progs/demos/teapot.c

   1 /*
   2  * This program is under the GNU GPL.
   3  * Use at your own risk.
   4  *
   5  * written by David Bucciarelli (tech.hmw@plus.it)
   6  *            Humanware s.r.l.
   7  */
   8
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <math.h>
  12 #include <time.h>
  13
  14 #ifdef WIN32
  15 #include <windows.h>
  16 #endif
  17
  18 #include <GL/glut.h>
  19 #include "../util/readtex.c"
  20 #include "shadow.c"
  21
  22 #ifdef XMESA
  23 #include "GL/xmesa.h"
  24 static int fullscreen=1;
  25 #endif
  26
  27 static int WIDTH=640;
  28 static int HEIGHT=480;
  29
  30 static GLint T0 = 0;
  31 static GLint Frames = 0;
  32
  33 #define BASESIZE 10.0
  34
  35 #define BASERES 12
  36 #define TEAPOTRES 3
  37
  38 #ifndef M_PI
  39 #define M_PI 3.1415926535
  40 #endif
  41
  42 extern void shadowmatrix(GLfloat [4][4], GLfloat [4], GLfloat [4]);
  43 extern void findplane(GLfloat [4], GLfloat [3], GLfloat [3], GLfloat [3]);
  44
  45
  46 static int win=0;
  47
  48 static float obs[3]={5.0,0.0,1.0};
  49 static float dir[3];
  50 static float v=0.0;
  51 static float alpha=-90.0;
  52 static float beta=90.0;
  53
  54 static GLfloat baseshadow[4][4];
  55 static GLfloat lightpos[4]={2.3,0.0,3.0,1.0};
  56 static GLfloat lightdir[3]={-2.3,0.0,-3.0};
  57 static GLfloat lightalpha=0.0;
  58
  59 static int fog=1;
  60 static int bfcull=1;
  61 static int usetex=1;
  62 static int help=1;
  63 static int joyavailable=0;
  64 static int joyactive=0;
  65
  66 static GLuint t1id,t2id;
  67 static GLuint teapotdlist,basedlist,lightdlist;
  68
  69 static void calcposobs(void)
  70 {
  71   dir[0]=sin(alpha*M_PI/180.0);
  72   dir[1]=cos(alpha*M_PI/180.0)*sin(beta*M_PI/180.0);
  73   dir[2]=cos(beta*M_PI/180.0);
  74
  75   obs[0]+=v*dir[0];
  76   obs[1]+=v*dir[1];
  77   obs[2]+=v*dir[2];
  78 }
  79
  80 static void special(int k, int x, int y)
  81 {
  82   switch(k) {
  83   case GLUT_KEY_LEFT:
  84     alpha-=2.0;
  85     break;
  86   case GLUT_KEY_RIGHT:
  87     alpha+=2.0;
  88     break;
  89   case GLUT_KEY_DOWN:
  90     beta-=2.0;
  91     break;
  92   case GLUT_KEY_UP:
  93     beta+=2.0;
  94     break;
  95   }
  96 }
  97
  98 static void key(unsigned char k, int x, int y)
  99 {
 100   switch(k) {
 101   case 27:
 102     exit(0);
 103     break;
 104
 105   case 'a':
 106     v+=0.005;
 107     break;
 108   case 'z':
 109     v-=0.005;
 110     break;
 111
 112   case 'j':
 113     joyactive=(!joyactive);
 114     break;
 115   case 'h':
 116     help=(!help);
 117     break;
 118   case 'f':
 119     fog=(!fog);
 120     break;
 121   case 't':
 122     usetex=(!usetex);
 123     break;
 124   case 'b':
 125     if(bfcull) {
 126       glDisable(GL_CULL_FACE);
 127       bfcull=0;
 128     } else {
 129       glEnable(GL_CULL_FACE);
 130       bfcull=1;
 131     }
 132     break;
 133 #ifdef XMESA
 134   case ' ':
 135     XMesaSetFXmode(fullscreen ? XMESA_FX_FULLSCREEN : XMESA_FX_WINDOW);
 136     fullscreen=(!fullscreen);
 137     break;
 138 #endif
 139   }
 140 }
 141
 142 static void reshape(int w, int h)
 143 {
 144   WIDTH=w;
 145   HEIGHT=h;
 146   glMatrixMode(GL_PROJECTION);
 147   glLoadIdentity();
 148   gluPerspective(45.0,w/(float)h,0.2,40.0);
 149   glMatrixMode(GL_MODELVIEW);
 150   glLoadIdentity();
 151   glViewport(0,0,w,h);
 152 }
 153
 154 static void printstring(void *font, char *string)
 155 {
 156   int len,i;
 157
 158   len=(int)strlen(string);
 159   for(i=0;i<len;i++)
 160     glutBitmapCharacter(font,string[i]);
 161 }
 162
 163 static void printhelp(void)
 164 {
 165   glEnable(GL_BLEND);
 166   glColor4f(0.5,0.5,0.5,0.5);
 167   glRecti(40,40,600,440);
 168   glDisable(GL_BLEND);
 169
 170   glColor3f(1.0,0.0,0.0);
 171   glRasterPos2i(300,420);
 172   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Help");
 173
 174   glRasterPos2i(60,390);
 175   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"h - Togle Help");
 176   glRasterPos2i(60,360);
 177   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"t - Togle Textures");
 178   glRasterPos2i(60,330);
 179   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"f - Togle Fog");
 180   glRasterPos2i(60,300);
 181   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"b - Togle Back face culling");
 182   glRasterPos2i(60,270);
 183   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Arrow Keys - Rotate");
 184   glRasterPos2i(60,240);
 185   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"a - Increase velocity");
 186   glRasterPos2i(60,210);
 187   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"z - Decrease velocity");
 188
 189   glRasterPos2i(60,180);
 190   if(joyavailable)
 191     printstring(GLUT_BITMAP_TIMES_ROMAN_24,"j - Togle jostick control (Joystick control available)");
 192   else
 193     printstring(GLUT_BITMAP_TIMES_ROMAN_24,"(No Joystick control available)");
 194 }
 195
 196 static void drawbase(void)
 197 {
 198   int i,j;
 199   float x,y,dx,dy;
 200
 201   glBindTexture(GL_TEXTURE_2D,t1id);
 202
 203   dx=BASESIZE/BASERES;
 204   dy=-BASESIZE/BASERES;
 205   for(y=BASESIZE/2.0,j=0;j<BASERES;y+=dy,j++) {
 206     glBegin(GL_QUAD_STRIP);
 207     glColor3f(1.0,1.0,1.0);
 208     glNormal3f(0.0,0.0,1.0);
 209     for(x=-BASESIZE/2.0,i=0;i<BASERES;x+=dx,i++) {
 210       glTexCoord2f(x,y);
 211       glVertex3f(x,y,0.0);
 212
 213       glTexCoord2f(x,y+dy);
 214       glVertex3f(x,y+dy,0.0);
 215     }
 216     glEnd();
 217   }
 218 }
 219
 220 static void drawteapot(void)
 221 {
 222   static float xrot=0.0;
 223   static float zrot=0.0;
 224
 225   glPushMatrix();
 226   glRotatef(lightalpha,0.0,0.0,1.0);
 227   glMultMatrixf((GLfloat *)baseshadow);
 228   glRotatef(-lightalpha,0.0,0.0,1.0);
 229
 230   glTranslatef(0.0,0.0,1.0);
 231   glRotatef(xrot,1.0,0.0,0.0);
 232   glRotatef(zrot,0.0,0.0,1.0);
 233
 234   glDisable(GL_TEXTURE_2D);
 235   glDisable(GL_DEPTH_TEST);
 236   glDisable(GL_LIGHTING);
 237
 238   glColor3f(0.0,0.0,0.0);
 239   glCallList(teapotdlist);
 240
 241   glEnable(GL_DEPTH_TEST);
 242   glEnable(GL_LIGHTING);
 243   if(usetex)
 244     glEnable(GL_TEXTURE_2D);
 245
 246   glPopMatrix();
 247
 248   glPushMatrix();
 249   glTranslatef(0.0,0.0,1.0);
 250   glRotatef(xrot,1.0,0.0,0.0);
 251   glRotatef(zrot,0.0,0.0,1.0);
 252
 253   glCallList(teapotdlist);
 254   glPopMatrix();
 255
 256   xrot+=2.0;
 257   zrot+=1.0;
 258 }
 259
 260 static void drawlight1(void)
 261 {
 262   glPushMatrix();
 263   glRotatef(lightalpha,0.0,0.0,1.0);
 264   glLightfv(GL_LIGHT0,GL_POSITION,lightpos);
 265   glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,lightdir);
 266
 267   glPopMatrix();
 268 }
 269
 270 static void drawlight2(void)
 271 {
 272   glPushMatrix();
 273   glRotatef(lightalpha,0.0,0.0,1.0);
 274   glTranslatef(lightpos[0],lightpos[1],lightpos[2]);
 275
 276   glDisable(GL_TEXTURE_2D);
 277   glCallList(lightdlist);
 278   if(usetex)
 279     glEnable(GL_TEXTURE_2D);
 280
 281   glPopMatrix();
 282
 283   lightalpha+=1.0;
 284 }
 285
 286 static void dojoy(void)
 287 {
 288 #ifdef WIN32
 289   static UINT max[2]={0,0};
 290   static UINT min[2]={0xffffffff,0xffffffff},center[2];
 291   MMRESULT res;
 292   JOYINFO joy;
 293
 294   res=joyGetPos(JOYSTICKID1,&joy);
 295
 296   if(res==JOYERR_NOERROR) {
 297     joyavailable=1;
 298
 299     if(max[0]<joy.wXpos)
 300       max[0]=joy.wXpos;
 301     if(min[0]>joy.wXpos)
 302       min[0]=joy.wXpos;
 303     center[0]=(max[0]+min[0])/2;
 304
 305     if(max[1]<joy.wYpos)
 306       max[1]=joy.wYpos;
 307     if(min[1]>joy.wYpos)
 308       min[1]=joy.wYpos;
 309     center[1]=(max[1]+min[1])/2;
 310
 311     if(joyactive) {
 312       if(fabs(center[0]-(float)joy.wXpos)>0.1*(max[0]-min[0]))
 313         alpha-=2.5*(center[0]-(float)joy.wXpos)/(max[0]-min[0]);
 314       if(fabs(center[1]-(float)joy.wYpos)>0.1*(max[1]-min[1]))
 315         beta+=2.5*(center[1]-(float)joy.wYpos)/(max[1]-min[1]);
 316
 317       if(joy.wButtons & JOY_BUTTON1)
 318         v+=0.005;
 319       if(joy.wButtons & JOY_BUTTON2)
 320         v-=0.005;
 321     }
 322   } else
 323     joyavailable=0;
 324 #endif
 325 }
 326
 327 static void draw(void)
 328 {
 329   static char frbuf[80] = "";
 330
 331   dojoy();
 332
 333   glEnable(GL_DEPTH_TEST);
 334   glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
 335
 336   if(usetex)
 337     glEnable(GL_TEXTURE_2D);
 338   else
 339     glDisable(GL_TEXTURE_2D);
 340
 341   if(fog)
 342     glEnable(GL_FOG);
 343   else
 344     glDisable(GL_FOG);
 345
 346   glEnable(GL_LIGHTING);
 347
 348   glShadeModel(GL_SMOOTH);
 349
 350   glPushMatrix();
 351   calcposobs();
 352
 353   gluLookAt(obs[0],obs[1],obs[2],
 354             obs[0]+dir[0],obs[1]+dir[1],obs[2]+dir[2],
 355             0.0,0.0,1.0);
 356
 357   drawlight1();
 358   glCallList(basedlist);
 359   drawteapot();
 360   drawlight2();
 361   glPopMatrix();
 362
 363   glDisable(GL_LIGHTING);
 364   glDisable(GL_TEXTURE_2D);
 365   glDisable(GL_DEPTH_TEST);
 366   glDisable(GL_FOG);
 367   glShadeModel(GL_FLAT);
 368
 369   glMatrixMode(GL_PROJECTION);
 370   glLoadIdentity();
 371   glOrtho(-0.5,639.5,-0.5,479.5,-1.0,1.0);
 372   glMatrixMode(GL_MODELVIEW);
 373   glLoadIdentity();
 374
 375   glColor3f(1.0,0.0,0.0);
 376   glRasterPos2i(10,10);
 377   printstring(GLUT_BITMAP_HELVETICA_18,frbuf);
 378   glRasterPos2i(350,470);
 379   printstring(GLUT_BITMAP_HELVETICA_10,"Teapot V1.2 Written by David Bucciarelli (tech.hmw@plus.it)");
 380
 381   if(help)
 382     printhelp();
 383
 384   reshape(WIDTH,HEIGHT);
 385
 386   glutSwapBuffers();
 387
 388    Frames++;
 389
 390    {
 391       GLint t = glutGet(GLUT_ELAPSED_TIME);
 392       if (t - T0 >= 2000) {
 393          GLfloat seconds = (t - T0) / 1000.0;
 394          GLfloat fps = Frames / seconds;
 395          sprintf(frbuf, "Frame rate: %f", fps);
 396          T0 = t;
 397          Frames = 0;
 398       }
 399    }
 400 }
 401
 402 static void inittextures(void)
 403 {
 404   glGenTextures(1,&t1id);
 405   glBindTexture(GL_TEXTURE_2D,t1id);
 406
 407   glPixelStorei(GL_UNPACK_ALIGNMENT,4);
 408   if (!LoadRGBMipmaps("../images/tile.rgb", GL_RGB)) {
 409     fprintf(stderr,"Error reading a texture.\n");
 410     exit(-1);
 411   }
 412
 413   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
 414   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
 415
 416   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
 417   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
 418
 419   glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
 420
 421   glGenTextures(1,&t2id);
 422   glBindTexture(GL_TEXTURE_2D,t2id);
 423
 424   if (!LoadRGBMipmaps("../images/bw.rgb", GL_RGB)) {
 425     fprintf(stderr,"Error reading a texture.\n");
 426     exit(-1);
 427   }
 428
 429   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
 430   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
 431
 432   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
 433   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
 434
 435   glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
 436 }
 437
 438 static void initlight(void)
 439 {
 440   float lamb[4]={0.2,0.2,0.2,1.0};
 441   float lspec[4]={1.0,1.0,1.0,1.0};
 442
 443   glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,70.0);
 444   glLightf(GL_LIGHT0,GL_SPOT_EXPONENT,20.0);
 445   glLightfv(GL_LIGHT0,GL_AMBIENT,lamb);
 446   glLightfv(GL_LIGHT0,GL_SPECULAR,lspec);
 447
 448   glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,20.0);
 449   glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,lspec);
 450
 451   glEnable(GL_LIGHT0);
 452 }
 453
 454 static void initdlists(void)
 455 {
 456   GLUquadricObj *lcone,*lbase;
 457   GLfloat plane[4];
 458   GLfloat v0[3]={0.0,0.0,0.0};
 459   GLfloat v1[3]={1.0,0.0,0.0};
 460   GLfloat v2[3]={0.0,1.0,0.0};
 461
 462   findplane(plane,v0,v1,v2);
 463   shadowmatrix(baseshadow,plane,lightpos);
 464
 465   teapotdlist=glGenLists(1);
 466   glNewList(teapotdlist,GL_COMPILE);
 467   glRotatef(90.0,1.0,0.0,0.0);
 468   glCullFace(GL_FRONT);
 469   glBindTexture(GL_TEXTURE_2D,t2id);
 470   glutSolidTeapot(0.75);
 471   glCullFace(GL_BACK);
 472   glEndList();
 473
 474   basedlist=glGenLists(1);
 475   glNewList(basedlist,GL_COMPILE);
 476   drawbase();
 477   glEndList();
 478
 479   lightdlist=glGenLists(1);
 480   glNewList(lightdlist,GL_COMPILE);
 481   glDisable(GL_LIGHTING);
 482
 483   lcone=gluNewQuadric();
 484   lbase=gluNewQuadric();
 485   glRotatef(45.0,0.0,1.0,0.0);
 486
 487   glColor3f(1.0,1.0,1.0);
 488   glCullFace(GL_FRONT);
 489   gluDisk(lbase,0.0,0.2,12.0,1.0);
 490   glCullFace(GL_BACK);
 491
 492   glColor3f(0.5,0.0,0.0);
 493   gluCylinder(lcone,0.2,0.0,0.5,12,1);
 494
 495   gluDeleteQuadric(lcone);
 496   gluDeleteQuadric(lbase);
 497
 498   glEnable(GL_LIGHTING);
 499   glEndList();
 500 }
 501
 502 int main(int ac, char **av)
 503 {
 504   float fogcolor[4]={0.025,0.025,0.025,1.0};
 505
 506   fprintf(stderr,"Teapot V1.2\nWritten by David Bucciarelli (tech.hmw@plus.it)\n");
 507
 508   /*
 509     if(!SetPriorityClass(GetCurrentProcess(),REALTIME_PRIORITY_CLASS)) {
 510     fprintf(stderr,"Error setting the process class.\n");
 511     return 0;
 512     }
 513
 514     if(!SetThreadPriority(GetCurrentThread(),THREAD_PRIORITY_TIME_CRITICAL)) {
 515     fprintf(stderr,"Error setting the process priority.\n");
 516     return 0;
 517     }
 518     */
 519
 520   glutInitWindowPosition(0,0);
 521   glutInitWindowSize(WIDTH,HEIGHT);
 522   glutInit(&ac,av);
 523
 524   glutInitDisplayMode(GLUT_RGB|GLUT_DEPTH|GLUT_DOUBLE);
 525
 526   if(!(win=glutCreateWindow("Teapot"))) {
 527     fprintf(stderr,"Error, couldn't open window\n");
 528         return -1;
 529   }
 530
 531   reshape(WIDTH,HEIGHT);
 532
 533   glShadeModel(GL_SMOOTH);
 534   glEnable(GL_DEPTH_TEST);
 535   glEnable(GL_CULL_FACE);
 536   glEnable(GL_TEXTURE_2D);
 537
 538   glEnable(GL_FOG);
 539   glFogi(GL_FOG_MODE,GL_EXP2);
 540   glFogfv(GL_FOG_COLOR,fogcolor);
 541
 542   glFogf(GL_FOG_DENSITY,0.04);
 543   glHint(GL_FOG_HINT,GL_NICEST);
 544   glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
 545
 546   calcposobs();
 547
 548   inittextures();
 549   initlight();
 550
 551   initdlists();
 552
 553   glClearColor(fogcolor[0],fogcolor[1],fogcolor[2],fogcolor[3]);
 554
 555   glutReshapeFunc(reshape);
 556   glutDisplayFunc(draw);
 557   glutKeyboardFunc(key);
 558   glutSpecialFunc(special);
 559   glutIdleFunc(draw);
 560
 561   glutMainLoop();
 562
 563   return 0;
 564 }