<div class="refentry" lang="en" xml:lang="en"><a id="glCullFace"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glCullFace — specify whether front- or back-facing facets can be culled</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table><tr><td><code class="funcdef">void <b class="fsfunc">glCullFace</b>(</code></td><td>GLenum  </td><td><var class="pdparam">mode</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>

Specifies whether front- or back-facing facets are candidates for culling.

Symbolic constants

<code class="constant">GL_FRONT</code>, <code class="constant">GL_BACK</code>, and <code class="constant">GL_FRONT_AND_BACK</code> are accepted.

The initial value is <code class="constant">GL_BACK</code>.

</p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>

<code class="function">glCullFace</code> specifies whether front- or back-facing facets are culled

(as specified by <span class="emphasis"><em>mode</em></span>) when facet culling is enabled. Facet

culling is initially disabled.

To enable and disable facet culling, call the

<a class="citerefentry" href="glEnable"><span class="citerefentry"><span class="refentrytitle">glEnable</span></span></a> and <a class="citerefentry" href="glDisable"><span class="citerefentry"><span class="refentrytitle">glDisable</span></span></a> commands

with the argument <code class="constant">GL_CULL_FACE</code>.

Facets include triangles,

quadrilaterals,

polygons, and

rectangles.

</p><p>

<a class="citerefentry" href="glFrontFace"><span class="citerefentry"><span class="refentrytitle">glFrontFace</span></span></a> specifies which of the clockwise and counterclockwise facets

are front-facing and back-facing.

See <a class="citerefentry" href="glFrontFace"><span class="citerefentry"><span class="refentrytitle">glFrontFace</span></span></a>.

</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>

If <em class="parameter"><code>mode</code></em> is <code class="constant">GL_FRONT_AND_BACK</code>, no facets are drawn, but other

primitives such as points and lines are drawn.

</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><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 <code class="function">glCullFace</code>

is executed between the execution of <a class="citerefentry" href="glBegin"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>

and the corresponding execution of <a class="citerefentry" href="glEnd"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.

</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>

<a class="citerefentry" href="glIsEnabled"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_CULL_FACE</code>

</p><p>

<a class="citerefentry" href="glGet"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_CULL_FACE_MODE</code>

</p></div>

{$pipelinestall}{$examples}

<div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>

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

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

</p></div><div class="refsect1" lang="en" xml:lang="en"><div id="Copyright"><h2>Copyright</h2><p>

Copyright © 1991-2006

Silicon Graphics, Inc. This document is licensed under the SGI

Free Software B License. For details, see

<a class="ulink" 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></div>