upstream-man-pages/man4/xhtml/glDepthRangeIndexed.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
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   4 <?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" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glDepthRangeIndexed - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glDepthRangeIndexed"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDepthRangeIndexed — specify mapping of depth values from normalized device coordinates to window coordinates for a specified viewport</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">glDepthRangeIndexed</b>(</code></td><td>GLuint  </td><td><var class="pdparam">index</var>, </td></tr><tr><td> </td><td>GLdouble  </td><td><var class="pdparam">nearVal</var>, </td></tr><tr><td> </td><td>GLdouble  </td><td><var class="pdparam">farVal</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>index</code></em></span></dt><dd><p>
   5                     Specifies the index of the viewport whose depth range to update.
   6                 </p></dd><dt><span class="term"><em class="parameter"><code>nearVal</code></em></span></dt><dd><p>
   7                     Specifies the mapping of the near clipping plane to window coordinates.
   8                     The initial value is 0.
   9                 </p></dd><dt><span class="term"><em class="parameter"><code>farVal</code></em></span></dt><dd><p>
  10                     Specifies the mapping of the far clipping plane to window coordinates.
  11                     The initial value is 1.
  12                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  13             After clipping and division by <span class="emphasis"><em>w</em></span>,
  14             depth coordinates range from
  15             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  16
  17                 <mml:mn>-1</mml:mn>
  18             </mml:math>
  19             to 1,
  20             corresponding to the near and far clipping planes.
  21             Each viewport has an independent depth range specified as a linear mapping of the normalized
  22             depth coordinates in this range to window depth coordinates.
  23             Regardless of the actual depth buffer implementation,
  24             window coordinate depth values are treated as though they range
  25             from 0 through 1 (like color components).
  26             <code class="function">glDepthRangeIndexed</code> specifies a linear mapping of the normalized depth coordinates
  27             in this range to window depth coordinates for a specified viewport.
  28             Thus,
  29             the values accepted by <code class="function">glDepthRangeIndexed</code> are both clamped to this range
  30             before they are accepted.
  31         </p><p>
  32             The <em class="parameter"><code>index</code></em> parameter specifies the index of first viewport whose depth
  33             range to modify and must be less than the value of <code class="constant">GL_MAX_VIEWPORTS</code>.
  34             <em class="parameter"><code>nearVal</code></em> and <em class="parameter"><code>farVal</code></em> specify near and far values of the
  35             depth range for the specified viewport, respectively.
  36         </p><p>
  37             The setting of (0,1) maps the near plane to 0 and
  38             the far plane to 1.
  39             With this mapping,
  40             the depth buffer range is fully utilized.
  41         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  42             It is not necessary that the near plane distance be less than the far plane distance.
  43             Reverse mappings such as
  44             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  45
  46                 <mml:mrow>
  47                     <mml:mi mathvariant="italic">nearVal</mml:mi>
  48                     <mml:mo>=</mml:mo>
  49                     <mml:mn>1</mml:mn>
  50                 </mml:mrow>
  51             </mml:math>,
  52             and
  53             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  54
  55                 <mml:mrow>
  56                     <mml:mi mathvariant="italic">farVal</mml:mi>
  57                     <mml:mo>=</mml:mo>
  58                     <mml:mn>0</mml:mn>
  59                 </mml:mrow>
  60             </mml:math>
  61             are acceptable.
  62         </p><p>
  63             The type of the <em class="parameter"><code>nearVal</code></em> and
  64             <em class="parameter"><code>farVal</code></em> parameters was changed from
  65             GLclampd to GLdouble. This change is transparent to user
  66             code and is described in detail on the
  67             <a href="removedTypes.xml"><span class="citerefentry"><span class="refentrytitle">removedTypes</span></span></a>
  68             page.
  69         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  70             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>index</code></em> is greater than or equal to
  71             the value of <code class="constant">GL_MAX_VIEWPORTS</code>.
  72         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
  73             <a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_DEPTH_RANGE</code>
  74         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
  75             <a href="glDepthFunc.xml"><span class="citerefentry"><span class="refentrytitle">glDepthFunc</span></span></a>,
  76             <a href="glDepthRange.xml"><span class="citerefentry"><span class="refentrytitle">glDepthRange</span></span></a>,
  77             <a href="glDepthRangeArray.xml"><span class="citerefentry"><span class="refentrytitle">glDepthRangeArray</span></span></a>,
  78             <a href="glPolygonOffset.xml"><span class="citerefentry"><span class="refentrytitle">glPolygonOffset</span></span></a>,
  79             <a href="glViewportArray.xml"><span class="citerefentry"><span class="refentrytitle">glViewportArray</span></span></a>,
  80             <a href="glViewport.xml"><span class="citerefentry"><span class="refentrytitle">glViewport</span></span></a>,
  81             <a href="removedTypes.xml"><span class="citerefentry"><span class="refentrytitle">removedTypes</span></span></a>
  82         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  83             Copyright <span class="trademark"></span>© 2010 Khronos Group.
  84             This material may be distributed subject to the terms and conditions set forth in
  85             the Open Publication License, v 1.0, 8 June 1999.
  86             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
  87         </p></div></div></body></html>