upstream-doc/man2/glPrioritizeTextures.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="glPrioritizeTextures">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glPrioritizeTextures</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glPrioritizeTextures</refname>
  17         <refpurpose>set texture residence priority</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glPrioritizeTextures</function></funcdef>
  23                 <paramdef>GLsizei <parameter>n</parameter></paramdef>
  24                 <paramdef>const GLuint * <parameter>textures</parameter></paramdef>
  25                 <paramdef>const GLclampf * <parameter>priorities</parameter></paramdef>
  26             </funcprototype>
  27         </funcsynopsis>
  28     </refsynopsisdiv>
  29     <refsect1 id="parameters"><title>Parameters</title>
  30         <variablelist>
  31         <varlistentry>
  32             <term><parameter>n</parameter></term>
  33             <listitem>
  34                 <para>
  35                     Specifies the number of textures to be prioritized.
  36                 </para>
  37             </listitem>
  38         </varlistentry>
  39         <varlistentry>
  40             <term><parameter>textures</parameter></term>
  41             <listitem>
  42                 <para>
  43                     Specifies an array containing the names of the textures to be prioritized.
  44                 </para>
  45             </listitem>
  46         </varlistentry>
  47         <varlistentry>
  48             <term><parameter>priorities</parameter></term>
  49             <listitem>
  50                 <para>
  51                     Specifies an array containing the texture priorities.
  52                     A priority given in an element of <parameter>priorities</parameter> applies to the texture
  53                     named by the corresponding element of <parameter>textures</parameter>.
  54                 </para>
  55             </listitem>
  56         </varlistentry>
  57         </variablelist>
  58     </refsect1>
  59     <refsect1 id="description"><title>Description</title>
  60         <para>
  61             <function>glPrioritizeTextures</function> assigns the <parameter>n</parameter> texture priorities given in <parameter>priorities</parameter> to the
  62             <parameter>n</parameter> textures named in <parameter>textures</parameter>.
  63         </para>
  64         <para>
  65             The GL establishes
  66             a ``working set'' of textures that are resident in texture memory.
  67             These textures may be bound to a texture target much more efficiently
  68             than textures that are not resident.
  69             By specifying a priority for each texture,
  70             <function>glPrioritizeTextures</function> allows applications to guide the GL implementation in determining
  71             which textures should be resident.
  72         </para>
  73         <para>
  74             The priorities given in <parameter>priorities</parameter> are clamped to the range
  75             <inlineequation><mml:math>
  76                 <!-- eqn: [0,1]:-->
  77                 <mml:mfenced open="[" close="]">
  78                     <mml:mn>0</mml:mn>
  79                     <mml:mn>1</mml:mn>
  80                 </mml:mfenced>
  81             </mml:math></inlineequation>
  82             before they are assigned.
  83             0 indicates the lowest priority; textures with priority 0
  84             are least likely to be resident.
  85             1 indicates the highest priority; textures with priority 1
  86             are most likely to be resident.
  87             However, textures are not guaranteed to be resident until they are used.
  88         </para>
  89         <para>
  90             <function>glPrioritizeTextures</function> silently ignores attempts to prioritize texture 0 or any texture
  91             name that does not correspond to an existing texture.
  92         </para>
  93         <para>
  94             <function>glPrioritizeTextures</function> does not require that any of the textures named by <parameter>textures</parameter>
  95             be bound to a texture target.
  96             <citerefentry><refentrytitle>glTexParameter</refentrytitle></citerefentry> may also be used to set a texture's priority,
  97             but only if the texture is currently bound.
  98             This is the only way to set the priority of a default texture.
  99         </para>
 100     </refsect1>
 101     <refsect1 id="notes"><title>Notes</title>
 102         <para>
 103             <function>glPrioritizeTextures</function> is available only if the GL version is 1.1 or greater.
 104         </para>
 105     </refsect1>
 106     <refsect1 id="errors"><title>Errors</title>
 107         <para>
 108             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>n</parameter> is negative.
 109         </para>
 110         <para>
 111             <constant>GL_INVALID_OPERATION</constant> is generated if <function>glPrioritizeTextures</function> is executed
 112             between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry> and the corresponding
 113             execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
 114         </para>
 115     </refsect1>
 116     <refsect1 id="associatedgets"><title>Associated Gets</title>
 117         <para>
 118             <citerefentry><refentrytitle>glGetTexParameter</refentrytitle></citerefentry> with parameter name <constant>GL_TEXTURE_PRIORITY</constant>
 119             retrieves the priority of a currently bound texture.
 120         </para>
 121     </refsect1>
 122     <refsect1 id="seealso"><title>See Also</title>
 123         <para>
 124             <citerefentry><refentrytitle>glAreTexturesResident</refentrytitle></citerefentry>,
 125             <citerefentry><refentrytitle>glBindTexture</refentrytitle></citerefentry>,
 126             <citerefentry><refentrytitle>glCopyTexImage1D</refentrytitle></citerefentry>,
 127             <citerefentry><refentrytitle>glCopyTexImage2D</refentrytitle></citerefentry>,
 128             <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>,
 129             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
 130             <citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>,
 131             <citerefentry><refentrytitle>glTexParameter</refentrytitle></citerefentry>
 132         </para>
 133     </refsect1>
 134     <refsect1 id="Copyright"><title>Copyright</title>
 135         <para>
 136             Copyright <trademark class="copyright"></trademark> 1991-2006
 137             Silicon Graphics, Inc. This document is licensed under the SGI
 138             Free Software B License. For details, see
 139             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
 140         </para>
 141     </refsect1>
 142 </refentry>