progs/redbook/tesswind.c

   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  31  * Unpublished-- rights reserved under the copyright laws of the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 <GL/glut.h>
  46 #include <stdlib.h>
  47 #include <stdio.h>
  48
  49 #ifdef GLU_VERSION_1_2
  50
  51 /* Win32 calling conventions. */
  52 #ifndef CALLBACK
  53 #define CALLBACK
  54 #endif
  55
  56 GLdouble currentWinding = GLU_TESS_WINDING_ODD;
  57 int currentShape = 0;
  58 GLUtesselator *tobj;
  59 GLuint list;
  60
  61 /*  Make four display lists,
  62  *  each with a different tessellated object.
  63  */
  64 static void makeNewLists (void) {
  65    int i;
  66    static GLdouble rects[12][3] =
  67       {{ 50.0,  50.0, 0.0}, {300.0,  50.0, 0.0},
  68        {300.0, 300.0, 0.0}, { 50.0, 300.0, 0.0},
  69        {100.0, 100.0, 0.0}, {250.0, 100.0, 0.0},
  70        {250.0, 250.0, 0.0}, {100.0, 250.0, 0.0},
  71        {150.0, 150.0, 0.0}, {200.0, 150.0, 0.0},
  72        {200.0, 200.0, 0.0}, {150.0, 200.0, 0.0}};
  73    static GLdouble spiral[16][3] =
  74       {{400.0, 250.0, 0.0}, {400.0,  50.0, 0.0},
  75        { 50.0,  50.0, 0.0}, { 50.0, 400.0, 0.0},
  76        {350.0, 400.0, 0.0}, {350.0, 100.0, 0.0},
  77        {100.0, 100.0, 0.0}, {100.0, 350.0, 0.0},
  78        {300.0, 350.0, 0.0}, {300.0, 150.0, 0.0},
  79        {150.0, 150.0, 0.0}, {150.0, 300.0, 0.0},
  80        {250.0, 300.0, 0.0}, {250.0, 200.0, 0.0},
  81        {200.0, 200.0, 0.0}, {200.0, 250.0, 0.0}};
  82    static GLdouble quad1[4][3] =
  83       {{ 50.0, 150.0, 0.0}, {350.0, 150.0, 0.0},
  84        {350.0, 200.0, 0.0}, { 50.0, 200.0, 0.0}};
  85    static GLdouble quad2[4][3] =
  86       {{100.0, 100.0, 0.0}, {300.0, 100.0, 0.0},
  87        {300.0, 350.0, 0.0}, {100.0, 350.0, 0.0}};
  88    static GLdouble tri[3][3] =
  89       {{200.0, 50.0, 0.0}, {250.0, 300.0, 0.0},
  90        {150.0, 300.0, 0.0}};
  91
  92    gluTessProperty(tobj, GLU_TESS_WINDING_RULE,
  93                    currentWinding);
  94
  95    glNewList(list, GL_COMPILE);
  96       gluTessBeginPolygon(tobj, NULL);
  97          gluTessBeginContour(tobj);
  98          for (i = 0; i < 4; i++)
  99             gluTessVertex(tobj, rects[i], rects[i]);
 100          gluTessEndContour(tobj);
 101          gluTessBeginContour(tobj);
 102          for (i = 4; i < 8; i++)
 103             gluTessVertex(tobj, rects[i], rects[i]);
 104          gluTessEndContour(tobj);
 105          gluTessBeginContour(tobj);
 106          for (i = 8; i < 12; i++)
 107             gluTessVertex(tobj, rects[i], rects[i]);
 108          gluTessEndContour(tobj);
 109       gluTessEndPolygon(tobj);
 110    glEndList();
 111
 112    glNewList(list+1, GL_COMPILE);
 113       gluTessBeginPolygon(tobj, NULL);
 114          gluTessBeginContour(tobj);
 115          for (i = 0; i < 4; i++)
 116             gluTessVertex(tobj, rects[i], rects[i]);
 117          gluTessEndContour(tobj);
 118          gluTessBeginContour(tobj);
 119          for (i = 7; i >= 4; i--)
 120             gluTessVertex(tobj, rects[i], rects[i]);
 121          gluTessEndContour(tobj);
 122          gluTessBeginContour(tobj);
 123          for (i = 11; i >= 8; i--)
 124             gluTessVertex(tobj, rects[i], rects[i]);
 125          gluTessEndContour(tobj);
 126       gluTessEndPolygon(tobj);
 127    glEndList();
 128
 129    glNewList(list+2, GL_COMPILE);
 130       gluTessBeginPolygon(tobj, NULL);
 131          gluTessBeginContour(tobj);
 132          for (i = 0; i < 16; i++)
 133             gluTessVertex(tobj, spiral[i], spiral[i]);
 134          gluTessEndContour(tobj);
 135       gluTessEndPolygon(tobj);
 136    glEndList();
 137
 138    glNewList(list+3, GL_COMPILE);
 139       gluTessBeginPolygon(tobj, NULL);
 140          gluTessBeginContour(tobj);
 141          for (i = 0; i < 4; i++)
 142             gluTessVertex(tobj, quad1[i], quad1[i]);
 143          gluTessEndContour(tobj);
 144          gluTessBeginContour(tobj);
 145          for (i = 0; i < 4; i++)
 146             gluTessVertex(tobj, quad2[i], quad2[i]);
 147          gluTessEndContour(tobj);
 148          gluTessBeginContour(tobj);
 149          for (i = 0; i < 3; i++)
 150             gluTessVertex(tobj, tri[i], tri[i]);
 151          gluTessEndContour(tobj);
 152       gluTessEndPolygon(tobj);
 153    glEndList();
 154 }
 155
 156 static void display (void) {
 157    glClear(GL_COLOR_BUFFER_BIT);
 158    glColor3f(1.0, 1.0, 1.0);
 159    glPushMatrix();
 160    glCallList(list);
 161    glTranslatef(0.0, 500.0, 0.0);
 162    glCallList(list+1);
 163    glTranslatef(500.0, -500.0, 0.0);
 164    glCallList(list+2);
 165    glTranslatef(0.0, 500.0, 0.0);
 166    glCallList(list+3);
 167    glPopMatrix();
 168    glFlush();
 169 }
 170
 171 static void CALLBACK beginCallback(GLenum which)
 172 {
 173    glBegin(which);
 174 }
 175
 176 static void CALLBACK errorCallback(GLenum errorCode)
 177 {
 178    const GLubyte *estring;
 179
 180    estring = gluErrorString(errorCode);
 181    fprintf(stderr, "Tessellation Error: %s\n", (char *) estring);
 182    exit(0);
 183 }
 184
 185 static void CALLBACK endCallback(void)
 186 {
 187    glEnd();
 188 }
 189
 190 /*  combineCallback is used to create a new vertex when edges
 191  *  intersect.  coordinate location is trivial to calculate,
 192  *  but weight[4] may be used to average color, normal, or texture
 193  *  coordinate data.
 194  */
 195 /* ARGSUSED */
 196 static void CALLBACK combineCallback(GLdouble coords[3], GLdouble *data[4],
 197                      GLfloat weight[4], GLdouble **dataOut )
 198 {
 199    GLdouble *vertex;
 200    vertex = (GLdouble *) malloc(3 * sizeof(GLdouble));
 201
 202    vertex[0] = coords[0];
 203    vertex[1] = coords[1];
 204    vertex[2] = coords[2];
 205    *dataOut = vertex;
 206 }
 207
 208 static void init(void)
 209 {
 210    glClearColor(0.0, 0.0, 0.0, 0.0);
 211    glShadeModel(GL_FLAT);
 212
 213    tobj = gluNewTess();
 214    gluTessCallback(tobj, GLU_TESS_VERTEX,
 215                    (GLvoid (CALLBACK*) ()) &glVertex3dv);
 216    gluTessCallback(tobj, GLU_TESS_BEGIN,
 217                    (GLvoid (CALLBACK*) ()) &beginCallback);
 218    gluTessCallback(tobj, GLU_TESS_END,
 219                    (GLvoid (CALLBACK*) ()) &endCallback);
 220    gluTessCallback(tobj, GLU_TESS_ERROR,
 221                    (GLvoid (CALLBACK*) ()) &errorCallback);
 222    gluTessCallback(tobj, GLU_TESS_COMBINE,
 223                    (GLvoid (CALLBACK*) ()) &combineCallback);
 224
 225    list = glGenLists(4);
 226    makeNewLists();
 227 }
 228
 229 static void reshape(int w, int h)
 230 {
 231    glViewport(0, 0, (GLsizei) w, (GLsizei) h);
 232    glMatrixMode(GL_PROJECTION);
 233    glLoadIdentity();
 234    if (w <= h)
 235       gluOrtho2D(0.0, 1000.0, 0.0, 1000.0 * (GLdouble)h/(GLdouble)w);
 236    else
 237       gluOrtho2D(0.0, 1000.0 * (GLdouble)w/(GLdouble)h, 0.0, 1000.0);
 238    glMatrixMode(GL_MODELVIEW);
 239    glLoadIdentity();
 240 }
 241
 242 /* ARGSUSED1 */
 243 static void keyboard(unsigned char key, int x, int y)
 244 {
 245    switch (key) {
 246       case 'w':
 247       case 'W':
 248          if (currentWinding == GLU_TESS_WINDING_ODD)
 249             currentWinding = GLU_TESS_WINDING_NONZERO;
 250          else if (currentWinding == GLU_TESS_WINDING_NONZERO)
 251             currentWinding = GLU_TESS_WINDING_POSITIVE;
 252          else if (currentWinding == GLU_TESS_WINDING_POSITIVE)
 253             currentWinding = GLU_TESS_WINDING_NEGATIVE;
 254          else if (currentWinding == GLU_TESS_WINDING_NEGATIVE)
 255             currentWinding = GLU_TESS_WINDING_ABS_GEQ_TWO;
 256          else if (currentWinding == GLU_TESS_WINDING_ABS_GEQ_TWO)
 257             currentWinding = GLU_TESS_WINDING_ODD;
 258          makeNewLists();
 259          glutPostRedisplay();
 260          break;
 261       case 27:
 262          exit(0);
 263          break;
 264       default:
 265          break;
 266    }
 267 }
 268
 269 int main(int argc, char** argv)
 270 {
 271    glutInit(&argc, argv);
 272    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
 273    glutInitWindowSize(500, 500);
 274    glutCreateWindow(argv[0]);
 275    init();
 276    glutDisplayFunc(display);
 277    glutReshapeFunc(reshape);
 278    glutKeyboardFunc(keyboard);
 279    glutMainLoop();
 280    return 0;
 281 }
 282
 283 #else
 284 int main(int argc, char** argv)
 285 {
 286     fprintf (stderr, "This program demonstrates the new tesselator API in GLU 1.2.\n");
 287     fprintf (stderr, "Your GLU library does not support this new interface, sorry.\n");
 288     return 0;
 289 }
 290 #endif