINE_ALPHA} accepts any of @code{GL_REPLACE},
@code{GL_MODULATE}, @code{GL_ADD}, @code{GL_ADD_SIGNED},
-@code{GL_INTERPOLATE}, or @code{GL_SUBTRACT}. The following table
+@code{GL_INTERPOLATE}, or @code{GL_SUBTRACT}. The following table
describes how alpha values are combined:
and clamped to the range @r{[0,1]}.
If @var{pname} is @code{GL_TEXTURE_ENV_COLOR}, @var{params} is a pointer
-to an array that holds an RGBA color consisting of four values. Integer
+to an array that holds an RGBA color consisting of four values. Integer
color components are interpreted linearly such that the most positive
-integer maps to 1.0, and the most negative integer maps to -1.0. The
+integer maps to 1.0, and the most negative integer maps to -1.0. The
values are clamped to the range [0,1] when they are specified.
@r{@var{C}_@var{c}} takes these four values.
If @var{target} is @code{GL_POINT_SPRITE} and @var{pname} is
@code{GL_COORD_REPLACE}, the boolean value specified is used to either
-enable or disable point sprite texture coordinate replacement. The
+enable or disable point sprite texture coordinate replacement. The
default value is @code{GL_FALSE}.
@code{GL_INVALID_ENUM} is generated when @var{target} or @var{pname} is
@table @asis
@item @var{coord}
-Specifies a texture coordinate. Must be one of @code{GL_S}, @code{GL_T},
-@code{GL_R}, or @code{GL_Q}.
+Specifies a texture coordinate. Must be one of @code{GL_S},
+@code{GL_T}, @code{GL_R}, or @code{GL_Q}.
@item @var{pname}
Specifies the symbolic name of the texture-coordinate generation
-function. Must be @code{GL_TEXTURE_GEN_MODE}.
+function. Must be @code{GL_TEXTURE_GEN_MODE}.
@item @var{param}
Specifies a single-valued texture generation parameter, one of
@end table
@code{glTexGen} selects a texture-coordinate generation function or
-supplies coefficients for one of the functions. @var{coord} names one of
-the (@var{s}, @var{t}, @var{r}, @var{q}) texture coordinates; it must be
-one of the symbols @code{GL_S}, @code{GL_T}, @code{GL_R}, or
-@code{GL_Q}. @var{pname} must be one of three symbolic constants:
+supplies coefficients for one of the functions. @var{coord} names one
+of the (@var{s}, @var{t}, @var{r}, @var{q}) texture coordinates; it must
+be one of the symbols @code{GL_S}, @code{GL_T}, @code{GL_R}, or
+@code{GL_Q}. @var{pname} must be one of three symbolic constants:
@code{GL_TEXTURE_GEN_MODE}, @code{GL_OBJECT_PLANE}, or
-@code{GL_EYE_PLANE}. If @var{pname} is @code{GL_TEXTURE_GEN_MODE}, then
+@code{GL_EYE_PLANE}. If @var{pname} is @code{GL_TEXTURE_GEN_MODE}, then
@var{params} chooses a mode, one of @code{GL_OBJECT_LINEAR},
@code{GL_EYE_LINEAR}, @code{GL_SPHERE_MAP}, @code{GL_NORMAL_MAP}, or
-@code{GL_REFLECTION_MAP}. If @var{pname} is either
+@code{GL_REFLECTION_MAP}. If @var{pname} is either
@code{GL_OBJECT_PLANE} or @code{GL_EYE_PLANE}, @var{params} contains
coefficients for the corresponding texture generation function.
named in @var{coord}, @r{@var{p}_1}, @r{@var{p}_2}, @r{@var{p}_3}, and
@r{@var{p}_4} are the four values supplied in @var{params}, and
@r{@var{x}_@var{o}}, @r{@var{y}_@var{o}}, @r{@var{z}_@var{o}}, and
-@r{@var{w}_@var{o}} are the object coordinates of the vertex. This
+@r{@var{w}_@var{o}} are the object coordinates of the vertex. This
function can be used, for example, to texture-map terrain using sea
level as a reference plane (defined by @r{@var{p}_1}, @r{@var{p}_2},
-@r{@var{p}_3}, and @r{@var{p}_4}). The altitude of a terrain vertex is
+@r{@var{p}_3}, and @r{@var{p}_4}). The altitude of a terrain vertex is
computed by the @code{GL_OBJECT_LINEAR} coordinate generation function
as its distance from sea level; that altitude can then be used to index
the texture image to map white snow onto peaks and green grass onto
@r{@var{w}_@var{e}} are the eye coordinates of the vertex,
@r{@var{p}_1}, @r{@var{p}_2}, @r{@var{p}_3}, and @r{@var{p}_4} are the
values supplied in @var{params}, and @r{@var{M}} is the modelview matrix
-when @code{glTexGen} is invoked. If @r{@var{M}} is poorly conditioned or
-singular, texture coordinates generated by the resulting function may be
-inaccurate or undefined.
+when @code{glTexGen} is invoked. If @r{@var{M}} is poorly conditioned
+or singular, texture coordinates generated by the resulting function may
+be inaccurate or undefined.
Note that the values in @var{params} define a reference plane in eye
-coordinates. The modelview matrix that is applied to them may not be the
-same one in effect when the polygon vertices are transformed. This
+coordinates. The modelview matrix that is applied to them may not be
+the same one in effect when the polygon vertices are transformed. This
function establishes a field of texture coordinates that can produce
dynamic contour lines on moving objects.
If the texture generation function is @code{GL_SPHERE_MAP} and
@var{coord} is either @code{GL_S} or @code{GL_T}, @r{@var{s}} and
-@r{@var{t}} texture coordinates are generated as follows. Let @var{u} be
-the unit vector pointing from the origin to the polygon vertex (in eye
-coordinates). Let @var{n} sup prime be the current normal, after
-transformation to eye coordinates. Let
+@r{@var{t}} texture coordinates are generated as follows. Let @var{u}
+be the unit vector pointing from the origin to the polygon vertex (in
+eye coordinates). Let @var{n} sup prime be the current normal, after
+transformation to eye coordinates. Let
@r{@var{f}=(@var{f}_@var{x}@var{f}_@var{y}@var{f}_@var{z},)^@var{T}}
be the reflection vector such that
@code{glEnable} or @code{glDisable} with one of the symbolic
texture-coordinate names (@code{GL_TEXTURE_GEN_S},
@code{GL_TEXTURE_GEN_T}, @code{GL_TEXTURE_GEN_R}, or
-@code{GL_TEXTURE_GEN_Q}) as the argument. When enabled, the specified
+@code{GL_TEXTURE_GEN_Q}) as the argument. When enabled, the specified
texture coordinate is computed according to the generating function
-associated with that coordinate. When disabled, subsequent vertices take
-the specified texture coordinate from the current set of texture
-coordinates. Initially, all texture generation functions are set to
-@code{GL_EYE_LINEAR} and are disabled. Both @r{@var{s}} plane equations
+associated with that coordinate. When disabled, subsequent vertices
+take the specified texture coordinate from the current set of texture
+coordinates. Initially, all texture generation functions are set to
+@code{GL_EYE_LINEAR} and are disabled. Both @r{@var{s}} plane equations
are (1, 0, 0, 0), both @r{@var{t}} plane equations are (0, 1, 0, 0), and
all @r{@var{r}} and @r{@var{q}} plane equations are (0, 0, 0, 0).
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D} or
+Specifies the target texture. Must be @code{GL_TEXTURE_1D} or
@code{GL_PROXY_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalFormat}
-Specifies the number of color components in the texture. Must be 1, 2,
+Specifies the number of color components in the texture. Must be 1, 2,
3, or 4, or one of the following symbolic constants: @code{GL_ALPHA},
@code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_COMPRESSED_ALPHA},
@code{GL_SRGB_ALPHA}, or @code{GL_SRGB8_ALPHA8}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support texture images that are at least 64 texels wide.
The height of the 1D texture image is 1.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable one-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_1D}.
-Texture images are defined with @code{glTexImage1D}. The arguments
+Texture images are defined with @code{glTexImage1D}. The arguments
describe the parameters of the texture image, such as width, width of
the border, level-of-detail number (see @code{glTexParameter}), and the
-internal resolution and format used to store the image. The last three
+internal resolution and format used to store the image. The last three
arguments describe how the image is represented in memory; they are
identical to the pixel formats used for @code{glDrawPixels}.
for consistency, and checked against the implementation's capabilities.
If the implementation cannot handle a texture of the requested texture
size, it sets all of the image state to 0, but does not generate an
-error (see @code{glGetError}). To query for an entire mipmap array, use
+error (see @code{glGetError}). To query for an entire mipmap array, use
an image array level greater than or equal to 1.
If @var{target} is @code{GL_TEXTURE_1D}, data is read from @var{data} as
a sequence of signed or unsigned bytes, shorts, or longs, or
-single-precision floating-point values, depending on @var{type}. These
+single-precision floating-point values, depending on @var{type}. These
values are grouped into sets of one, two, three, or four values,
-depending on @var{format}, to form elements. If @var{type} is
+depending on @var{format}, to form elements. If @var{type} is
@code{GL_BITMAP}, the data is considered as a string of unsigned bytes
-(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
+(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
treated as eight 1-bit elements, with bit ordering determined by
@code{GL_UNPACK_LSB_FIRST} (see @code{glPixelStore}).
The first element corresponds to the left end of the texture array.
Subsequent elements progress left-to-right through the remaining texels
-in the texture array. The final element corresponds to the right end of
+in the texture array. The final element corresponds to the right end of
the texture array.
@var{format} determines the composition of each element in @var{data}.
@table @asis
@item @code{GL_COLOR_INDEX}
-Each element is a single value, a color index. The GL converts it to
+Each element is a single value, a color index. The GL converts it to
fixed point (with an unspecified number of zero bits to the right of the
binary point), shifted left or right depending on the value and sign of
@code{GL_INDEX_SHIFT}, and added to @code{GL_INDEX_OFFSET} (see
-@code{glPixelTransfer}). The resulting index is converted to a set of
+@code{glPixelTransfer}). The resulting index is converted to a set of
color components using the @code{GL_PIXEL_MAP_I_TO_R},
@code{GL_PIXEL_MAP_I_TO_G}, @code{GL_PIXEL_MAP_I_TO_B}, and
@code{GL_PIXEL_MAP_I_TO_A} tables, and clamped to the range [0,1].
@item @code{GL_RED}
-Each element is a single red component. The GL converts it to floating
+Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and
-blue, and 1 for alpha. Each component is then multiplied by the signed
+blue, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_GREEN}
-Each element is a single green component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red and
-blue, and 1 for alpha. Each component is then multiplied by the signed
-scale factor @code{GL_c_SCALE}, added to the signed bias
+Each element is a single green component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red and blue, and 1 for alpha. Each component is then multiplied by the
+signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_BLUE}
-Each element is a single blue component. The GL converts it to floating
+Each element is a single blue component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for red and
-green, and 1 for alpha. Each component is then multiplied by the signed
+green, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_ALPHA}
-Each element is a single alpha component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red,
-green, and blue. Each component is then multiplied by the signed scale
-factor @code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
-clamped to the range [0,1] (see @code{glPixelTransfer}).
+Each element is a single alpha component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red, green, and blue. Each component is then multiplied by the signed
+scale factor @code{GL_c_SCALE}, added to the signed bias
+@code{GL_c_BIAS}, and clamped to the range [0,1] (see
+@code{glPixelTransfer}).
@item @code{GL_INTENSITY}
-Each element is a single intensity value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-intensity value three times for red, green, blue, and alpha. Each
+Each element is a single intensity value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the intensity value three times for red, green, blue, and alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGB}
@item @code{GL_BGR}
-Each element is an RGB triple. The GL converts it to floating point and
-assembles it into an RGBA element by attaching 1 for alpha. Each
+Each element is an RGB triple. The GL converts it to floating point and
+assembles it into an RGBA element by attaching 1 for alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGBA}
@item @code{GL_BGRA}
-Each element contains all four components. Each component is multiplied
+Each element contains all four components. Each component is multiplied
by the signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_LUMINANCE}
-Each element is a single luminance value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue and attaching 1 for
-alpha. Each component is then multiplied by the signed scale factor
+Each element is a single luminance value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the luminance value three times for red, green, and blue and attaching 1
+for alpha. Each component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_LUMINANCE_ALPHA}
-Each element is a luminance/alpha pair. The GL converts it to floating
+Each element is a luminance/alpha pair. The GL converts it to floating
point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue. Each component is
+luminance value three times for red, green, and blue. Each component is
then multiplied by the signed scale factor @code{GL_c_SCALE}, added to
the signed bias @code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_DEPTH_COMPONENT}
-Each element is a single depth value. The GL converts it to floating
+Each element is a single depth value. The GL converts it to floating
point, multiplies by the signed scale factor @code{GL_DEPTH_SCALE}, adds
the signed bias @code{GL_DEPTH_BIAS}, and clamps to the range [0,1] (see
@code{glPixelTransfer}).
If an application wants to store the texture at a certain resolution or
in a certain format, it can request the resolution and format with
-@var{internalFormat}. The GL will choose an internal representation that
-closely approximates that requested by @var{internalFormat}, but it may
-not match exactly. (The representations specified by
+@var{internalFormat}. The GL will choose an internal representation
+that closely approximates that requested by @var{internalFormat}, but it
+may not match exactly. (The representations specified by
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB}, and
-@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4 may
-also be used to specify the above representations.)
+@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4
+may also be used to specify the above representations.)
If the @var{internalFormat} parameter is one of the generic compressed
formats, @code{GL_COMPRESSED_ALPHA}, @code{GL_COMPRESSED_INTENSITY},
@code{GL_COMPRESSED_LUMINANCE}, @code{GL_COMPRESSED_LUMINANCE_ALPHA},
@code{GL_COMPRESSED_RGB}, or @code{GL_COMPRESSED_RGBA}, the GL will
replace the internal format with the symbolic constant for a specific
-internal format and compress the texture before storage. If no
+internal format and compress the texture before storage. If no
corresponding internal format is available, or the GL can not compress
that image for any reason, the internal format is instead replaced with
a corresponding base internal format.
@code{GL_SLUMINANCE}, @code{GL_SLUMINANCE8}, @code{GL_SLUMINANCE_ALPHA},
or @code{GL_SLUMINANCE8_ALPHA8}, the texture is treated as if the red,
green, blue, or luminance components are encoded in the sRGB color
-space. Any alpha component is left unchanged. The conversion from the
+space. Any alpha component is left unchanged. The conversion from the
sRGB encoded component @r{@var{c}_@var{s}} to a linear component
@r{@var{c}_@var{l}} is:
Assume @r{@var{c}_@var{s}} is the sRGB component in the range [0,1].
Use the @code{GL_PROXY_TEXTURE_1D} target to try out a resolution and
-format. The implementation will update and recompute its best match for
-the requested storage resolution and format. To then query this state,
-call @code{glGetTexLevelParameter}. If the texture cannot be
+format. The implementation will update and recompute its best match for
+the requested storage resolution and format. To then query this state,
+call @code{glGetTexLevelParameter}. If the texture cannot be
accommodated, texture state is set to 0.
A one-component texture image uses only the red component of the RGBA
-color from @var{data}. A two-component image uses the R and A values. A
-three-component image uses the R, G, and B values. A four-component
+color from @var{data}. A two-component image uses the R and A values. A
+three-component image uses the R, G, and B values. A four-component
image uses all of the RGBA components.
Depth textures can be treated as LUMINANCE, INTENSITY or ALPHA textures
-during texture filtering and application. Image-based shadowing can be
+during texture filtering and application. Image-based shadowing can be
enabled by comparing texture r coordinates to depth texture values to
-generate a boolean result. See @code{glTexParameter} for details on
+generate a boolean result. See @code{glTexParameter} for details on
texture comparison.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_TEXTURE_1D} or @code{GL_PROXY_TEXTURE_1D}.
@code{GL_INVALID_ENUM} is generated if @var{format} is not an accepted
-format constant. Format constants other than @code{GL_STENCIL_INDEX} are
-accepted.
+format constant. Format constants other than @code{GL_STENCIL_INDEX}
+are accepted.
@code{GL_INVALID_ENUM} is generated if @var{type} is not a type
constant.
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_PROXY_TEXTURE_2D}, @code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_PROXY_TEXTURE_CUBE_MAP}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{internalFormat}
-Specifies the number of color components in the texture. Must be 1, 2,
+Specifies the number of color components in the texture. Must be 1, 2,
3, or 4, or one of the following symbolic constants: @code{GL_ALPHA},
@code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_COMPRESSED_ALPHA},
@code{GL_SRGB_ALPHA}, or @code{GL_SRGB8_ALPHA8}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support texture images that are at least 64 texels wide.
@item @var{height}
high.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable two-dimensional texturing, call @code{glEnable} and
-@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
+@code{glDisable} with argument @code{GL_TEXTURE_2D}. To enable and
disable texturing using cube-mapped texture, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_CUBE_MAP}.
-To define texture images, call @code{glTexImage2D}. The arguments
+To define texture images, call @code{glTexImage2D}. The arguments
describe the parameters of the texture image, such as height, width,
width of the border, level-of-detail number (see @code{glTexParameter}),
-and number of color components provided. The last three arguments
+and number of color components provided. The last three arguments
describe how the image is represented in memory; they are identical to
the pixel formats used for @code{glDrawPixels}.
If @var{target} is @code{GL_PROXY_TEXTURE_2D} or
@code{GL_PROXY_TEXTURE_CUBE_MAP}, no data is read from @var{data}, but
all of the texture image state is recalculated, checked for consistency,
-and checked against the implementation's capabilities. If the
+and checked against the implementation's capabilities. If the
implementation cannot handle a texture of the requested texture size, it
sets all of the image state to 0, but does not generate an error (see
-@code{glGetError}). To query for an entire mipmap array, use an image
+@code{glGetError}). To query for an entire mipmap array, use an image
array level greater than or equal to 1.
If @var{target} is @code{GL_TEXTURE_2D}, or one of the
@code{GL_TEXTURE_CUBE_MAP} targets, data is read from @var{data} as a
sequence of signed or unsigned bytes, shorts, or longs, or
-single-precision floating-point values, depending on @var{type}. These
+single-precision floating-point values, depending on @var{type}. These
values are grouped into sets of one, two, three, or four values,
-depending on @var{format}, to form elements. If @var{type} is
+depending on @var{format}, to form elements. If @var{type} is
@code{GL_BITMAP}, the data is considered as a string of unsigned bytes
-(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
+(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
treated as eight 1-bit elements, with bit ordering determined by
@code{GL_UNPACK_LSB_FIRST} (see @code{glPixelStore}).
the buffer object's data store.
The first element corresponds to the lower left corner of the texture
-image. Subsequent elements progress left-to-right through the remaining
+image. Subsequent elements progress left-to-right through the remaining
texels in the lowest row of the texture image, and then in successively
-higher rows of the texture image. The final element corresponds to the
+higher rows of the texture image. The final element corresponds to the
upper right corner of the texture image.
@var{format} determines the composition of each element in @var{data}.
@table @asis
@item @code{GL_COLOR_INDEX}
-Each element is a single value, a color index. The GL converts it to
+Each element is a single value, a color index. The GL converts it to
fixed point (with an unspecified number of zero bits to the right of the
binary point), shifted left or right depending on the value and sign of
@code{GL_INDEX_SHIFT}, and added to @code{GL_INDEX_OFFSET} (see
-@code{glPixelTransfer}). The resulting index is converted to a set of
+@code{glPixelTransfer}). The resulting index is converted to a set of
color components using the @code{GL_PIXEL_MAP_I_TO_R},
@code{GL_PIXEL_MAP_I_TO_G}, @code{GL_PIXEL_MAP_I_TO_B}, and
@code{GL_PIXEL_MAP_I_TO_A} tables, and clamped to the range [0,1].
@item @code{GL_RED}
-Each element is a single red component. The GL converts it to floating
+Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and
-blue, and 1 for alpha. Each component is then multiplied by the signed
+blue, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_GREEN}
-Each element is a single green component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red and
-blue, and 1 for alpha. Each component is then multiplied by the signed
-scale factor @code{GL_c_SCALE}, added to the signed bias
+Each element is a single green component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red and blue, and 1 for alpha. Each component is then multiplied by the
+signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_BLUE}
-Each element is a single blue component. The GL converts it to floating
+Each element is a single blue component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for red and
-green, and 1 for alpha. Each component is then multiplied by the signed
+green, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_ALPHA}
-Each element is a single alpha component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red,
-green, and blue. Each component is then multiplied by the signed scale
-factor @code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
-clamped to the range [0,1] (see @code{glPixelTransfer}).
+Each element is a single alpha component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red, green, and blue. Each component is then multiplied by the signed
+scale factor @code{GL_c_SCALE}, added to the signed bias
+@code{GL_c_BIAS}, and clamped to the range [0,1] (see
+@code{glPixelTransfer}).
@item @code{GL_INTENSITY}
-Each element is a single intensity value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-intensity value three times for red, green, blue, and alpha. Each
+Each element is a single intensity value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the intensity value three times for red, green, blue, and alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGB}
@item @code{GL_BGR}
-Each element is an RGB triple. The GL converts it to floating point and
-assembles it into an RGBA element by attaching 1 for alpha. Each
+Each element is an RGB triple. The GL converts it to floating point and
+assembles it into an RGBA element by attaching 1 for alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGBA}
@item @code{GL_BGRA}
-Each element contains all four components. Each component is multiplied
+Each element contains all four components. Each component is multiplied
by the signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_LUMINANCE}
-Each element is a single luminance value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue and attaching 1 for
-alpha. Each component is then multiplied by the signed scale factor
+Each element is a single luminance value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the luminance value three times for red, green, and blue and attaching 1
+for alpha. Each component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_LUMINANCE_ALPHA}
-Each element is a luminance/alpha pair. The GL converts it to floating
+Each element is a luminance/alpha pair. The GL converts it to floating
point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue. Each component is
+luminance value three times for red, green, and blue. Each component is
then multiplied by the signed scale factor @code{GL_c_SCALE}, added to
the signed bias @code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_DEPTH_COMPONENT}
-Each element is a single depth value. The GL converts it to floating
+Each element is a single depth value. The GL converts it to floating
point, multiplies by the signed scale factor @code{GL_DEPTH_SCALE}, adds
the signed bias @code{GL_DEPTH_BIAS}, and clamps to the range [0,1] (see
@code{glPixelTransfer}).
If an application wants to store the texture at a certain resolution or
in a certain format, it can request the resolution and format with
-@var{internalFormat}. The GL will choose an internal representation that
-closely approximates that requested by @var{internalFormat}, but it may
-not match exactly. (The representations specified by
+@var{internalFormat}. The GL will choose an internal representation
+that closely approximates that requested by @var{internalFormat}, but it
+may not match exactly. (The representations specified by
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB}, and
-@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4 may
-also be used to specify the above representations.)
+@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4
+may also be used to specify the above representations.)
If the @var{internalFormat} parameter is one of the generic compressed
formats, @code{GL_COMPRESSED_ALPHA}, @code{GL_COMPRESSED_INTENSITY},
@code{GL_COMPRESSED_LUMINANCE}, @code{GL_COMPRESSED_LUMINANCE_ALPHA},
@code{GL_COMPRESSED_RGB}, or @code{GL_COMPRESSED_RGBA}, the GL will
replace the internal format with the symbolic constant for a specific
-internal format and compress the texture before storage. If no
+internal format and compress the texture before storage. If no
corresponding internal format is available, or the GL can not compress
that image for any reason, the internal format is instead replaced with
a corresponding base internal format.
@code{GL_SLUMINANCE}, @code{GL_SLUMINANCE8}, @code{GL_SLUMINANCE_ALPHA},
or @code{GL_SLUMINANCE8_ALPHA8}, the texture is treated as if the red,
green, blue, or luminance components are encoded in the sRGB color
-space. Any alpha component is left unchanged. The conversion from the
+space. Any alpha component is left unchanged. The conversion from the
sRGB encoded component @r{@var{c}_@var{s}} to a linear component
@r{@var{c}_@var{l}} is:
Assume @r{@var{c}_@var{s}} is the sRGB component in the range [0,1].
Use the @code{GL_PROXY_TEXTURE_2D} or @code{GL_PROXY_TEXTURE_CUBE_MAP}
-target to try out a resolution and format. The implementation will
+target to try out a resolution and format. The implementation will
update and recompute its best match for the requested storage resolution
-and format. To then query this state, call
-@code{glGetTexLevelParameter}. If the texture cannot be accommodated,
+and format. To then query this state, call
+@code{glGetTexLevelParameter}. If the texture cannot be accommodated,
texture state is set to 0.
A one-component texture image uses only the red component of the RGBA
-color extracted from @var{data}. A two-component image uses the R and A
-values. A three-component image uses the R, G, and B values. A
+color extracted from @var{data}. A two-component image uses the R and A
+values. A three-component image uses the R, G, and B values. A
four-component image uses all of the RGBA components.
Depth textures can be treated as LUMINANCE, INTENSITY or ALPHA textures
-during texture filtering and application. Image-based shadowing can be
+during texture filtering and application. Image-based shadowing can be
enabled by comparing texture r coordinates to depth texture values to
-generate a boolean result. See @code{glTexParameter} for details on
+generate a boolean result. See @code{glTexParameter} for details on
texture comparison.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_3D} or
+Specifies the target texture. Must be @code{GL_TEXTURE_3D} or
@code{GL_PROXY_TEXTURE_3D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @r{@var{n}} is the @r{@var{n}^@var{th}} mipmap reduction image.
@item @var{internalFormat}
-Specifies the number of color components in the texture. Must be 1, 2,
+Specifies the number of color components in the texture. Must be 1, 2,
3, or 4, or one of the following symbolic constants: @code{GL_ALPHA},
@code{GL_ALPHA4}, @code{GL_ALPHA8}, @code{GL_ALPHA12},
@code{GL_ALPHA16}, @code{GL_COMPRESSED_ALPHA},
@code{GL_SRGB_ALPHA}, or @code{GL_SRGB8_ALPHA8}.
@item @var{width}
-Specifies the width of the texture image including the border if any. If
+Specifies the width of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
+be @r{2^@var{n}+2(@var{border},)} for some integer @r{@var{n}}. All
implementations support 3D texture images that are at least 16 texels
wide.
texels high.
@item @var{depth}
-Specifies the depth of the texture image including the border if any. If
+Specifies the depth of the texture image including the border if any. If
the GL version does not support non-power-of-two sizes, this value must
-be @r{2^@var{k}+2(@var{border},)} for some integer @r{@var{k}}. All
+be @r{2^@var{k}+2(@var{border},)} for some integer @r{@var{k}}. All
implementations support 3D texture images that are at least 16 texels
deep.
@item @var{border}
-Specifies the width of the border. Must be either 0 or 1.
+Specifies the width of the border. Must be either 0 or 1.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable three-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_3D}.
-To define texture images, call @code{glTexImage3D}. The arguments
+To define texture images, call @code{glTexImage3D}. The arguments
describe the parameters of the texture image, such as height, width,
depth, width of the border, level-of-detail number (see
-@code{glTexParameter}), and number of color components provided. The
+@code{glTexParameter}), and number of color components provided. The
last three arguments describe how the image is represented in memory;
they are identical to the pixel formats used for @code{glDrawPixels}.
for consistency, and checked against the implementation's capabilities.
If the implementation cannot handle a texture of the requested texture
size, it sets all of the image state to 0, but does not generate an
-error (see @code{glGetError}). To query for an entire mipmap array, use
+error (see @code{glGetError}). To query for an entire mipmap array, use
an image array level greater than or equal to 1.
If @var{target} is @code{GL_TEXTURE_3D}, data is read from @var{data} as
a sequence of signed or unsigned bytes, shorts, or longs, or
-single-precision floating-point values, depending on @var{type}. These
+single-precision floating-point values, depending on @var{type}. These
values are grouped into sets of one, two, three, or four values,
-depending on @var{format}, to form elements. If @var{type} is
+depending on @var{format}, to form elements. If @var{type} is
@code{GL_BITMAP}, the data is considered as a string of unsigned bytes
-(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
+(and @var{format} must be @code{GL_COLOR_INDEX}). Each data byte is
treated as eight 1-bit elements, with bit ordering determined by
@code{GL_UNPACK_LSB_FIRST} (see @code{glPixelStore}).
the buffer object's data store.
The first element corresponds to the lower left corner of the texture
-image. Subsequent elements progress left-to-right through the remaining
+image. Subsequent elements progress left-to-right through the remaining
texels in the lowest row of the texture image, and then in successively
-higher rows of the texture image. The final element corresponds to the
+higher rows of the texture image. The final element corresponds to the
upper right corner of the texture image.
@var{format} determines the composition of each element in @var{data}.
@table @asis
@item @code{GL_COLOR_INDEX}
-Each element is a single value, a color index. The GL converts it to
+Each element is a single value, a color index. The GL converts it to
fixed point (with an unspecified number of zero bits to the right of the
binary point), shifted left or right depending on the value and sign of
@code{GL_INDEX_SHIFT}, and added to @code{GL_INDEX_OFFSET} (see
-@code{glPixelTransfer}). The resulting index is converted to a set of
+@code{glPixelTransfer}). The resulting index is converted to a set of
color components using the @code{GL_PIXEL_MAP_I_TO_R},
@code{GL_PIXEL_MAP_I_TO_G}, @code{GL_PIXEL_MAP_I_TO_B}, and
@code{GL_PIXEL_MAP_I_TO_A} tables, and clamped to the range [0,1].
@item @code{GL_RED}
-Each element is a single red component. The GL converts it to floating
+Each element is a single red component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for green and
-blue, and 1 for alpha. Each component is then multiplied by the signed
+blue, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_GREEN}
-Each element is a single green component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red and
-blue, and 1 for alpha. Each component is then multiplied by the signed
-scale factor @code{GL_c_SCALE}, added to the signed bias
+Each element is a single green component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red and blue, and 1 for alpha. Each component is then multiplied by the
+signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_BLUE}
-Each element is a single blue component. The GL converts it to floating
+Each element is a single blue component. The GL converts it to floating
point and assembles it into an RGBA element by attaching 0 for red and
-green, and 1 for alpha. Each component is then multiplied by the signed
+green, and 1 for alpha. Each component is then multiplied by the signed
scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_ALPHA}
-Each element is a single alpha component. The GL converts it to floating
-point and assembles it into an RGBA element by attaching 0 for red,
-green, and blue. Each component is then multiplied by the signed scale
-factor @code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
-clamped to the range [0,1] (see @code{glPixelTransfer}).
+Each element is a single alpha component. The GL converts it to
+floating point and assembles it into an RGBA element by attaching 0 for
+red, green, and blue. Each component is then multiplied by the signed
+scale factor @code{GL_c_SCALE}, added to the signed bias
+@code{GL_c_BIAS}, and clamped to the range [0,1] (see
+@code{glPixelTransfer}).
@item @code{GL_INTENSITY}
-Each element is a single intensity value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-intensity value three times for red, green, blue, and alpha. Each
+Each element is a single intensity value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the intensity value three times for red, green, blue, and alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGB}
@item @code{GL_BGR}
-Each element is an RGB triple. The GL converts it to floating point and
-assembles it into an RGBA element by attaching 1 for alpha. Each
+Each element is an RGB triple. The GL converts it to floating point and
+assembles it into an RGBA element by attaching 1 for alpha. Each
component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_RGBA}
@item @code{GL_BGRA}
-Each element contains all four components. Each component is multiplied
+Each element contains all four components. Each component is multiplied
by the signed scale factor @code{GL_c_SCALE}, added to the signed bias
@code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
@item @code{GL_LUMINANCE}
-Each element is a single luminance value. The GL converts it to floating
-point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue and attaching 1 for
-alpha. Each component is then multiplied by the signed scale factor
+Each element is a single luminance value. The GL converts it to
+floating point, then assembles it into an RGBA element by replicating
+the luminance value three times for red, green, and blue and attaching 1
+for alpha. Each component is then multiplied by the signed scale factor
@code{GL_c_SCALE}, added to the signed bias @code{GL_c_BIAS}, and
clamped to the range [0,1] (see @code{glPixelTransfer}).
@item @code{GL_LUMINANCE_ALPHA}
-Each element is a luminance/alpha pair. The GL converts it to floating
+Each element is a luminance/alpha pair. The GL converts it to floating
point, then assembles it into an RGBA element by replicating the
-luminance value three times for red, green, and blue. Each component is
+luminance value three times for red, green, and blue. Each component is
then multiplied by the signed scale factor @code{GL_c_SCALE}, added to
the signed bias @code{GL_c_BIAS}, and clamped to the range [0,1] (see
@code{glPixelTransfer}).
If an application wants to store the texture at a certain resolution or
in a certain format, it can request the resolution and format with
-@var{internalFormat}. The GL will choose an internal representation that
-closely approximates that requested by @var{internalFormat}, but it may
-not match exactly. (The representations specified by
+@var{internalFormat}. The GL will choose an internal representation
+that closely approximates that requested by @var{internalFormat}, but it
+may not match exactly. (The representations specified by
@code{GL_LUMINANCE}, @code{GL_LUMINANCE_ALPHA}, @code{GL_RGB}, and
-@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4 may
-also be used to specify the above representations.)
+@code{GL_RGBA} must match exactly. The numeric values 1, 2, 3, and 4
+may also be used to specify the above representations.)
If the @var{internalFormat} parameter is one of the generic compressed
formats, @code{GL_COMPRESSED_ALPHA}, @code{GL_COMPRESSED_INTENSITY},
@code{GL_COMPRESSED_LUMINANCE}, @code{GL_COMPRESSED_LUMINANCE_ALPHA},
@code{GL_COMPRESSED_RGB}, or @code{GL_COMPRESSED_RGBA}, the GL will
replace the internal format with the symbolic constant for a specific
-internal format and compress the texture before storage. If no
+internal format and compress the texture before storage. If no
corresponding internal format is available, or the GL can not compress
that image for any reason, the internal format is instead replaced with
a corresponding base internal format.
@code{GL_SLUMINANCE}, @code{GL_SLUMINANCE8}, @code{GL_SLUMINANCE_ALPHA},
or @code{GL_SLUMINANCE8_ALPHA8}, the texture is treated as if the red,
green, blue, or luminance components are encoded in the sRGB color
-space. Any alpha component is left unchanged. The conversion from the
+space. Any alpha component is left unchanged. The conversion from the
sRGB encoded component @r{@var{c}_@var{s}} to a linear component
@r{@var{c}_@var{l}} is:
Assume @r{@var{c}_@var{s}} is the sRGB component in the range [0,1].
Use the @code{GL_PROXY_TEXTURE_3D} target to try out a resolution and
-format. The implementation will update and recompute its best match for
-the requested storage resolution and format. To then query this state,
-call @code{glGetTexLevelParameter}. If the texture cannot be
+format. The implementation will update and recompute its best match for
+the requested storage resolution and format. To then query this state,
+call @code{glGetTexLevelParameter}. If the texture cannot be
accommodated, texture state is set to 0.
A one-component texture image uses only the red component of the RGBA
-color extracted from @var{data}. A two-component image uses the R and A
-values. A three-component image uses the R, G, and B values. A
+color extracted from @var{data}. A two-component image uses the R and A
+values. A three-component image uses the R, G, and B values. A
four-component image uses all of the RGBA components.
@code{GL_INVALID_ENUM} is generated if @var{target} is not
@code{GL_TEXTURE_3D} or @code{GL_PROXY_TEXTURE_3D}.
@code{GL_INVALID_ENUM} is generated if @var{format} is not an accepted
-format constant. Format constants other than @code{GL_STENCIL_INDEX} and
-@code{GL_DEPTH_COMPONENT} are accepted.
+format constant. Format constants other than @code{GL_STENCIL_INDEX}
+and @code{GL_DEPTH_COMPONENT} are accepted.
@code{GL_INVALID_ENUM} is generated if @var{type} is not a type
constant.
@end table
Texture mapping is a technique that applies an image onto an object's
-surface as if the image were a decal or cellophane shrink-wrap. The
+surface as if the image were a decal or cellophane shrink-wrap. The
image is created in texture space, with an (@r{@var{s}}, @r{@var{t}})
-coordinate system. A texture is a one- or two-dimensional image and a
+coordinate system. A texture is a one- or two-dimensional image and a
set of parameters that determine how samples are derived from the image.
@code{glTexParameter} assigns the value or values in @var{params} to the
-texture parameter specified as @var{pname}. @var{target} defines the
+texture parameter specified as @var{pname}. @var{target} defines the
target texture, either @code{GL_TEXTURE_1D}, @code{GL_TEXTURE_2D}, or
-@code{GL_TEXTURE_3D}. The following symbols are accepted in @var{pname}:
+@code{GL_TEXTURE_3D}. The following symbols are accepted in
+@var{pname}:
@table @asis
@item @code{GL_TEXTURE_MIN_FILTER}
The texture minifying function is used whenever the pixel being textured
-maps to an area greater than one texture element. There are six defined
-minifying functions. Two of them use the nearest one or nearest four
-texture elements to compute the texture value. The other four use
+maps to an area greater than one texture element. There are six defined
+minifying functions. Two of them use the nearest one or nearest four
+texture elements to compute the texture value. The other four use
mipmaps.
A mipmap is an ordered set of arrays representing the same image at
-progressively lower resolutions. If the texture has dimensions
+progressively lower resolutions. If the texture has dimensions
@r{2^@var{n}×2^@var{m}}, there are @r{@var{max}(@var{n},@var{m})+1}
-mipmaps. The first mipmap is the original texture, with dimensions
-@r{2^@var{n}×2^@var{m}}. Each subsequent mipmap has dimensions
+mipmaps. The first mipmap is the original texture, with dimensions
+@r{2^@var{n}×2^@var{m}}. Each subsequent mipmap has dimensions
@r{2^@var{k}-1,×2^@var{l}-1,}, where @r{2^@var{k}×2^@var{l}} are the
dimensions of the previous mipmap, until either @r{@var{k}=0} or
-@r{@var{l}=0}. At that point, subsequent mipmaps have dimension
+@r{@var{l}=0}. At that point, subsequent mipmaps have dimension
@r{1×2^@var{l}-1,} or @r{2^@var{k}-1,×1} until the final mipmap, which
-has dimension @r{1×1}. To define the mipmaps, call @code{glTexImage1D},
+has dimension @r{1×1}. To define the mipmaps, call @code{glTexImage1D},
@code{glTexImage2D}, @code{glTexImage3D}, @code{glCopyTexImage1D}, or
@code{glCopyTexImage2D} with the @var{level} argument indicating the
-order of the mipmaps. Level 0 is the original texture; level
+order of the mipmaps. Level 0 is the original texture; level
@r{@var{max}(@var{n},@var{m})} is the final @r{1×1} mipmap.
@var{params} supplies a function for minifying the texture as one of the
following:
As more texture elements are sampled in the minification process, fewer
-aliasing artifacts will be apparent. While the @code{GL_NEAREST} and
+aliasing artifacts will be apparent. While the @code{GL_NEAREST} and
@code{GL_LINEAR} minification functions can be faster than the other
four, they sample only one or four texture elements to determine the
texture value of the pixel being rendered and can produce moire patterns
-or ragged transitions. The initial value of @code{GL_TEXTURE_MIN_FILTER}
-is @code{GL_NEAREST_MIPMAP_LINEAR}.
+or ragged transitions. The initial value of
+@code{GL_TEXTURE_MIN_FILTER} is @code{GL_NEAREST_MIPMAP_LINEAR}.
@item @code{GL_TEXTURE_MAG_FILTER}
The texture magnification function is used when the pixel being textured
-maps to an area less than or equal to one texture element. It sets the
+maps to an area less than or equal to one texture element. It sets the
texture magnification function to either @code{GL_NEAREST} or
-@code{GL_LINEAR} (see below). @code{GL_NEAREST} is generally faster than
-@code{GL_LINEAR}, but it can produce textured images with sharper edges
-because the transition between texture elements is not as smooth. The
-initial value of @code{GL_TEXTURE_MAG_FILTER} is @code{GL_LINEAR}.
+@code{GL_LINEAR} (see below). @code{GL_NEAREST} is generally faster
+than @code{GL_LINEAR}, but it can produce textured images with sharper
+edges because the transition between texture elements is not as smooth.
+The initial value of @code{GL_TEXTURE_MAG_FILTER} is @code{GL_LINEAR}.
@end table
@item @code{GL_LINEAR}
Returns the weighted average of the four texture elements that are
-closest to the center of the pixel being textured. These can include
+closest to the center of the pixel being textured. These can include
border texture elements, depending on the values of
@code{GL_TEXTURE_WRAP_S} and @code{GL_TEXTURE_WRAP_T}, and on the exact
mapping.
Chooses the two mipmaps that most closely match the size of the pixel
being textured and uses the @code{GL_NEAREST} criterion (the texture
element nearest to the center of the pixel) to produce a texture value
-from each mipmap. The final texture value is a weighted average of those
-two values.
+from each mipmap. The final texture value is a weighted average of
+those two values.
@item @code{GL_LINEAR_MIPMAP_LINEAR}
Chooses the two mipmaps that most closely match the size of the pixel
being textured and uses the @code{GL_LINEAR} criterion (a weighted
average of the four texture elements that are closest to the center of
-the pixel) to produce a texture value from each mipmap. The final
+the pixel) to produce a texture value from each mipmap. The final
texture value is a weighted average of those two values.
@end table
@item @code{GL_LINEAR}
Returns the weighted average of the four texture elements that are
-closest to the center of the pixel being textured. These can include
+closest to the center of the pixel being textured. These can include
border texture elements, depending on the values of
@code{GL_TEXTURE_WRAP_S} and @code{GL_TEXTURE_WRAP_T}, and on the exact
mapping.
@table @asis
@item @code{GL_TEXTURE_MIN_LOD}
-Sets the minimum level-of-detail parameter. This floating-point value
+Sets the minimum level-of-detail parameter. This floating-point value
limits the selection of highest resolution mipmap (lowest mipmap level).
The initial value is -1000.
@table @asis
@item @code{GL_TEXTURE_MAX_LOD}
-Sets the maximum level-of-detail parameter. This floating-point value
+Sets the maximum level-of-detail parameter. This floating-point value
limits the selection of the lowest resolution mipmap (highest mipmap
-level). The initial value is 1000.
+level). The initial value is 1000.
@end table
@table @asis
@item @code{GL_TEXTURE_BASE_LEVEL}
-Specifies the index of the lowest defined mipmap level. This is an
-integer value. The initial value is 0.
+Specifies the index of the lowest defined mipmap level. This is an
+integer value. The initial value is 0.
@end table
@table @asis
@item @code{GL_TEXTURE_MAX_LEVEL}
-Sets the index of the highest defined mipmap level. This is an integer
-value. The initial value is 1000.
+Sets the index of the highest defined mipmap level. This is an integer
+value. The initial value is 1000.
@end table
@item @code{GL_TEXTURE_WRAP_S}
Sets the wrap parameter for texture coordinate @r{@var{s}} to either
@code{GL_CLAMP}, @code{GL_CLAMP_TO_BORDER}, @code{GL_CLAMP_TO_EDGE},
-@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. @code{GL_CLAMP} causes
+@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. @code{GL_CLAMP} causes
@r{@var{s}} coordinates to be clamped to the range [0,1] and is useful
for preventing wrapping artifacts when mapping a single image onto an
-object. @code{GL_CLAMP_TO_BORDER} causes the @r{@var{s}} coordinate to
+object. @code{GL_CLAMP_TO_BORDER} causes the @r{@var{s}} coordinate to
be clamped to the range @r{[-1/2@var{N},,1+1/2@var{N},]}, where
@r{@var{N}} is the size of the texture in the direction of
clamping.@code{GL_CLAMP_TO_EDGE} causes @r{@var{s}} coordinates to be
is the size of the texture in the direction of clamping.
@code{GL_REPEAT} causes the integer part of the @r{@var{s}} coordinate
to be ignored; the GL uses only the fractional part, thereby creating a
-repeating pattern. @code{GL_MIRRORED_REPEAT} causes the @r{@var{s}}
+repeating pattern. @code{GL_MIRRORED_REPEAT} causes the @r{@var{s}}
coordinate to be set to the fractional part of the texture coordinate if
the integer part of @r{@var{s}} is even; if the integer part of
@r{@var{s}} is odd, then the @r{@var{s}} texture coordinate is set to
@r{1-@var{frac}(@var{s},)}, where @r{@var{frac}(@var{s},)} represents
-the fractional part of @r{@var{s}}. Border texture elements are accessed
-only if wrapping is set to @code{GL_CLAMP} or @code{GL_CLAMP_TO_BORDER}.
-Initially, @code{GL_TEXTURE_WRAP_S} is set to @code{GL_REPEAT}.
+the fractional part of @r{@var{s}}. Border texture elements are
+accessed only if wrapping is set to @code{GL_CLAMP} or
+@code{GL_CLAMP_TO_BORDER}. Initially, @code{GL_TEXTURE_WRAP_S} is set
+to @code{GL_REPEAT}.
@end table
@item @code{GL_TEXTURE_WRAP_T}
Sets the wrap parameter for texture coordinate @r{@var{t}} to either
@code{GL_CLAMP}, @code{GL_CLAMP_TO_BORDER}, @code{GL_CLAMP_TO_EDGE},
-@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. See the discussion under
-@code{GL_TEXTURE_WRAP_S}. Initially, @code{GL_TEXTURE_WRAP_T} is set to
-@code{GL_REPEAT}.
+@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. See the discussion
+under @code{GL_TEXTURE_WRAP_S}. Initially, @code{GL_TEXTURE_WRAP_T} is
+set to @code{GL_REPEAT}.
@item @code{GL_TEXTURE_WRAP_R}
Sets the wrap parameter for texture coordinate @r{@var{r}} to either
@code{GL_CLAMP}, @code{GL_CLAMP_TO_BORDER}, @code{GL_CLAMP_TO_EDGE},
-@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. See the discussion under
-@code{GL_TEXTURE_WRAP_S}. Initially, @code{GL_TEXTURE_WRAP_R} is set to
-@code{GL_REPEAT}.
+@code{GL_MIRRORED_REPEAT}, or @code{GL_REPEAT}. See the discussion
+under @code{GL_TEXTURE_WRAP_S}. Initially, @code{GL_TEXTURE_WRAP_R} is
+set to @code{GL_REPEAT}.
@item @code{GL_TEXTURE_BORDER_COLOR}
-Sets a border color. @var{params} contains four values that comprise the
-RGBA color of the texture border. Integer color components are
+Sets a border color. @var{params} contains four values that comprise
+the RGBA color of the texture border. Integer color components are
interpreted linearly such that the most positive integer maps to 1.0,
-and the most negative integer maps to -1.0. The values are clamped to
-the range [0,1] when they are specified. Initially, the border color is
+and the most negative integer maps to -1.0. The values are clamped to
+the range [0,1] when they are specified. Initially, the border color is
(0, 0, 0, 0).
@item @code{GL_TEXTURE_PRIORITY}
Specifies the texture residence priority of the currently bound texture.
-Permissible values are in the range @r{[0,1]}. See
+Permissible values are in the range @r{[0,1]}. See
@code{glPrioritizeTextures} and @code{glBindTexture} for more
information.
@item @code{GL_TEXTURE_COMPARE_MODE}
Specifies the texture comparison mode for currently bound depth
-textures. That is, a texture whose internal format is
+textures. That is, a texture whose internal format is
@code{GL_DEPTH_COMPONENT_*}; see @code{glTexImage2D}) Permissible values
are:
@code{GL_TEXTURE_COMPARE_MODE} is set to @code{GL_COMPARE_R_TO_TEXTURE}.
Permissible values are: where @r{@var{r}} is the current interpolated
texture coordinate, and @r{@var{D}_@var{t}} is the depth texture value
-sampled from the currently bound depth texture. @r{@var{result}} is
+sampled from the currently bound depth texture. @r{@var{result}} is
assigned to the either the luminance, intensity, or alpha (as specified
by @code{GL_DEPTH_TEXTURE_MODE}.)
@item @code{GL_DEPTH_TEXTURE_MODE}
Specifies a single symbolic constant indicating how depth values should
-be treated during filtering and texture application. Accepted values are
-@code{GL_LUMINANCE}, @code{GL_INTENSITY}, and @code{GL_ALPHA}. The
+be treated during filtering and texture application. Accepted values
+are @code{GL_LUMINANCE}, @code{GL_INTENSITY}, and @code{GL_ALPHA}. The
initial value is @code{GL_LUMINANCE}.
@item @code{GL_GENERATE_MIPMAP}
Specifies a boolean value that indicates if all levels of a mipmap array
should be automatically updated when any modification to the base level
-mipmap is done. The initial value is @code{GL_FALSE}.
+mipmap is done. The initial value is @code{GL_FALSE}.
@end table
@item @code{GL_COMPARE_R_TO_TEXTURE}
Specifies that the interpolated and clamped @r{@var{r}} texture
coordinate should be compared to the value in the currently bound depth
-texture. See the discussion of @code{GL_TEXTURE_COMPARE_FUNC} for
-details of how the comparison is evaluated. The result of the comparison
-is assigned to luminance, intensity, or alpha (as specified by
-@code{GL_DEPTH_TEXTURE_MODE}).
+texture. See the discussion of @code{GL_TEXTURE_COMPARE_FUNC} for
+details of how the comparison is evaluated. The result of the
+comparison is assigned to luminance, intensity, or alpha (as specified
+by @code{GL_DEPTH_TEXTURE_MODE}).
@item @code{GL_NONE}
Specifies that the luminance, intensity, or alpha (as specified by
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_1D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
Specifies the width of the texture subimage.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable or disable
-one-dimensional texturing, call @code{glEnable} and @code{glDisable}
-with argument @code{GL_TEXTURE_1D}.
+graphical primitive for which texturing is enabled. To enable or
+disable one-dimensional texturing, call @code{glEnable} and
+@code{glDisable} with argument @code{GL_TEXTURE_1D}.
@code{glTexSubImage1D} redefines a contiguous subregion of an existing
-one-dimensional texture image. The texels referenced by @var{data}
+one-dimensional texture image. The texels referenced by @var{data}
replace the portion of the existing texture array with x indices
-@var{xoffset} and @r{@var{xoffset}+@var{width}-1}, inclusive. This
+@var{xoffset} and @r{@var{xoffset}+@var{width}-1}, inclusive. This
region may not include any texels outside the range of the texture array
-as it was originally specified. It is not an error to specify a
+as it was originally specified. It is not an error to specify a
subtexture with width of 0, but such a specification has no effect.
If a non-zero named buffer object is bound to the
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_2D},
+Specifies the target texture. Must be @code{GL_TEXTURE_2D},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_X},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_X},
@code{GL_TEXTURE_CUBE_MAP_POSITIVE_Y},
@code{GL_TEXTURE_CUBE_MAP_NEGATIVE_Z}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
Specifies the height of the texture subimage.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable two-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_2D}.
@code{glTexSubImage2D} redefines a contiguous subregion of an existing
-two-dimensional texture image. The texels referenced by @var{data}
+two-dimensional texture image. The texels referenced by @var{data}
replace the portion of the existing texture array with x indices
@var{xoffset} and @r{@var{xoffset}+@var{width}-1}, inclusive, and y
indices @var{yoffset} and @r{@var{yoffset}+@var{height}-1}, inclusive.
This region may not include any texels outside the range of the texture
-array as it was originally specified. It is not an error to specify a
+array as it was originally specified. It is not an error to specify a
subtexture with zero width or height, but such a specification has no
effect.
@r{(@var{yoffset}+@var{height},)>(@var{h}-@var{b},)}, where @r{@var{w}}
is the @code{GL_TEXTURE_WIDTH}, @r{@var{h}} is the
@code{GL_TEXTURE_HEIGHT}, and @r{@var{b}} is the border width of the
-texture image being modified. Note that @r{@var{w}} and @r{@var{h}}
+texture image being modified. Note that @r{@var{w}} and @r{@var{h}}
include twice the border width.
@code{GL_INVALID_VALUE} is generated if @var{width} or @var{height} is
@table @asis
@item @var{target}
-Specifies the target texture. Must be @code{GL_TEXTURE_3D}.
+Specifies the target texture. Must be @code{GL_TEXTURE_3D}.
@item @var{level}
-Specifies the level-of-detail number. Level 0 is the base image level.
+Specifies the level-of-detail number. Level 0 is the base image level.
Level @var{n} is the @var{n}th mipmap reduction image.
@item @var{xoffset}
Specifies the depth of the texture subimage.
@item @var{format}
-Specifies the format of the pixel data. The following symbolic values
+Specifies the format of the pixel data. The following symbolic values
are accepted: @code{GL_COLOR_INDEX}, @code{GL_RED}, @code{GL_GREEN},
@code{GL_BLUE}, @code{GL_ALPHA}, @code{GL_RGB}, @code{GL_BGR},
@code{GL_RGBA}, @code{GL_BGRA}, @code{GL_LUMINANCE}, and
@code{GL_LUMINANCE_ALPHA}.
@item @var{type}
-Specifies the data type of the pixel data. The following symbolic values
-are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE}, @code{GL_BITMAP},
-@code{GL_UNSIGNED_SHORT}, @code{GL_SHORT}, @code{GL_UNSIGNED_INT},
-@code{GL_INT}, @code{GL_FLOAT}, @code{GL_UNSIGNED_BYTE_3_3_2},
-@code{GL_UNSIGNED_BYTE_2_3_3_REV}, @code{GL_UNSIGNED_SHORT_5_6_5},
-@code{GL_UNSIGNED_SHORT_5_6_5_REV}, @code{GL_UNSIGNED_SHORT_4_4_4_4},
-@code{GL_UNSIGNED_SHORT_4_4_4_4_REV}, @code{GL_UNSIGNED_SHORT_5_5_5_1},
-@code{GL_UNSIGNED_SHORT_1_5_5_5_REV}, @code{GL_UNSIGNED_INT_8_8_8_8},
-@code{GL_UNSIGNED_INT_8_8_8_8_REV}, @code{GL_UNSIGNED_INT_10_10_10_2},
-and @code{GL_UNSIGNED_INT_2_10_10_10_REV}.
+Specifies the data type of the pixel data. The following symbolic
+values are accepted: @code{GL_UNSIGNED_BYTE}, @code{GL_BYTE},
+@code{GL_BITMAP}, @code{GL_UNSIGNED_SHORT}, @code{GL_SHORT},
+@code{GL_UNSIGNED_INT}, @code{GL_INT}, @code{GL_FLOAT},
+@code{GL_UNSIGNED_BYTE_3_3_2}, @code{GL_UNSIGNED_BYTE_2_3_3_REV},
+@code{GL_UNSIGNED_SHORT_5_6_5}, @code{GL_UNSIGNED_SHORT_5_6_5_REV},
+@code{GL_UNSIGNED_SHORT_4_4_4_4}, @code{GL_UNSIGNED_SHORT_4_4_4_4_REV},
+@code{GL_UNSIGNED_SHORT_5_5_5_1}, @code{GL_UNSIGNED_SHORT_1_5_5_5_REV},
+@code{GL_UNSIGNED_INT_8_8_8_8}, @code{GL_UNSIGNED_INT_8_8_8_8_REV},
+@code{GL_UNSIGNED_INT_10_10_10_2}, and
+@code{GL_UNSIGNED_INT_2_10_10_10_REV}.
@item @var{data}
Specifies a pointer to the image data in memory.
@end table
Texturing maps a portion of a specified texture image onto each
-graphical primitive for which texturing is enabled. To enable and
+graphical primitive for which texturing is enabled. To enable and
disable three-dimensional texturing, call @code{glEnable} and
@code{glDisable} with argument @code{GL_TEXTURE_3D}.
@code{glTexSubImage3D} redefines a contiguous subregion of an existing
-three-dimensional texture image. The texels referenced by @var{data}
+three-dimensional texture image. The texels referenced by @var{data}
replace the portion of the existing texture array with x indices
@var{xoffset} and @r{@var{xoffset}+@var{width}-1}, inclusive, y indices
@var{yoffset} and @r{@var{yoffset}+@var{height}-1}, inclusive, and z
indices @var{zoffset} and @r{@var{zoffset}+@var{depth}-1}, inclusive.
This region may not include any texels outside the range of the texture
-array as it was originally specified. It is not an error to specify a
+array as it was originally specified. It is not an error to specify a
subtexture with zero width, height, or depth but such a specification
has no effect.
@end table
@code{glTranslate} produces a translation by
-@r{(@var{x},@var{y}@var{z})}. The current matrix (see
+@r{(@var{x},@var{y}@var{z})}. The current matrix (see
@code{glMatrixMode}) is multiplied by this translation matrix, with the
product replacing the current matrix, as if @code{glMultMatrix} were
called with the following matrix for its argument:
@end table
@code{glUniform} modifies the value of a uniform variable or a uniform
-variable array. The location of the uniform variable to be modified is
+variable array. The location of the uniform variable to be modified is
specified by @var{location}, which should be a value returned by
-@code{glGetUniformLocation}. @code{glUniform} operates on the program
+@code{glGetUniformLocation}. @code{glUniform} operates on the program
object that was made part of current state by calling
@code{glUseProgram}.
The commands @code{glUniform@{1|2|3|4@}@{f|i@}} are used to change the
value of the uniform variable specified by @var{location} using the
-values passed as arguments. The number specified in the command should
+values passed as arguments. The number specified in the command should
match the number of components in the data type of the specified uniform
variable (e.g., @code{1} for float, int, bool; @code{2} for vec2, ivec2,
-bvec2, etc.). The suffix @code{f} indicates that floating-point values
+bvec2, etc.). The suffix @code{f} indicates that floating-point values
are being passed; the suffix @code{i} indicates that integer values are
being passed, and this type should also match the data type of the
-specified uniform variable. The @code{i} variants of this function
+specified uniform variable. The @code{i} variants of this function
should be used to provide values for uniform variables defined as int,
-ivec2, ivec3, ivec4, or arrays of these. The @code{f} variants should be
-used to provide values for uniform variables of type float, vec2, vec3,
-vec4, or arrays of these. Either the @code{i} or the @code{f} variants
-may be used to provide values for uniform variables of type bool, bvec2,
-bvec3, bvec4, or arrays of these. The uniform variable will be set to
-false if the input value is 0 or 0.0f, and it will be set to true
-otherwise.
+ivec2, ivec3, ivec4, or arrays of these. The @code{f} variants should
+be used to provide values for uniform variables of type float, vec2,
+vec3, vec4, or arrays of these. Either the @code{i} or the @code{f}
+variants may be used to provide values for uniform variables of type
+bool, bvec2, bvec3, bvec4, or arrays of these. The uniform variable
+will be set to false if the input value is 0 or 0.0f, and it will be set
+to true otherwise.
All active uniform variables defined in a program object are initialized
-to 0 when the program object is linked successfully. They retain the
+to 0 when the program object is linked successfully. They retain the
values assigned to them by a call to @code{glUniform } until the next
successful link operation occurs on the program object, when they are
once again initialized to 0.
The commands @code{glUniform@{1|2|3|4@}@{f|i@}v} can be used to modify a
-single uniform variable or a uniform variable array. These commands pass
-a count and a pointer to the values to be loaded into a uniform variable
-or a uniform variable array. A count of 1 should be used if modifying
-the value of a single uniform variable, and a count of 1 or greater can
-be used to modify an entire array or part of an array. When loading
-@var{n} elements starting at an arbitrary position @var{m} in a uniform
-variable array, elements @var{m} + @var{n} - 1 in the array will be
-replaced with the new values. If @var{m} + @var{n} - 1 is larger than
-the size of the uniform variable array, values for all array elements
-beyond the end of the array will be ignored. The number specified in the
-name of the command indicates the number of components for each element
-in @var{value}, and it should match the number of components in the data
-type of the specified uniform variable (e.g., @code{1} for float, int,
-bool; @code{2} for vec2, ivec2, bvec2, etc.). The data type specified in
-the name of the command must match the data type for the specified
-uniform variable as described previously for
+single uniform variable or a uniform variable array. These commands
+pass a count and a pointer to the values to be loaded into a uniform
+variable or a uniform variable array. A count of 1 should be used if
+modifying the value of a single uniform variable, and a count of 1 or
+greater can be used to modify an entire array or part of an array. When
+loading @var{n} elements starting at an arbitrary position @var{m} in a
+uniform variable array, elements @var{m} + @var{n} - 1 in the array will
+be replaced with the new values. If @var{m} + @var{n} - 1 is larger
+than the size of the uniform variable array, values for all array
+elements beyond the end of the array will be ignored. The number
+specified in the name of the command indicates the number of components
+for each element in @var{value}, and it should match the number of
+components in the data type of the specified uniform variable (e.g.,
+@code{1} for float, int, bool; @code{2} for vec2, ivec2, bvec2, etc.).
+The data type specified in the name of the command must match the data
+type for the specified uniform variable as described previously for
@code{glUniform@{1|2|3|4@}@{f|i@}}.
For uniform variable arrays, each element of the array is considered to
be of the type indicated in the name of the command (e.g.,
@code{glUniform3f} or @code{glUniform3fv} can be used to load a uniform
-variable array of type vec3). The number of elements of the uniform
+variable array of type vec3). The number of elements of the uniform
variable array to be modified is specified by @var{count}
The commands @code{glUniformMatrix@{2|3|4|2x3|3x2|2x4|4x2|3x4|4x3@}fv}
-are used to modify a matrix or an array of matrices. The numbers in the
-command name are interpreted as the dimensionality of the matrix. The
+are used to modify a matrix or an array of matrices. The numbers in the
+command name are interpreted as the dimensionality of the matrix. The
number @code{2} indicates a 2 × 2 matrix (i.e., 4 values), the number
@code{3} indicates a 3 × 3 matrix (i.e., 9 values), and the number
-@code{4} indicates a 4 × 4 matrix (i.e., 16 values). Non-square matrix
+@code{4} indicates a 4 × 4 matrix (i.e., 16 values). Non-square matrix
dimensionality is explicit, with the first number representing the
number of columns and the second number representing the number of rows.
For example, @code{2x4} indicates a 2 × 4 matrix with 2 columns and 4
-rows (i.e., 8 values). If @var{transpose} is @code{GL_FALSE}, each
-matrix is assumed to be supplied in column major order. If
+rows (i.e., 8 values). If @var{transpose} is @code{GL_FALSE}, each
+matrix is assumed to be supplied in column major order. If
@var{transpose} is @code{GL_TRUE}, each matrix is assumed to be supplied
-in row major order. The @var{count} argument indicates the number of
-matrices to be passed. A count of 1 should be used if modifying the
+in row major order. The @var{count} argument indicates the number of
+matrices to be passed. A count of 1 should be used if modifying the
value of a single matrix, and a count greater than 1 can be used to
modify an array of matrices.
@end table
@code{glUseProgram} installs the program object specified by
-@var{program} as part of current rendering state. One or more
+@var{program} as part of current rendering state. One or more
executables are created in a program object by successfully attaching
shader objects to it with @code{glAttachShader}, successfully compiling
the shader objects with @code{glCompileShader}, and successfully linking
The executable that is installed on the vertex processor is expected to
implement any or all of the desired functionality from the preceding
-list. Similarly, if an executable is installed on the fragment
+list. Similarly, if an executable is installed on the fragment
processor, the OpenGL fixed functionality will be disabled as follows.
@itemize
While a program object is in use, applications are free to modify
attached shader objects, compile attached shader objects, attach
-additional shader objects, and detach or delete shader objects. None of
+additional shader objects, and detach or delete shader objects. None of
these operations will affect the executables that are part of the
-current state. However, relinking the program object that is currently
+current state. However, relinking the program object that is currently
in use will install the program object as part of the current rendering
state if the link operation was successful (see @code{glLinkProgram} ).
If the program object currently in use is relinked unsuccessfully, its
link status will be set to @code{GL_FALSE}, but the executables and
associated state will remain part of the current state until a
-subsequent call to @code{glUseProgram} removes it from use. After it is
+subsequent call to @code{glUseProgram} removes it from use. After it is
removed from use, it cannot be made part of current state until it has
been successfully relinked.
@end table
@code{glValidateProgram} checks to see whether the executables contained
-in @var{program} can execute given the current OpenGL state. The
+in @var{program} can execute given the current OpenGL state. The
information generated by the validation process will be stored in
-@var{program}'s information log. The validation information may consist
+@var{program}'s information log. The validation information may consist
of an empty string, or it may be a string containing information about
how the current program object interacts with the rest of current OpenGL
-state. This provides a way for OpenGL implementers to convey more
+state. This provides a way for OpenGL implementers to convey more
information about why the current program is inefficient, suboptimal,
failing to execute, and so on.
The status of the validation operation will be stored as part of the
-program object's state. This value will be set to @code{GL_TRUE} if the
-validation succeeded, and @code{GL_FALSE} otherwise. It can be queried
+program object's state. This value will be set to @code{GL_TRUE} if the
+validation succeeded, and @code{GL_FALSE} otherwise. It can be queried
by calling @code{glGetProgram} with arguments @var{program} and
-@code{GL_VALIDATE_STATUS}. If validation is successful, @var{program} is
-guaranteed to execute given the current state. Otherwise, @var{program}
-is guaranteed to not execute.
+@code{GL_VALIDATE_STATUS}. If validation is successful, @var{program}
+is guaranteed to execute given the current state. Otherwise,
+@var{program} is guaranteed to not execute.
This function is typically useful only during application development.
The informational string stored in the information log is completely
Specifies the index of the generic vertex attribute to be modified.
@item @var{size}
-Specifies the number of components per generic vertex attribute. Must be
-1, 2, 3, or 4. The initial value is 4.
+Specifies the number of components per generic vertex attribute. Must
+be 1, 2, 3, or 4. The initial value is 4.
@item @var{type}
-Specifies the data type of each component in the array. Symbolic
+Specifies the data type of each component in the array. Symbolic
constants @code{GL_BYTE}, @code{GL_UNSIGNED_BYTE}, @code{GL_SHORT},
@code{GL_UNSIGNED_SHORT}, @code{GL_INT}, @code{GL_UNSIGNED_INT},
-@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
+@code{GL_FLOAT}, or @code{GL_DOUBLE} are accepted. The initial value is
@code{GL_FLOAT}.
@item @var{normalized}
@item @var{stride}
Specifies the byte offset between consecutive generic vertex attributes.
If @var{stride} is 0, the generic vertex attributes are understood to be
-tightly packed in the array. The initial value is 0.
+tightly packed in the array. The initial value is 0.
@item @var{pointer}
Specifies a pointer to the first component of the first generic vertex
-attribute in the array. The initial value is 0.
+attribute in the array. The initial value is 0.
@end table
@code{glVertexAttribPointer} specifies the location and data format of
the array of generic vertex attributes at index @var{index} to use when
-rendering. @var{size} specifies the number of components per attribute
-and must be 1, 2, 3, or 4. @var{type} specifies the data type of each
+rendering. @var{size} specifies the number of components per attribute
+and must be 1, 2, 3, or 4. @var{type} specifies the data type of each
component, and @var{stride} specifies the byte stride from one attribute
to the next, allowing vertices and attributes to be packed into a single
-array or stored in separate arrays. If set to @code{GL_TRUE},
+array or stored in separate arrays. If set to @code{GL_TRUE},
@var{normalized} indicates that values stored in an integer format are
to be mapped to the range [-1,1] (for signed values) or [0,1] (for
unsigned values) when they are accessed and converted to floating point.
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a generic vertex attribute array
is specified, @var{pointer} is treated as a byte offset into the buffer
-object's data store. Also, the buffer object binding
+object's data store. Also, the buffer object binding
(@code{GL_ARRAY_BUFFER_BINDING}) is saved as generic vertex attribute
array client-side state (@code{GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING})
for index @var{index}.
To enable and disable a generic vertex attribute array, call
@code{glEnableVertexAttribArray} and @code{glDisableVertexAttribArray}
-with @var{index}. If enabled, the generic vertex attribute array is used
-when @code{glArrayElement}, @code{glDrawArrays},
+with @var{index}. If enabled, the generic vertex attribute array is
+used when @code{glArrayElement}, @code{glDrawArrays},
@code{glMultiDrawArrays}, @code{glDrawElements},
@code{glMultiDrawElements}, or @code{glDrawRangeElements} is called.
OpenGL defines a number of standard vertex attributes that applications
can modify with standard API entry points (color, normal, texture
-coordinates, etc.). The @code{glVertexAttrib} family of entry points
+coordinates, etc.). The @code{glVertexAttrib} family of entry points
allows an application to pass generic vertex attributes in numbered
locations.
Generic attributes are defined as four-component values that are
-organized into an array. The first entry of this array is numbered 0,
+organized into an array. The first entry of this array is numbered 0,
and the size of the array is specified by the implementation-dependent
-constant @code{GL_MAX_VERTEX_ATTRIBS}. Individual elements of this array
-can be modified with a @code{glVertexAttrib} call that specifies the
-index of the element to be modified and a value for that element.
+constant @code{GL_MAX_VERTEX_ATTRIBS}. Individual elements of this
+array can be modified with a @code{glVertexAttrib} call that specifies
+the index of the element to be modified and a value for that element.
These commands can be used to specify one, two, three, or all four
-components of the generic vertex attribute specified by @var{index}. A
+components of the generic vertex attribute specified by @var{index}. A
@code{1} in the name of the command indicates that only one value is
passed, and it will be used to modify the first component of the generic
-vertex attribute. The second and third components will be set to 0, and
-the fourth component will be set to 1. Similarly, a @code{2} in the name
-of the command indicates that values are provided for the first two
+vertex attribute. The second and third components will be set to 0, and
+the fourth component will be set to 1. Similarly, a @code{2} in the
+name of the command indicates that values are provided for the first two
components, the third component will be set to 0, and the fourth
-component will be set to 1. A @code{3} in the name of the command
+component will be set to 1. A @code{3} in the name of the command
indicates that values are provided for the first three components and
the fourth component will be set to 1, whereas a @code{4} in the name
indicates that values are provided for all four components.
The letters @code{s}, @code{f}, @code{i}, @code{d}, @code{ub},
@code{us}, and @code{ui} indicate whether the arguments are of type
short, float, int, double, unsigned byte, unsigned short, or unsigned
-int. When @code{v} is appended to the name, the commands can take a
-pointer to an array of such values. The commands containing @code{N}
+int. When @code{v} is appended to the name, the commands can take a
+pointer to an array of such values. The commands containing @code{N}
indicate that the arguments will be passed as fixed-point values that
are scaled to a normalized range according to the component conversion
-rules defined by the OpenGL specification. Signed values are understood
+rules defined by the OpenGL specification. Signed values are understood
to represent fixed-point values in the range [-1,1], and unsigned values
are understood to represent fixed-point values in the range [0,1].
OpenGL Shading Language attribute variables are allowed to be of type
-mat2, mat3, or mat4. Attributes of these types may be loaded using the
-@code{glVertexAttrib} entry points. Matrices must be loaded into
+mat2, mat3, or mat4. Attributes of these types may be loaded using the
+@code{glVertexAttrib} entry points. Matrices must be loaded into
successive generic attribute slots in column major order, with one
column of the matrix in each generic attribute slot.
A user-defined attribute variable declared in a vertex shader can be
bound to a generic attribute index by calling
-@code{glBindAttribLocation}. This allows an application to use more
-descriptive variable names in a vertex shader. A subsequent change to
+@code{glBindAttribLocation}. This allows an application to use more
+descriptive variable names in a vertex shader. A subsequent change to
the specified generic vertex attribute will be immediately reflected as
a change to the corresponding attribute variable in the vertex shader.
different program object is used.
An application may freely modify generic vertex attributes that are not
-bound to a named vertex shader attribute variable. These values are
+bound to a named vertex shader attribute variable. These values are
simply maintained as part of current state and will not be accessed by
-the vertex shader. If a generic vertex attribute bound to an attribute
+the vertex shader. If a generic vertex attribute bound to an attribute
variable in a vertex shader is not updated while the vertex shader is
executing, the vertex shader will repeatedly use the current value for
the generic vertex attribute.
The generic vertex attribute with index 0 is the same as the vertex
-position attribute previously defined by OpenGL. A @code{glVertex2},
+position attribute previously defined by OpenGL. A @code{glVertex2},
@code{glVertex3}, or @code{glVertex4} command is completely equivalent
to the corresponding @code{glVertexAttrib} command with an index
-argument of 0. A vertex shader can access generic vertex attribute 0 by
-using the built-in attribute variable @var{gl_Vertex}. There are no
-current values for generic vertex attribute 0. This is the only generic
+argument of 0. A vertex shader can access generic vertex attribute 0 by
+using the built-in attribute variable @var{gl_Vertex}. There are no
+current values for generic vertex attribute 0. This is the only generic
vertex attribute with this property; calls to set other standard vertex
attributes can be freely mixed with calls to set any of the other
generic vertex attributes.
@table @asis
@item @var{size}
-Specifies the number of coordinates per vertex. Must be 2, 3, or 4. The
+Specifies the number of coordinates per vertex. Must be 2, 3, or 4. The
initial value is 4.
@item @var{type}
-Specifies the data type of each coordinate in the array. Symbolic
+Specifies the data type of each coordinate in the array. Symbolic
constants @code{GL_SHORT}, @code{GL_INT}, @code{GL_FLOAT}, or
-@code{GL_DOUBLE} are accepted. The initial value is @code{GL_FLOAT}.
+@code{GL_DOUBLE} are accepted. The initial value is @code{GL_FLOAT}.
@item @var{stride}
-Specifies the byte offset between consecutive vertices. If @var{stride}
-is 0, the vertices are understood to be tightly packed in the array. The
+Specifies the byte offset between consecutive vertices. If @var{stride}
+is 0, the vertices are understood to be tightly packed in the array. The
initial value is 0.
@item @var{pointer}
Specifies a pointer to the first coordinate of the first vertex in the
-array. The initial value is 0.
+array. The initial value is 0.
@end table
@code{glVertexPointer} specifies the location and data format of an
-array of vertex coordinates to use when rendering. @var{size} specifies
-the number of coordinates per vertex, and must be 2, 3, or 4. @var{type}
+array of vertex coordinates to use when rendering. @var{size} specifies
+the number of coordinates per vertex, and must be 2, 3, or 4. @var{type}
specifies the data type of each coordinate, and @var{stride} specifies
the byte stride from one vertex to the next, allowing vertices and
attributes to be packed into a single array or stored in separate
-arrays. (Single-array storage may be more efficient on some
+arrays. (Single-array storage may be more efficient on some
implementations; see @code{glInterleavedArrays}.)
If a non-zero named buffer object is bound to the @code{GL_ARRAY_BUFFER}
target (see @code{glBindBuffer}) while a vertex array is specified,
@var{pointer} is treated as a byte offset into the buffer object's data
-store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
+store. Also, the buffer object binding (@code{GL_ARRAY_BUFFER_BINDING})
is saved as vertex array client-side state
(@code{GL_VERTEX_ARRAY_BUFFER_BINDING}).
To enable and disable the vertex array, call @code{glEnableClientState}
and @code{glDisableClientState} with the argument
-@code{GL_VERTEX_ARRAY}. If enabled, the vertex array is used when
+@code{GL_VERTEX_ARRAY}. If enabled, the vertex array is used when
@code{glArrayElement}, @code{glDrawArrays}, @code{glMultiDrawArrays},
@code{glDrawElements}, @code{glMultiDrawElements}, or
@code{glDrawRangeElements} is called.
@end table
@code{glVertex} commands are used within @code{glBegin}/@code{glEnd}
-pairs to specify point, line, and polygon vertices. The current color,
+pairs to specify point, line, and polygon vertices. The current color,
normal, texture coordinates, and fog coordinate are associated with the
vertex when @code{glVertex} is called.
When only @r{@var{x}} and @r{@var{y}} are specified, @r{@var{z}}
-defaults to 0 and @r{@var{w}} defaults to 1. When @r{@var{x}},
+defaults to 0 and @r{@var{w}} defaults to 1. When @r{@var{x}},
@r{@var{y}}, and @r{@var{z}} are specified, @r{@var{w}} defaults to 1.
@end deftypefun
@table @asis
@item @var{x}
@itemx @var{y}
-Specify the lower left corner of the viewport rectangle, in pixels. The
+Specify the lower left corner of the viewport rectangle, in pixels. The
initial value is (0,0).
@item @var{width}
@itemx @var{height}
-Specify the width and height of the viewport. When a GL context is first
-attached to a window, @var{width} and @var{height} are set to the
+Specify the width and height of the viewport. When a GL context is
+first attached to a window, @var{width} and @var{height} are set to the
dimensions of that window.
@end table
@code{glViewport} specifies the affine transformation of @r{@var{x}} and
@r{@var{y}} from normalized device coordinates to window coordinates.
Let @r{(@var{x}_@var{nd},@var{y}_@var{nd})} be normalized device
-coordinates. Then the window coordinates
+coordinates. Then the window coordinates
@r{(@var{x}_@var{w},@var{y}_@var{w})} are computed as follows:
@r{@var{x}_@var{w}=(@var{x}_@var{nd}+1,)(@var{width}/2,)+@var{x}}
@r{@var{y}_@var{w}=(@var{y}_@var{nd}+1,)(@var{height}/2,)+@var{y}}
Viewport width and height are silently clamped to a range that depends
-on the implementation. To query this range, call @code{glGet} with
+on the implementation. To query this range, call @code{glGet} with
argument @code{GL_MAX_VIEWPORT_DIMS}.
@code{GL_INVALID_VALUE} is generated if either @var{width} or
@end table
-The GL maintains a 3D position in window coordinates. This position,
+The GL maintains a 3D position in window coordinates. This position,
called the raster position, is used to position pixel and bitmap write
-operations. It is maintained with subpixel accuracy. See
+operations. It is maintained with subpixel accuracy. See
@code{glBitmap}, @code{glDrawPixels}, and @code{glCopyPixels}.
@code{glWindowPos2} specifies the @r{@var{x}} and @r{@var{y}}
coordinates, while @r{@var{z}} is implicitly set to 0.
-@code{glWindowPos3} specifies all three coordinates. The @r{@var{w}}
+@code{glWindowPos3} specifies all three coordinates. The @r{@var{w}}
coordinate of the current raster position is always set to 1.0.
@code{glWindowPos} directly updates the @r{@var{x}} and @r{@var{y}}
coordinates of the current raster position with the values specified.
That is, the values are neither transformed by the current modelview and
-projection matrices, nor by the viewport-to-window transform. The
+projection matrices, nor by the viewport-to-window transform. The
@r{@var{z}} coordinate of the current raster position is updated in the
following manner:
where @r{@var{n}} is @code{GL_DEPTH_RANGE}'s near value, and @r{@var{f}}
-is @code{GL_DEPTH_RANGE}'s far value. See @code{glDepthRange}.
+is @code{GL_DEPTH_RANGE}'s far value. See @code{glDepthRange}.
The specified coordinates are not clip-tested, causing the raster
position to always be valid.
The current raster position also includes some associated color data and
-texture coordinates. If lighting is enabled, then
+texture coordinates. If lighting is enabled, then
@code{GL_CURRENT_RASTER_COLOR} (in RGBA mode) or
@code{GL_CURRENT_RASTER_INDEX} (in color index mode) is set to the color
produced by the lighting calculation (see @code{glLight},
-@code{glLightModel}, and @code{glShadeModel}). If lighting is disabled,
+@code{glLightModel}, and @code{glShadeModel}). If lighting is disabled,
current color (in RGBA mode, state variable @code{GL_CURRENT_COLOR}) or
color index (in color index mode, state variable
@code{GL_CURRENT_INDEX}) is used to update the current raster color.
Likewise, @code{GL_CURRENT_RASTER_TEXTURE_COORDS} is updated as a
function of @code{GL_CURRENT_TEXTURE_COORDS}, based on the texture
-matrix and the texture generation functions (see @code{glTexGen}). The
+matrix and the texture generation functions (see @code{glTexGen}). The
@code{GL_CURRENT_RASTER_DISTANCE} is set to the
@code{GL_CURRENT_FOG_COORD}.
HCoop / clinton / guile-figl.git / blobdiff