1 /*
2 * Copyright (c) 1993-1997, Silicon Graphics, Inc.
3 * ALL RIGHTS RESERVED
4 * Permission to use, copy, modify, and distribute this software for
5 * any purpose and without fee is hereby granted, provided that the above
6 * copyright notice appear in all copies and that both the copyright notice
7 * and this permission notice appear in supporting documentation, and that
8 * the name of Silicon Graphics, Inc. not be used in advertising
9 * or publicity pertaining to distribution of the software without specific,
10 * written prior permission.
11 *
12 * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
13 * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
14 * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
15 * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
16 * GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
17 * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
18 * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
19 * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
20 * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN
21 * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
22 * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
23 * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
24 *
25 * US Government Users Restricted Rights
26 * Use, duplication, or disclosure by the Government is subject to
27 * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
28 * (c)(1)(ii) of the Rights in Technical Data and Computer Software
29 * clause at DFARS 252.227-7013 and/or in similar or successor
30 * clauses in the FAR or the DOD or NASA FAR Supplement.
31 * Unpublished-- rights reserved under the copyright laws of the
32 * United States. Contractor/manufacturer is Silicon Graphics,
33 * Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.
34 *
35 * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.
36 */
37
38 /*
39 * tesswind.c
40 * This program demonstrates the winding rule polygon
41 * tessellation property. Four tessellated objects are drawn,
42 * each with very different contours. When the w key is pressed,
43 * the objects are drawn with a different winding rule.
44 */
45 #include "glut_wrap.h"
46 #include <stdlib.h>
47 #include <stdio.h>
48
49 #ifdef GLU_VERSION_1_2
50
51 GLdouble currentWinding = GLU_TESS_WINDING_ODD;
52 int currentShape = 0;
53 GLUtesselator *tobj;
54 GLuint list;
55
56 /* Make four display lists,
57 * each with a different tessellated object.
58 */
makeNewLists(void)59 static void makeNewLists (void) {
60 int i;
61 static GLdouble rects[12][3] =
62 {{ 50.0, 50.0, 0.0}, {300.0, 50.0, 0.0},
63 {300.0, 300.0, 0.0}, { 50.0, 300.0, 0.0},
64 {100.0, 100.0, 0.0}, {250.0, 100.0, 0.0},
65 {250.0, 250.0, 0.0}, {100.0, 250.0, 0.0},
66 {150.0, 150.0, 0.0}, {200.0, 150.0, 0.0},
67 {200.0, 200.0, 0.0}, {150.0, 200.0, 0.0}};
68 static GLdouble spiral[16][3] =
69 {{400.0, 250.0, 0.0}, {400.0, 50.0, 0.0},
70 { 50.0, 50.0, 0.0}, { 50.0, 400.0, 0.0},
71 {350.0, 400.0, 0.0}, {350.0, 100.0, 0.0},
72 {100.0, 100.0, 0.0}, {100.0, 350.0, 0.0},
73 {300.0, 350.0, 0.0}, {300.0, 150.0, 0.0},
74 {150.0, 150.0, 0.0}, {150.0, 300.0, 0.0},
75 {250.0, 300.0, 0.0}, {250.0, 200.0, 0.0},
76 {200.0, 200.0, 0.0}, {200.0, 250.0, 0.0}};
77 static GLdouble quad1[4][3] =
78 {{ 50.0, 150.0, 0.0}, {350.0, 150.0, 0.0},
79 {350.0, 200.0, 0.0}, { 50.0, 200.0, 0.0}};
80 static GLdouble quad2[4][3] =
81 {{100.0, 100.0, 0.0}, {300.0, 100.0, 0.0},
82 {300.0, 350.0, 0.0}, {100.0, 350.0, 0.0}};
83 static GLdouble tri[3][3] =
84 {{200.0, 50.0, 0.0}, {250.0, 300.0, 0.0},
85 {150.0, 300.0, 0.0}};
86
87 gluTessProperty(tobj, GLU_TESS_WINDING_RULE,
88 currentWinding);
89
90 glNewList(list, GL_COMPILE);
91 gluTessBeginPolygon(tobj, NULL);
92 gluTessBeginContour(tobj);
93 for (i = 0; i < 4; i++)
94 gluTessVertex(tobj, rects[i], rects[i]);
95 gluTessEndContour(tobj);
96 gluTessBeginContour(tobj);
97 for (i = 4; i < 8; i++)
98 gluTessVertex(tobj, rects[i], rects[i]);
99 gluTessEndContour(tobj);
100 gluTessBeginContour(tobj);
101 for (i = 8; i < 12; i++)
102 gluTessVertex(tobj, rects[i], rects[i]);
103 gluTessEndContour(tobj);
104 gluTessEndPolygon(tobj);
105 glEndList();
106
107 glNewList(list+1, GL_COMPILE);
108 gluTessBeginPolygon(tobj, NULL);
109 gluTessBeginContour(tobj);
110 for (i = 0; i < 4; i++)
111 gluTessVertex(tobj, rects[i], rects[i]);
112 gluTessEndContour(tobj);
113 gluTessBeginContour(tobj);
114 for (i = 7; i >= 4; i--)
115 gluTessVertex(tobj, rects[i], rects[i]);
116 gluTessEndContour(tobj);
117 gluTessBeginContour(tobj);
118 for (i = 11; i >= 8; i--)
119 gluTessVertex(tobj, rects[i], rects[i]);
120 gluTessEndContour(tobj);
121 gluTessEndPolygon(tobj);
122 glEndList();
123
124 glNewList(list+2, GL_COMPILE);
125 gluTessBeginPolygon(tobj, NULL);
126 gluTessBeginContour(tobj);
127 for (i = 0; i < 16; i++)
128 gluTessVertex(tobj, spiral[i], spiral[i]);
129 gluTessEndContour(tobj);
130 gluTessEndPolygon(tobj);
131 glEndList();
132
133 glNewList(list+3, GL_COMPILE);
134 gluTessBeginPolygon(tobj, NULL);
135 gluTessBeginContour(tobj);
136 for (i = 0; i < 4; i++)
137 gluTessVertex(tobj, quad1[i], quad1[i]);
138 gluTessEndContour(tobj);
139 gluTessBeginContour(tobj);
140 for (i = 0; i < 4; i++)
141 gluTessVertex(tobj, quad2[i], quad2[i]);
142 gluTessEndContour(tobj);
143 gluTessBeginContour(tobj);
144 for (i = 0; i < 3; i++)
145 gluTessVertex(tobj, tri[i], tri[i]);
146 gluTessEndContour(tobj);
147 gluTessEndPolygon(tobj);
148 glEndList();
149 }
150
display(void)151 static void display (void) {
152 glClear(GL_COLOR_BUFFER_BIT);
153 glColor3f(1.0, 1.0, 1.0);
154 glPushMatrix();
155 glCallList(list);
156 glTranslatef(0.0, 500.0, 0.0);
157 glCallList(list+1);
158 glTranslatef(500.0, -500.0, 0.0);
159 glCallList(list+2);
160 glTranslatef(0.0, 500.0, 0.0);
161 glCallList(list+3);
162 glPopMatrix();
163 glFlush();
164 }
165
beginCallback(GLenum which)166 static void GLAPIENTRY beginCallback(GLenum which)
167 {
168 glBegin(which);
169 }
170
errorCallback(GLenum errorCode)171 static void GLAPIENTRY errorCallback(GLenum errorCode)
172 {
173 const GLubyte *estring;
174
175 estring = gluErrorString(errorCode);
176 fprintf(stderr, "Tessellation Error: %s\n", (char *) estring);
177 exit(0);
178 }
179
endCallback(void)180 static void GLAPIENTRY endCallback(void)
181 {
182 glEnd();
183 }
184
185 /* combineCallback is used to create a new vertex when edges
186 * intersect. coordinate location is trivial to calculate,
187 * but weight[4] may be used to average color, normal, or texture
188 * coordinate data.
189 */
190 /* ARGSUSED */
combineCallback(GLdouble coords[3],GLdouble * data[4],GLfloat weight[4],GLdouble ** dataOut)191 static void GLAPIENTRY combineCallback(GLdouble coords[3], GLdouble *data[4],
192 GLfloat weight[4], GLdouble **dataOut )
193 {
194 GLdouble *vertex;
195 vertex = (GLdouble *) malloc(3 * sizeof(GLdouble));
196
197 vertex[0] = coords[0];
198 vertex[1] = coords[1];
199 vertex[2] = coords[2];
200 *dataOut = vertex;
201 }
202
init(void)203 static void init(void)
204 {
205 glClearColor(0.0, 0.0, 0.0, 0.0);
206 glShadeModel(GL_FLAT);
207
208 tobj = gluNewTess();
209 gluTessCallback(tobj, GLU_TESS_VERTEX, &glVertex3dv);
210 gluTessCallback(tobj, GLU_TESS_BEGIN, &beginCallback);
211 gluTessCallback(tobj, GLU_TESS_END, &endCallback);
212 gluTessCallback(tobj, GLU_TESS_ERROR, &errorCallback);
213 gluTessCallback(tobj, GLU_TESS_COMBINE, &combineCallback);
214
215 list = glGenLists(4);
216 makeNewLists();
217 }
218
reshape(int w,int h)219 static void reshape(int w, int h)
220 {
221 glViewport(0, 0, (GLsizei) w, (GLsizei) h);
222 glMatrixMode(GL_PROJECTION);
223 glLoadIdentity();
224 if (w <= h)
225 gluOrtho2D(0.0, 1000.0, 0.0, 1000.0 * (GLdouble)h/(GLdouble)w);
226 else
227 gluOrtho2D(0.0, 1000.0 * (GLdouble)w/(GLdouble)h, 0.0, 1000.0);
228 glMatrixMode(GL_MODELVIEW);
229 glLoadIdentity();
230 }
231
232 /* ARGSUSED1 */
keyboard(unsigned char key,int x,int y)233 static void keyboard(unsigned char key, int x, int y)
234 {
235 switch (key) {
236 case 'w':
237 case 'W':
238 if (currentWinding == GLU_TESS_WINDING_ODD)
239 currentWinding = GLU_TESS_WINDING_NONZERO;
240 else if (currentWinding == GLU_TESS_WINDING_NONZERO)
241 currentWinding = GLU_TESS_WINDING_POSITIVE;
242 else if (currentWinding == GLU_TESS_WINDING_POSITIVE)
243 currentWinding = GLU_TESS_WINDING_NEGATIVE;
244 else if (currentWinding == GLU_TESS_WINDING_NEGATIVE)
245 currentWinding = GLU_TESS_WINDING_ABS_GEQ_TWO;
246 else if (currentWinding == GLU_TESS_WINDING_ABS_GEQ_TWO)
247 currentWinding = GLU_TESS_WINDING_ODD;
248 makeNewLists();
249 glutPostRedisplay();
250 break;
251 case 27:
252 exit(0);
253 break;
254 default:
255 break;
256 }
257 }
258
main(int argc,char ** argv)259 int main(int argc, char** argv)
260 {
261 glutInit(&argc, argv);
262 glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
263 glutInitWindowSize(500, 500);
264 glutCreateWindow(argv[0]);
265 init();
266 glutDisplayFunc(display);
267 glutReshapeFunc(reshape);
268 glutKeyboardFunc(keyboard);
269 glutMainLoop();
270 return 0;
271 }
272
273 #else
main(int argc,char ** argv)274 int main(int argc, char** argv)
275 {
276 fprintf (stderr, "This program demonstrates the new tesselator API in GLU 1.2.\n");
277 fprintf (stderr, "Your GLU library does not support this new interface, sorry.\n");
278 return 0;
279 }
280 #endif
281