upstream-doc/man2/xhtml/glGetPixelMap.xml

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   3 <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glGetPixelMap</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glGetPixelMap"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetPixelMap — return the specified pixel map</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">glGetPixelMapfv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">map</var>, </td></tr><tr><td> </td><td>GLfloat *  </td><td><var class="pdparam">data</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glGetPixelMapuiv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">map</var>, </td></tr><tr><td> </td><td>GLuint *  </td><td><var class="pdparam">data</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glGetPixelMapusv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">map</var>, </td></tr><tr><td> </td><td>GLushort *  </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>map</code></em></span></dt><dd><p>
   4                     Specifies the name of the pixel map to return.
   5                     Accepted values are
   6                     <code class="constant">GL_PIXEL_MAP_I_TO_I</code>,
   7                     <code class="constant">GL_PIXEL_MAP_S_TO_S</code>,
   8                     <code class="constant">GL_PIXEL_MAP_I_TO_R</code>,
   9                     <code class="constant">GL_PIXEL_MAP_I_TO_G</code>,
  10                     <code class="constant">GL_PIXEL_MAP_I_TO_B</code>,
  11                     <code class="constant">GL_PIXEL_MAP_I_TO_A</code>,
  12                     <code class="constant">GL_PIXEL_MAP_R_TO_R</code>,
  13                     <code class="constant">GL_PIXEL_MAP_G_TO_G</code>,
  14                     <code class="constant">GL_PIXEL_MAP_B_TO_B</code>, and
  15                     <code class="constant">GL_PIXEL_MAP_A_TO_A</code>.
  16                 </p></dd><dt><span class="term"><em class="parameter"><code>data</code></em></span></dt><dd><p>
  17                     Returns the pixel map contents.
  18                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  19             See the <a class="citerefentry" href="glPixelMap.xml"><span class="citerefentry"><span class="refentrytitle">glPixelMap</span></span></a> reference page for a description of the acceptable
  20             values for the <em class="parameter"><code>map</code></em> parameter.
  21             <code class="function">glGetPixelMap</code> returns in <em class="parameter"><code>data</code></em> the contents of the pixel map
  22             specified in <em class="parameter"><code>map</code></em>.
  23             Pixel maps are used during the execution of
  24             <a class="citerefentry" href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a>,
  25             <a class="citerefentry" href="glDrawPixels.xml"><span class="citerefentry"><span class="refentrytitle">glDrawPixels</span></span></a>,
  26             <a class="citerefentry" href="glCopyPixels.xml"><span class="citerefentry"><span class="refentrytitle">glCopyPixels</span></span></a>,
  27             <a class="citerefentry" href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
  28             <a class="citerefentry" href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
  29             <a class="citerefentry" href="glTexImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,
  30             <a class="citerefentry" href="glTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
  31             <a class="citerefentry" href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
  32             <a class="citerefentry" href="glTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</span></span></a>,
  33             <a class="citerefentry" href="glCopyTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
  34             <a class="citerefentry" href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,
  35             <a class="citerefentry" href="glCopyTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
  36             <a class="citerefentry" href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>, and
  37             <a class="citerefentry" href="glCopyTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>.
  38             to map color indices,
  39             stencil indices,
  40             color components,
  41             and depth components to other values.
  42         </p><p>
  43             If a non-zero named buffer object is bound to the <code class="constant">GL_PIXEL_PACK_BUFFER</code> target
  44             (see <a class="citerefentry" href="glBindBuffer.xml"><span class="citerefentry"><span class="refentrytitle">glBindBuffer</span></span></a>) while a pixel map is
  45             requested, <em class="parameter"><code>data</code></em> is treated as a byte offset into the buffer object's data store.
  46         </p><p>
  47             Unsigned integer values,
  48             if requested,
  49             are linearly mapped from the internal fixed or floating-point representation
  50             such that 1.0 maps to the largest representable integer value,
  51             and 0.0 maps to 0.
  52             Return unsigned integer values are undefined if the map value was
  53             not in the range [0,1].
  54         </p><p>
  55             To determine the required size of <em class="parameter"><code>map</code></em>,
  56             call <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with the appropriate symbolic
  57             constant.
  58         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  59             If an error is generated,
  60             no change is made to the contents of <em class="parameter"><code>data</code></em>.
  61         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  62             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>map</code></em> is not an accepted value.
  63         </p><p>
  64             <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to the
  65             <code class="constant">GL_PIXEL_PACK_BUFFER</code> target and the buffer object's data store is currently mapped.
  66         </p><p>
  67             <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to the
  68             <code class="constant">GL_PIXEL_PACK_BUFFER</code> target and the data would be packed to the buffer
  69             object such that the memory writes required would exceed the data store size.
  70         </p><p>
  71             <code class="constant">GL_INVALID_OPERATION</code> is generated by <code class="function">glGetPixelMapfv</code> if a non-zero buffer object name is bound to the
  72             <code class="constant">GL_PIXEL_PACK_BUFFER</code> target and <em class="parameter"><code>data</code></em> is not evenly divisible
  73             into the number of bytes needed to store in memory a GLfloat datum.
  74         </p><p>
  75             <code class="constant">GL_INVALID_OPERATION</code> is generated by <code class="function">glGetPixelMapuiv</code> if a non-zero buffer object name is bound to the
  76             <code class="constant">GL_PIXEL_PACK_BUFFER</code> target and <em class="parameter"><code>data</code></em> is not evenly divisible
  77             into the number of bytes needed to store in memory a GLuint datum.
  78         </p><p>
  79             <code class="constant">GL_INVALID_OPERATION</code> is generated by <code class="function">glGetPixelMapusv</code> if a non-zero buffer object name is bound to the
  80             <code class="constant">GL_PIXEL_PACK_BUFFER</code> target and <em class="parameter"><code>data</code></em> is not evenly divisible
  81             into the number of bytes needed to store in memory a GLushort datum.
  82         </p><p>
  83             <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glGetPixelMap</code>
  84             is executed between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
  85             and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
  86         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
  87             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_I_TO_I_SIZE</code>
  88         </p><p>
  89             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_S_TO_S_SIZE</code>
  90         </p><p>
  91             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_I_TO_R_SIZE</code>
  92         </p><p>
  93             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_I_TO_G_SIZE</code>
  94         </p><p>
  95             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_I_TO_B_SIZE</code>
  96         </p><p>
  97             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_I_TO_A_SIZE</code>
  98         </p><p>
  99             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_R_TO_R_SIZE</code>
 100         </p><p>
 101             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_G_TO_G_SIZE</code>
 102         </p><p>
 103             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_B_TO_B_SIZE</code>
 104         </p><p>
 105             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_MAP_A_TO_A_SIZE</code>
 106         </p><p>
 107             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_PIXEL_MAP_TABLE</code>
 108         </p><p>
 109             <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PIXEL_PACK_BUFFER_BINDING</code>
 110         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 111             <a class="citerefentry" href="glColorSubTable.xml"><span class="citerefentry"><span class="refentrytitle">glColorSubTable</span></span></a>,
 112             <a class="citerefentry" href="glColorTable.xml"><span class="citerefentry"><span class="refentrytitle">glColorTable</span></span></a>,
 113             <a class="citerefentry" href="glConvolutionFilter1D.xml"><span class="citerefentry"><span class="refentrytitle">glConvolutionFilter1D</span></span></a>,
 114             <a class="citerefentry" href="glConvolutionFilter2D.xml"><span class="citerefentry"><span class="refentrytitle">glConvolutionFilter2D</span></span></a>,
 115             <a class="citerefentry" href="glCopyColorSubTable.xml"><span class="citerefentry"><span class="refentrytitle">glCopyColorSubTable</span></span></a>,
 116             <a class="citerefentry" href="glCopyColorTable.xml"><span class="citerefentry"><span class="refentrytitle">glCopyColorTable</span></span></a>,
 117             <a class="citerefentry" href="glCopyPixels.xml"><span class="citerefentry"><span class="refentrytitle">glCopyPixels</span></span></a>,
 118             <a class="citerefentry" href="glCopyTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage1D</span></span></a>,
 119             <a class="citerefentry" href="glCopyTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,
 120             <a class="citerefentry" href="glCopyTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage1D</span></span></a>,
 121             <a class="citerefentry" href="glCopyTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,
 122             <a class="citerefentry" href="glCopyTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>,
 123             <a class="citerefentry" href="glDrawPixels.xml"><span class="citerefentry"><span class="refentrytitle">glDrawPixels</span></span></a>,
 124             <a class="citerefentry" href="glGetHistogram.xml"><span class="citerefentry"><span class="refentrytitle">glGetHistogram</span></span></a>,
 125             <a class="citerefentry" href="glGetMinmax.xml"><span class="citerefentry"><span class="refentrytitle">glGetMinmax</span></span></a>,
 126             <a class="citerefentry" href="glGetTexImage.xml"><span class="citerefentry"><span class="refentrytitle">glGetTexImage</span></span></a>,
 127             <a class="citerefentry" href="glPixelMap.xml"><span class="citerefentry"><span class="refentrytitle">glPixelMap</span></span></a>,
 128             <a class="citerefentry" href="glPixelTransfer.xml"><span class="citerefentry"><span class="refentrytitle">glPixelTransfer</span></span></a>,
 129             <a class="citerefentry" href="glReadPixels.xml"><span class="citerefentry"><span class="refentrytitle">glReadPixels</span></span></a>,
 130             <a class="citerefentry" href="glSeparableFilter2D.xml"><span class="citerefentry"><span class="refentrytitle">glSeparableFilter2D</span></span></a>,
 131             <a class="citerefentry" href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
 132             <a class="citerefentry" href="glTexImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage1D</span></span></a>,
 133             <a class="citerefentry" href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>
 134             <a class="citerefentry" href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
 135             <a class="citerefentry" href="glTexImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,
 136             <a class="citerefentry" href="glTexSubImage1D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage1D</span></span></a>,
 137             <a class="citerefentry" href="glTexSubImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,
 138             <a class="citerefentry" href="glTexSubImage3D.xml"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</span></span></a>
 139         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 140             Copyright <span class="trademark"></span>© 1991-2006
 141             Silicon Graphics, Inc. This document is licensed under the SGI
 142             Free Software B License. For details, see
 143             <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
 144         </p></div></div></body></html>