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glDrawArraysIndirect.xhtml
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<div class="refentry" id="glDrawArraysIndirect">
<div class="titlepage"></div>
<div class="refnamediv">
<h2>Name</h2>
<p>glDrawArraysIndirect — render primitives from array data, taking parameters from memory</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">glDrawArraysIndirect</strong>(</code>
</td>
<td>GLenum <var class="pdparam">mode</var>, </td>
</tr>
<tr>
<td> </td>
<td>const void *<var class="pdparam">indirect</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>indirect</code>
</em>
</span>
</dt>
<dd>
<p>
Specifies the address of a structure containing the draw parameters.
</p>
</dd>
</dl>
</div>
</div>
<div class="refsect1" id="description">
<h2>Description</h2>
<p>
<code class="function">glDrawArraysIndirect</code> specifies multiple geometric primitives
with very few subroutine calls. <code class="function">glDrawArraysIndirect</code> behaves
similarly to <a class="citerefentry" href="glDrawArraysInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>,
except that the parameters to <a class="citerefentry" href="glDrawArraysInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>
are stored in memory at the address given by <em class="parameter"><code>indirect</code></em>.
</p>
<p>
The parameters addressed by <em class="parameter"><code>indirect</code></em> are packed into a structure
that takes the form (in C):
</p>
<pre class="programlisting"> typedef struct {
uint count;
uint primCount;
uint first;
uint reserved;
} DrawArraysIndirectCommand;
const DrawArraysIndirectCommand *cmd = (const DrawArraysIndirectCommand *)indirect;
glDrawArraysInstanced(mode, cmd->first, cmd->count, cmd->primCount);</pre>
<p>
</p>
<p>
If a buffer is bound to the <code class="constant">GL_DRAW_INDIRECT_BUFFER</code> binding at the time
of a call to <code class="function">glDrawArraysIndirect</code>, <em class="parameter"><code>indirect</code></em>
is interpreted as an offset, in basic machine units, into that buffer and the parameter
data is read from the buffer rather than from client memory.
</p>
<p>
In contrast to <a class="citerefentry" href="glDrawArraysInstanced"><span class="citerefentry"><span class="refentrytitle">glDrawArraysInstanced</span></span></a>,
the <code class="code">first</code> member of the parameter structure is unsigned, and out-of-range indices
do not generate an error.
</p>
<p>
Vertex attributes that are modified by <code class="function">glDrawArraysIndirect</code> have an
unspecified value after <code class="function">glDrawArraysIndirect</code> returns. Attributes that aren't
modified remain well defined.
</p>
</div>
<div class="refsect1" id="notes">
<h2>Notes</h2>
<p>
The <em class="parameter"><code>reserved</code></em> member of the <em class="parameter"><code>DrawArraysIndirectCommand</code></em>
structure should be set to zero. Behavior is undefined if it is non-zero.
</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_OPERATION</code> is generated if a non-zero buffer object name is bound to an
enabled array or to the <code class="constant">GL_DRAW_INDIRECT_BUFFER</code> binding and the buffer object's data store is currently mapped.
</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 ; ">
<code class="function">glDrawArraysIndirect</code>
</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="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="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
<a class="citerefentry" href="glDrawRangeElements"><span class="citerefentry"><span class="refentrytitle">glDrawRangeElements</span></span></a>,
</p>
</div>
<div class="refsect1" id="Copyright">
<h2>Copyright</h2>
<p>
Copyright © 2010-2014 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
<a class="link" href="https://opencontent.org/openpub/" target="_top">https://opencontent.org/openpub/</a>.
</p>
</div>
</div>