
<refentry id="glLoadIdentity">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glLoadIdentity</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glLoadIdentity</refname>
        <refpurpose>replace the current matrix with the identity matrix</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glLoadIdentity</function></funcdef>
                <paramdef> <parameter>void</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>glLoadIdentity</function> replaces the current matrix with the identity matrix.
            It is semantically equivalent to calling <citerefentry><refentrytitle>glLoadMatrix</refentrytitle></citerefentry>
            with the identity matrix
        </para>
        <para>
        </para>
        <para>
            <informalequation><mml:math>
                <!-- eqn: left (  {   matrix {    lcol { 1 above 0 above 0 above 0  }    lcol { 0 above 1 above 0 above 0  }    lcol { 0 above 0 above 1 above 0  }    lcol { 0 above 0 above 0 above 1 } } }    right ):-->
                <mml:mfenced open="(" close=")">
                    <mml:mfenced open="" close="">
                        <mml:mtable>
                            <mml:mtr>
                                <mml:mtd>
                                    <mml:mn>1</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                            </mml:mtr>
                            <mml:mtr>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>1</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                            </mml:mtr>
                            <mml:mtr>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>1</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                            </mml:mtr>
                            <mml:mtr>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>0</mml:mn>
                                </mml:mtd>
                                <mml:mtd>
                                    <mml:mn>1</mml:mn>
                                </mml:mtd>
                            </mml:mtr>
                        </mml:mtable>
                    </mml:mfenced>
                </mml:mfenced>
            </mml:math></informalequation>
        </para>
        <para>
        </para>
        <para>
            but in some cases it is more efficient.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_OPERATION</constant> is generated if <function>glLoadIdentity</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>glGet</refentrytitle></citerefentry> with argument <constant>GL_MATRIX_MODE</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_COLOR_MATRIX</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MODELVIEW_MATRIX</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_PROJECTION_MATRIX</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_TEXTURE_MATRIX</constant>
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glLoadMatrix</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glLoadTransposeMatrix</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMultMatrix</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glMultTransposeMatrix</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glPushMatrix</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>
