upstream-man-pages/man2/gluSphere.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
   3               "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
   4 <refentry id="gluSphere">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>gluSphere</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>gluSphere</refname>
  17         <refpurpose>draw a sphere</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>gluSphere</function></funcdef>
  23                 <paramdef>GLUquadric* <parameter>quad</parameter></paramdef>
  24                 <paramdef>GLdouble <parameter>radius</parameter></paramdef>
  25                 <paramdef>GLint <parameter>slices</parameter></paramdef>
  26                 <paramdef>GLint <parameter>stacks</parameter></paramdef>
  27             </funcprototype>
  28         </funcsynopsis>
  29     </refsynopsisdiv>
  30     <!-- eqn: ignoring delim $$ -->
  31     <refsect1 id="parameters"><title>Parameters</title>
  32         <variablelist>
  33         <varlistentry>
  34             <term><parameter>quad</parameter></term>
  35             <listitem>
  36                 <para>
  37                     Specifies the quadrics object (created with <citerefentry><refentrytitle>gluNewQuadric</refentrytitle></citerefentry>).
  38                 </para>
  39             </listitem>
  40         </varlistentry>
  41         <varlistentry>
  42             <term><parameter>radius</parameter></term>
  43             <listitem>
  44                 <para>
  45                     Specifies the radius of the sphere.
  46                 </para>
  47             </listitem>
  48         </varlistentry>
  49         <varlistentry>
  50             <term><parameter>slices</parameter></term>
  51             <listitem>
  52                 <para>
  53                     Specifies the number of subdivisions around the <emphasis>z</emphasis> axis
  54                     (similar to lines of longitude).
  55                 </para>
  56             </listitem>
  57         </varlistentry>
  58         <varlistentry>
  59             <term><parameter>stacks</parameter></term>
  60             <listitem>
  61                 <para>
  62                     Specifies the number of subdivisions along the <emphasis>z</emphasis> axis
  63                     (similar to lines of
  64                     latitude).
  65                 </para>
  66             </listitem>
  67         </varlistentry>
  68         </variablelist>
  69     </refsect1>
  70     <refsect1 id="description"><title>Description</title>
  71         <para>
  72             <function>gluSphere</function> draws a sphere of the given radius centered around the origin. The
  73             sphere is subdivided around the <emphasis>z</emphasis> axis into slices and along the
  74             <emphasis>z</emphasis> axis
  75             into stacks (similar to lines of longitude and latitude).
  76         </para>
  77         <para>
  78             If the orientation is set to <constant>GLU_OUTSIDE</constant>
  79             (with <citerefentry><refentrytitle>gluQuadricOrientation</refentrytitle></citerefentry>), then any normals generated
  80             point away from the center of the sphere.
  81             Otherwise, they point toward the center of the sphere.
  82         </para>
  83         <para>
  84             If texturing is turned on (with <citerefentry><refentrytitle>gluQuadricTexture</refentrytitle></citerefentry>), then texture
  85             coordinates are
  86             generated so that <emphasis>t</emphasis> ranges from 0.0 at
  87             <inlineequation><mml:math>
  88                 <!-- eqn: z  =  -radius:-->
  89                 <mml:mrow>
  90                     <mml:mi mathvariant="italic">z</mml:mi>
  91                     <mml:mo>=</mml:mo>
  92                     <mml:mrow>
  93                         <mml:mo>-</mml:mo>
  94                         <mml:mi mathvariant="italic">radius</mml:mi>
  95                     </mml:mrow>
  96                 </mml:mrow>
  97             </mml:math></inlineequation>
  98             to 1.0 at
  99             <inlineequation><mml:math>
 100                 <!-- eqn: z  =  radius:-->
 101                 <mml:mrow>
 102                     <mml:mi mathvariant="italic">z</mml:mi>
 103                     <mml:mo>=</mml:mo>
 104                     <mml:mi mathvariant="italic">radius</mml:mi>
 105                 </mml:mrow>
 106             </mml:math></inlineequation>
 107             (<emphasis>t</emphasis> increases linearly along longitudinal
 108             lines),
 109             and <emphasis>s</emphasis> ranges from 0.0 at the +<emphasis>y</emphasis> axis, to 0.25 at the
 110             +<emphasis>x</emphasis> axis,
 111             to 0.5 at the \-<emphasis>y</emphasis> axis, to 0.75 at the \-<emphasis>x</emphasis> axis, and back to 1.0
 112             at the +<emphasis>y</emphasis> axis.
 113         </para>
 114     </refsect1>
 115     <refsect1 id="seealso"><title>See Also</title>
 116         <para>
 117             <citerefentry><refentrytitle>gluCylinder</refentrytitle></citerefentry>,
 118             <citerefentry><refentrytitle>gluDisk</refentrytitle></citerefentry>,
 119             <citerefentry><refentrytitle>gluNewQuadric</refentrytitle></citerefentry>,
 120             <citerefentry><refentrytitle>gluPartialDisk</refentrytitle></citerefentry>,
 121             <citerefentry><refentrytitle>gluQuadricOrientation</refentrytitle></citerefentry>,
 122             <citerefentry><refentrytitle>gluQuadricTexture</refentrytitle></citerefentry>
 123         </para>
 124     </refsect1>
 125     <refsect1 id="Copyright"><title>Copyright</title>
 126         <para>
 127             Copyright <trademark class="copyright"></trademark> 1991-2006
 128             Silicon Graphics, Inc. This document is licensed under the SGI
 129             Free Software B License. For details, see
 130             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
 131         </para>
 132     </refsect1>
 133 </refentry>