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<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glPushMatrix</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glPushMatrix"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glPushMatrix — push and pop the current matrix stack</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glPushMatrix</b>(</code></td><td>  </td><td><var class="pdparam">void</var><code>)</code>;</td></tr></table></div></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glPopMatrix</b>(</code></td><td>  </td><td><var class="pdparam">void</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
            There is a stack of matrices for each of the matrix modes.
            In <code class="constant">GL_MODELVIEW</code> mode,
            the stack depth is at least 32.
            In the other modes,
            <code class="constant">GL_COLOR</code>, <code class="constant">GL_PROJECTION</code>, and <code class="constant">GL_TEXTURE</code>,
            the depth is at least 2.
            The current matrix in any mode is the matrix on the top of the stack
            for that mode.
        </p><p>
            <code class="function">glPushMatrix</code> pushes the current matrix stack down by one,
            duplicating the current matrix.
            That is,
            after a <code class="function">glPushMatrix</code> call,
            the matrix on top of the stack is identical to the one below it.
        </p><p>
            <a class="citerefentry" href="glPopMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glPopMatrix</span></span></a> pops the current matrix stack,
            replacing the current matrix with the one below it on the stack.
        </p><p>
            Initially, each of the stacks contains one matrix, an identity matrix.
        </p><p>
            It is an error to push a full matrix stack
            or to pop a matrix stack that contains only a single matrix.
            In either case, the error flag is set
            and no other change is made to GL state.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GL_STACK_OVERFLOW</code> is generated if <code class="function">glPushMatrix</code> is called while
            the current matrix stack is full.
        </p><p>
            <code class="constant">GL_STACK_UNDERFLOW</code> is generated if <a class="citerefentry" href="glPopMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glPopMatrix</span></span></a> is called while
            the current matrix stack contains only a single matrix.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glPushMatrix</code> or <a class="citerefentry" href="glPopMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glPopMatrix</span></span></a>
            is executed between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>
            and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MATRIX_MODE</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_COLOR_MATRIX</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MODELVIEW_MATRIX</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PROJECTION_MATRIX</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_TEXTURE_MATRIX</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_COLOR_MATRIX_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MODELVIEW_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_PROJECTION_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_TEXTURE_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_MODELVIEW_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_PROJECTION_STACK_DEPTH</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_TEXTURE_STACK_DEPTH</code>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glFrustum.xml"><span class="citerefentry"><span class="refentrytitle">glFrustum</span></span></a>,
            <a class="citerefentry" href="glLoadIdentity.xml"><span class="citerefentry"><span class="refentrytitle">glLoadIdentity</span></span></a>,
            <a class="citerefentry" href="glLoadMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glLoadMatrix</span></span></a>,
            <a class="citerefentry" href="glLoadTransposeMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glLoadTransposeMatrix</span></span></a>,
            <a class="citerefentry" href="glMatrixMode.xml"><span class="citerefentry"><span class="refentrytitle">glMatrixMode</span></span></a>,
            <a class="citerefentry" href="glMultMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glMultMatrix</span></span></a>,
            <a class="citerefentry" href="glMultTransposeMatrix.xml"><span class="citerefentry"><span class="refentrytitle">glMultTransposeMatrix</span></span></a>,
            <a class="citerefentry" href="glOrtho.xml"><span class="citerefentry"><span class="refentrytitle">glOrtho</span></span></a>,
            <a class="citerefentry" href="glRotate.xml"><span class="citerefentry"><span class="refentrytitle">glRotate</span></span></a>,
            <a class="citerefentry" href="glScale.xml"><span class="citerefentry"><span class="refentrytitle">glScale</span></span></a>,
            <a class="citerefentry" href="glTranslate.xml"><span class="citerefentry"><span class="refentrytitle">glTranslate</span></span></a>,
            <a class="citerefentry" href="glViewport.xml"><span class="citerefentry"><span class="refentrytitle">glViewport</span></span></a>
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p></div></div></body></html>
