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<refentry id="glVertexPointer">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glVertexPointer</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glVertexPointer</refname>
        <refpurpose>define an array of vertex data</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glVertexPointer</function></funcdef>
                <paramdef>GLint <parameter>size</parameter></paramdef>
                <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>size</parameter></term>
            <listitem>
                <para>
                    Specifies the number of coordinates per vertex. Must be 2, 3, or
                    4. The initial value is 4.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>type</parameter></term>
            <listitem>
                <para>
                    Specifies the data type of each coordinate in the array.
                    Symbolic constants
                    <constant>GL_SHORT</constant>,
                    <constant>GL_INT</constant>,
                    <constant>GL_FLOAT</constant>,
                    or <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
                    vertices. If <parameter>stride</parameter> is 0, the vertices 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 coordinate of the first vertex in the
                    array. The initial value is 0.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glVertexPointer</function> specifies the location and data format of an array of vertex coordinates
            to use when rendering.
            <parameter>size</parameter> specifies the number of coordinates per vertex, and must be 2, 3, or 4.
            <parameter>type</parameter> specifies the data type of each coordinate, and <parameter>stride</parameter> specifies the byte stride from one
            vertex to the next, allowing vertices and attributes
            to be packed into a single array or stored in separate arrays.
            (Single-array storage may be more efficient on some implementations;
            see <citerefentry><refentrytitle>glInterleavedArrays</refentrytitle></citerefentry>.)
        </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 vertex 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 vertex array
            client-side state (<constant>GL_VERTEX_ARRAY_BUFFER_BINDING</constant>).
        </para>
        <para>
            When a vertex array is specified,
            <parameter>size</parameter>, <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 vertex array, call <citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry> and
            <citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry> with the argument <constant>GL_VERTEX_ARRAY</constant>. If
            enabled, the vertex array is used when
            <citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glMultiDrawArrays</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>, <citerefentry><refentrytitle>glMultiDrawElements</refentrytitle></citerefentry>, or <citerefentry><refentrytitle>glDrawRangeElements</refentrytitle></citerefentry>
            is called.
        </para>
    </refsect1>
    <refsect1 id="notes"><title>Notes</title>
        <para>
            <function>glVertexPointer</function> is available only if the GL version is 1.1 or greater.
        </para>
        <para>
            The vertex 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>glVertexPointer</function> is not allowed between the execution of
            <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry> and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>,
            but an error may or may not be generated. If no error is generated,
            the operation is undefined.
        </para>
        <para>
            <function>glVertexPointer</function> is typically implemented on the client side.
        </para>
        <para>
            Vertex 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_VALUE</constant> is generated if <parameter>size</parameter> is not 2, 3, or 4.
        </para>
        <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_VERTEX_ARRAY</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_VERTEX_ARRAY_SIZE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_VERTEX_ARRAY_TYPE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_VERTEX_ARRAY_STRIDE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_VERTEX_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_VERTEX_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>glIndexPointer</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>glVertex</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glVertexAttribPointer</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>