upstream-man-pages/man3/glGenerateMipmap.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="glGenerateMipmap">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2010</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGenerateMipmap</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGenerateMipmap</refname>
  17         <refpurpose>generate mipmaps for a specified texture target</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGenerateMipmap</function></funcdef>
  23                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  24             </funcprototype>
  25         </funcsynopsis>
  26     </refsynopsisdiv>
  27     <!-- eqn: ignoring delim $$ -->
  28     <refsect1 id="parameters"><title>Parameters</title>
  29         <variablelist>
  30         <varlistentry>
  31             <term><parameter>target</parameter></term>
  32             <listitem>
  33                 <para>
  34                     Specifies the target to which the texture whose mimaps to generate is bound. <parameter>target</parameter> must
  35                     be <constant>GL_TEXTURE_1D</constant>, <constant>GL_TEXTURE_2D</constant>, <constant>GL_TEXTURE_3D</constant>,
  36                     <constant>GL_TEXTURE_1D_ARRAY</constant>, <constant>GL_TEXTURE_2D_ARRAY</constant> or
  37                     <constant>GL_TEXTURE_CUBE_MAP</constant>.
  38                 </para>
  39             </listitem>
  40         </varlistentry>
  41         </variablelist>
  42     </refsect1>
  43     <refsect1 id="description"><title>Description</title>
  44         <para>
  45             <function>glGenerateMipmap</function> generates mipmaps for the texture attached
  46             to <parameter>target</parameter> of the active texture unit. For cube map textures,
  47             a <constant>GL_INVALID_OPERATION</constant> error is generated if the texture
  48             attached to <parameter>target</parameter> is not cube complete.
  49         </para>
  50         <para>
  51             Mipmap generation replaces texel array levels
  52             <inlineequation><mml:math>
  53                 <!-- eqn: level sub base  +  1: -->
  54                 <mml:mrow>
  55                     <mml:msub>
  56                         <mml:mi mathvariant="italic">level</mml:mi>
  57                         <mml:mi>base</mml:mi>
  58                     </mml:msub>
  59                     <mml:mo>+</mml:mo>
  60                     <mml:mn>1</mml:mn>
  61                 </mml:mrow>
  62             </mml:math></inlineequation>
  63             through
  64             <inlineequation><mml:math>
  65                 <mml:mrow>
  66                     <mml:mi mathvariant="italic">q</mml:mi>
  67                 </mml:mrow>
  68             </mml:math></inlineequation>
  69             with arrays derived from the
  70             <inlineequation><mml:math>
  71                 <!-- eqn: level sub base  +  1: -->
  72                 <mml:mrow>
  73                     <mml:msub>
  74                         <mml:mi mathvariant="italic">level</mml:mi>
  75                         <mml:mi>base</mml:mi>
  76                     </mml:msub>
  77                 </mml:mrow>
  78             </mml:math></inlineequation>
  79             array, regardless of their previous contents. All other mimap arrays,
  80             including the
  81             <inlineequation><mml:math>
  82                 <!-- eqn: level sub base  +  1: -->
  83                 <mml:mrow>
  84                     <mml:msub>
  85                         <mml:mi mathvariant="italic">level</mml:mi>
  86                         <mml:mi>base</mml:mi>
  87                     </mml:msub>
  88                 </mml:mrow>
  89             </mml:math></inlineequation>
  90             array, are left unchanged by this computation.
  91         </para>
  92         <para>
  93             The internal formats of the derived mipmap arrays all match those of the
  94             <inlineequation><mml:math>
  95                 <!-- eqn: level sub base  +  1: -->
  96                 <mml:mrow>
  97                     <mml:msub>
  98                         <mml:mi mathvariant="italic">level</mml:mi>
  99                         <mml:mi>base</mml:mi>
 100                     </mml:msub>
 101                 </mml:mrow>
 102             </mml:math></inlineequation>
 103             array. The contents of the derived arrays are computed by repeated, filtered
 104             reduction of the
 105             <inlineequation><mml:math>
 106                 <!-- eqn: level sub base  +  1: -->
 107                 <mml:mrow>
 108                     <mml:msub>
 109                         <mml:mi mathvariant="italic">level</mml:mi>
 110                         <mml:mi>base</mml:mi>
 111                     </mml:msub>
 112                 </mml:mrow>
 113             </mml:math></inlineequation>
 114             array. For one- and two-dimensional texture arrays, each layer is filtered
 115             independently.
 116         </para>
 117     </refsect1>
 118     <refsect1 id="errors"><title>Errors</title>
 119         <para>
 120             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not
 121             one of the accepted texture targets.
 122         </para>
 123         <para>
 124             <constant>GL_INVALID_OPERATION</constant> is generated if <parameter>target</parameter> is
 125             <constant>GL_TEXTURE_CUBE_MAP</constant> and the texture bound to the <constant>GL_TEXTURE_CUBE_MAP</constant>
 126             target of the active texture unit is not cube complete.
 127         </para>
 128     </refsect1>
 129     <refsect1 id="seealso"><title>See Also</title>
 130         <para>
 131             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
 132             <citerefentry><refentrytitle>glBindTexture</refentrytitle></citerefentry>,
 133             <citerefentry><refentrytitle>glGenTextures</refentrytitle></citerefentry>
 134         </para>
 135     </refsect1>
 136     <refsect1 id="Copyright"><title>Copyright</title>
 137         <para>
 138             Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
 139             This material may be distributed subject to the terms and conditions set forth in
 140             the Open Publication License, v 1.0, 8 June 1999.
 141             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 142         </para>
 143     </refsect1>
 144 </refentry>