upstream-doc/man4/xhtml/glGenerateMipmap.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
   3 <!-- saved from url=(0013)about:internet -->
   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>glGenerateMipmap - 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="glGenerateMipmap"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGenerateMipmap — generate mipmaps for a specified texture target</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><p><code class="funcdef">void <b class="fsfunc">glGenerateMipmap</b>(</code>GLenum <var class="pdparam">target</var><code>)</code>;</p></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>
   5                     Specifies the target to which the texture whose mimaps to generate is bound. <em class="parameter"><code>target</code></em> must
   6                     be <code class="constant">GL_TEXTURE_1D</code>, <code class="constant">GL_TEXTURE_2D</code>, <code class="constant">GL_TEXTURE_3D</code>,
   7                     <code class="constant">GL_TEXTURE_1D_ARRAY</code>, <code class="constant">GL_TEXTURE_2D_ARRAY</code> or
   8                     <code class="constant">GL_TEXTURE_CUBE_MAP</code>.
   9                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  10             <code class="function">glGenerateMipmap</code> generates mipmaps for the texture attached
  11             to <em class="parameter"><code>target</code></em> of the active texture unit. For cube map textures,
  12             a <code class="constant">GL_INVALID_OPERATION</code> error is generated if the texture
  13             attached to <em class="parameter"><code>target</code></em> is not cube complete.
  14         </p><p>
  15             Mipmap generation replaces texel array levels
  16             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  17
  18                 <mml:mrow>
  19                     <mml:msub>
  20                         <mml:mi mathvariant="italic">level</mml:mi>
  21                         <mml:mi>base</mml:mi>
  22                     </mml:msub>
  23                     <mml:mo>+</mml:mo>
  24                     <mml:mn>1</mml:mn>
  25                 </mml:mrow>
  26             </mml:math>
  27             through
  28             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  29                 <mml:mrow>
  30                     <mml:mi mathvariant="italic">q</mml:mi>
  31                 </mml:mrow>
  32             </mml:math>
  33             with arrays derived from the
  34             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  35
  36                 <mml:mrow>
  37                     <mml:msub>
  38                         <mml:mi mathvariant="italic">level</mml:mi>
  39                         <mml:mi>base</mml:mi>
  40                     </mml:msub>
  41                 </mml:mrow>
  42             </mml:math>
  43             array, regardless of their previous contents. All other mimap arrays,
  44             including the
  45             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  46
  47                 <mml:mrow>
  48                     <mml:msub>
  49                         <mml:mi mathvariant="italic">level</mml:mi>
  50                         <mml:mi>base</mml:mi>
  51                     </mml:msub>
  52                 </mml:mrow>
  53             </mml:math>
  54             array, are left unchanged by this computation.
  55         </p><p>
  56             The internal formats of the derived mipmap arrays all match those of the
  57             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  58
  59                 <mml:mrow>
  60                     <mml:msub>
  61                         <mml:mi mathvariant="italic">level</mml:mi>
  62                         <mml:mi>base</mml:mi>
  63                     </mml:msub>
  64                 </mml:mrow>
  65             </mml:math>
  66             array. The contents of the derived arrays are computed by repeated, filtered
  67             reduction of the
  68             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  69
  70                 <mml:mrow>
  71                     <mml:msub>
  72                         <mml:mi mathvariant="italic">level</mml:mi>
  73                         <mml:mi>base</mml:mi>
  74                     </mml:msub>
  75                 </mml:mrow>
  76             </mml:math>
  77             array. For one- and two-dimensional texture arrays, each layer is filtered
  78             independently.
  79         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  80             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>target</code></em> is not
  81             one of the accepted texture targets.
  82         </p><p>
  83             <code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>target</code></em> is
  84             <code class="constant">GL_TEXTURE_CUBE_MAP</code> and the texture bound to the <code class="constant">GL_TEXTURE_CUBE_MAP</code>
  85             target of the active texture unit is not cube complete.
  86         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
  87             <a href="glTexImage2D.xml"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,
  88             <a href="glBindTexture.xml"><span class="citerefentry"><span class="refentrytitle">glBindTexture</span></span></a>,
  89             <a href="glGenTextures.xml"><span class="citerefentry"><span class="refentrytitle">glGenTextures</span></span></a>
  90         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  91             Copyright <span class="trademark"></span>© 2010 Khronos Group.
  92             This material may be distributed subject to the terms and conditions set forth in
  93             the Open Publication License, v 1.0, 8 June 1999.
  94             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
  95         </p></div></div></body></html>