mirror of
https://github.com/Ryujinx/Opentk.git
synced 2024-12-26 09:35:36 +00:00
621 lines
32 KiB
XML
621 lines
32 KiB
XML
|
<?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="glMap1">
|
||
|
<refmeta>
|
||
|
<refmetainfo>
|
||
|
<copyright>
|
||
|
<year>1991-2006</year>
|
||
|
<holder>Silicon Graphics, Inc.</holder>
|
||
|
</copyright>
|
||
|
</refmetainfo>
|
||
|
<refentrytitle>glMap1</refentrytitle>
|
||
|
<manvolnum>3G</manvolnum>
|
||
|
</refmeta>
|
||
|
<refnamediv>
|
||
|
<refname>glMap1</refname>
|
||
|
<refpurpose>define a one-dimensional evaluator</refpurpose>
|
||
|
</refnamediv>
|
||
|
<refsynopsisdiv><title>C Specification</title>
|
||
|
<funcsynopsis>
|
||
|
<funcprototype>
|
||
|
<funcdef>void <function>glMap1f</function></funcdef>
|
||
|
<paramdef>GLenum <parameter>target</parameter></paramdef>
|
||
|
<paramdef>GLfloat <parameter>u1</parameter></paramdef>
|
||
|
<paramdef>GLfloat <parameter>u2</parameter></paramdef>
|
||
|
<paramdef>GLint <parameter>stride</parameter></paramdef>
|
||
|
<paramdef>GLint <parameter>order</parameter></paramdef>
|
||
|
<paramdef>const GLfloat * <parameter>points</parameter></paramdef>
|
||
|
</funcprototype>
|
||
|
</funcsynopsis>
|
||
|
<funcsynopsis>
|
||
|
<funcprototype>
|
||
|
<funcdef>void <function>glMap1d</function></funcdef>
|
||
|
<paramdef>GLenum <parameter>target</parameter></paramdef>
|
||
|
<paramdef>GLdouble <parameter>u1</parameter></paramdef>
|
||
|
<paramdef>GLdouble <parameter>u2</parameter></paramdef>
|
||
|
<paramdef>GLint <parameter>stride</parameter></paramdef>
|
||
|
<paramdef>GLint <parameter>order</parameter></paramdef>
|
||
|
<paramdef>const GLdouble * <parameter>points</parameter></paramdef>
|
||
|
</funcprototype>
|
||
|
</funcsynopsis>
|
||
|
</refsynopsisdiv>
|
||
|
<!-- eqn: ignoring delim $$ -->
|
||
|
<refsect1 id="parameters"><title>Parameters</title>
|
||
|
<variablelist>
|
||
|
<varlistentry>
|
||
|
<term><parameter>target</parameter></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Specifies the kind of values that are generated by the evaluator.
|
||
|
Symbolic constants
|
||
|
<constant>GL_MAP1_VERTEX_3</constant>,
|
||
|
<constant>GL_MAP1_VERTEX_4</constant>,
|
||
|
<constant>GL_MAP1_INDEX</constant>,
|
||
|
<constant>GL_MAP1_COLOR_4</constant>,
|
||
|
<constant>GL_MAP1_NORMAL</constant>,
|
||
|
<constant>GL_MAP1_TEXTURE_COORD_1</constant>,
|
||
|
<constant>GL_MAP1_TEXTURE_COORD_2</constant>,
|
||
|
<constant>GL_MAP1_TEXTURE_COORD_3</constant>, and
|
||
|
<constant>GL_MAP1_TEXTURE_COORD_4</constant> are accepted.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><parameter>u1</parameter></term>
|
||
|
<term><parameter>u2</parameter></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Specify a linear mapping of
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">u</mml:mi></mml:math></inlineequation>,
|
||
|
as presented to <citerefentry><refentrytitle>glEvalCoord1</refentrytitle></citerefentry>,
|
||
|
to
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: u hat:-->
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:math></inlineequation>,
|
||
|
the variable that is evaluated by the equations specified by this command.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><parameter>stride</parameter></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Specifies the number of floats or doubles between
|
||
|
the beginning of one control point and the beginning of the next one
|
||
|
in the data structure referenced in <parameter>points</parameter>.
|
||
|
This allows control points to be embedded in arbitrary data structures.
|
||
|
The only constraint is that the values for a particular control point
|
||
|
must occupy contiguous memory locations.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><parameter>order</parameter></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Specifies the number of control points.
|
||
|
Must be positive.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><parameter>points</parameter></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Specifies a pointer to the array of control points.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
</variablelist>
|
||
|
</refsect1>
|
||
|
<refsect1 id="description"><title>Description</title>
|
||
|
<para>
|
||
|
Evaluators provide a way to use polynomial or rational polynomial mapping
|
||
|
to produce vertices,
|
||
|
normals,
|
||
|
texture coordinates,
|
||
|
and colors.
|
||
|
The values produced by an evaluator are sent to further stages
|
||
|
of GL processing just as if they had been presented using
|
||
|
<citerefentry><refentrytitle>glVertex</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry>, and
|
||
|
<citerefentry><refentrytitle>glColor</refentrytitle></citerefentry> commands,
|
||
|
except that the generated values do not update the current normal,
|
||
|
texture coordinates,
|
||
|
or color.
|
||
|
</para>
|
||
|
<para>
|
||
|
All polynomial or rational polynomial splines of any degree
|
||
|
(up to the maximum degree supported by the GL implementation)
|
||
|
can be described using evaluators.
|
||
|
These include almost all splines used in computer graphics: B-splines,
|
||
|
Bezier curves, Hermite splines, and so on.
|
||
|
</para>
|
||
|
<para>
|
||
|
Evaluators define curves based on Bernstein polynomials.
|
||
|
Define
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: p ( u hat):-->
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">p</mml:mi>
|
||
|
<mml:mo>⁡</mml:mo>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
as
|
||
|
</para>
|
||
|
<para>
|
||
|
<informalequation><mml:math>
|
||
|
<!-- eqn: p ( u hat) = sum from {i = 0} to {n} { {B sub i} sup n ( u hat ) R sub i }:-->
|
||
|
<mml:mrow>
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">p</mml:mi>
|
||
|
<mml:mo>⁡</mml:mo>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
<mml:mo>=</mml:mo>
|
||
|
<mml:mrow>
|
||
|
<mml:munderover>
|
||
|
<mml:mo>Σ</mml:mo>
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
<mml:mo>=</mml:mo>
|
||
|
<mml:mn>0</mml:mn>
|
||
|
</mml:mrow>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:munderover>
|
||
|
<mml:mrow>
|
||
|
<mml:mrow>
|
||
|
<mml:msup><mml:mfenced open="" close="">
|
||
|
<mml:msub><mml:mi mathvariant="italic">B</mml:mi>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msub>
|
||
|
</mml:mfenced>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:msup>
|
||
|
<mml:mo>⁡</mml:mo>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
<mml:mo>⁢</mml:mo>
|
||
|
<mml:msub><mml:mi mathvariant="italic">R</mml:mi>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msub>
|
||
|
</mml:mrow>
|
||
|
</mml:mrow>
|
||
|
</mml:mrow>
|
||
|
</mml:math></informalequation>
|
||
|
</para>
|
||
|
<para>
|
||
|
</para>
|
||
|
<para>
|
||
|
where
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: R sub i:-->
|
||
|
<mml:msub><mml:mi mathvariant="italic">R</mml:mi>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msub>
|
||
|
</mml:math></inlineequation>
|
||
|
is a control point and
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: {B sub i} sup n ( u hat):-->
|
||
|
<mml:mrow>
|
||
|
<mml:msup><mml:mfenced open="" close="">
|
||
|
<mml:msub><mml:mi mathvariant="italic">B</mml:mi>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msub>
|
||
|
</mml:mfenced>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:msup>
|
||
|
<mml:mo>⁡</mml:mo>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
is the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
|
||
|
Bernstein polynomial of degree
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">n</mml:mi></mml:math></inlineequation>
|
||
|
(<parameter>order</parameter> =
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: n + 1:-->
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
<mml:mo>+</mml:mo>
|
||
|
<mml:mn>1</mml:mn>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>):
|
||
|
</para>
|
||
|
<para>
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: {B sub i} sup n ( u hat) = left ( {cpile { n above i }} right ) {u hat} sup i { ( 1 - u hat) sup { n - i } }:-->
|
||
|
<mml:mrow>
|
||
|
<mml:mrow>
|
||
|
<mml:msup><mml:mfenced open="" close="">
|
||
|
<mml:msub><mml:mi mathvariant="italic">B</mml:mi>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msub>
|
||
|
</mml:mfenced>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:msup>
|
||
|
<mml:mo>⁡</mml:mo>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
<mml:mo>=</mml:mo>
|
||
|
<mml:mrow>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:mtable>
|
||
|
<mml:mtr><mml:mtd>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:mtd></mml:mtr>
|
||
|
<mml:mtr><mml:mtd>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:mtd></mml:mtr>
|
||
|
</mml:mtable>
|
||
|
</mml:mfenced>
|
||
|
</mml:mfenced>
|
||
|
<mml:mo>⁢</mml:mo>
|
||
|
<mml:msup><mml:mfenced open="" close="">
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mfenced>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:msup>
|
||
|
<mml:mo>⁢</mml:mo>
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:msup><mml:mfenced open="(" close=")">
|
||
|
<mml:mrow>
|
||
|
<mml:mn>1</mml:mn>
|
||
|
<mml:mo>-</mml:mo>
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:mrow>
|
||
|
</mml:mfenced>
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
<mml:mo>-</mml:mo>
|
||
|
<mml:mi mathvariant="italic">i</mml:mi>
|
||
|
</mml:mrow>
|
||
|
</mml:mfenced>
|
||
|
</mml:msup>
|
||
|
</mml:mfenced>
|
||
|
</mml:mrow>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
</para>
|
||
|
<para>
|
||
|
Recall that
|
||
|
</para>
|
||
|
<para>
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: 0 sup 0 == 1:-->
|
||
|
<mml:mrow>
|
||
|
<mml:msup><mml:mn>0</mml:mn>
|
||
|
<mml:mn>0</mml:mn>
|
||
|
</mml:msup>
|
||
|
<mml:mo>==</mml:mo>
|
||
|
<mml:mn>1</mml:mn>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
and
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: left ( {cpile { n above 0 }} right ) == 1:-->
|
||
|
<mml:mrow>
|
||
|
<mml:mfenced open="(" close=")">
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:mtable>
|
||
|
<mml:mtr><mml:mtd>
|
||
|
<mml:mi mathvariant="italic">n</mml:mi>
|
||
|
</mml:mtd></mml:mtr>
|
||
|
<mml:mtr><mml:mtd>
|
||
|
<mml:mn>0</mml:mn>
|
||
|
</mml:mtd></mml:mtr>
|
||
|
</mml:mtable>
|
||
|
</mml:mfenced>
|
||
|
</mml:mfenced>
|
||
|
<mml:mo>==</mml:mo>
|
||
|
<mml:mn>1</mml:mn>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
</para>
|
||
|
<para>
|
||
|
<function>glMap1</function> is used to define the basis and to specify what kind of values
|
||
|
are produced.
|
||
|
Once defined,
|
||
|
a map can be enabled and disabled by calling <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry>
|
||
|
with the map name, one of the nine predefined values for <parameter>target</parameter>
|
||
|
described below.
|
||
|
<citerefentry><refentrytitle>glEvalCoord1</refentrytitle></citerefentry> evaluates the one-dimensional maps that are enabled.
|
||
|
When
|
||
|
<citerefentry><refentrytitle>glEvalCoord1</refentrytitle></citerefentry> presents a value
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">u</mml:mi></mml:math></inlineequation>,
|
||
|
the Bernstein functions are evaluated using
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: u hat:-->
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
</mml:math></inlineequation>,
|
||
|
where
|
||
|
<inlineequation><mml:math>
|
||
|
<!-- eqn: u hat = {u - u1} over {u2 - u1}:-->
|
||
|
<mml:mrow>
|
||
|
<mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>^</mml:mo></mml:mover>
|
||
|
<mml:mo>=</mml:mo>
|
||
|
<mml:mfrac>
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">u</mml:mi>
|
||
|
<mml:mo>-</mml:mo>
|
||
|
<mml:mi mathvariant="italic">u1</mml:mi>
|
||
|
</mml:mrow>
|
||
|
</mml:mfenced>
|
||
|
<mml:mfenced open="" close="">
|
||
|
<mml:mrow>
|
||
|
<mml:mi mathvariant="italic">u2</mml:mi>
|
||
|
<mml:mo>-</mml:mo>
|
||
|
<mml:mi mathvariant="italic">u1</mml:mi>
|
||
|
</mml:mrow>
|
||
|
</mml:mfenced>
|
||
|
</mml:mfrac>
|
||
|
</mml:mrow>
|
||
|
</mml:math></inlineequation>
|
||
|
</para>
|
||
|
<para>
|
||
|
<parameter>target</parameter> is a symbolic constant that indicates what kind of control points
|
||
|
are provided in <parameter>points</parameter>,
|
||
|
and what output is generated when the map is evaluated.
|
||
|
It can assume one of nine predefined values:
|
||
|
</para>
|
||
|
<variablelist>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_VERTEX_3</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is three floating-point values representing
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">x</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">y</mml:mi></mml:math></inlineequation>,
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">z</mml:mi></mml:math></inlineequation>.
|
||
|
Internal <citerefentry><refentrytitle>glVertex3</refentrytitle></citerefentry> commands are generated when the map is evaluated.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_VERTEX_4</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is four floating-point values representing
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">x</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">y</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">z</mml:mi></mml:math></inlineequation>,
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">w</mml:mi></mml:math></inlineequation>.
|
||
|
Internal <citerefentry><refentrytitle>glVertex4</refentrytitle></citerefentry> commands are generated when the map is evaluated.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_INDEX</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is a single floating-point value representing a color index.
|
||
|
Internal <citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry> commands are generated when the map is evaluated
|
||
|
but the current index is not updated with the value of these <citerefentry><refentrytitle>glIndex</refentrytitle></citerefentry>
|
||
|
commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_COLOR_4</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is four floating-point values representing
|
||
|
red, green, blue, and alpha.
|
||
|
Internal <citerefentry><refentrytitle>glColor4</refentrytitle></citerefentry> commands are generated when the map is
|
||
|
evaluated but the current color is not updated with the value of these
|
||
|
<citerefentry><refentrytitle>glColor4</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_NORMAL</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is three floating-point values representing
|
||
|
the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">x</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">y</mml:mi></mml:math></inlineequation>,
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">z</mml:mi></mml:math></inlineequation>
|
||
|
components of a normal vector.
|
||
|
Internal <citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry> commands are generated when the map is
|
||
|
evaluated but the current normal is not updated with the value of
|
||
|
these <citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_TEXTURE_COORD_1</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is a single floating-point value representing
|
||
|
the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
||
|
texture coordinate.
|
||
|
Internal
|
||
|
<citerefentry><refentrytitle>glTexCoord1</refentrytitle></citerefentry> commands are generated when the map is
|
||
|
evaluated but the current texture coordinates are not updated with the value
|
||
|
of these <citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_TEXTURE_COORD_2</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is two floating-point values representing
|
||
|
the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>
|
||
|
texture coordinates.
|
||
|
Internal
|
||
|
<citerefentry><refentrytitle>glTexCoord2</refentrytitle></citerefentry> commands are generated when the map is
|
||
|
evaluated but the current texture coordinates are not updated with the value
|
||
|
of these <citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_TEXTURE_COORD_3</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is three floating-point values representing
|
||
|
the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>,
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">r</mml:mi></mml:math></inlineequation>
|
||
|
texture coordinates.
|
||
|
Internal <citerefentry><refentrytitle>glTexCoord3</refentrytitle></citerefentry> commands are generated when the map is
|
||
|
evaluated but the current texture coordinates are not updated with the value
|
||
|
of these <citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
<varlistentry>
|
||
|
<term><constant>GL_MAP1_TEXTURE_COORD_4</constant></term>
|
||
|
<listitem>
|
||
|
<para>
|
||
|
Each control point is four floating-point values representing
|
||
|
the
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">s</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">t</mml:mi></mml:math></inlineequation>,
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">r</mml:mi></mml:math></inlineequation>,
|
||
|
and
|
||
|
<inlineequation><mml:math><mml:mi mathvariant="italic">q</mml:mi></mml:math></inlineequation>
|
||
|
texture coordinates.
|
||
|
Internal
|
||
|
<citerefentry><refentrytitle>glTexCoord4</refentrytitle></citerefentry> commands are generated when the map is evaluated but
|
||
|
the current texture coordinates are not updated with the value
|
||
|
of these <citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry> commands.
|
||
|
</para>
|
||
|
</listitem>
|
||
|
</varlistentry>
|
||
|
</variablelist>
|
||
|
<para>
|
||
|
<parameter>stride</parameter>,
|
||
|
<parameter>order</parameter>, and
|
||
|
<parameter>points</parameter> define the array addressing for accessing the control points.
|
||
|
<parameter>points</parameter> is the location of the first control point,
|
||
|
which occupies one, two, three, or four contiguous memory locations,
|
||
|
depending on which map is being defined.
|
||
|
<parameter>order</parameter> is the number of control points in the array.
|
||
|
<parameter>stride</parameter> specifies how many float or double locations to advance the internal
|
||
|
memory pointer to reach the next control point.
|
||
|
</para>
|
||
|
</refsect1>
|
||
|
<refsect1 id="notes"><title>Notes</title>
|
||
|
<para>
|
||
|
As is the case with all GL commands that accept pointers to data,
|
||
|
it is as if the contents of <parameter>points</parameter> were copied by <function>glMap1</function> before <function>glMap1</function>
|
||
|
returns.
|
||
|
Changes to the contents of <parameter>points</parameter> have no effect after <function>glMap1</function> is called.
|
||
|
</para>
|
||
|
</refsect1>
|
||
|
<refsect1 id="errors"><title>Errors</title>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not an accepted value.
|
||
|
</para>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>u1</parameter> is equal to <parameter>u2</parameter>.
|
||
|
</para>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>stride</parameter> is less than the number
|
||
|
of values in a control point.
|
||
|
</para>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_VALUE</constant> is generated if <parameter>order</parameter> is less than 1 or
|
||
|
greater than the return value of <constant>GL_MAX_EVAL_ORDER</constant>.
|
||
|
</para>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glMap1</function>
|
||
|
is executed between the execution of
|
||
|
<citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
|
||
|
and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
||
|
</para>
|
||
|
<para>
|
||
|
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glMap1</function> is called and the value
|
||
|
of <constant>GL_ACTIVE_TEXTURE</constant> is not <constant>GL_TEXTURE0</constant>.
|
||
|
</para>
|
||
|
</refsect1>
|
||
|
<refsect1 id="associatedgets"><title>Associated Gets</title>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glGetMap</refentrytitle></citerefentry>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_EVAL_ORDER</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_VERTEX_3</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_VERTEX_4</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_INDEX</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_COLOR_4</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_NORMAL</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_TEXTURE_COORD_1</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_TEXTURE_COORD_2</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_TEXTURE_COORD_3</constant>
|
||
|
</para>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_MAP1_TEXTURE_COORD_4</constant>
|
||
|
</para>
|
||
|
</refsect1>
|
||
|
<refsect1 id="seealso"><title>See Also</title>
|
||
|
<para>
|
||
|
<citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glColor</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glEvalCoord</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glEvalMesh</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glEvalPoint</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glMap2</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glMapGrid</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glNormal</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glTexCoord</refentrytitle></citerefentry>,
|
||
|
<citerefentry><refentrytitle>glVertex</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>
|