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3 <?xml-stylesheet type=
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renderer=
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"Content-Type" content=
"text/html; charset=UTF-8" /><title>glCompressedTexImage2D
</title><meta name=
"generator" content=
"DocBook XSL Stylesheets V1.73.2" /></head><body><div class=
"refentry" lang=
"en" xml:
lang=
"en"><a id=
"glCompressedTexImage2D"></a><div class=
"titlepage"></div><div class=
"refnamediv"><h2>Name
</h2><p>glCompressedTexImage2D — specify a two-dimensional texture image in a compressed format
</p></div><div class=
"refsynopsisdiv"><h2>C Specification
</h2><div class=
"funcsynopsis"><table border=
"0" summary=
"Function synopsis" cellspacing=
"0" cellpadding=
"0"><tr><td><code class=
"funcdef">void
<b class=
"fsfunc">glCompressedTexImage2D
</b>(
</code></td><td>GLenum
</td><td><var class=
"pdparam">target
</var>,
</td></tr><tr><td> </td><td>GLint
</td><td><var class=
"pdparam">level
</var>,
</td></tr><tr><td> </td><td>GLenum
</td><td><var class=
"pdparam">internalformat
</var>,
</td></tr><tr><td> </td><td>GLsizei
</td><td><var class=
"pdparam">width
</var>,
</td></tr><tr><td> </td><td>GLsizei
</td><td><var class=
"pdparam">height
</var>,
</td></tr><tr><td> </td><td>GLint
</td><td><var class=
"pdparam">border
</var>,
</td></tr><tr><td> </td><td>GLsizei
</td><td><var class=
"pdparam">imageSize
</var>,
</td></tr><tr><td> </td><td>const GLvoid *
</td><td><var class=
"pdparam">data
</var><code>)
</code>;
</td></tr></table></div></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"parameters"></a><h2>Parameters
</h2><div class=
"variablelist"><dl><dt><span class=
"term"><em class=
"parameter"><code>target
</code></em></span></dt><dd><p>
4 Specifies the target texture.
5 Must be
<code class=
"constant">GL_TEXTURE_2D
</code>,
<code class=
"constant">GL_PROXY_TEXTURE_2D
</code>,
6 <code class=
"constant">GL_TEXTURE_CUBE_MAP_POSITIVE_X
</code>,
7 <code class=
"constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_X
</code>,
8 <code class=
"constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Y
</code>,
9 <code class=
"constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Y
</code>,
10 <code class=
"constant">GL_TEXTURE_CUBE_MAP_POSITIVE_Z
</code>,
11 <code class=
"constant">GL_TEXTURE_CUBE_MAP_NEGATIVE_Z
</code>, or
12 <code class=
"constant">GL_PROXY_TEXTURE_CUBE_MAP
</code>.
13 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>level
</code></em></span></dt><dd><p>
14 Specifies the level-of-detail number.
15 Level
0 is the base image level.
16 Level
<span class=
"emphasis"><em>n
</em></span> is the
<span class=
"emphasis"><em>n
</em></span>th mipmap reduction image.
17 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>internalformat
</code></em></span></dt><dd><p>
18 Specifies the format of the compressed image data stored at address
<em class=
"parameter"><code>data
</code></em>.
19 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>width
</code></em></span></dt><dd><p>
20 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
21 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll">
24 <mml:msup><mml:mn>2</mml:mn>
25 <mml:mi mathvariant=
"italic">n
</mml:mi>
31 <mml:mfenced open=
"(" close=
")">
32 <mml:mi mathvariant=
"italic">border
</mml:mi>
38 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll"><mml:mi mathvariant=
"italic">n
</mml:mi></mml:math>.
40 implementations support
2D texture images that are at least
64 texels
41 wide and cube-mapped texture images that are at least
16 texels wide.
42 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>height
</code></em></span></dt><dd><p>
43 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
45 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll">
48 <mml:msup><mml:mn>2</mml:mn>
49 <mml:mi mathvariant=
"italic">n
</mml:mi>
55 <mml:mfenced open=
"(" close=
")">
56 <mml:mi mathvariant=
"italic">border
</mml:mi>
62 <mml:math xmlns:
mml=
"http://www.w3.org/1998/Math/MathML" overflow=
"scroll"><mml:mi mathvariant=
"italic">n
</mml:mi></mml:math>.
64 implementations support
2D texture images that are at least
64 texels
65 high and cube-mapped texture images that are at least
16 texels high.
66 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>border
</code></em></span></dt><dd><p>
67 Specifies the width of the border.
68 Must be either
0 or
1.
69 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>imageSize
</code></em></span></dt><dd><p>
70 Specifies the number of unsigned bytes of image data starting at the
71 address specified by
<em class=
"parameter"><code>data
</code></em>.
72 </p></dd><dt><span class=
"term"><em class=
"parameter"><code>data
</code></em></span></dt><dd><p>
73 Specifies a pointer to the compressed image data in memory.
74 </p></dd></dl></div></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"description"></a><h2>Description
</h2><p>
75 Texturing maps a portion of a specified texture image onto each graphical
76 primitive for which texturing is enabled. To enable and disable
77 two-dimensional texturing, call
<a class=
"citerefentry" href=
"glEnable.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glEnable
</span></span></a> and
<a class=
"citerefentry" href=
"glDisable.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glDisable
</span></span></a> with argument
78 <code class=
"constant">GL_TEXTURE_2D
</code>. To enable and disable texturing using
79 cube-mapped textures, call
<a class=
"citerefentry" href=
"glEnable.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glEnable
</span></span></a> and
<a class=
"citerefentry" href=
"glDisable.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glDisable
</span></span></a> with argument
80 <code class=
"constant">GL_TEXTURE_CUBE_MAP
</code>.
82 <code class=
"function">glCompressedTexImage2D
</code> loads a previously defined, and retrieved, compressed two-dimensional
83 texture image if
<em class=
"parameter"><code>target
</code></em> is
<code class=
"constant">GL_TEXTURE_2D
</code> (see
<a class=
"citerefentry" href=
"glTexImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexImage2D
</span></span></a>).
85 If
<em class=
"parameter"><code>target
</code></em> is
<code class=
"constant">GL_PROXY_TEXTURE_2D
</code>, no data is read from
<em class=
"parameter"><code>data
</code></em>, but
86 all of the texture image state is recalculated, checked for consistency,
87 and checked against the implementation's capabilities. If the
88 implementation cannot handle a texture of the requested texture size, it
89 sets all of the image state to
0, but does not generate an error (see
90 <a class=
"citerefentry" href=
"glGetError.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetError
</span></span></a>). To query for an entire mipmap array, use an image array level
91 greater than or equal to
1.
93 <em class=
"parameter"><code>internalformat
</code></em> must be an extension-specified compressed-texture format.
94 When a texture is loaded with
<a class=
"citerefentry" href=
"glTexImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexImage2D
</span></span></a> using a generic compressed
95 texture format (e.g.,
<code class=
"constant">GL_COMPRESSED_RGB
</code>), the GL selects from one of
96 its extensions supporting compressed textures. In order to load the
97 compressed texture image using
<code class=
"function">glCompressedTexImage2D
</code>, query the compressed texture image's
98 size and format using
<a class=
"citerefentry" href=
"glGetTexLevelParameter.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetTexLevelParameter
</span></span></a>.
100 If a non-zero named buffer object is bound to the
<code class=
"constant">GL_PIXEL_UNPACK_BUFFER
</code> target
101 (see
<a class=
"citerefentry" href=
"glBindBuffer.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glBindBuffer
</span></span></a>) while a texture image is
102 specified,
<em class=
"parameter"><code>data
</code></em> is treated as a byte offset into the buffer object's data store.
103 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"notes"></a><h2>Notes
</h2><p>
104 <code class=
"function">glCompressedTexImage2D
</code> is available only if the GL version is
1.3 or greater.
106 Non-power-of-two textures are supported if the GL version is
2.0 or greater, or if the implementation exports the
<code class=
"constant">GL_ARB_texture_non_power_of_two
</code> extension.
107 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"errors"></a><h2>Errors
</h2><p>
108 <code class=
"constant">GL_INVALID_ENUM
</code> is generated if
<em class=
"parameter"><code>internalformat
</code></em> is one of the generic compressed internal formats:
<code class=
"constant">GL_COMPRESSED_ALPHA
</code>,
109 <code class=
"constant">GL_COMPRESSED_LUMINANCE
</code>,
<code class=
"constant">GL_COMPRESSED_LUMINANCE_ALPHA
</code>,
110 <code class=
"constant">GL_COMPRESSED_INTENSITY
</code>,
<code class=
"constant">GL_COMPRESSED_RGB
</code>, or
111 <code class=
"constant">GL_COMPRESSED_RGBA
</code>.
113 <code class=
"constant">GL_INVALID_VALUE
</code> is generated if
<em class=
"parameter"><code>imageSize
</code></em> is not consistent with
114 the format, dimensions, and contents of the specified compressed image
117 <code class=
"constant">GL_INVALID_OPERATION
</code> is generated if parameter combinations are not
118 supported by the specific compressed internal format as specified in the
119 specific texture compression extension.
121 <code class=
"constant">GL_INVALID_OPERATION
</code> is generated if a non-zero buffer object name is bound to the
122 <code class=
"constant">GL_PIXEL_UNPACK_BUFFER
</code> target and the buffer object's data store is currently mapped.
124 <code class=
"constant">GL_INVALID_OPERATION
</code> is generated if a non-zero buffer object name is bound to the
125 <code class=
"constant">GL_PIXEL_UNPACK_BUFFER
</code> target and the data would be unpacked from the buffer
126 object such that the memory reads required would exceed the data store size.
128 <code class=
"constant">GL_INVALID_OPERATION
</code> is generated if
<code class=
"function">glCompressedTexImage2D
</code>
129 is executed between the execution of
<a class=
"citerefentry" href=
"glBegin.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glBegin
</span></span></a>
130 and the corresponding execution of
<a class=
"citerefentry" href=
"glEnd.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glEnd
</span></span></a>.
132 Undefined results, including abnormal program termination, are generated if
133 <em class=
"parameter"><code>data
</code></em> is not encoded in a manner consistent with the extension
134 specification defining the internal compression format.
135 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"associatedgets"></a><h2>Associated Gets
</h2><p>
136 <a class=
"citerefentry" href=
"glGetCompressedTexImage.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetCompressedTexImage
</span></span></a>
138 <a class=
"citerefentry" href=
"glGet.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGet
</span></span></a> with argument
<code class=
"constant">GL_TEXTURE_COMPRESSED
</code>
140 <a class=
"citerefentry" href=
"glGet.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGet
</span></span></a> with argument
<code class=
"constant">GL_PIXEL_UNPACK_BUFFER_BINDING
</code>
142 <a class=
"citerefentry" href=
"glGetTexLevelParameter.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glGetTexLevelParameter
</span></span></a> with arguments
<code class=
"constant">GL_TEXTURE_INTERNAL_FORMAT
</code>
143 and
<code class=
"constant">GL_TEXTURE_COMPRESSED_IMAGE_SIZE
</code>
145 <a class=
"citerefentry" href=
"glIsEnabled.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glIsEnabled
</span></span></a> with argument
146 <code class=
"constant">GL_TEXTURE_2D
</code> or
<code class=
"constant">GL_TEXTURE_CUBE_MAP
</code>
147 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"seealso"></a><h2>See Also
</h2><p>
148 <a class=
"citerefentry" href=
"glActiveTexture.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glActiveTexture
</span></span></a>,
149 <a class=
"citerefentry" href=
"glColorTable.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glColorTable
</span></span></a>,
150 <a class=
"citerefentry" href=
"glCompressedTexImage1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCompressedTexImage1D
</span></span></a>,
151 <a class=
"citerefentry" href=
"glCompressedTexImage3D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCompressedTexImage3D
</span></span></a>,
152 <a class=
"citerefentry" href=
"glCompressedTexSubImage1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCompressedTexSubImage1D
</span></span></a>,
153 <a class=
"citerefentry" href=
"glCompressedTexSubImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCompressedTexSubImage2D
</span></span></a>,
154 <a class=
"citerefentry" href=
"glCompressedTexSubImage3D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCompressedTexSubImage3D
</span></span></a>,
155 <a class=
"citerefentry" href=
"glConvolutionFilter1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glConvolutionFilter1D
</span></span></a>,
156 <a class=
"citerefentry" href=
"glCopyPixels.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCopyPixels
</span></span></a>,
157 <a class=
"citerefentry" href=
"glCopyTexImage1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCopyTexImage1D
</span></span></a>,
158 <a class=
"citerefentry" href=
"glCopyTexSubImage1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCopyTexSubImage1D
</span></span></a>,
159 <a class=
"citerefentry" href=
"glCopyTexSubImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCopyTexSubImage2D
</span></span></a>,
160 <a class=
"citerefentry" href=
"glCopyTexSubImage3D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glCopyTexSubImage3D
</span></span></a>,
161 <a class=
"citerefentry" href=
"glDrawPixels.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glDrawPixels
</span></span></a>,
162 <a class=
"citerefentry" href=
"glMatrixMode.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glMatrixMode
</span></span></a>,
163 <a class=
"citerefentry" href=
"glPixelStore.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glPixelStore
</span></span></a>,
164 <a class=
"citerefentry" href=
"glPixelTransfer.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glPixelTransfer
</span></span></a>,
165 <a class=
"citerefentry" href=
"glTexEnv.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexEnv
</span></span></a>,
166 <a class=
"citerefentry" href=
"glTexGen.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexGen
</span></span></a>,
167 <a class=
"citerefentry" href=
"glTexImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexImage2D
</span></span></a>,
168 <a class=
"citerefentry" href=
"glTexImage3D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexImage3D
</span></span></a>,
169 <a class=
"citerefentry" href=
"glTexSubImage1D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexSubImage1D
</span></span></a>,
170 <a class=
"citerefentry" href=
"glTexSubImage2D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexSubImage2D
</span></span></a>,
171 <a class=
"citerefentry" href=
"glTexSubImage3D.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexSubImage3D
</span></span></a>,
172 <a class=
"citerefentry" href=
"glTexParameter.xml"><span class=
"citerefentry"><span class=
"refentrytitle">glTexParameter
</span></span></a>
173 </p></div><div class=
"refsect1" lang=
"en" xml:
lang=
"en"><a id=
"Copyright"></a><h2>Copyright
</h2><p>
174 Copyright
<span class=
"trademark"></span>©
1991-
2006
175 Silicon Graphics, Inc. This document is licensed under the SGI
176 Free Software B License. For details, see
177 <a class=
"ulink" href=
"http://oss.sgi.com/projects/FreeB/" target=
"_top">http://oss.sgi.com/projects/FreeB/
</a>.
178 </p></div></div></body></html>