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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>glGetClipPlane</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glGetClipPlane"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetClipPlane — return the coefficients of the specified clipping
    plane</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetClipPlanef</strong>(</code></td><td>GLenum <var class="pdparam">plane</var>, </td></tr><tr><td> </td><td>GLfloat *<var class="pdparam">equation</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glGetClipPlanex</strong>(</code></td><td>GLenum <var class="pdparam">plane</var>, </td></tr><tr><td> </td><td>GLfixed *<var class="pdparam">equation</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>plane</code></em></span></dt><dd><p>Specifies a clipping plane. The number of clipping planes
          depends on the implementation, but at least six clipping planes are
          supported. Symbolic names of the form
          <code class="constant">GL_CLIP_PLANE</code> <span class="emphasis"><em>i</em></span>, where
          <span class="emphasis"><em>i</em></span> is an integer between 0 and
          <code class="constant">GL_MAX_CLIP_PLANES</code> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                

                <mml:mn>-1</mml:mn>
              </mml:math>, are accepted.</p></dd><dt><span class="term"><em class="parameter"><code>equation</code></em></span></dt><dd><p>Returns four fixed-point or floating-point values that are the
          coefficients of the plane equation of <em class="parameter"><code>plane</code></em>
          in eye coordinates in the order <span class="emphasis"><em>p1</em></span>,
          <span class="emphasis"><em>p2</em></span>, <span class="emphasis"><em>p3</em></span>, and
          <span class="emphasis"><em>p4</em></span>. The initial value is (0, 0, 0, 0).</p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p><code class="function">glGetClipPlane</code> returns in
    <em class="parameter"><code>equation</code></em> the four coefficients of the plane
    equation for <em class="parameter"><code>plane</code></em>. The coefficients are in eye
    coordinates and are returned in the order <span class="emphasis"><em>p1</em></span>,
    <span class="emphasis"><em>p2</em></span>, <span class="emphasis"><em>p3</em></span>, and
    <span class="emphasis"><em>p4</em></span>.</p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>It is always the case that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
           

          <mml:mi>GL_CLIP_PLANEi</mml:mi>

          <mml:mo>=</mml:mo>

           

          <mml:mi>GL_CLIP_PLANE0</mml:mi>

          <mml:mo>+</mml:mo>

          <code class="constant">i</code>

          . 
        </mml:math></p><p>If an error is generated, no change is made to the contents of
    <em class="parameter"><code>equation</code></em>.</p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p><code class="constant">GL_INVALID_ENUM</code> is generated if
    <em class="parameter"><code>plane</code></em> is not an accepted value.</p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p><a class="citerefentry" href="glClipPlane.xml"><span class="citerefentry"><span class="refentrytitle">glClipPlane</span></span></a></p></div><div class="refsect1"><a id="copyright"></a><h2>Copyright</h2><p>Copyright <span class="trademark"></span>© 2003-2004
    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>