<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN" "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd"> <refentry id="glCullFace"> <refmeta> <refmetainfo> <copyright> <year>1991-2006</year> <holder>Silicon Graphics, Inc.</holder> </copyright> </refmetainfo> <refentrytitle>glCullFace</refentrytitle> <manvolnum>3G</manvolnum> </refmeta> <refnamediv> <refname>glCullFace</refname> <refpurpose>specify whether front- or back-facing polygons can be culled</refpurpose> </refnamediv> <refsynopsisdiv><title>C Specification</title> <funcsynopsis> <funcprototype> <funcdef>void <function>glCullFace</function></funcdef> <paramdef>GLenum <parameter>mode</parameter></paramdef> </funcprototype> </funcsynopsis> </refsynopsisdiv> <refsect1 id="parameters"><title>Parameters</title> <variablelist> <varlistentry> <term><parameter>mode</parameter></term> <listitem> <para> Specifies whether front- or back-facing polygons are candidates for culling. Symbolic constants <constant>GL_FRONT</constant>, <constant>GL_BACK</constant>, and <constant>GL_FRONT_AND_BACK</constant> are accepted. The initial value is <constant>GL_BACK</constant>. </para> </listitem> </varlistentry> </variablelist> </refsect1> <refsect1 id="description"><title>Description</title> <para> <function>glCullFace</function> specifies whether front- or back-facing polygons are culled (as specified by <emphasis>mode</emphasis>) when polygon culling is enabled. Polygon culling is initially disabled. To enable and disable polygon culling, call the <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry> commands with the argument <constant>GL_CULL_FACE</constant>. </para> <para> <citerefentry><refentrytitle>glFrontFace</refentrytitle></citerefentry> specifies which of the clockwise and counterclockwise polygons are front-facing and back-facing. See <citerefentry><refentrytitle>glFrontFace</refentrytitle></citerefentry>. </para> </refsect1> <refsect1 id="notes"><title>Notes</title> <para> If <parameter>mode</parameter> is <constant>GL_FRONT_AND_BACK</constant>, no polygons are drawn, but other primitives such as points and lines are drawn. </para> </refsect1> <refsect1 id="errors"><title>Errors</title> <para> <constant>GL_INVALID_ENUM</constant> is generated if <parameter>mode</parameter> is not an accepted value. </para> </refsect1> <refsect1 id="associatedgets"><title>Associated Gets</title> <para> <citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_CULL_FACE</constant> </para> <para> <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_CULL_FACE_MODE</constant> </para> </refsect1> <refsect1 id="seealso"><title>See Also</title> <para> <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glFrontFace</refentrytitle></citerefentry> </para> </refsect1> <refsect1 id="copyright"><title>Copyright</title> <para> Copyright <trademark class="copyright"></trademark> 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>. </para> </refsect1> </refentry>