mirror of
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620 lines
32 KiB
XML
620 lines
32 KiB
XML
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<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
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"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
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<refentry id="glBegin">
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<refmeta>
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<refmetainfo>
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<copyright>
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<year>1991-2006</year>
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<holder>Silicon Graphics, Inc.</holder>
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</copyright>
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</refmetainfo>
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<refentrytitle>glBegin</refentrytitle>
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<manvolnum>3G</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>glBegin</refname>
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<refpurpose>delimit the vertices of a primitive or a group of like primitives</refpurpose>
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</refnamediv>
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<refsynopsisdiv><title>C Specification</title>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glBegin</function></funcdef>
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<paramdef>GLenum <parameter>mode</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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<!-- eqn: ignoring delim $$ -->
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<refsect1 id="parameters"><title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><parameter>mode</parameter></term>
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<listitem>
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<para>
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Specifies the primitive or primitives that will be created from vertices
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presented between <function>glBegin</function> and the subsequent <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
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Ten symbolic constants are accepted:
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<constant>GL_POINTS</constant>,
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<constant>GL_LINES</constant>,
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<constant>GL_LINE_STRIP</constant>,
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<constant>GL_LINE_LOOP</constant>,
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<constant>GL_TRIANGLES</constant>,
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<constant>GL_TRIANGLE_STRIP</constant>,
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<constant>GL_TRIANGLE_FAN</constant>,
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<constant>GL_QUADS</constant>,
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<constant>GL_QUAD_STRIP</constant>, and
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<constant>GL_POLYGON</constant>.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsynopsisdiv><title>C Specification</title>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glEnd</function></funcdef>
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<paramdef><parameter>void</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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<refsect1 id="description"><title>Description</title>
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<para>
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<function>glBegin</function> and <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry> delimit the vertices that define a primitive or
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a group of like primitives.
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<function>glBegin</function> accepts a single argument that specifies in which of ten ways the
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vertices are interpreted.
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Taking
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
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as an integer count starting at one,
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and
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<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
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as the total number of vertices specified,
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the interpretations are as follows:
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</para>
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<variablelist>
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<varlistentry>
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<term><constant>GL_POINTS</constant></term>
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<listitem>
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<para>
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Treats each vertex as a single point.
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Vertex
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
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defines point
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
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points are drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINES</constant></term>
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<listitem>
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<para>
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Treats each pair of vertices as an independent line segment.
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Vertices
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<inlineequation><mml:math>
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<!-- eqn: 2n - 1:-->
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<mml:mrow>
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<mml:mn>2</mml:mn>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>-</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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and
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<inlineequation><mml:math>
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<!-- eqn: 2n:-->
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<mml:mrow>
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<mml:mn>2</mml:mn>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">n</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>
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define line
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math>
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<!-- eqn: N/2:-->
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<mml:mfrac>
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<mml:mi mathvariant="italic">N</mml:mi>
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<mml:mn>2</mml:mn>
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</mml:mfrac>
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</mml:math></inlineequation>
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lines are drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINE_STRIP</constant></term>
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<listitem>
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<para>
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Draws a connected group of line segments from the first vertex
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to the last.
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Vertices
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
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and
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<inlineequation><mml:math>
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<!-- eqn: n + 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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define line
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math>
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<!-- eqn: N - 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">N</mml:mi>
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<mml:mo>-</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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lines are drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_LINE_LOOP</constant></term>
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<listitem>
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<para>
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Draws a connected group of line segments from the first vertex
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to the last,
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then back to the first.
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Vertices
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
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and
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<inlineequation><mml:math>
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<!-- eqn: n + 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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define line
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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The last line, however, is defined by vertices
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<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
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and
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<inlineequation><mml:math>
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<!-- eqn: 1:-->
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<mml:mn>1</mml:mn>
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</mml:math></inlineequation>.
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<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
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lines are drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_TRIANGLES</constant></term>
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<listitem>
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<para>
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Treats each triplet of vertices as an independent triangle.
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Vertices
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<inlineequation><mml:math>
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<!-- eqn: 3n - 2:-->
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<mml:mrow>
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<mml:mn>3</mml:mn>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>-</mml:mo>
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<mml:mn>2</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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<inlineequation><mml:math>
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<!-- eqn: 3n - 1:-->
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<mml:mrow>
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<mml:mn>3</mml:mn>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>-</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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and
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<inlineequation><mml:math>
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<!-- eqn: 3n:-->
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<mml:mrow>
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<mml:mn>3</mml:mn>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">n</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>
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define triangle
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math>
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<!-- eqn: N/3:-->
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<mml:mfrac>
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<mml:mi mathvariant="italic">N</mml:mi>
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<mml:mn>3</mml:mn>
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</mml:mfrac>
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</mml:math></inlineequation>
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triangles are drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_TRIANGLE_STRIP</constant></term>
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<listitem>
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<para>
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Draws a connected group of triangles. One triangle is defined for each
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vertex presented after the first two vertices. For odd
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>,
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vertices
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>,
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<inlineequation><mml:math>
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<!-- eqn: n + 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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and
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<inlineequation><mml:math>
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<!-- eqn: n + 2:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>2</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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define triangle
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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For even
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>,
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vertices
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<inlineequation><mml:math>
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<!-- eqn: n + 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>,
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and
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<inlineequation><mml:math>
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<!-- eqn: n + 2:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>2</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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define triangle
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math>
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<!-- eqn: N - 2:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">N</mml:mi>
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<mml:mo>-</mml:mo>
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<mml:mn>2</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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triangles are
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drawn.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_TRIANGLE_FAN</constant></term>
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<listitem>
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<para>
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Draws a connected group of triangles.
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One triangle is defined for each vertex presented after the first two vertices.
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Vertices
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<inlineequation><mml:math>
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<!-- eqn: 1:-->
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<mml:mn>1</mml:mn>
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</mml:math></inlineequation>,
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<inlineequation><mml:math>
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<!-- eqn: n + 1:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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and
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<inlineequation><mml:math>
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<!-- eqn: n + 2:-->
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<mml:mrow>
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<mml:mi mathvariant="italic">n</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mn>2</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>
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define triangle
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<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
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<inlineequation><mml:math>
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<!-- eqn: N - 2:-->
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<mml:mrow>
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|
|
<mml:mi mathvariant="italic">N</mml:mi>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
triangles are drawn.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</varlistentry>
|
||
|
|
<varlistentry>
|
||
|
|
<term><constant>GL_QUADS</constant></term>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Treats each group of four vertices as an independent quadrilateral.
|
||
|
|
Vertices
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 4n - 3:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>4</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>3</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 4n - 2:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>4</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 4n - 1:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>4</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>1</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
and
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 4n:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>4</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
define quadrilateral
|
||
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: N/4:-->
|
||
|
|
<mml:mfrac>
|
||
|
|
<mml:mi mathvariant="italic">N</mml:mi>
|
||
|
|
<mml:mn>4</mml:mn>
|
||
|
|
</mml:mfrac>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
quadrilaterals are drawn.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</varlistentry>
|
||
|
|
<varlistentry>
|
||
|
|
<term><constant>GL_QUAD_STRIP</constant></term>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Draws a connected group of quadrilaterals.
|
||
|
|
One quadrilateral is defined for each pair of vertices presented
|
||
|
|
after the first pair.
|
||
|
|
Vertices
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 2n - 1:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>1</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 2n:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 2n + 2:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>+</mml:mo>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>,
|
||
|
|
and
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 2n + 1:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
<mml:mo>⁢</mml:mo>
|
||
|
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
|
<mml:mo>+</mml:mo>
|
||
|
|
<mml:mn>1</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
define quadrilateral
|
||
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>.
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: N/2 - 1:-->
|
||
|
|
<mml:mrow>
|
||
|
|
<mml:mfrac>
|
||
|
|
<mml:mi mathvariant="italic">N</mml:mi>
|
||
|
|
<mml:mn>2</mml:mn>
|
||
|
|
</mml:mfrac>
|
||
|
|
<mml:mo>-</mml:mo>
|
||
|
|
<mml:mn>1</mml:mn>
|
||
|
|
</mml:mrow>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
quadrilaterals are drawn.
|
||
|
|
Note that the order in which vertices are used to construct a quadrilateral
|
||
|
|
from strip data is different from that used with independent data.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</varlistentry>
|
||
|
|
<varlistentry>
|
||
|
|
<term><constant>GL_POLYGON</constant></term>
|
||
|
|
<listitem>
|
||
|
|
<para>
|
||
|
|
Draws a single,
|
||
|
|
convex polygon.
|
||
|
|
Vertices
|
||
|
|
<inlineequation><mml:math>
|
||
|
|
<!-- eqn: 1:-->
|
||
|
|
<mml:mn>1</mml:mn>
|
||
|
|
</mml:math></inlineequation>
|
||
|
|
through
|
||
|
|
<inlineequation><mml:math><mml:mi mathvariant="italic">N</mml:mi></mml:math></inlineequation>
|
||
|
|
define this polygon.
|
||
|
|
</para>
|
||
|
|
</listitem>
|
||
|
|
</varlistentry>
|
||
|
|
</variablelist>
|
||
|
|
<para>
|
||
|
|
Only a subset of GL commands can be used between <function>glBegin</function> and <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
||
|
|
The commands are
|
||
|
|
<citerefentry><refentrytitle>glVertex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glSecondaryColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glFogCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMultiTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertexAttrib</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalPoint</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMaterial</refentrytitle></citerefentry>, and
|
||
|
|
<citerefentry><refentrytitle>glEdgeFlag</refentrytitle></citerefentry>.
|
||
|
|
Also,
|
||
|
|
it is acceptable to use
|
||
|
|
<citerefentry><refentrytitle>glCallList</refentrytitle></citerefentry> or
|
||
|
|
<citerefentry><refentrytitle>glCallLists</refentrytitle></citerefentry> to execute
|
||
|
|
display lists that include only the preceding commands.
|
||
|
|
If any other GL command is executed between <function>glBegin</function> and <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>,
|
||
|
|
the error flag is set and the command is ignored.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
Regardless of the value chosen for <parameter>mode</parameter>,
|
||
|
|
there is no limit to the number of vertices that can be defined
|
||
|
|
between <function>glBegin</function> and <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
||
|
|
Lines,
|
||
|
|
triangles,
|
||
|
|
quadrilaterals,
|
||
|
|
and polygons that are incompletely specified are not drawn.
|
||
|
|
Incomplete specification results when either too few vertices are
|
||
|
|
provided to specify even a single primitive or when an incorrect multiple
|
||
|
|
of vertices is specified. The incomplete primitive is ignored; the rest are drawn.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
The minimum specification of vertices
|
||
|
|
for each primitive is as follows:
|
||
|
|
1 for a point,
|
||
|
|
2 for a line,
|
||
|
|
3 for a triangle,
|
||
|
|
4 for a quadrilateral,
|
||
|
|
and 3 for a polygon.
|
||
|
|
Modes that require a certain multiple of vertices are
|
||
|
|
<constant>GL_LINES</constant> (2),
|
||
|
|
<constant>GL_TRIANGLES</constant> (3),
|
||
|
|
<constant>GL_QUADS</constant> (4),
|
||
|
|
and <constant>GL_QUAD_STRIP</constant> (2).
|
||
|
|
</para>
|
||
|
|
</refsect1>
|
||
|
|
<refsect1 id="errors"><title>Errors</title>
|
||
|
|
<para>
|
||
|
|
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>mode</parameter> is set to an unaccepted value.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glBegin</function> is executed between a
|
||
|
|
<function>glBegin</function>
|
||
|
|
and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry> is executed without being
|
||
|
|
preceded by a <function>glBegin</function>.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if a command other than
|
||
|
|
<citerefentry><refentrytitle>glVertex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glSecondaryColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glFogCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMultiTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertexAttrib</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalPoint</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMaterial</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEdgeFlag</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glCallList</refentrytitle></citerefentry>, or
|
||
|
|
<citerefentry><refentrytitle>glCallLists</refentrytitle></citerefentry> is executed between
|
||
|
|
the execution of <function>glBegin</function> and the corresponding
|
||
|
|
execution <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
||
|
|
</para>
|
||
|
|
<para>
|
||
|
|
Execution of
|
||
|
|
<citerefentry><refentrytitle>glEnableClientState</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glDisableClientState</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEdgeFlagPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glFogCoordPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glTexCoordPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glColorPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glSecondaryColorPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glIndexPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glNormalPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertexPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertexAttribPointer</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glInterleavedArrays</refentrytitle></citerefentry>, or
|
||
|
|
<citerefentry><refentrytitle>glPixelStore</refentrytitle></citerefentry> is not allowed after a call to <function>glBegin</function> and before
|
||
|
|
the corresponding call to <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>,
|
||
|
|
but an error may or may not be generated.
|
||
|
|
</para>
|
||
|
|
</refsect1>
|
||
|
|
<refsect1 id="seealso"><title>See Also</title>
|
||
|
|
<para>
|
||
|
|
<citerefentry><refentrytitle>glArrayElement</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glCallList</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glCallLists</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEdgeFlag</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glEvalPoint</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glFogCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMaterial</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glMultiTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glSecondaryColor</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertex</refentrytitle></citerefentry>,
|
||
|
|
<citerefentry><refentrytitle>glVertexAttrib</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>
|