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<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 facets 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 facets 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 facets are culled
            (as specified by <emphasis>mode</emphasis>) when facet culling is enabled. Facet
            culling is initially disabled.
            To enable and disable facet culling, call the
            <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry> commands
            with the argument <constant>GL_CULL_FACE</constant>.
            Facets include triangles,
            quadrilaterals,
            polygons, and
            rectangles.
        </para>
        <para>
            <citerefentry><refentrytitle>glFrontFace</refentrytitle></citerefentry> specifies which of the clockwise and counterclockwise facets
            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 facets 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>
        <para>
            <constant>GL_INVALID_OPERATION</constant> is generated if <function>glCullFace</function>
            is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
            and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
        </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>
