<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd"><!-- saved from url=(0013)about:internet -->
<?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>gluDisk</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="gluDisk"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>gluDisk — draw a disk</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">gluDisk</strong>(</code></td><td>GLUquadric* <var class="pdparam">quad</var>, </td></tr><tr><td> </td><td>GLdouble <var class="pdparam">inner</var>, </td></tr><tr><td> </td><td>GLdouble <var class="pdparam">outer</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">slices</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">loops</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>quad</code></em></span></dt><dd><p>
                    Specifies the quadrics object (created with <a class="citerefentry" href="gluNewQuadric.xml"><span class="citerefentry"><span class="refentrytitle">gluNewQuadric</span></span></a>).
                </p></dd><dt><span class="term"><em class="parameter"><code>inner</code></em></span></dt><dd><p>
                    Specifies the inner radius of the disk (may be 0).
                </p></dd><dt><span class="term"><em class="parameter"><code>outer</code></em></span></dt><dd><p>
                    Specifies the outer radius of the disk.
                </p></dd><dt><span class="term"><em class="parameter"><code>slices</code></em></span></dt><dd><p>
                    Specifies the number of subdivisions around the <span class="emphasis"><em>z</em></span> axis.
                </p></dd><dt><span class="term"><em class="parameter"><code>loops</code></em></span></dt><dd><p>
                    Specifies the number of concentric rings about the origin into which
                    the disk is subdivided.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <code class="function">gluDisk</code> renders a disk on the <span class="emphasis"><em>z</em></span> = 0 plane. The disk has a radius of 
            <em class="parameter"><code>outer</code></em> and contains a concentric circular hole with a radius 
            of <em class="parameter"><code>inner</code></em>. If <em class="parameter"><code>inner</code></em> is 0, then no hole is generated. The disk is
            subdivided around the <span class="emphasis"><em>z</em></span> axis into slices (like pizza slices) and also
            about the <span class="emphasis"><em>z</em></span> axis into rings 
            (as specified by <em class="parameter"><code>slices</code></em> and <em class="parameter"><code>loops</code></em>, respectively).
        </p><p>
            With respect to orientation, the +<span class="emphasis"><em>z</em></span> side of the disk is considered to be 
            ``outside'' (see <a class="citerefentry" href="gluQuadricOrientation.xml"><span class="citerefentry"><span class="refentrytitle">gluQuadricOrientation</span></span></a>).
            This means that if the
            orientation is set to <code class="constant">GLU_OUTSIDE</code>, then any normals generated 
            point along the +<span class="emphasis"><em>z</em></span> axis. Otherwise, they point along the \-<span class="emphasis"><em>z</em></span> 
            axis.
        </p><p>
            If texturing has been turned on (with <a class="citerefentry" href="gluQuadricTexture.xml"><span class="citerefentry"><span class="refentrytitle">gluQuadricTexture</span></span></a>), 
            texture coordinates are generated
            linearly such that where 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mi mathvariant="italic">r</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mi mathvariant="italic">outer</mml:mi>
                </mml:mrow>
            </mml:math>,
            the value at (<span class="emphasis"><em>r</em></span>, 0, 0) is 
            (1, 0.5), at (0, <span class="emphasis"><em>r</em></span>, 0) it is (0.5, 1), at (\-<span class="emphasis"><em>r</em></span>, 0, 0) 
            it is (0, 0.5), and 
            at (0, \-<span class="emphasis"><em>r</em></span>, 0) it is (0.5, 0).
        </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="gluCylinder.xml"><span class="citerefentry"><span class="refentrytitle">gluCylinder</span></span></a>,
            <a class="citerefentry" href="gluNewQuadric.xml"><span class="citerefentry"><span class="refentrytitle">gluNewQuadric</span></span></a>,
            <a class="citerefentry" href="gluPartialDisk.xml"><span class="citerefentry"><span class="refentrytitle">gluPartialDisk</span></span></a>, 
            <a class="citerefentry" href="gluQuadricOrientation.xml"><span class="citerefentry"><span class="refentrytitle">gluQuadricOrientation</span></span></a>, 
            <a class="citerefentry" href="gluQuadricTexture.xml"><span class="citerefentry"><span class="refentrytitle">gluQuadricTexture</span></span></a>,
            <a class="citerefentry" href="gluSphere.xml"><span class="citerefentry"><span class="refentrytitle">gluSphere</span></span></a>
        </p></div><div class="refsect1"><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>