upstream-doc/man4/glClearColor.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="glClearColor">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glClearColor</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glClearColor</refname>
  17         <refpurpose>specify clear values for the color buffers</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glClearColor</function></funcdef>
  23                 <paramdef>GLfloat <parameter>red</parameter></paramdef>
  24                 <paramdef>GLfloat <parameter>green</parameter></paramdef>
  25                 <paramdef>GLfloat <parameter>blue</parameter></paramdef>
  26                 <paramdef>GLfloat <parameter>alpha</parameter></paramdef>
  27             </funcprototype>
  28         </funcsynopsis>
  29     </refsynopsisdiv>
  30     <refsect1 id="parameters"><title>Parameters</title>
  31         <variablelist>
  32         <varlistentry>
  33             <term><parameter>red</parameter></term>
  34             <term><parameter>green</parameter></term>
  35             <term><parameter>blue</parameter></term>
  36             <term><parameter>alpha</parameter></term>
  37             <listitem>
  38                 <para>
  39                     Specify the red, green, blue, and alpha values used when the
  40                     color buffers are cleared.
  41                     The initial values are all 0.
  42                 </para>
  43             </listitem>
  44         </varlistentry>
  45         </variablelist>
  46     </refsect1>
  47     <refsect1 id="description"><title>Description</title>
  48         <para>
  49             <function>glClearColor</function> specifies the red,
  50             green,
  51             blue,
  52             and alpha values used by <citerefentry><refentrytitle>glClear</refentrytitle></citerefentry> to clear the color buffers.
  53             Values specified by <function>glClearColor</function> are clamped to the range
  54             <inlineequation><mml:math>
  55                 <!-- eqn: [0,1]: -->
  56                 <mml:mfenced open="[" close="]">
  57                     <mml:mn>0</mml:mn>
  58                     <mml:mn>1</mml:mn>
  59                 </mml:mfenced>
  60             </mml:math></inlineequation>.
  61         </para>
  62     </refsect1>
  63     <refsect1 id="notes"><title>Notes</title>
  64         <para>
  65             The type of the <parameter>red</parameter>,
  66             <parameter>green</parameter>, <parameter>blue</parameter>,
  67             and <parameter>alpha</parameter> parameters was changed from
  68             GLclampf to GLfloat. This change is transparent to user code
  69             and is described in detail on the
  70             <citerefentry><refentrytitle>removedTypes</refentrytitle></citerefentry>
  71             page.
  72         </para>
  73     </refsect1>
  74     <refsect1 id="associatedgets"><title>Associated Gets</title>
  75         <para>
  76             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_COLOR_CLEAR_VALUE</constant>
  77         </para>
  78     </refsect1>
  79     <refsect1 id="seealso"><title>See Also</title>
  80         <para>
  81             <citerefentry><refentrytitle>glClear</refentrytitle></citerefentry>,
  82             <citerefentry><refentrytitle>removedTypes</refentrytitle></citerefentry>
  83         </para>
  84     </refsect1>
  85     <refsect1 id="Copyright"><title>Copyright</title>
  86         <para>
  87             Copyright <trademark class="copyright"></trademark> 1991-2006
  88             Silicon Graphics, Inc. This document is licensed under the SGI
  89             Free Software B License. For details, see
  90             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
  91         </para>
  92     </refsect1>
  93 </refentry>