upstream-doc/man3/glGetBufferParameter.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="glGetBufferParameter">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2005</year>
   9                 <holder>Sams Publishing</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetBufferParameteriv</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetBufferParameteriv</refname>
  17         <refpurpose>return parameters of a buffer object</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetBufferParameteriv</function></funcdef>
  23                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  24                 <paramdef>GLenum <parameter>value</parameter></paramdef>
  25                 <paramdef>GLint * <parameter>data</parameter></paramdef>
  26             </funcprototype>
  27         </funcsynopsis>
  28         <funcsynopsis>
  29             <funcprototype>
  30                 <funcdef>void <function>glGetBufferParameteri64v</function></funcdef>
  31                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  32                 <paramdef>GLenum <parameter>value</parameter></paramdef>
  33                 <paramdef>GLint64 * <parameter>data</parameter></paramdef>
  34             </funcprototype>
  35         </funcsynopsis>
  36     </refsynopsisdiv>
  37     <refsect1 id="parameters"><title>Parameters</title>
  38         <variablelist>
  39         <varlistentry>
  40             <term><parameter>target</parameter></term>
  41             <listitem>
  42                 <para>
  43                     Specifies the target buffer object.
  44                     The symbolic constant must be <constant>GL_ARRAY_BUFFER</constant>,
  45                     <constant>GL_COPY_READ_BUFFER</constant>,
  46                     <constant>GL_COPY_WRITE_BUFFER</constant>,
  47                     <constant>GL_ELEMENT_ARRAY_BUFFER</constant>,
  48                     <constant>GL_PIXEL_PACK_BUFFER</constant>,
  49                     <constant>GL_PIXEL_UNPACK_BUFFER</constant>,
  50                     <constant>GL_TEXTURE_BUFFER</constant>,
  51                     <constant>GL_TRANSFORM_FEEDBACK_BUFFER</constant>, or
  52                     <constant>GL_UNIFORM_BUFFER</constant>.
  53                 </para>
  54             </listitem>
  55         </varlistentry>
  56         <varlistentry>
  57             <term><parameter>value</parameter></term>
  58             <listitem>
  59                 <para>
  60                     Specifies the symbolic name of a buffer object parameter.
  61                     Accepted values are <constant>GL_BUFFER_ACCESS</constant>, <constant>GL_BUFFER_MAPPED</constant>,
  62                     <constant>GL_BUFFER_SIZE</constant>, or <constant>GL_BUFFER_USAGE</constant>.
  63                 </para>
  64             </listitem>
  65         </varlistentry>
  66         <varlistentry>
  67             <term><parameter>data</parameter></term>
  68             <listitem>
  69                 <para>
  70                     Returns the requested parameter.
  71                 </para>
  72             </listitem>
  73         </varlistentry>
  74         </variablelist>
  75     </refsect1>
  76     <refsect1 id="description"><title>Description</title>
  77         <para>
  78             <function>glGetBufferParameteriv</function> returns in <parameter>data</parameter> a selected parameter of the buffer object
  79             specified by <parameter>target</parameter>.
  80         </para>
  81         <para>
  82             <parameter>value</parameter> names a specific buffer object parameter, as follows:
  83         </para>
  84         <variablelist>
  85             <varlistentry>
  86                 <term><constant>GL_BUFFER_ACCESS</constant></term>
  87                 <listitem>
  88                     <para>
  89                         <parameter>params</parameter> returns the access policy set while mapping the buffer object.
  90                         The initial value is <constant>GL_READ_WRITE</constant>.
  91                     </para>
  92                 </listitem>
  93             </varlistentry>
  94             <varlistentry>
  95                 <term><constant>GL_BUFFER_MAPPED</constant></term>
  96                 <listitem>
  97                     <para>
  98                         <parameter>params</parameter> returns a flag indicating whether the buffer object is currently
  99                         mapped. The initial value is <constant>GL_FALSE</constant>.
 100                     </para>
 101                 </listitem>
 102             </varlistentry>
 103             <varlistentry>
 104                 <term><constant>GL_BUFFER_SIZE</constant></term>
 105                 <listitem>
 106                     <para>
 107                         <parameter>params</parameter> returns the size of the buffer object, measured in bytes.
 108                         The initial value is 0.
 109                     </para>
 110                 </listitem>
 111             </varlistentry>
 112             <varlistentry>
 113                 <term><constant>GL_BUFFER_USAGE</constant></term>
 114                 <listitem>
 115                     <para>
 116                         <parameter>params</parameter> returns the buffer object's usage pattern.  The initial value is
 117                         <constant>GL_STATIC_DRAW</constant>.
 118                     </para>
 119                 </listitem>
 120             </varlistentry>
 121         </variablelist>
 122     </refsect1>
 123     <refsect1 id="notes"><title>Notes</title>
 124         <para>
 125             If an error is generated,
 126             no change is made to the contents of <parameter>data</parameter>.
 127         </para>
 128         <para>
 129             <function>glGetBufferParameteri64v</function> is available only if the GL version is 3.2 or higher.
 130         </para>
 131     </refsect1>
 132     <refsect1 id="errors"><title>Errors</title>
 133         <para>
 134             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> or <parameter>value</parameter> is not an
 135             accepted value.
 136         </para>
 137         <para>
 138             <constant>GL_INVALID_OPERATION</constant> is generated if the reserved buffer object name 0 is bound to <parameter>target</parameter>.
 139         </para>
 140     </refsect1>
 141     <refsect1 id="seealso"><title>See Also</title>
 142         <para>
 143             <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>,
 144             <citerefentry><refentrytitle>glBufferData</refentrytitle></citerefentry>,
 145             <citerefentry><refentrytitle>glMapBuffer</refentrytitle></citerefentry>,
 146             <citerefentry><refentrytitle>glUnmapBuffer</refentrytitle></citerefentry>
 147         </para>
 148     </refsect1>
 149     <refsect1 id="Copyright"><title>Copyright</title>
 150         <para>
 151             Copyright <trademark class="copyright"></trademark> 2005 Addison-Wesley.
 152             Copyright <trademark class="copyright"></trademark> 2010-2013 Khronos Group.
 153             This material may be distributed subject to the terms and conditions set forth in
 154             the Open Publication License, v 1.0, 8 June 1999.
 155             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 156         </para>
 157     </refsect1>
 158 </refentry>