upstream-doc/man4/glGetSubroutineUniformLocation.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="glGetSubroutineUniformLocation">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2010</year>
   9                 <holder>Khronos Group.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetSubroutineUniformLocation</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetSubroutineUniformLocation</refname>
  17         <refpurpose>retrieve the location of a subroutine uniform of a given shader stage within a program</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>GLint <function>glGetSubroutineUniformLocation</function></funcdef>
  23                 <paramdef>GLuint <parameter>program</parameter></paramdef>
  24                 <paramdef>GLenum <parameter>shadertype</parameter></paramdef>
  25                 <paramdef>const GLchar *<parameter>name</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>program</parameter></term>
  34             <listitem>
  35                 <para>
  36                     Specifies the name of the program containing shader stage.
  37                 </para>
  38             </listitem>
  39         </varlistentry>
  40         <varlistentry>
  41             <term><parameter>shadertype</parameter></term>
  42             <listitem>
  43                 <para>
  44                     Specifies the shader stage from which to query for subroutine uniform index.
  45                     <parameter>shadertype</parameter>
  46                     must be one of <constant>GL_VERTEX_SHADER</constant>, <constant>GL_TESS_CONTROL_SHADER</constant>,
  47                     <constant>GL_TESS_EVALUATION_SHADER</constant>, <constant>GL_GEOMETRY_SHADER</constant> or
  48                     <constant>GL_FRAGMENT_SHADER</constant>.
  49                 </para>
  50             </listitem>
  51         </varlistentry>
  52         <varlistentry>
  53             <term><parameter>name</parameter></term>
  54             <listitem>
  55                 <para>
  56                     Specifies the name of the subroutine uniform whose index to query.
  57                 </para>
  58             </listitem>
  59         </varlistentry>
  60         </variablelist>
  61     </refsect1>
  62     <refsect1 id="description"><title>Description</title>
  63         <para>
  64             <function>glGetSubroutineUniformLocation</function> returns the location of the subroutine uniform variable
  65             <parameter>name</parameter> in the shader stage of type <parameter>shadertype</parameter> attached to
  66             <parameter>program</parameter>, with behavior otherwise identical to
  67             <citerefentry><refentrytitle>glGetUniformLocation</refentrytitle></citerefentry>.
  68         </para>
  69         <para>
  70             If <parameter>name</parameter> is not the name of a subroutine uniform in the shader stage, -1
  71             is returned, but no error is generated. If <parameter>name</parameter> is the name of a subroutine uniform in the shader stage,
  72             a value between zero and the value of <constant>GL_ACTIVE_SUBROUTINE_LOCATIONS</constant> minus one will be returned.
  73             Subroutine locations are assigned using consecutive integers in the range from zero to the value
  74             of <constant>GL_ACTIVE_SUBROUTINE_LOCATIONS</constant> minus one for the shader stage.  For active subroutine uniforms
  75             declared as arrays, the declared array elements are assigned consecutive locations.
  76         </para>
  77     </refsect1>
  78     <refsect1 id="errors"><title>Errors</title>
  79         <para>
  80             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>shadertype</parameter> or <parameter>pname</parameter>
  81             is not one of the accepted values.
  82         </para>
  83         <para>
  84             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>program</parameter> is not the name of an
  85             existing program object.
  86         </para>
  87     </refsect1>
  88     <refsect1 id="seealso"><title>See Also</title>
  89         <para>
  90             <citerefentry><refentrytitle>glGetProgram</refentrytitle></citerefentry>,
  91             <citerefentry><refentrytitle>glGetActiveSubroutineUniform</refentrytitle></citerefentry>,
  92             <citerefentry><refentrytitle>glGetActiveSubroutineUniformName</refentrytitle></citerefentry>,
  93             <citerefentry><refentrytitle>glGetUniformLocation</refentrytitle></citerefentry>
  94         </para>
  95     </refsect1>
  96     <refsect1 id="Copyright"><title>Copyright</title>
  97         <para>
  98             Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
  99             This material may be distributed subject to the terms and conditions set forth in
 100             the Open Publication License, v 1.0, 8 June 1999.
 101             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 102         </para>
 103     </refsect1>
 104 </refentry>