upstream-man-pages/man4/glDrawElementsBaseVertex.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="glDrawElementsBaseVertex">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2010</year>
   9                 <holder>Khronos Group</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glDrawElementsBaseVertex</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glDrawElementsBaseVertex</refname>
  17         <refpurpose>render primitives from array data with a per-element offset</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glDrawElementsBaseVertex</function></funcdef>
  23                 <paramdef>GLenum <parameter>mode</parameter></paramdef>
  24                 <paramdef>GLsizei <parameter>count</parameter></paramdef>
  25                 <paramdef>GLenum <parameter>type</parameter></paramdef>
  26                 <paramdef>GLvoid *<parameter>indices</parameter></paramdef>
  27                 <paramdef>GLint <parameter>basevertex</parameter></paramdef>
  28             </funcprototype>
  29         </funcsynopsis>
  30     </refsynopsisdiv>
  31     <!-- eqn: ignoring delim $$ -->
  32     <refsect1 id="parameters"><title>Parameters</title>
  33         <variablelist>
  34         <varlistentry>
  35             <term><parameter>mode</parameter></term>
  36             <listitem>
  37                 <para>
  38                     Specifies what kind of primitives to render.
  39                     Symbolic constants
  40                     <constant>GL_POINTS</constant>, <constant>GL_LINE_STRIP</constant>, <constant>GL_LINE_LOOP</constant>,
  41                     <constant>GL_LINES</constant>, <constant>GL_TRIANGLE_STRIP</constant>, <constant>GL_TRIANGLE_FAN</constant>,
  42                     <constant>GL_TRIANGLES</constant>, <constant>GL_LINES_ADJACENCY</constant>, <constant>GL_LINE_STRIP_ADJACENCY</constant>,
  43                     <constant>GL_TRIANGLES_ADJACENCY</constant>, <constant>GL_TRIANGLE_STRIP_ADJACENCY</constant> and <constant>GL_PATCHES</constant> are accepted.
  44                 </para>
  45             </listitem>
  46         </varlistentry>
  47         <varlistentry>
  48             <term><parameter>count</parameter></term>
  49             <listitem>
  50                 <para>
  51                     Specifies the number of elements to be rendered.
  52                 </para>
  53             </listitem>
  54         </varlistentry>
  55         <varlistentry>
  56             <term><parameter>type</parameter></term>
  57             <listitem>
  58                 <para>
  59                     Specifies the type of the values in indices. Must be one of <constant>GL_UNSIGNED_BYTE</constant>,
  60                     <constant>GL_UNSIGNED_SHORT</constant>, or <constant>GL_UNSIGNED_INT</constant>.
  61                 </para>
  62             </listitem>
  63         </varlistentry>
  64         <varlistentry>
  65             <term><parameter>indices</parameter></term>
  66             <listitem>
  67                 <para>
  68                     Specifies a pointer to the location where the indices are stored.
  69                 </para>
  70             </listitem>
  71         </varlistentry>
  72         <varlistentry>
  73             <term><parameter>basevertex</parameter></term>
  74             <listitem>
  75                 <para>
  76                     Specifies a constant that should be added to each element of <parameter>indices</parameter>
  77                     when chosing elements from the enabled vertex arrays.
  78                 </para>
  79             </listitem>
  80         </varlistentry>
  81         </variablelist>
  82     </refsect1>
  83     <refsect1 id="description"><title>Description</title>
  84         <para>
  85             <function>glDrawElementsBaseVertex</function> behaves identically to
  86             <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry> except that the <emphasis>i</emphasis>th element
  87             transferred by the corresponding draw call will be taken from element <parameter>indices</parameter>[i] + <parameter>basevertex</parameter>
  88             of each enabled array. If the resulting value is larger than the maximum value representable by <parameter>type</parameter>,
  89             it is as if the calculation were upconverted to 32-bit unsigned integers (with wrapping on overflow conditions).
  90             The operation is undefined if the sum would be negative.
  91         </para>
  92     </refsect1>
  93     <refsect1 id="notes"><title>Notes</title>
  94         <function>glDrawElementsBaseVertex</function> is only supported if the GL version is 3.2 or greater, or if
  95             the <code>ARB_draw_elements_base_vertex</code> extension is supported.
  96     </refsect1>
  97     <refsect1 id="errors"><title>Errors</title>
  98         <para>
  99             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>mode</parameter> is not an accepted value.
 100         </para>
 101         <para>
 102             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>count</parameter> is negative.
 103         </para>
 104         <para>
 105             <constant>GL_INVALID_OPERATION</constant> is generated if a geometry shader is active and <parameter>mode</parameter>
 106             is incompatible with the input primitive type of the geometry shader in the currently installed program object.
 107         </para>
 108         <para>
 109             <constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to an
 110             enabled array or the element array and the buffer object's data store is currently mapped.
 111         </para>
 112     </refsect1>
 113     <refsect1 id="seealso"><title>See Also</title>
 114         <para>
 115             <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
 116             <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>,
 117             <citerefentry><refentrytitle>glDrawRangeElementsBaseVertex</refentrytitle></citerefentry>,
 118             <citerefentry><refentrytitle>glDrawElementsInstanced</refentrytitle></citerefentry>,
 119             <citerefentry><refentrytitle>glDrawElementsInstancedBaseVertex</refentrytitle></citerefentry>
 120         </para>
 121     </refsect1>
 122     <refsect1 id="Copyright"><title>Copyright</title>
 123         <para>
 124             Copyright <trademark class="copyright"></trademark> 2010 Khronos Group.
 125             This material may be distributed subject to the terms and conditions set forth in
 126             the Open Publication License, v 1.0, 8 June 1999.
 127             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 128         </para>
 129     </refsect1>
 130 </refentry>