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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
              "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
<refentry id="gluSphere">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>gluSphere</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>gluSphere</refname>
        <refpurpose>draw a sphere</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>gluSphere</function></funcdef>
                <paramdef>GLUquadric* <parameter>quad</parameter></paramdef>
                <paramdef>GLdouble <parameter>radius</parameter></paramdef>
                <paramdef>GLint <parameter>slices</parameter></paramdef>
                <paramdef>GLint <parameter>stacks</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <!-- eqn: ignoring delim $$ -->
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>quad</parameter></term>
            <listitem>
                <para>
                    Specifies the quadrics object (created with <citerefentry><refentrytitle>gluNewQuadric</refentrytitle></citerefentry>).
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>radius</parameter></term>
            <listitem>
                <para>
                    Specifies the radius of the sphere.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>slices</parameter></term>
            <listitem>
                <para>
                    Specifies the number of subdivisions around the <emphasis>z</emphasis> axis 
                    (similar to lines of longitude).
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>stacks</parameter></term>
            <listitem>
                <para>
                    Specifies the number of subdivisions along the <emphasis>z</emphasis> axis
                    (similar to lines of
                    latitude).
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            <function>gluSphere</function> draws a sphere of the given radius centered around the origin. The
            sphere is subdivided around the <emphasis>z</emphasis> axis into slices and along the 
            <emphasis>z</emphasis> axis 
            into stacks (similar to lines of longitude and latitude).
        </para>
        <para>
            If the orientation is set to <constant>GLU_OUTSIDE</constant> 
            (with <citerefentry><refentrytitle>gluQuadricOrientation</refentrytitle></citerefentry>), then any normals generated 
            point away from the center of the sphere.
            Otherwise, they point toward the center of the sphere.
        </para>
        <para>
            If texturing is turned on (with <citerefentry><refentrytitle>gluQuadricTexture</refentrytitle></citerefentry>), then texture 
            coordinates are 
            generated so that <emphasis>t</emphasis> ranges from 0.0 at 
            <inlineequation><mml:math>
                <!-- eqn: z  =  -radius:-->
                <mml:mrow>
                    <mml:mi mathvariant="italic">z</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mrow>
                        <mml:mo>-</mml:mo>
                        <mml:mi mathvariant="italic">radius</mml:mi>
                    </mml:mrow>
                </mml:mrow>
            </mml:math></inlineequation>
            to 1.0 at 
            <inlineequation><mml:math>
                <!-- eqn: z  =  radius:-->
                <mml:mrow>
                    <mml:mi mathvariant="italic">z</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mi mathvariant="italic">radius</mml:mi>
                </mml:mrow>
            </mml:math></inlineequation>
            (<emphasis>t</emphasis> increases linearly along longitudinal
            lines),
            and <emphasis>s</emphasis> ranges from 0.0 at the +<emphasis>y</emphasis> axis, to 0.25 at the 
            +<emphasis>x</emphasis> axis, 
            to 0.5 at the \-<emphasis>y</emphasis> axis, to 0.75 at the \-<emphasis>x</emphasis> axis, and back to 1.0 
            at the +<emphasis>y</emphasis> axis.
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>gluCylinder</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluDisk</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluNewQuadric</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluPartialDisk</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluQuadricOrientation</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>gluQuadricTexture</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>
