upstream-doc/man2/glGetPixelMap.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
   3               "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
   4 <refentry id="glGetPixelMap">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetPixelMap</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetPixelMap</refname>
  17         <refpurpose>return the specified pixel map</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetPixelMapfv</function></funcdef>
  23                 <paramdef>GLenum <parameter>map</parameter></paramdef>
  24                 <paramdef>GLfloat * <parameter>data</parameter></paramdef>
  25             </funcprototype>
  26         </funcsynopsis>
  27         <funcsynopsis>
  28             <funcprototype>
  29                 <funcdef>void <function>glGetPixelMapuiv</function></funcdef>
  30                 <paramdef>GLenum <parameter>map</parameter></paramdef>
  31                 <paramdef>GLuint * <parameter>data</parameter></paramdef>
  32             </funcprototype>
  33         </funcsynopsis>
  34         <funcsynopsis>
  35             <funcprototype>
  36                 <funcdef>void <function>glGetPixelMapusv</function></funcdef>
  37                 <paramdef>GLenum <parameter>map</parameter></paramdef>
  38                 <paramdef>GLushort * <parameter>data</parameter></paramdef>
  39             </funcprototype>
  40         </funcsynopsis>
  41     </refsynopsisdiv>
  42     <refsect1 id="parameters"><title>Parameters</title>
  43         <variablelist>
  44         <varlistentry>
  45             <term><parameter>map</parameter></term>
  46             <listitem>
  47                 <para>
  48                     Specifies the name of the pixel map to return.
  49                     Accepted values are
  50                     <constant>GL_PIXEL_MAP_I_TO_I</constant>,
  51                     <constant>GL_PIXEL_MAP_S_TO_S</constant>,
  52                     <constant>GL_PIXEL_MAP_I_TO_R</constant>,
  53                     <constant>GL_PIXEL_MAP_I_TO_G</constant>,
  54                     <constant>GL_PIXEL_MAP_I_TO_B</constant>,
  55                     <constant>GL_PIXEL_MAP_I_TO_A</constant>,
  56                     <constant>GL_PIXEL_MAP_R_TO_R</constant>,
  57                     <constant>GL_PIXEL_MAP_G_TO_G</constant>,
  58                     <constant>GL_PIXEL_MAP_B_TO_B</constant>, and
  59                     <constant>GL_PIXEL_MAP_A_TO_A</constant>.
  60                 </para>
  61             </listitem>
  62         </varlistentry>
  63         <varlistentry>
  64             <term><parameter>data</parameter></term>
  65             <listitem>
  66                 <para>
  67                     Returns the pixel map contents.
  68                 </para>
  69             </listitem>
  70         </varlistentry>
  71         </variablelist>
  72     </refsect1>
  73     <refsect1 id="description"><title>Description</title>
  74         <para>
  75             See the <citerefentry><refentrytitle>glPixelMap</refentrytitle></citerefentry> reference page for a description of the acceptable
  76             values for the <parameter>map</parameter> parameter.
  77             <function>glGetPixelMap</function> returns in <parameter>data</parameter> the contents of the pixel map
  78             specified in <parameter>map</parameter>.
  79             Pixel maps are used during the execution of
  80             <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry>,
  81             <citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>,
  82             <citerefentry><refentrytitle>glCopyPixels</refentrytitle></citerefentry>,
  83             <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>,
  84             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
  85             <citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>,
  86             <citerefentry><refentrytitle>glTexSubImage1D</refentrytitle></citerefentry>,
  87             <citerefentry><refentrytitle>glTexSubImage2D</refentrytitle></citerefentry>,
  88             <citerefentry><refentrytitle>glTexSubImage3D</refentrytitle></citerefentry>,
  89             <citerefentry><refentrytitle>glCopyTexImage1D</refentrytitle></citerefentry>,
  90             <citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>,
  91             <citerefentry><refentrytitle>glCopyTexSubImage1D</refentrytitle></citerefentry>,
  92             <citerefentry><refentrytitle>glCopyTexSubImage2D</refentrytitle></citerefentry>, and
  93             <citerefentry><refentrytitle>glCopyTexSubImage3D</refentrytitle></citerefentry>.
  94             to map color indices,
  95             stencil indices,
  96             color components,
  97             and depth components to other values.
  98         </para>
  99         <para>
 100             If a non-zero named buffer object is bound to the <constant>GL_PIXEL_PACK_BUFFER</constant> target
 101             (see <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>) while a pixel map is
 102             requested, <parameter>data</parameter> is treated as a byte offset into the buffer object's data store.
 103         </para>
 104         <para>
 105             Unsigned integer values,
 106             if requested,
 107             are linearly mapped from the internal fixed or floating-point representation
 108             such that 1.0 maps to the largest representable integer value,
 109             and 0.0 maps to 0.
 110             Return unsigned integer values are undefined if the map value was
 111             not in the range [0,1].
 112         </para>
 113         <para>
 114             To determine the required size of <parameter>map</parameter>,
 115             call <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with the appropriate symbolic
 116             constant.
 117         </para>
 118     </refsect1>
 119     <refsect1 id="notes"><title>Notes</title>
 120         <para>
 121             If an error is generated,
 122             no change is made to the contents of <parameter>data</parameter>.
 123         </para>
 124     </refsect1>
 125     <refsect1 id="errors"><title>Errors</title>
 126         <para>
 127             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>map</parameter> is not an accepted value.
 128         </para>
 129         <para>
 130             <constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to the
 131             <constant>GL_PIXEL_PACK_BUFFER</constant> target and the buffer object's data store is currently mapped.
 132         </para>
 133         <para>
 134             <constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to the
 135             <constant>GL_PIXEL_PACK_BUFFER</constant> target and the data would be packed to the buffer
 136             object such that the memory writes required would exceed the data store size.
 137         </para>
 138         <para>
 139             <constant>GL_INVALID_OPERATION</constant> is generated by <function>glGetPixelMapfv</function> if a non-zero buffer object name is bound to the
 140             <constant>GL_PIXEL_PACK_BUFFER</constant> target and <parameter>data</parameter> is not evenly divisible
 141             into the number of bytes needed to store in memory a GLfloat datum.
 142         </para>
 143         <para>
 144             <constant>GL_INVALID_OPERATION</constant> is generated by <function>glGetPixelMapuiv</function> if a non-zero buffer object name is bound to the
 145             <constant>GL_PIXEL_PACK_BUFFER</constant> target and <parameter>data</parameter> is not evenly divisible
 146             into the number of bytes needed to store in memory a GLuint datum.
 147         </para>
 148         <para>
 149             <constant>GL_INVALID_OPERATION</constant> is generated by <function>glGetPixelMapusv</function> if a non-zero buffer object name is bound to the
 150             <constant>GL_PIXEL_PACK_BUFFER</constant> target and <parameter>data</parameter> is not evenly divisible
 151             into the number of bytes needed to store in memory a GLushort datum.
 152         </para>
 153         <para>
 154             <constant>GL_INVALID_OPERATION</constant> is generated if <function>glGetPixelMap</function>
 155             is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
 156             and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
 157         </para>
 158     </refsect1>
 159     <refsect1 id="associatedgets"><title>Associated Gets</title>
 160         <para>
 161             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_I_TO_I_SIZE</constant>
 162         </para>
 163         <para>
 164             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_S_TO_S_SIZE</constant>
 165         </para>
 166         <para>
 167             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_I_TO_R_SIZE</constant>
 168         </para>
 169         <para>
 170             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_I_TO_G_SIZE</constant>
 171         </para>
 172         <para>
 173             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_I_TO_B_SIZE</constant>
 174         </para>
 175         <para>
 176             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_I_TO_A_SIZE</constant>
 177         </para>
 178         <para>
 179             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_R_TO_R_SIZE</constant>
 180         </para>
 181         <para>
 182             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_G_TO_G_SIZE</constant>
 183         </para>
 184         <para>
 185             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_B_TO_B_SIZE</constant>
 186         </para>
 187         <para>
 188             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_MAP_A_TO_A_SIZE</constant>
 189         </para>
 190         <para>
 191             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_PIXEL_MAP_TABLE</constant>
 192         </para>
 193         <para>
 194             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PIXEL_PACK_BUFFER_BINDING</constant>
 195         </para>
 196     </refsect1>
 197     <refsect1 id="seealso"><title>See Also</title>
 198         <para>
 199             <citerefentry><refentrytitle>glColorSubTable</refentrytitle></citerefentry>,
 200             <citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>,
 201             <citerefentry><refentrytitle>glConvolutionFilter1D</refentrytitle></citerefentry>,
 202             <citerefentry><refentrytitle>glConvolutionFilter2D</refentrytitle></citerefentry>,
 203             <citerefentry><refentrytitle>glCopyColorSubTable</refentrytitle></citerefentry>,
 204             <citerefentry><refentrytitle>glCopyColorTable</refentrytitle></citerefentry>,
 205             <citerefentry><refentrytitle>glCopyPixels</refentrytitle></citerefentry>,
 206             <citerefentry><refentrytitle>glCopyTexImage1D</refentrytitle></citerefentry>,
 207             <citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>,
 208             <citerefentry><refentrytitle>glCopyTexSubImage1D</refentrytitle></citerefentry>,
 209             <citerefentry><refentrytitle>glCopyTexSubImage2D</refentrytitle></citerefentry>,
 210             <citerefentry><refentrytitle>glCopyTexSubImage3D</refentrytitle></citerefentry>,
 211             <citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>,
 212             <citerefentry><refentrytitle>glGetHistogram</refentrytitle></citerefentry>,
 213             <citerefentry><refentrytitle>glGetMinmax</refentrytitle></citerefentry>,
 214             <citerefentry><refentrytitle>glGetTexImage</refentrytitle></citerefentry>,
 215             <citerefentry><refentrytitle>glPixelMap</refentrytitle></citerefentry>,
 216             <citerefentry><refentrytitle>glPixelTransfer</refentrytitle></citerefentry>,
 217             <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry>,
 218             <citerefentry><refentrytitle>glSeparableFilter2D</refentrytitle></citerefentry>,
 219             <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>,
 220             <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>,
 221             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>
 222             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
 223             <citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>,
 224             <citerefentry><refentrytitle>glTexSubImage1D</refentrytitle></citerefentry>,
 225             <citerefentry><refentrytitle>glTexSubImage2D</refentrytitle></citerefentry>,
 226             <citerefentry><refentrytitle>glTexSubImage3D</refentrytitle></citerefentry>
 227         </para>
 228     </refsect1>
 229     <refsect1 id="Copyright"><title>Copyright</title>
 230         <para>
 231             Copyright <trademark class="copyright"></trademark> 1991-2006
 232             Silicon Graphics, Inc. This document is licensed under the SGI
 233             Free Software B License. For details, see
 234             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
 235         </para>
 236     </refsect1>
 237 </refentry>