upstream-doc/man4/glGetActiveAtomicCounterBufferiv.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="glGetActiveAtomicCounterBufferiv">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetActiveAtomicCounterBufferiv</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetActiveAtomicCounterBufferiv</refname>
  17         <refpurpose>retrieve information about the set of active atomic counter buffers for a program</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetActiveAtomicCounterBufferiv</function></funcdef>
  23                 <paramdef>Gluint <parameter>program</parameter></paramdef>
  24                 <paramdef>GLuint <parameter>bufferIndex</parameter></paramdef>
  25                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  26                 <paramdef>GLint *<parameter>params</parameter></paramdef>
  27             </funcprototype>
  28         </funcsynopsis>
  29     </refsynopsisdiv>
  30     <!-- eqn: ignoring delim $$ -->
  31     <refsect1 id="parameters"><title>Parameters</title>
  32         <variablelist>
  33         <varlistentry>
  34             <term><parameter>program</parameter></term>
  35             <listitem>
  36                 <para>
  37                     The name of a program object from which to retrieve information.
  38                 </para>
  39             </listitem>
  40         </varlistentry>
  41         <varlistentry>
  42             <term><parameter>bufferIndex</parameter></term>
  43             <listitem>
  44                 <para>
  45                     Specifies index of an active atomic counter buffer.
  46                 </para>
  47             </listitem>
  48         </varlistentry>
  49         <varlistentry>
  50             <term><parameter>pname</parameter></term>
  51             <listitem>
  52                 <para>
  53                     Specifies which parameter of the atomic counter buffer to retrieve.
  54                 </para>
  55             </listitem>
  56         </varlistentry>
  57         <varlistentry>
  58             <term><parameter>params</parameter></term>
  59             <listitem>
  60                 <para>
  61                     Specifies the address of a variable into which to write the retrieved information.
  62                 </para>
  63             </listitem>
  64         </varlistentry>
  65         </variablelist>
  66     </refsect1>
  67     <refsect1 id="description"><title>Description</title>
  68         <para>
  69             <function>glGetActiveAtomicCounterBufferiv</function> retrieves information about the set of active
  70             atomic counter buffers for a program object. <parameter>program</parameter> is the name of a program
  71             object for which the command <citerefentry><refentrytitle>glLinkProgram</refentrytitle></citerefentry>
  72             has been issued in the past. It is not necessary for <parameter>program</parameter> to have been linked
  73             successfully. The link may have failed because the number of active atomic counters exceeded the limits.
  74         </para>
  75         <para>
  76             <parameter>bufferIndex</parameter> specifies the index of an active atomic counter buffer and must be in
  77             the range zero to the value of <constant>GL_ACTIVE_ATOMIC_COUNTER_BUFFERS</constant> minus one. The value
  78             of <constant>GL_ACTIVE_ATOMIC_COUNTER_BUFFERS</constant> for <parameter>program</parameter> indicates the
  79             number of active atomic counter buffer and can be queried with
  80             <citerefentry><refentrytitle>glGetProgram</refentrytitle></citerefentry>.
  81         </para>
  82         <para>
  83             If no error occurs, the parameter(s) specified by <parameter>pname</parameter> are returned in <parameter>params</parameter>.
  84             If an error is generated, the contents of <parameter>params</parameter> are not modified.
  85         </para>
  86         <para>
  87             If <parameter>pname</parameter> is <constant>GL_ATOMIC_COUNTER_BUFFER_BINDING</constant>, then the index of the
  88             counter buffer binding point associated with the active atomic counter buffer <parameter>bufferIndex</parameter>
  89             for <parameter>program</parameter> is returned.
  90         </para>
  91         <para>
  92             If <parameter>pname</parameter> is <constant>GL_ATOMIC_COUNTER_BUFFER_DATA_SIZE</constant>, then the implementation-dependent
  93             minimum total buffer object size, in baseic machine units, required to hold all active atomic counters in the
  94             atomic counter binding point identified by <parameter>bufferIndex</parameter> is returned.
  95         </para>
  96         <para>
  97             If <parameter>pname</parameter> is <constant>GL_ATOMIC_COUNTER_BUFFER_ACTIVE_ATOMIC_COUNTERS</constant>, then the number of active
  98             atomic counters for the atomic counter buffer identified by <parameter>bufferIndex</parameter> is returned.
  99         </para>
 100         <para>
 101             If <parameter>pname</parameter> is <constant>GL_ATOMIC_COUNTER_BUFFER_ACTIVE_ATOMIC_COUNTER_INDICES</constant>,
 102             then a list of the active atomic counter indices for the atomic counter buffer identified by <parameter>bufferIndex</parameter>
 103             is returned. The number of elements that will be written into <parameter>params</parameter> is the value of
 104             <constant>GL_ATOMIC_COUNTER_BUFFER_ACTIVE_ATOMIC_COUNTERS</constant> for <parameter>bufferIndex</parameter>.
 105         </para>
 106         <para>
 107             If <parameter>pname</parameter> is <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_VERTEX_SHADER</constant>,
 108             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_TESS_CONTROL_SHADER</constant>,
 109             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_TESS_EVALUATION_SHADER</constant>,
 110             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_GEOMETRY_SHADER</constant>,
 111             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_FRAGMENT_SHADER</constant>,
 112             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_COMPUTE_SHADER</constant> then a boolean value indicating
 113             whether the atomic counter buffer identified by <parameter>bufferIndex</parameter> is referenced by the vertex,
 114             tessellation control, tessellation evaluation, geometry, fragment or compute processing stages of <parameter>program</parameter>,
 115             respectively, is returned.
 116         </para>
 117     </refsect1>
 118     <refsect1 id="notes"><title>Notes</title>
 119         <para>
 120             <function>glGetActiveAtomicCounterBufferiv</function> is available only if the
 121             GL version is 4.2 or higher.
 122         </para>
 123         <para>
 124             <constant>GL_ATOMIC_COUNTER_BUFFER_REFERENCED_BY_COMPUTE_SHADER</constant> is available
 125             only of the GL version is 4.3 or higher.
 126         </para>
 127     </refsect1>
 128     <refsect1 id="errors"><title>Errors</title>
 129         <para>
 130             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>program</parameter> is not the name of a program
 131             object for which <citerefentry><refentrytitle>glLinkProgram</refentrytitle></citerefentry> has been called in the past.
 132         </para>
 133         <para>
 134             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>bufferIndex</parameter> is greater than or equal to
 135             the value of <constant>GL_ACTIVE_ATOMIC_COUNTER_BUFFERS</constant> for <parameter>program</parameter>.
 136         </para>
 137         <para>
 138             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not one of the accepted tokens.
 139         </para>
 140     </refsect1>
 141     <refsect1 id="seealso"><title>See Also</title>
 142         <para>
 143             <citerefentry><refentrytitle>glGetProgram</refentrytitle></citerefentry>,
 144             <citerefentry><refentrytitle>glGetActiveSubroutineUniform</refentrytitle></citerefentry>,
 145             <citerefentry><refentrytitle>glGetActiveSubroutineUniformName</refentrytitle></citerefentry>,
 146             <citerefentry><refentrytitle>glGetUniformLocation</refentrytitle></citerefentry>
 147         </para>
 148     </refsect1>
 149     <refsect1 id="Copyright"><title>Copyright</title>
 150         <para>
 151             Copyright <trademark class="copyright"></trademark> 2011 Khronos Group.
 152             This material may be distributed subject to the terms and conditions set forth in
 153             the Open Publication License, v 1.0, 8 June 1999.
 154             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 155         </para>
 156     </refsect1>
 157 </refentry>