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glDrawElements.xhtml
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glDrawElements.xhtml
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<div class="refentry" id="glDrawElements">
<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 style="border: 0; cellspacing: 0; cellpadding: 0;" class="funcprototype-table">
<tr>
<td>
<code class="funcdef">void <strong class="fsfunc">glDrawElements</strong>(</code>
</td>
<td>GLenum <var class="pdparam">mode</var>, </td>
</tr>
<tr>
<td> </td>
<td>GLsizei <var class="pdparam">count</var>, </td>
</tr>
<tr>
<td> </td>
<td>GLenum <var class="pdparam">type</var>, </td>
</tr>
<tr>
<td> </td>
<td>const GLvoid * <var class="pdparam">indices</var><code>)</code>;</td>
</tr>
</table>
<div class="funcprototype-spacer"> </div>
</div>
</div>
<div class="refsect1" id="parameters">
<h2>Parameters</h2>
<div class="variablelist">
<dl class="variablelist">
<dt>
<span class="term">
<em class="parameter">
<code>mode</code>
</em>
</span>
</dt>
<dd>
<p>
Specifies what kind of primitives to render.
Symbolic constants
<code class="constant">GL_POINTS</code>,
<code class="constant">GL_LINE_STRIP</code>,
<code class="constant">GL_LINE_LOOP</code>,
<code class="constant">GL_LINES</code>,
<code class="constant">GL_TRIANGLE_STRIP</code>,
<code class="constant">GL_TRIANGLE_FAN</code> and
<code class="constant">GL_TRIANGLES</code>
are accepted.
</p>
</dd>
<dt>
<span class="term">
<em class="parameter">
<code>count</code>
</em>
</span>
</dt>
<dd>
<p>
Specifies the number of elements to be rendered.
</p>
</dd>
<dt>
<span class="term">
<em class="parameter">
<code>type</code>
</em>
</span>
</dt>
<dd>
<p>
Specifies the type of the values in <em class="parameter"><code>indices</code></em>. Must be one of
<code class="constant">GL_UNSIGNED_BYTE</code>, <code class="constant">GL_UNSIGNED_SHORT</code>, or
<code class="constant">GL_UNSIGNED_INT</code>.
</p>
</dd>
<dt>
<span class="term">
<em class="parameter">
<code>indices</code>
</em>
</span>
</dt>
<dd>
<p>
Specifies a byte offset (cast to a pointer type) into the buffer bound to <code class="constant">GL_ELEMENT_ARRAY_BUFFER</code>
to start reading indices from. If no buffer is bound, specifies a pointer to the location where the indices are stored.
</p>
</dd>
</dl>
</div>
</div>
<div class="refsect1" id="description">
<h2>Description</h2>
<p>
<code class="function">glDrawElements</code> specifies multiple geometric primitives
with very few subroutine calls. It is possible to prespecify
separate arrays of attributes and use them to
construct a sequence of primitives with a single
call to <code class="function">glDrawElements</code>.
</p>
<p>
When <code class="function">glDrawElements</code> is called, it uses <em class="parameter"><code>count</code></em> sequential elements from an
enabled array, starting at <em class="parameter"><code>indices</code></em> to construct a sequence of
geometric primitives. <em class="parameter"><code>mode</code></em> specifies what kind of primitives are
constructed and how the array elements construct these primitives. If
more than one array is enabled, each is used.
</p>
<p>
To enable and disable a generic vertex attribute array, call
<a class="citerefentry" href="glEnableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a> and
<a class="citerefentry" href="glDisableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>.
</p>
<p>
If an array corresponding to a generic attribute required by a vertex shader
is not enabled, then the corresponding element is taken from the current generic
attribute state.
</p>
</div>
<div class="refsect1" id="errors">
<h2>Errors</h2>
<p>
<code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not an accepted value.
</p>
<p>
<code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>count</code></em> is negative.
</p>
<p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to an
enabled array or the element array and the buffer object's data store is currently mapped.
</p>
<p>
<code class="constant">GL_INVALID_FRAMEBUFFER_OPERATION</code> is generated if the currently bound framebuffer is not
framebuffer complete (i.e. the return value from
<a class="citerefentry" href="glCheckFramebufferStatus"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a> is not <code class="constant">GL_FRAMEBUFFER_COMPLETE</code>).
</p>
<p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if transform feedback is active and not paused.
</p>
</div>
{$pipelinestall}{$examples}
<div class="refsect1" id="versions">
<h2>API Version Support</h2>
<div class="informaltable">
<table style="border-collapse: collapse; border-top: 2px solid ; border-bottom: 2px solid ; border-left: 2px solid ; border-right: 2px solid ; ">
<colgroup>
<col style="text-align: left; "/>
<col style="text-align: center; " class="firstvers"/>
<col style="text-align: center; "/>
<col style="text-align: center; " class="lastvers"/>
</colgroup>
<thead>
<tr>
<th style="text-align: left; border-right: 2px solid ; ">
</th>
<th style="text-align: center; border-bottom: 2px solid ; " colspan="3">
<span class="bold"><strong>OpenGL ES API Version</strong></span>
</th>
</tr>
<tr>
<th style="text-align: left; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>Function Name</strong></span>
</th>
<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>2.0</strong></span>
</th>
<th style="text-align: center; border-right: 2px solid ; border-bottom: 2px solid ; ">
<span class="bold"><strong>3.0</strong></span>
</th>
<th style="text-align: center; border-bottom: 2px solid ; ">
<span class="bold"><strong>3.1</strong></span>
</th>
</tr>
</thead>
<tbody>
<tr>
<td style="text-align: left; border-right: 2px solid ; ">glDrawElements</td>
<td style="text-align: center; border-right: 2px solid ; ">✔</td>
<td style="text-align: center; border-right: 2px solid ; ">✔</td>
<td style="text-align: center; ">✔</td>
</tr>
</tbody>
</table>
</div>
</div>
<div class="refsect1" id="seealso">
<h2>See Also</h2>
<p>
<a class="citerefentry" href="glCheckFramebufferStatus"><span class="citerefentry"><span class="refentrytitle">glCheckFramebufferStatus</span></span></a>,
<a class="citerefentry" href="glDisableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>,
<a class="citerefentry" href="glDrawArrays"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
<a class="citerefentry" href="glDrawArraysInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>,
<a class="citerefentry" href="glDrawElementsInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawElementsInstanced</span></span></a>,
<a class="citerefentry" href="glDrawRangeElements"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a>,
<a class="citerefentry" href="glEnableVertexAttribArray"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a>
</p>
</div>
<div class="refsect1" id="Copyright">
<h2>Copyright</h2>
<p>
Copyright © 1991-2006 Silicon Graphics, Inc.
Copyright © 2010-2014 Khronos Group.
This document is licensed under the SGI Free Software B License.
For details, see
<a class="link" href="https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/" target="_top">https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/</a>.
</p>
</div>
</div>