<div class="refentry" id="glActiveTexture">

<div class="titlepage"></div>

<div class="refnamediv">

<h2>Name</h2>

<p>glActiveTexture — select active texture unit</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">glActiveTexture</strong>(</code>

</td>

<td>GLenum <var class="pdparam">texture</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>texture</code>

</em>

</span>

</dt>

<dd>

<p>

Specifies which texture unit to make active. The number

of texture units is implementation-dependent, but must be at least

32. <em class="parameter"><code>texture</code></em> must be one of

<code class="constant">GL_TEXTURE</code><span class="emphasis"><em>i</em></span>,

where <span class="emphasis"><em>i</em></span> ranges from zero to the

value of

<code class="constant">GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS</code>

minus one. The initial value is

<code class="constant">GL_TEXTURE0</code>.

</p>

</dd>

</dl>

</div>

</div>

<div class="refsect1" id="description">

<h2>Description</h2>

<p>

<code class="function">glActiveTexture</code> selects which texture unit subsequent texture state calls will

affect. The number of texture units an implementation supports is

implementation-dependent, but must be at least 32.

</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>texture</code></em> is not one of

<code class="constant">GL_TEXTURE</code><span class="emphasis"><em>i</em></span>, where

<span class="emphasis"><em>i</em></span> ranges from zero to the value of

<code class="constant">GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS</code> minus

one.

</p>

</div>

<div class="refsect1" id="associatedgets">

<h2>Associated Gets</h2>

<p>

<a class="citerefentry" href="glGet"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_ACTIVE_TEXTURE</code>, or <code class="constant">GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS</code>.

</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 ; ">glActiveTexture</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="glGenTextures"><span class="citerefentry"><span class="refentrytitle">glGenTextures</span></span></a>,

<a class="citerefentry" href="glBindTexture"><span class="citerefentry"><span class="refentrytitle">glBindTexture</span></span></a>,

<a class="citerefentry" href="glCompressedTexImage2D"><span class="citerefentry"><span class="refentrytitle">glCompressedTexImage2D</span></span></a>,

<a class="citerefentry" href="glCompressedTexImage3D"><span class="citerefentry"><span class="refentrytitle">glCompressedTexImage3D</span></span></a>,

<a class="citerefentry" href="glCompressedTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glCompressedTexSubImage2D</span></span></a>,

<a class="citerefentry" href="glCompressedTexSubImage3D"><span class="citerefentry"><span class="refentrytitle">glCompressedTexSubImage3D</span></span></a>,

<a class="citerefentry" href="glCopyTexImage2D"><span class="citerefentry"><span class="refentrytitle">glCopyTexImage2D</span></span></a>,

<a class="citerefentry" href="glCopyTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage2D</span></span></a>,

<a class="citerefentry" href="glCopyTexSubImage3D"><span class="citerefentry"><span class="refentrytitle">glCopyTexSubImage3D</span></span></a>,

<a class="citerefentry" href="glDeleteTextures"><span class="citerefentry"><span class="refentrytitle">glDeleteTextures</span></span></a>

<a class="citerefentry" href="glIsTexture"><span class="citerefentry"><span class="refentrytitle">glIsTexture</span></span></a>,

<a class="citerefentry" href="glTexImage2D"><span class="citerefentry"><span class="refentrytitle">glTexImage2D</span></span></a>,

<a class="citerefentry" href="glTexImage3D"><span class="citerefentry"><span class="refentrytitle">glTexImage3D</span></span></a>,

<a class="citerefentry" href="glTexSubImage2D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage2D</span></span></a>,

<a class="citerefentry" href="glTexSubImage3D"><span class="citerefentry"><span class="refentrytitle">glTexSubImage3D</span></span></a>,

<a class="citerefentry" href="glTexParameter"><span class="citerefentry"><span class="refentrytitle">glTexParameter</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>