upstream-man-pages/man3/glGetMultisample.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="glGetMultisample">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2010</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetMultisamplefv</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetMultisamplefv</refname>
  17         <refpurpose>retrieve the location of a sample</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetMultisamplefv</function></funcdef>
  23                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  24                 <paramdef>GLuint <parameter>index</parameter></paramdef>
  25                 <paramdef>GLfloat *<parameter>val</parameter></paramdef>
  26             </funcprototype>
  27         </funcsynopsis>
  28     </refsynopsisdiv>
  29     <!-- eqn: ignoring delim $$ -->
  30     <refsect1 id="parameters"><title>Parameters</title>
  31         <variablelist>
  32         <varlistentry>
  33             <term><parameter>pname</parameter></term>
  34             <listitem>
  35                 <para>
  36                     Specifies the sample parameter name. <parameter>pname</parameter> must be <constant>GL_SAMPLE_POSITION</constant>.
  37                 </para>
  38             </listitem>
  39         </varlistentry>
  40         <varlistentry>
  41             <term><parameter>index</parameter></term>
  42             <listitem>
  43                 <para>
  44                     Specifies the index of the sample whose position to query.
  45                 </para>
  46             </listitem>
  47         </varlistentry>
  48         <varlistentry>
  49             <term><parameter>val</parameter></term>
  50             <listitem>
  51                 <para>
  52                     Specifies the address of an array to receive the position of the sample.
  53                 </para>
  54             </listitem>
  55         </varlistentry>
  56         </variablelist>
  57     </refsect1>
  58     <refsect1 id="description"><title>Description</title>
  59         <para>
  60             <function>glGetMultisamplefv</function> queries the location of a given sample. <parameter>pname</parameter>
  61             specifies the sample parameter to retrieve and must be <constant>GL_SAMPLE_POSITION</constant>. <parameter>index</parameter>
  62             corresponds to the sample for which the location should be returned. The sample location is returned as two floating-point
  63             values in <parameter>val[0]</parameter> and <parameter>val[1]</parameter>, each between 0 and 1, corresponding to the <parameter>x</parameter>
  64             and <parameter>y</parameter> locations respectively in the GL pixel space of that sample. (0.5, 0.5) this corresponds to the
  65             pixel center. <parameter>index</parameter> must be between zero and the value of <constant>GL_SAMPLES</constant> - 1.
  66         </para>
  67         <para>
  68             If the multisample mode does not have fixed sample locations, the returned values may only reflect the locations of samples
  69             within some pixels.
  70         </para>
  71     </refsect1>
  72     <refsect1 id="errors"><title>Errors</title>
  73         <para>
  74             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not one <constant>GL_SAMPLE_POSITION</constant>.
  75         </para>
  76         <para>
  77             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>index</parameter> is greater than or equal to the value of
  78             <constant>GL_SAMPLES</constant>.
  79         </para>
  80     </refsect1>
  81     <refsect1 id="seealso"><title>See Also</title>
  82         <para>
  83             <citerefentry><refentrytitle>glGenFramebuffers</refentrytitle></citerefentry>,
  84             <citerefentry><refentrytitle>glBindFramebuffer</refentrytitle></citerefentry>
  85         </para>
  86     </refsect1>
  87     <refsect1 id="Copyright"><title>Copyright</title>
  88         <para>
  89             Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
  90             This material may be distributed subject to the terms and conditions set forth in
  91             the Open Publication License, v 1.0, 8 June 1999.
  92             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
  93         </para>
  94     </refsect1>
  95 </refentry>