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1 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd"> |
2 | <!-- saved from url=(0013)about:internet --> | |
3 | <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glMap2</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glMap2"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glMap2 — define a two-dimensional evaluator</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glMap2f</b>(</code></td><td>GLenum </td><td><var class="pdparam">target</var>, </td></tr><tr><td> </td><td>GLfloat </td><td><var class="pdparam">u1</var>, </td></tr><tr><td> </td><td>GLfloat </td><td><var class="pdparam">u2</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">ustride</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">uorder</var>, </td></tr><tr><td> </td><td>GLfloat </td><td><var class="pdparam">v1</var>, </td></tr><tr><td> </td><td>GLfloat </td><td><var class="pdparam">v2</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">vstride</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">vorder</var>, </td></tr><tr><td> </td><td>const GLfloat * </td><td><var class="pdparam">points</var><code>)</code>;</td></tr></table></div><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glMap2d</b>(</code></td><td>GLenum </td><td><var class="pdparam">target</var>, </td></tr><tr><td> </td><td>GLdouble </td><td><var class="pdparam">u1</var>, </td></tr><tr><td> </td><td>GLdouble </td><td><var class="pdparam">u2</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">ustride</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">uorder</var>, </td></tr><tr><td> </td><td>GLdouble </td><td><var class="pdparam">v1</var>, </td></tr><tr><td> </td><td>GLdouble </td><td><var class="pdparam">v2</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">vstride</var>, </td></tr><tr><td> </td><td>GLint </td><td><var class="pdparam">vorder</var>, </td></tr><tr><td> </td><td>const GLdouble * </td><td><var class="pdparam">points</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>target</code></em></span></dt><dd><p> | |
4 | Specifies the kind of values that are generated by the evaluator. | |
5 | Symbolic constants | |
6 | <code class="constant">GL_MAP2_VERTEX_3</code>, | |
7 | <code class="constant">GL_MAP2_VERTEX_4</code>, | |
8 | <code class="constant">GL_MAP2_INDEX</code>, | |
9 | <code class="constant">GL_MAP2_COLOR_4</code>, | |
10 | <code class="constant">GL_MAP2_NORMAL</code>, | |
11 | <code class="constant">GL_MAP2_TEXTURE_COORD_1</code>, | |
12 | <code class="constant">GL_MAP2_TEXTURE_COORD_2</code>, | |
13 | <code class="constant">GL_MAP2_TEXTURE_COORD_3</code>, and | |
14 | <code class="constant">GL_MAP2_TEXTURE_COORD_4</code> are accepted. | |
15 | </p></dd><dt><span class="term"><em class="parameter"><code>u1</code></em>, </span><span class="term"><em class="parameter"><code>u2</code></em></span></dt><dd><p> | |
16 | Specify a linear mapping of | |
17 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">u</mml:mi></mml:math>, | |
18 | as presented to <a class="citerefentry" href="glEvalCoord2.xml"><span class="citerefentry"><span class="refentrytitle">glEvalCoord2</span></span></a>, | |
19 | to | |
20 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
21 | ||
22 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
23 | </mml:math>, | |
24 | one of the two variables that are evaluated by the equations specified | |
25 | by this command. Initially, <em class="parameter"><code>u1</code></em> is 0 and <em class="parameter"><code>u2</code></em> is 1. | |
26 | </p></dd><dt><span class="term"><em class="parameter"><code>ustride</code></em></span></dt><dd><p> | |
27 | Specifies the number of floats or doubles between | |
28 | the beginning of control point | |
29 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
30 | ||
31 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
32 | <mml:mi mathvariant="italic">ij</mml:mi> | |
33 | </mml:msub> | |
34 | </mml:math> | |
35 | and the beginning of control point | |
36 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
37 | ||
38 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
39 | <mml:mfenced open="" close=""> | |
40 | <mml:mrow> | |
41 | <mml:mfenced open="(" close=")"> | |
42 | <mml:mrow> | |
43 | <mml:mi mathvariant="italic">i</mml:mi> | |
44 | <mml:mo>+</mml:mo> | |
45 | <mml:mn>1</mml:mn> | |
46 | </mml:mrow> | |
47 | </mml:mfenced> | |
48 | <mml:mo></mml:mo> | |
49 | <mml:mi mathvariant="italic">j</mml:mi> | |
50 | </mml:mrow> | |
51 | </mml:mfenced> | |
52 | </mml:msub> | |
53 | </mml:math>, | |
54 | where | |
55 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">i</mml:mi></mml:math> | |
56 | and | |
57 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">j</mml:mi></mml:math> | |
58 | are the | |
59 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">u</mml:mi></mml:math> | |
60 | and | |
61 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">v</mml:mi></mml:math> | |
62 | control point indices, respectively. | |
63 | This allows control points to be embedded in arbitrary data structures. | |
64 | The only constraint is that the values for a particular control point | |
65 | must occupy contiguous memory locations. The initial value of <em class="parameter"><code>ustride</code></em> is 0. | |
66 | </p></dd><dt><span class="term"><em class="parameter"><code>uorder</code></em></span></dt><dd><p> | |
67 | Specifies the dimension of the control point array in the | |
68 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">u</mml:mi></mml:math> | |
69 | axis. | |
70 | Must be positive. The initial value is 1. | |
71 | </p></dd><dt><span class="term"><em class="parameter"><code>v1</code></em>, </span><span class="term"><em class="parameter"><code>v2</code></em></span></dt><dd><p> | |
72 | Specify a linear mapping of | |
73 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">v</mml:mi></mml:math>, | |
74 | as presented to <a class="citerefentry" href="glEvalCoord2.xml"><span class="citerefentry"><span class="refentrytitle">glEvalCoord2</span></span></a>, | |
75 | to | |
76 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
77 | ||
78 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
79 | </mml:math>, | |
80 | one of the two variables that are evaluated by the equations specified | |
81 | by this command. Initially, <em class="parameter"><code>v1</code></em> is 0 and <em class="parameter"><code>v2</code></em> is 1. | |
82 | </p></dd><dt><span class="term"><em class="parameter"><code>vstride</code></em></span></dt><dd><p> | |
83 | Specifies the number of floats or doubles between | |
84 | the beginning of control point | |
85 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
86 | ||
87 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
88 | <mml:mi mathvariant="italic">ij</mml:mi> | |
89 | </mml:msub> | |
90 | </mml:math> | |
91 | and the beginning of control point | |
92 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
93 | ||
94 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
95 | <mml:mfenced open="" close=""> | |
96 | <mml:mrow> | |
97 | <mml:mi mathvariant="italic">i</mml:mi> | |
98 | <mml:mo></mml:mo> | |
99 | <mml:mfenced open="(" close=")"> | |
100 | <mml:mrow> | |
101 | <mml:mi mathvariant="italic">j</mml:mi> | |
102 | <mml:mo>+</mml:mo> | |
103 | <mml:mn>1</mml:mn> | |
104 | </mml:mrow> | |
105 | </mml:mfenced> | |
106 | </mml:mrow> | |
107 | </mml:mfenced> | |
108 | </mml:msub> | |
109 | </mml:math>, | |
110 | where | |
111 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">i</mml:mi></mml:math> | |
112 | and | |
113 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">j</mml:mi></mml:math> | |
114 | are the | |
115 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">u</mml:mi></mml:math> | |
116 | and | |
117 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">v</mml:mi></mml:math> | |
118 | control point indices, respectively. | |
119 | This allows control points to be embedded in arbitrary data structures. | |
120 | The only constraint is that the values for a particular control point | |
121 | must occupy contiguous memory locations. The initial value of <em class="parameter"><code>vstride</code></em> is 0. | |
122 | </p></dd><dt><span class="term"><em class="parameter"><code>vorder</code></em></span></dt><dd><p> | |
123 | Specifies the dimension of the control point array in the | |
124 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">v</mml:mi></mml:math> | |
125 | axis. | |
126 | Must be positive. The initial value is 1. | |
127 | </p></dd><dt><span class="term"><em class="parameter"><code>points</code></em></span></dt><dd><p> | |
128 | Specifies a pointer to the array of control points. | |
129 | </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p> | |
130 | Evaluators provide a way to use polynomial or rational polynomial mapping | |
131 | to produce vertices, | |
132 | normals, | |
133 | texture coordinates, | |
134 | and colors. | |
135 | The values produced by an evaluator are sent on to further stages | |
136 | of GL processing just as if they had been presented using | |
137 | <a class="citerefentry" href="glVertex.xml"><span class="citerefentry"><span class="refentrytitle">glVertex</span></span></a>, | |
138 | <a class="citerefentry" href="glNormal.xml"><span class="citerefentry"><span class="refentrytitle">glNormal</span></span></a>, | |
139 | <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a>, and | |
140 | <a class="citerefentry" href="glColor.xml"><span class="citerefentry"><span class="refentrytitle">glColor</span></span></a> commands, | |
141 | except that the generated values do not update the current normal, | |
142 | texture coordinates, | |
143 | or color. | |
144 | </p><p> | |
145 | All polynomial or rational polynomial splines of any degree | |
146 | (up to the maximum degree supported by the GL implementation) | |
147 | can be described using evaluators. | |
148 | These include almost all surfaces used in computer graphics, | |
149 | including B-spline surfaces, | |
150 | NURBS surfaces, | |
151 | Bezier surfaces, and so on. | |
152 | </p><p> | |
153 | Evaluators define surfaces based on bivariate Bernstein polynomials. | |
154 | Define | |
155 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
156 | ||
157 | <mml:mrow> | |
158 | <mml:mi mathvariant="italic">p</mml:mi> | |
159 | <mml:mo></mml:mo> | |
160 | <mml:mfenced open="(" close=")"> | |
161 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
162 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
163 | </mml:mfenced> | |
164 | </mml:mrow> | |
165 | </mml:math> | |
166 | as | |
167 | </p><p> | |
168 | </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
169 | ||
170 | <mml:mrow> | |
171 | <mml:mrow> | |
172 | <mml:mi mathvariant="italic">p</mml:mi> | |
173 | <mml:mo></mml:mo> | |
174 | <mml:mfenced open="(" close=")"> | |
175 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
176 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
177 | </mml:mfenced> | |
178 | </mml:mrow> | |
179 | <mml:mo>=</mml:mo> | |
180 | <mml:mrow> | |
181 | <mml:munderover> | |
182 | <mml:mo>Σ</mml:mo> | |
183 | <mml:mrow> | |
184 | <mml:mi mathvariant="italic">i</mml:mi> | |
185 | <mml:mo>=</mml:mo> | |
186 | <mml:mn>0</mml:mn> | |
187 | </mml:mrow> | |
188 | <mml:mi mathvariant="italic">n</mml:mi> | |
189 | </mml:munderover> | |
190 | <mml:mrow> | |
191 | <mml:munderover> | |
192 | <mml:mo>Σ</mml:mo> | |
193 | <mml:mrow> | |
194 | <mml:mi mathvariant="italic">j</mml:mi> | |
195 | <mml:mo>=</mml:mo> | |
196 | <mml:mn>0</mml:mn> | |
197 | </mml:mrow> | |
198 | <mml:mi mathvariant="italic">m</mml:mi> | |
199 | </mml:munderover> | |
200 | <mml:mrow> | |
201 | <mml:mrow> | |
202 | <mml:msup><mml:mfenced open="" close=""> | |
203 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
204 | <mml:mi mathvariant="italic">i</mml:mi> | |
205 | </mml:msub> | |
206 | </mml:mfenced> | |
207 | <mml:mi mathvariant="italic">n</mml:mi> | |
208 | </mml:msup> | |
209 | <mml:mo></mml:mo> | |
210 | <mml:mfenced open="(" close=")"> | |
211 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
212 | </mml:mfenced> | |
213 | </mml:mrow> | |
214 | <mml:mo></mml:mo> | |
215 | <mml:mrow> | |
216 | <mml:msup><mml:mfenced open="" close=""> | |
217 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
218 | <mml:mi mathvariant="italic">j</mml:mi> | |
219 | </mml:msub> | |
220 | </mml:mfenced> | |
221 | <mml:mi mathvariant="italic">m</mml:mi> | |
222 | </mml:msup> | |
223 | <mml:mo></mml:mo> | |
224 | <mml:mfenced open="(" close=")"> | |
225 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
226 | </mml:mfenced> | |
227 | </mml:mrow> | |
228 | <mml:mo></mml:mo> | |
229 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
230 | <mml:mi mathvariant="italic">ij</mml:mi> | |
231 | </mml:msub> | |
232 | </mml:mrow> | |
233 | </mml:mrow> | |
234 | </mml:mrow> | |
235 | </mml:mrow> | |
236 | </mml:math></div><p> | |
237 | </p><p> | |
238 | </p><p> | |
239 | where | |
240 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
241 | ||
242 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
243 | <mml:mi mathvariant="italic">ij</mml:mi> | |
244 | </mml:msub> | |
245 | </mml:math> | |
246 | is a control point, | |
247 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
248 | ||
249 | <mml:mrow> | |
250 | <mml:msup><mml:mfenced open="" close=""> | |
251 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
252 | <mml:mi mathvariant="italic">i</mml:mi> | |
253 | </mml:msub> | |
254 | </mml:mfenced> | |
255 | <mml:mi mathvariant="italic">n</mml:mi> | |
256 | </mml:msup> | |
257 | <mml:mo></mml:mo> | |
258 | <mml:mfenced open="(" close=")"> | |
259 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
260 | </mml:mfenced> | |
261 | </mml:mrow> | |
262 | </mml:math> | |
263 | is the | |
264 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">i</mml:mi></mml:math>th | |
265 | Bernstein polynomial of degree | |
266 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">n</mml:mi></mml:math> | |
267 | (<em class="parameter"><code>uorder</code></em> = | |
268 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
269 | ||
270 | <mml:mrow> | |
271 | <mml:mi mathvariant="italic">n</mml:mi> | |
272 | <mml:mo>+</mml:mo> | |
273 | <mml:mn>1</mml:mn> | |
274 | </mml:mrow> | |
275 | </mml:math>) | |
276 | </p><p> | |
277 | </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
278 | ||
279 | <mml:mrow> | |
280 | <mml:mrow> | |
281 | <mml:msup><mml:mfenced open="" close=""> | |
282 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
283 | <mml:mi mathvariant="italic">i</mml:mi> | |
284 | </mml:msub> | |
285 | </mml:mfenced> | |
286 | <mml:mi mathvariant="italic">n</mml:mi> | |
287 | </mml:msup> | |
288 | <mml:mo></mml:mo> | |
289 | <mml:mfenced open="(" close=")"> | |
290 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
291 | </mml:mfenced> | |
292 | </mml:mrow> | |
293 | <mml:mo>=</mml:mo> | |
294 | <mml:mrow> | |
295 | <mml:mfenced open="(" close=")"> | |
296 | <mml:mfenced open="" close=""> | |
297 | <mml:mtable> | |
298 | <mml:mtr><mml:mtd> | |
299 | <mml:mi mathvariant="italic">n</mml:mi> | |
300 | </mml:mtd></mml:mtr> | |
301 | <mml:mtr><mml:mtd> | |
302 | <mml:mi mathvariant="italic">i</mml:mi> | |
303 | </mml:mtd></mml:mtr> | |
304 | </mml:mtable> | |
305 | </mml:mfenced> | |
306 | </mml:mfenced> | |
307 | <mml:mo></mml:mo> | |
308 | <mml:msup><mml:mfenced open="" close=""> | |
309 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
310 | </mml:mfenced> | |
311 | <mml:mi mathvariant="italic">i</mml:mi> | |
312 | </mml:msup> | |
313 | <mml:mo></mml:mo> | |
314 | <mml:mfenced open="" close=""> | |
315 | <mml:msup><mml:mfenced open="(" close=")"> | |
316 | <mml:mrow> | |
317 | <mml:mn>1</mml:mn> | |
318 | <mml:mo>-</mml:mo> | |
319 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
320 | </mml:mrow> | |
321 | </mml:mfenced> | |
322 | <mml:mfenced open="" close=""> | |
323 | <mml:mrow> | |
324 | <mml:mi mathvariant="italic">n</mml:mi> | |
325 | <mml:mo>-</mml:mo> | |
326 | <mml:mi mathvariant="italic">i</mml:mi> | |
327 | </mml:mrow> | |
328 | </mml:mfenced> | |
329 | </mml:msup> | |
330 | </mml:mfenced> | |
331 | </mml:mrow> | |
332 | </mml:mrow> | |
333 | </mml:math></div><p> | |
334 | </p><p> | |
335 | and | |
336 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
337 | ||
338 | <mml:mrow> | |
339 | <mml:msup><mml:mfenced open="" close=""> | |
340 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
341 | <mml:mi mathvariant="italic">j</mml:mi> | |
342 | </mml:msub> | |
343 | </mml:mfenced> | |
344 | <mml:mi mathvariant="italic">m</mml:mi> | |
345 | </mml:msup> | |
346 | <mml:mo></mml:mo> | |
347 | <mml:mfenced open="(" close=")"> | |
348 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
349 | </mml:mfenced> | |
350 | </mml:mrow> | |
351 | </mml:math> | |
352 | is the | |
353 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">j</mml:mi></mml:math>th | |
354 | Bernstein polynomial of degree | |
355 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">m</mml:mi></mml:math> | |
356 | (<em class="parameter"><code>vorder</code></em> = | |
357 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
358 | ||
359 | <mml:mrow> | |
360 | <mml:mi mathvariant="italic">m</mml:mi> | |
361 | <mml:mo>+</mml:mo> | |
362 | <mml:mn>1</mml:mn> | |
363 | </mml:mrow> | |
364 | </mml:math>) | |
365 | </p><p> | |
366 | </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
367 | ||
368 | <mml:mrow> | |
369 | <mml:mrow> | |
370 | <mml:msup><mml:mfenced open="" close=""> | |
371 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi> | |
372 | <mml:mi mathvariant="italic">j</mml:mi> | |
373 | </mml:msub> | |
374 | </mml:mfenced> | |
375 | <mml:mi mathvariant="italic">m</mml:mi> | |
376 | </mml:msup> | |
377 | <mml:mo></mml:mo> | |
378 | <mml:mfenced open="(" close=")"> | |
379 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
380 | </mml:mfenced> | |
381 | </mml:mrow> | |
382 | <mml:mo>=</mml:mo> | |
383 | <mml:mrow> | |
384 | <mml:mfenced open="(" close=")"> | |
385 | <mml:mfenced open="" close=""> | |
386 | <mml:mtable> | |
387 | <mml:mtr><mml:mtd> | |
388 | <mml:mi mathvariant="italic">m</mml:mi> | |
389 | </mml:mtd></mml:mtr> | |
390 | <mml:mtr><mml:mtd> | |
391 | <mml:mi mathvariant="italic">j</mml:mi> | |
392 | </mml:mtd></mml:mtr> | |
393 | </mml:mtable> | |
394 | </mml:mfenced> | |
395 | </mml:mfenced> | |
396 | <mml:mo></mml:mo> | |
397 | <mml:msup><mml:mfenced open="" close=""> | |
398 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
399 | </mml:mfenced> | |
400 | <mml:mi mathvariant="italic">j</mml:mi> | |
401 | </mml:msup> | |
402 | <mml:mo></mml:mo> | |
403 | <mml:mfenced open="" close=""> | |
404 | <mml:msup><mml:mfenced open="(" close=")"> | |
405 | <mml:mrow> | |
406 | <mml:mn>1</mml:mn> | |
407 | <mml:mo>-</mml:mo> | |
408 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
409 | </mml:mrow> | |
410 | </mml:mfenced> | |
411 | <mml:mfenced open="" close=""> | |
412 | <mml:mrow> | |
413 | <mml:mi mathvariant="italic">m</mml:mi> | |
414 | <mml:mo>-</mml:mo> | |
415 | <mml:mi mathvariant="italic">j</mml:mi> | |
416 | </mml:mrow> | |
417 | </mml:mfenced> | |
418 | </mml:msup> | |
419 | </mml:mfenced> | |
420 | </mml:mrow> | |
421 | </mml:mrow> | |
422 | </mml:math></div><p> | |
423 | </p><p> | |
424 | Recall that | |
425 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
426 | ||
427 | <mml:mrow> | |
428 | <mml:msup><mml:mn>0</mml:mn> | |
429 | <mml:mn>0</mml:mn> | |
430 | </mml:msup> | |
431 | <mml:mo>==</mml:mo> | |
432 | <mml:mn>1</mml:mn> | |
433 | </mml:mrow> | |
434 | </mml:math> | |
435 | and | |
436 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
437 | ||
438 | <mml:mrow> | |
439 | <mml:mfenced open="(" close=")"> | |
440 | <mml:mfenced open="" close=""> | |
441 | <mml:mtable> | |
442 | <mml:mtr><mml:mtd> | |
443 | <mml:mi mathvariant="italic">n</mml:mi> | |
444 | </mml:mtd></mml:mtr> | |
445 | <mml:mtr><mml:mtd> | |
446 | <mml:mn>0</mml:mn> | |
447 | </mml:mtd></mml:mtr> | |
448 | </mml:mtable> | |
449 | </mml:mfenced> | |
450 | </mml:mfenced> | |
451 | <mml:mo>==</mml:mo> | |
452 | <mml:mn>1</mml:mn> | |
453 | </mml:mrow> | |
454 | </mml:math> | |
455 | </p><p> | |
456 | <code class="function">glMap2</code> is used to define the basis and to specify what kind of values | |
457 | are produced. | |
458 | Once defined, | |
459 | a map can be enabled and disabled by calling <a class="citerefentry" href="glEnable.xml"><span class="citerefentry"><span class="refentrytitle">glEnable</span></span></a> and <a class="citerefentry" href="glDisable.xml"><span class="citerefentry"><span class="refentrytitle">glDisable</span></span></a> | |
460 | with the map name, one of the nine predefined values for <em class="parameter"><code>target</code></em>, | |
461 | described below. | |
462 | When <a class="citerefentry" href="glEvalCoord2.xml"><span class="citerefentry"><span class="refentrytitle">glEvalCoord2</span></span></a> presents values | |
463 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">u</mml:mi></mml:math> | |
464 | and | |
465 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">v</mml:mi></mml:math>, | |
466 | the bivariate Bernstein polynomials are evaluated using | |
467 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
468 | ||
469 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
470 | </mml:math> | |
471 | and | |
472 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
473 | ||
474 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
475 | </mml:math>, | |
476 | where | |
477 | </p><p> | |
478 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
479 | ||
480 | <mml:mrow> | |
481 | <mml:mover><mml:mi mathvariant="italic">u</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
482 | <mml:mo>=</mml:mo> | |
483 | <mml:mfrac> | |
484 | <mml:mfenced open="" close=""> | |
485 | <mml:mrow> | |
486 | <mml:mi mathvariant="italic">u</mml:mi> | |
487 | <mml:mo>-</mml:mo> | |
488 | <mml:mi mathvariant="italic">u1</mml:mi> | |
489 | </mml:mrow> | |
490 | </mml:mfenced> | |
491 | <mml:mfenced open="" close=""> | |
492 | <mml:mrow> | |
493 | <mml:mi mathvariant="italic">u2</mml:mi> | |
494 | <mml:mo>-</mml:mo> | |
495 | <mml:mi mathvariant="italic">u1</mml:mi> | |
496 | </mml:mrow> | |
497 | </mml:mfenced> | |
498 | </mml:mfrac> | |
499 | </mml:mrow> | |
500 | </mml:math> | |
501 | </p><p> | |
502 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
503 | ||
504 | <mml:mrow> | |
505 | <mml:mover><mml:mi mathvariant="italic">v</mml:mi><mml:mo>̂</mml:mo></mml:mover> | |
506 | <mml:mo>=</mml:mo> | |
507 | <mml:mfrac> | |
508 | <mml:mfenced open="" close=""> | |
509 | <mml:mrow> | |
510 | <mml:mi mathvariant="italic">v</mml:mi> | |
511 | <mml:mo>-</mml:mo> | |
512 | <mml:mi mathvariant="italic">v1</mml:mi> | |
513 | </mml:mrow> | |
514 | </mml:mfenced> | |
515 | <mml:mfenced open="" close=""> | |
516 | <mml:mrow> | |
517 | <mml:mi mathvariant="italic">v2</mml:mi> | |
518 | <mml:mo>-</mml:mo> | |
519 | <mml:mi mathvariant="italic">v1</mml:mi> | |
520 | </mml:mrow> | |
521 | </mml:mfenced> | |
522 | </mml:mfrac> | |
523 | </mml:mrow> | |
524 | </mml:math> | |
525 | </p><p> | |
526 | <em class="parameter"><code>target</code></em> is a symbolic constant that indicates what kind of control points | |
527 | are provided in <em class="parameter"><code>points</code></em>, | |
528 | and what output is generated when the map is evaluated. | |
529 | It can assume one of nine predefined values: | |
530 | </p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GL_MAP2_VERTEX_3</code></span></dt><dd><p> | |
531 | Each control point is three floating-point values representing | |
532 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>, | |
533 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>, | |
534 | and | |
535 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>. | |
536 | Internal <a class="citerefentry" href="glVertex3.xml"><span class="citerefentry"><span class="refentrytitle">glVertex3</span></span></a> commands are generated when the map is evaluated. | |
537 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_VERTEX_4</code></span></dt><dd><p> | |
538 | Each control point is four floating-point values representing | |
539 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>, | |
540 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>, | |
541 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math>, | |
542 | and | |
543 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">w</mml:mi></mml:math>. | |
544 | Internal <a class="citerefentry" href="glVertex4.xml"><span class="citerefentry"><span class="refentrytitle">glVertex4</span></span></a> commands are generated when the map is evaluated. | |
545 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_INDEX</code></span></dt><dd><p> | |
546 | Each control point is a single floating-point value representing a color index. | |
547 | Internal <a class="citerefentry" href="glIndex.xml"><span class="citerefentry"><span class="refentrytitle">glIndex</span></span></a> commands are generated when the map is evaluated | |
548 | but the current index is not updated with the value of these | |
549 | <a class="citerefentry" href="glIndex.xml"><span class="citerefentry"><span class="refentrytitle">glIndex</span></span></a> commands. | |
550 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_COLOR_4</code></span></dt><dd><p> | |
551 | Each control point is four floating-point values representing | |
552 | red, green, blue, and alpha. | |
553 | Internal <a class="citerefentry" href="glColor4.xml"><span class="citerefentry"><span class="refentrytitle">glColor4</span></span></a> commands are generated when the map is | |
554 | evaluated but the current color is not updated with the value of | |
555 | these <a class="citerefentry" href="glColor4.xml"><span class="citerefentry"><span class="refentrytitle">glColor4</span></span></a> commands. | |
556 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_NORMAL</code></span></dt><dd><p> | |
557 | Each control point is three floating-point values representing | |
558 | the | |
559 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">x</mml:mi></mml:math>, | |
560 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">y</mml:mi></mml:math>, | |
561 | and | |
562 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">z</mml:mi></mml:math> | |
563 | components of a normal vector. | |
564 | Internal <a class="citerefentry" href="glNormal.xml"><span class="citerefentry"><span class="refentrytitle">glNormal</span></span></a> commands are generated when the map is | |
565 | evaluated but the current normal is not updated with the value of | |
566 | these <a class="citerefentry" href="glNormal.xml"><span class="citerefentry"><span class="refentrytitle">glNormal</span></span></a> commands. | |
567 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_TEXTURE_COORD_1</code></span></dt><dd><p> | |
568 | Each control point is a single floating-point value representing | |
569 | the | |
570 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math> | |
571 | texture coordinate. | |
572 | Internal | |
573 | <a class="citerefentry" href="glTexCoord1.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord1</span></span></a> commands are generated when the map is evaluated but | |
574 | the current texture coordinates are not updated with the value | |
575 | of these <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a> commands. | |
576 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_TEXTURE_COORD_2</code></span></dt><dd><p> | |
577 | Each control point is two floating-point values representing | |
578 | the | |
579 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math> | |
580 | and | |
581 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">t</mml:mi></mml:math> | |
582 | texture coordinates. | |
583 | Internal | |
584 | <a class="citerefentry" href="glTexCoord2.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord2</span></span></a> commands are generated when the map is evaluated but | |
585 | the current texture coordinates are not updated with the value | |
586 | of these <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a> commands. | |
587 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_TEXTURE_COORD_3</code></span></dt><dd><p> | |
588 | Each control point is three floating-point values representing | |
589 | the | |
590 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math>, | |
591 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">t</mml:mi></mml:math>, | |
592 | and | |
593 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">r</mml:mi></mml:math> | |
594 | texture coordinates. | |
595 | Internal <a class="citerefentry" href="glTexCoord3.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord3</span></span></a> commands are generated when the map is | |
596 | evaluated but the current texture coordinates are not updated with the value | |
597 | of these <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a> commands. | |
598 | </p></dd><dt><span class="term"><code class="constant">GL_MAP2_TEXTURE_COORD_4</code></span></dt><dd><p> | |
599 | Each control point is four floating-point values representing | |
600 | the | |
601 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">s</mml:mi></mml:math>, | |
602 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">t</mml:mi></mml:math>, | |
603 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">r</mml:mi></mml:math>, | |
604 | and | |
605 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">q</mml:mi></mml:math> | |
606 | texture coordinates. | |
607 | Internal | |
608 | <a class="citerefentry" href="glTexCoord4.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord4</span></span></a> commands are generated when the map is evaluated but the current texture coordinates are not updated with the value | |
609 | of these <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a> commands. | |
610 | </p></dd></dl></div><p> | |
611 | <em class="parameter"><code>ustride</code></em>, | |
612 | <em class="parameter"><code>uorder</code></em>, | |
613 | <em class="parameter"><code>vstride</code></em>, | |
614 | <em class="parameter"><code>vorder</code></em>, and | |
615 | <em class="parameter"><code>points</code></em> define the array addressing for accessing the control points. | |
616 | <em class="parameter"><code>points</code></em> is the location of the first control point, | |
617 | which occupies one, two, three, or four contiguous memory locations, | |
618 | depending on which map is being defined. | |
619 | There are | |
620 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
621 | ||
622 | <mml:mrow> | |
623 | <mml:mi mathvariant="italic">uorder</mml:mi> | |
624 | <mml:mo>×</mml:mo> | |
625 | <mml:mi mathvariant="italic">vorder</mml:mi> | |
626 | </mml:mrow> | |
627 | </mml:math> | |
628 | control points in the array. | |
629 | <em class="parameter"><code>ustride</code></em> specifies how many float or double locations are skipped to advance | |
630 | the internal memory pointer from control point | |
631 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
632 | ||
633 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
634 | <mml:mfenced open="" close=""> | |
635 | <mml:mrow> | |
636 | <mml:mi mathvariant="italic">i</mml:mi> | |
637 | <mml:mo></mml:mo> | |
638 | <mml:mi mathvariant="italic">j</mml:mi> | |
639 | </mml:mrow> | |
640 | </mml:mfenced> | |
641 | </mml:msub> | |
642 | </mml:math> | |
643 | to control point | |
644 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
645 | ||
646 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
647 | <mml:mfenced open="" close=""> | |
648 | <mml:mrow> | |
649 | <mml:mfenced open="(" close=")"> | |
650 | <mml:mrow> | |
651 | <mml:mi mathvariant="italic">i</mml:mi> | |
652 | <mml:mo>+</mml:mo> | |
653 | <mml:mn>1</mml:mn> | |
654 | </mml:mrow> | |
655 | </mml:mfenced> | |
656 | <mml:mo></mml:mo> | |
657 | <mml:mi mathvariant="italic">j</mml:mi> | |
658 | </mml:mrow> | |
659 | </mml:mfenced> | |
660 | </mml:msub> | |
661 | </mml:math>. | |
662 | <em class="parameter"><code>vstride</code></em> specifies how many float or double locations are skipped to advance | |
663 | the internal memory pointer from control point | |
664 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
665 | ||
666 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
667 | <mml:mfenced open="" close=""> | |
668 | <mml:mrow> | |
669 | <mml:mi mathvariant="italic">i</mml:mi> | |
670 | <mml:mo></mml:mo> | |
671 | <mml:mi mathvariant="italic">j</mml:mi> | |
672 | </mml:mrow> | |
673 | </mml:mfenced> | |
674 | </mml:msub> | |
675 | </mml:math> | |
676 | to control point | |
677 | <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> | |
678 | ||
679 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi> | |
680 | <mml:mfenced open="" close=""> | |
681 | <mml:mrow> | |
682 | <mml:mi mathvariant="italic">i</mml:mi> | |
683 | <mml:mo></mml:mo> | |
684 | <mml:mfenced open="(" close=")"> | |
685 | <mml:mrow> | |
686 | <mml:mi mathvariant="italic">j</mml:mi> | |
687 | <mml:mo>+</mml:mo> | |
688 | <mml:mn>1</mml:mn> | |
689 | </mml:mrow> | |
690 | </mml:mfenced> | |
691 | </mml:mrow> | |
692 | </mml:mfenced> | |
693 | </mml:msub> | |
694 | </mml:math>. | |
695 | </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p> | |
696 | As is the case with all GL commands that accept pointers to data, | |
697 | it is as if the contents of <em class="parameter"><code>points</code></em> were copied by <code class="function">glMap2</code> before <code class="function">glMap2</code> | |
698 | returns. | |
699 | Changes to the contents of <em class="parameter"><code>points</code></em> have no effect after <code class="function">glMap2</code> is called. | |
700 | </p><p> | |
701 | Initially, <code class="constant">GL_AUTO_NORMAL</code> is enabled. If <code class="constant">GL_AUTO_NORMAL</code> is enabled, | |
702 | normal vectors are generated when either | |
703 | <code class="constant">GL_MAP2_VERTEX_3</code> or <code class="constant">GL_MAP2_VERTEX_4</code> is used to generate | |
704 | vertices. | |
705 | </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p> | |
706 | <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>target</code></em> is not an accepted value. | |
707 | </p><p> | |
708 | <code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>u1</code></em> is equal to <em class="parameter"><code>u2</code></em>, | |
709 | or if <em class="parameter"><code>v1</code></em> is equal to <em class="parameter"><code>v2</code></em>. | |
710 | </p><p> | |
711 | <code class="constant">GL_INVALID_VALUE</code> is generated if either <em class="parameter"><code>ustride</code></em> or <em class="parameter"><code>vstride</code></em> | |
712 | is less than the number of values in a control point. | |
713 | </p><p> | |
714 | <code class="constant">GL_INVALID_VALUE</code> is generated if either <em class="parameter"><code>uorder</code></em> or <em class="parameter"><code>vorder</code></em> | |
715 | is less than 1 or greater than the return value of <code class="constant">GL_MAX_EVAL_ORDER</code>. | |
716 | </p><p> | |
717 | <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glMap2</code> | |
718 | is executed between the execution of | |
719 | <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a> | |
720 | and the corresponding execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>. | |
721 | </p><p> | |
722 | <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glMap2</code> is called and the value | |
723 | of <code class="constant">GL_ACTIVE_TEXTURE</code> is not <code class="constant">GL_TEXTURE0</code>. | |
724 | </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p> | |
725 | <a class="citerefentry" href="glGetMap.xml"><span class="citerefentry"><span class="refentrytitle">glGetMap</span></span></a> | |
726 | </p><p> | |
727 | <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_EVAL_ORDER</code> | |
728 | </p><p> | |
729 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_VERTEX_3</code> | |
730 | </p><p> | |
731 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_VERTEX_4</code> | |
732 | </p><p> | |
733 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_INDEX</code> | |
734 | </p><p> | |
735 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_COLOR_4</code> | |
736 | </p><p> | |
737 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_NORMAL</code> | |
738 | </p><p> | |
739 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_TEXTURE_COORD_1</code> | |
740 | </p><p> | |
741 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_TEXTURE_COORD_2</code> | |
742 | </p><p> | |
743 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_TEXTURE_COORD_3</code> | |
744 | </p><p> | |
745 | <a class="citerefentry" href="glIsEnabled.xml"><span class="citerefentry"><span class="refentrytitle">glIsEnabled</span></span></a> with argument <code class="constant">GL_MAP2_TEXTURE_COORD_4</code> | |
746 | </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p> | |
747 | <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>, | |
748 | <a class="citerefentry" href="glColor.xml"><span class="citerefentry"><span class="refentrytitle">glColor</span></span></a>, | |
749 | <a class="citerefentry" href="glEnable.xml"><span class="citerefentry"><span class="refentrytitle">glEnable</span></span></a>, | |
750 | <a class="citerefentry" href="glEvalCoord.xml"><span class="citerefentry"><span class="refentrytitle">glEvalCoord</span></span></a>, | |
751 | <a class="citerefentry" href="glEvalMesh.xml"><span class="citerefentry"><span class="refentrytitle">glEvalMesh</span></span></a>, | |
752 | <a class="citerefentry" href="glEvalPoint.xml"><span class="citerefentry"><span class="refentrytitle">glEvalPoint</span></span></a>, | |
753 | <a class="citerefentry" href="glMap1.xml"><span class="citerefentry"><span class="refentrytitle">glMap1</span></span></a>, | |
754 | <a class="citerefentry" href="glMapGrid.xml"><span class="citerefentry"><span class="refentrytitle">glMapGrid</span></span></a>, | |
755 | <a class="citerefentry" href="glNormal.xml"><span class="citerefentry"><span class="refentrytitle">glNormal</span></span></a>, | |
756 | <a class="citerefentry" href="glTexCoord.xml"><span class="citerefentry"><span class="refentrytitle">glTexCoord</span></span></a>, | |
757 | <a class="citerefentry" href="glVertex.xml"><span class="citerefentry"><span class="refentrytitle">glVertex</span></span></a> | |
758 | </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p> | |
759 | Copyright <span class="trademark"></span>© 1991-2006 | |
760 | Silicon Graphics, Inc. This document is licensed under the SGI | |
761 | Free Software B License. For details, see | |
762 | <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>. | |
763 | </p></div></div></body></html> |