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<refentry id="glIndexPointer">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glIndexPointer</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glIndexPointer</refname>
        <refpurpose>define an array of color indexes</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glIndexPointer</function></funcdef>
                <paramdef>GLenum <parameter>type</parameter></paramdef>
                <paramdef>GLsizei <parameter>stride</parameter></paramdef>
                <paramdef>const GLvoid * <parameter>pointer</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <!-- eqn: ignoring delim $$ -->
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>type</parameter></term>
            <listitem>
                <para>
                    Specifies the data type of each color index in the array.
                    Symbolic constants
                    <constant>GL_UNSIGNED_BYTE</constant>,
                    <constant>GL_SHORT</constant>,
                    <constant>GL_INT</constant>,
                    <constant>GL_FLOAT</constant>,
                    and <constant>GL_DOUBLE</constant>
                    are accepted. The initial value is <constant>GL_FLOAT</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>stride</parameter></term>
            <listitem>
                <para>
                    Specifies the byte offset between consecutive color indexes.
                    If <parameter>stride</parameter> is 0, the color indexes are understood to
                    be tightly packed in the array. The initial value is 0.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>pointer</parameter></term>
            <listitem>
                <para>
                    Specifies a pointer to the first index in the array.
                    The initial value is 0.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glIndexPointer</function> specifies the location and data format of an array of color indexes
            to use when rendering.
            <parameter>type</parameter> specifies the data type of
            each color index and <parameter>stride</parameter> specifies the byte stride from one
            color index to the next, allowing vertices and attributes
            to be packed into a single array or stored in separate arrays.
        </para>
        <para>
            If a non-zero named buffer object is bound to the <constant>GL_ARRAY_BUFFER</constant> target 
            (see <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>) while a color index array is
            specified, <parameter>pointer</parameter> is treated as a byte offset into the buffer object's data store.
            Also, the buffer object binding (<constant>GL_ARRAY_BUFFER_BINDING</constant>) is saved as color index vertex array
            client-side state (<constant>GL_INDEX_ARRAY_BUFFER_BINDING</constant>).
        </para>
        <para>
            When a color index array is specified,
            <parameter>type</parameter>, <parameter>stride</parameter>, and <parameter>pointer</parameter> are saved as client-side
            state, in addition to the current vertex array buffer object binding.
        </para>
        <para>
            To enable and disable the color index array, call
            <citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry> with the argument
            <constant>GL_INDEX_ARRAY</constant>. If
            enabled, the color index array is used
            when <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glMultiDrawArrays</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMultiDrawElements</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>, or
            <citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry> is called.
        </para>
    </refsect1>
    <refsect1 id="notes"><title>Notes</title>
        <para>
            <function>glIndexPointer</function> is available only if the GL version is 1.1 or greater.
        </para>
        <para>
            Color indexes are not supported for interleaved vertex array formats
            (see <citerefentry><refentrytitle>glInterleavedArrays</refentrytitle></citerefentry>).
        </para>
        <para>
            The color index array is initially disabled and isn't accessed when
            <citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glMultiDrawArrays</refentrytitle></citerefentry>, or <citerefentry><refentrytitle>glMultiDrawElements</refentrytitle></citerefentry>
            is called.
        </para>
        <para>
            Execution of <function>glIndexPointer</function> is not allowed between
            <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry> and the corresponding <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>,
            but an error may or may not be generated. If an error is not generated,
            the operation is undefined.
        </para>
        <para>
            <function>glIndexPointer</function> is typically implemented on the client side.
        </para>
        <para>
            Color index array parameters are client-side state and are
            therefore not saved or restored by <citerefentry><refentrytitle>glPushAttrib</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glPopAttrib</refentrytitle></citerefentry>.
            Use <citerefentry><refentrytitle>glPushClientAttrib</refentrytitle></citerefentry> and
            <citerefentry><refentrytitle>glPopClientAttrib</refentrytitle></citerefentry> instead.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if <parameter>type</parameter> is not an accepted value.
        </para>
        <para>
            <constant>GL_INVALID_VALUE</constant> is generated if <parameter>stride</parameter> is negative.
        </para>
    </refsect1>
    <refsect1 id="associatedgets"><title>Associated Gets</title>
        <para>
            <citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_INDEX_ARRAY</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_INDEX_ARRAY_TYPE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_INDEX_ARRAY_STRIDE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_INDEX_ARRAY_BUFFER_BINDING</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_ARRAY_BUFFER_BINDING</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGetPointerv</refentrytitle></citerefentry> with argument <constant>GL_INDEX_ARRAY_POINTER</constant>
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glBindBuffer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glColorPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glEdgeFlagPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glFogCoordPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glInterleavedArrays</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMultiDrawArrays</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMultiDrawElements</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glNormalPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glPopClientAttrib</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glPushClientAttrib</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glSecondaryColorPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glTexCoordPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glVertexAttribPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glVertexPointer</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>
