
<refentry id="glPushClientAttrib">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glPushClientAttrib</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glPushClientAttrib</refname>
        <refpurpose>push and pop the client attribute stack</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glPushClientAttrib</function></funcdef>
                <paramdef>GLbitfield <parameter>mask</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>mask</parameter></term>
            <listitem>
                <para>
                    Specifies a mask that indicates which attributes to save.  Values for
                    <parameter>mask</parameter> are listed below.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glPopClientAttrib</function></funcdef>
                <paramdef> <parameter>void</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glPushClientAttrib</function> takes one argument,
            a mask that indicates which groups of client-state variables
            to save on the client attribute stack.
            Symbolic constants are used to set bits in the mask.
            <parameter>mask</parameter>
            is typically constructed by specifying the bitwise-or of several 
	    of these constants together.
            The special mask
            <constant>GL_CLIENT_ALL_ATTRIB_BITS</constant>
            can be used to save all stackable client state.
        </para>
        <para>
            The symbolic mask constants and their associated GL client state are as follows
            (the second column lists which attributes are saved):
        </para>
        <para>
            <constant>GL_CLIENT_PIXEL_STORE_BIT</constant>	Pixel storage modes
            <constant>GL_CLIENT_VERTEX_ARRAY_BIT</constant>	Vertex arrays (and enables)
        </para>
        <para>
            <citerefentry><refentrytitle>glPopClientAttrib</refentrytitle></citerefentry> restores the values of the client-state variables
            saved with the last <function>glPushClientAttrib</function>.
            Those not saved are left unchanged.
        </para>
        <para>
            It is an error to push attributes onto a full client attribute stack
            or to pop attributes off an empty stack.
            In either case, the error flag is set,
            and no other change is made to GL state.
        </para>
        <para>
            Initially, the client attribute stack is empty.
        </para>
    </refsect1>
    <refsect1 id="notes"><title>Notes</title>
        <para>
            <function>glPushClientAttrib</function> is available only if the GL version is 1.1 or greater.
        </para>
        <para>
            Not all values for GL client state can be saved on the attribute stack.
            For example, select and feedback state cannot be saved.
        </para>
        <para>
            The depth of the attribute stack depends on the implementation,
            but it must be at least 16.
        </para>
        <para>
            Use <citerefentry><refentrytitle>glPushAttrib</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glPopAttrib</refentrytitle></citerefentry> to push and restore
            state that is kept on the server. Only pixel storage modes and
            vertex array state may be pushed and popped with
            <function>glPushClientAttrib</function> and <citerefentry><refentrytitle>glPopClientAttrib</refentrytitle></citerefentry>.
        </para>
        <para>
            For OpenGL versions 1.3 and greater, or when the <code>ARB_multitexture</code> extension is supported, pushing and
            popping client vertex array state applies to all supported texture units,
            and the active client texture state.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_STACK_OVERFLOW</constant> is generated if <function>glPushClientAttrib</function> is called while
            the attribute stack is full.
        </para>
        <para>
            <constant>GL_STACK_UNDERFLOW</constant> is generated if <citerefentry><refentrytitle>glPopClientAttrib</refentrytitle></citerefentry> is called while
            the attribute stack is empty.
        </para>
    </refsect1>
    <refsect1 id="associatedgets"><title>Associated Gets</title>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_ATTRIB_STACK_DEPTH</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_CLIENT_ATTRIB_STACK_DEPTH</constant>
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glColorPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glEdgeFlagPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glFogCoordPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glGetError</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glIndexPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glNormalPointer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glNewList</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glPixelStore</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glPushAttrib</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glTexCoordPointer</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>
