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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>gluPwlCurve</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="gluPwlCurve"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>gluPwlCurve — describe a piecewise linear NURBS trimming curve</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">gluPwlCurve</b>(</code></td><td>GLUnurbs*  </td><td><var class="pdparam">nurb</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">count</var>, </td></tr><tr><td> </td><td>GLfloat*  </td><td><var class="pdparam">data</var>, </td></tr><tr><td> </td><td>GLint  </td><td><var class="pdparam">stride</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">type</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>nurb</code></em></span></dt><dd><p>
                    Specifies the NURBS object (created with <a class="citerefentry" href="gluNewNurbsRenderer.xml"><span class="citerefentry"><span class="refentrytitle">gluNewNurbsRenderer</span></span></a>).
                </p></dd><dt><span class="term"><em class="parameter"><code>count</code></em></span></dt><dd><p>
                    Specifies the number of points on the curve.
                </p></dd><dt><span class="term"><em class="parameter"><code>data</code></em></span></dt><dd><p>
                    Specifies an array containing the curve points.
                </p></dd><dt><span class="term"><em class="parameter"><code>stride</code></em></span></dt><dd><p>
                    Specifies the offset (a number of single-precision floating-point values)
                    between points on the curve.
                </p></dd><dt><span class="term"><em class="parameter"><code>type</code></em></span></dt><dd><p>
                    Specifies the type of curve.
                    Must be either <code class="constant">GLU_MAP1_TRIM_2</code> or <code class="constant">GLU_MAP1_TRIM_3</code>.
                </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
            <code class="function">gluPwlCurve</code> describes a piecewise linear trimming curve for a NURBS surface.
            A piecewise linear curve consists of a list of 
            coordinates of points in the parameter space for the
            NURBS surface to be trimmed. These points are connected
            with line segments to form a curve. If the curve is
            an approximation to a curve that is not piecewise linear, 
            the points should be close enough in parameter space that the 
            resulting path appears curved at the resolution used in the application.
        </p><p>
            If <em class="parameter"><code>type</code></em> is
            <code class="constant">GLU_MAP1_TRIM_2</code>, then it describes a curve in two-dimensional (<span class="emphasis"><em>u</em></span> 
            and <span class="emphasis"><em>v</em></span>) parameter space. If it is <code class="constant">GLU_MAP1_TRIM_3</code>, then it
            describes a curve in two-dimensional homogeneous (<span class="emphasis"><em>u</em></span>, <span class="emphasis"><em>v</em></span>,
            and <span class="emphasis"><em>w</em></span>) parameter space. 
            See the <a class="citerefentry" href="gluBeginTrim.xml"><span class="citerefentry"><span class="refentrytitle">gluBeginTrim</span></span></a> reference page for more information 
            about trimming curves. 
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
            To describe a trim curve that closely follows the contours of a NURBS 
            surface, call <a class="citerefentry" href="gluNurbsCurve.xml"><span class="citerefentry"><span class="refentrytitle">gluNurbsCurve</span></span></a>.
        </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="gluBeginCurve.xml"><span class="citerefentry"><span class="refentrytitle">gluBeginCurve</span></span></a>,
            <a class="citerefentry" href="gluBeginTrim.xml"><span class="citerefentry"><span class="refentrytitle">gluBeginTrim</span></span></a>,
            <a class="citerefentry" href="gluNewNurbsRenderer.xml"><span class="citerefentry"><span class="refentrytitle">gluNewNurbsRenderer</span></span></a>,
            <a class="citerefentry" href="gluNurbsCurve.xml"><span class="citerefentry"><span class="refentrytitle">gluNurbsCurve</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>
