
<refentry id="gluOrtho2D">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>gluOrtho2D</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>gluOrtho2D</refname>
        <refpurpose>define a 2D orthographic projection matrix</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>gluOrtho2D</function></funcdef>
                <paramdef>GLdouble <parameter>left</parameter></paramdef>
                <paramdef>GLdouble <parameter>right</parameter></paramdef>
                <paramdef>GLdouble <parameter>bottom</parameter></paramdef>
                <paramdef>GLdouble <parameter>top</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <!-- eqn: ignoring delim $$ -->
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>left</parameter></term>
            <term><parameter>right</parameter></term>
            <listitem>
                <para>
                    Specify the coordinates for the left and right vertical clipping planes.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>bottom</parameter></term>
            <term><parameter>top</parameter></term>
            <listitem>
                <para>
                    Specify the coordinates for the bottom and top horizontal clipping planes.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>gluOrtho2D</function> sets up a two-dimensional orthographic viewing region.  
            This is equivalent to calling <citerefentry><refentrytitle>glOrtho</refentrytitle></citerefentry> with 
            <inlineequation><mml:math>
                <!-- eqn: near  =  -1:-->
                <mml:mrow>
                    <mml:mi mathvariant="italic">near</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mn>-1</mml:mn>
                </mml:mrow>
            </mml:math></inlineequation>
            and 
            <inlineequation><mml:math>
                <!-- eqn: far  =  1:-->
                <mml:mrow>
                    <mml:mi mathvariant="italic">far</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mn>1</mml:mn>
                </mml:mrow>
            </mml:math></inlineequation>.
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glOrtho</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluPerspective</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>
