Opentk/Source/Bind/Specifications/Docs/gluPwlCurve.xml
2009-03-08 00:46:58 +00:00

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<?xml version="1.0" encoding="UTF-8"?>
<!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="gluPwlCurve">
<refmeta>
<refmetainfo>
<copyright>
<year>1991-2006</year>
<holder>Silicon Graphics, Inc.</holder>
</copyright>
</refmetainfo>
<refentrytitle>gluPwlCurve</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>gluPwlCurve</refname>
<refpurpose>describe a piecewise linear NURBS trimming curve</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>gluPwlCurve</function></funcdef>
<paramdef>GLUnurbs* <parameter>nurb</parameter></paramdef>
<paramdef>GLint <parameter>count</parameter></paramdef>
<paramdef>GLfloat* <parameter>data</parameter></paramdef>
<paramdef>GLint <parameter>stride</parameter></paramdef>
<paramdef>GLenum <parameter>type</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<!-- eqn: ignoring delim $$ -->
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>nurb</parameter></term>
<listitem>
<para>
Specifies the NURBS object (created with <citerefentry><refentrytitle>gluNewNurbsRenderer</refentrytitle></citerefentry>).
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>count</parameter></term>
<listitem>
<para>
Specifies the number of points on the curve.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>data</parameter></term>
<listitem>
<para>
Specifies an array containing the curve points.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>stride</parameter></term>
<listitem>
<para>
Specifies the offset (a number of single-precision floating-point values)
between points on the curve.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>type</parameter></term>
<listitem>
<para>
Specifies the type of curve.
Must be either <constant>GLU_MAP1_TRIM_2</constant> or <constant>GLU_MAP1_TRIM_3</constant>.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
<function>gluPwlCurve</function> 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.
</para>
<para>
If <parameter>type</parameter> is
<constant>GLU_MAP1_TRIM_2</constant>, then it describes a curve in two-dimensional (<emphasis>u</emphasis>
and <emphasis>v</emphasis>) parameter space. If it is <constant>GLU_MAP1_TRIM_3</constant>, then it
describes a curve in two-dimensional homogeneous (<emphasis>u</emphasis>, <emphasis>v</emphasis>,
and <emphasis>w</emphasis>) parameter space.
See the <citerefentry><refentrytitle>gluBeginTrim</refentrytitle></citerefentry> reference page for more information
about trimming curves.
</para>
</refsect1>
<refsect1 id="notes"><title>Notes</title>
<para>
To describe a trim curve that closely follows the contours of a NURBS
surface, call <citerefentry><refentrytitle>gluNurbsCurve</refentrytitle></citerefentry>.
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>gluBeginCurve</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>gluBeginTrim</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>gluNewNurbsRenderer</refentrytitle></citerefentry>,
<citerefentry><refentrytitle>gluNurbsCurve</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>