upstream-man-pages/man3/xhtml/glDrawElements.xml

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   4 <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glDrawElements</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glDrawElements"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDrawElements — render primitives from array data</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glDrawElements</b>(</code></td><td>GLenum  </td><td><var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLsizei  </td><td><var class="pdparam">count</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">type</var>, </td></tr><tr><td> </td><td>const GLvoid *  </td><td><var class="pdparam">indices</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>mode</code></em></span></dt><dd><p>
   5                     Specifies what kind of primitives to render.
   6                     Symbolic constants
   7                     <code class="constant">GL_POINTS</code>,
   8                     <code class="constant">GL_LINE_STRIP</code>,
   9                     <code class="constant">GL_LINE_LOOP</code>,
  10                     <code class="constant">GL_LINES</code>,
  11                     <code class="constant">GL_LINE_STRIP_ADJACENCY</code>,
  12                     <code class="constant">GL_LINES_ADJACENCY</code>,
  13                     <code class="constant">GL_TRIANGLE_STRIP</code>,
  14                     <code class="constant">GL_TRIANGLE_FAN</code>,
  15                     <code class="constant">GL_TRIANGLES</code>,
  16                     <code class="constant">GL_TRIANGLE_STRIP_ADJACENCY</code> and
  17                     <code class="constant">GL_TRIANGLES_ADJACENCY</code>
  18                     are accepted.
  19                 </p></dd><dt><span class="term"><em class="parameter"><code>count</code></em></span></dt><dd><p>
  20                     Specifies the number of elements to be rendered.
  21                 </p></dd><dt><span class="term"><em class="parameter"><code>type</code></em></span></dt><dd><p>
  22                     Specifies the type of the values in <em class="parameter"><code>indices</code></em>. Must be one of
  23                     <code class="constant">GL_UNSIGNED_BYTE</code>, <code class="constant">GL_UNSIGNED_SHORT</code>, or
  24                     <code class="constant">GL_UNSIGNED_INT</code>.
  25                 </p></dd><dt><span class="term"><em class="parameter"><code>indices</code></em></span></dt><dd><p>
  26                     Specifies a pointer to the location where the indices are stored.
  27                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  28             <code class="function">glDrawElements</code> specifies multiple geometric primitives
  29             with very few subroutine calls. Instead of calling a GL function
  30             to pass each individual vertex, normal, texture coordinate, edge
  31             flag, or color, you can prespecify
  32             separate arrays of vertices, normals, and so on, and use them to
  33             construct a sequence of primitives with a single
  34             call to <code class="function">glDrawElements</code>.
  35         </p><p>
  36             When <code class="function">glDrawElements</code> is called, it uses <em class="parameter"><code>count</code></em> sequential elements from an
  37             enabled array, starting at <em class="parameter"><code>indices</code></em> to construct a sequence of
  38             geometric primitives. <em class="parameter"><code>mode</code></em> specifies what kind of primitives are
  39             constructed and how the array elements construct these primitives. If
  40             more than one array is enabled, each is used.
  41         </p><p>
  42             Vertex attributes that are modified by <code class="function">glDrawElements</code> have an
  43             unspecified value after <code class="function">glDrawElements</code> returns.  Attributes that aren't
  44             modified maintain their previous values.
  45         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
  46             <code class="constant">GL_LINE_STRIP_ADJACENCY</code>,
  47             <code class="constant">GL_LINES_ADJACENCY</code>,
  48             <code class="constant">GL_TRIANGLE_STRIP_ADJACENCY</code> and
  49             <code class="constant">GL_TRIANGLES_ADJACENCY</code>
  50             are available only if the GL version is 3.2 or greater.
  51         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  52             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not an accepted value.
  53         </p><p>
  54             <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>count</code></em> is negative.
  55         </p><p>
  56             <code class="constant">GL_INVALID_OPERATION</code> is generated if a geometry shader is active and <em class="parameter"><code>mode</code></em>
  57             is incompatible with the input primitive type of the geometry shader in the currently installed program object.
  58         </p><p>
  59             <code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to an
  60             enabled array or the element array and the buffer object's data store is currently mapped.
  61         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
  62             <a href="glDrawArrays.xml"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
  63             <a href="glDrawElementsInstanced.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElementsInstanced</span></span></a>,
  64             <a href="glDrawElementsBaseVertex.xml"><span class="citerefentry"><span class="refentrytitle">glDrawElementsBaseVertex</span></span></a>,
  65             <a href="glDrawRangeElements.xml"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a>
  66         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
  67             Copyright <span class="trademark"></span>© 1991-2006
  68             Silicon Graphics, Inc. This document is licensed under the SGI
  69             Free Software B License. For details, see
  70             <a href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
  71         </p></div></div></body></html>