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 #define FRAME 50
  31
  32 #define BASESIZE 10.0
  33
  34 #define BASERES 12
  35 #define TEAPOTRES 3
  36
  37 #ifndef M_PI
  38 #define M_PI 3.1415926535
  39 #endif
  40
  41 extern void shadowmatrix(GLfloat [4][4], GLfloat [4], GLfloat [4]);
  42 extern void findplane(GLfloat [4], GLfloat [3], GLfloat [3], GLfloat [3]);
  43
  44
  45 static int win=0;
  46
  47 static float obs[3]={5.0,0.0,1.0};
  48 static float dir[3];
  49 static float v=0.0;
  50 static float alpha=-90.0;
  51 static float beta=90.0;
  52
  53 static GLfloat baseshadow[4][4];
  54 static GLfloat lightpos[4]={2.3,0.0,3.0,1.0};
  55 static GLfloat lightdir[3]={-2.3,0.0,-3.0};
  56 static GLfloat lightalpha=0.0;
  57
  58 static int fog=1;
  59 static int bfcull=1;
  60 static int usetex=1;
  61 static int help=1;
  62 static int joyavailable=0;
  63 static int joyactive=0;
  64
  65 static GLuint t1id,t2id;
  66 static GLuint teapotdlist,basedlist,lightdlist;
  67
  68 static float gettime(void)
  69 {
  70   static clock_t told=0;
  71   clock_t tnew,ris;
  72
  73   tnew=clock();
  74
  75   ris=tnew-told;
  76
  77   told=tnew;
  78
  79   return(ris/(float)CLOCKS_PER_SEC);
  80 }
  81
  82 static void calcposobs(void)
  83 {
  84   dir[0]=sin(alpha*M_PI/180.0);
  85   dir[1]=cos(alpha*M_PI/180.0)*sin(beta*M_PI/180.0);
  86   dir[2]=cos(beta*M_PI/180.0);
  87
  88   obs[0]+=v*dir[0];
  89   obs[1]+=v*dir[1];
  90   obs[2]+=v*dir[2];
  91 }
  92
  93 static void special(int k, int x, int y)
  94 {
  95   switch(k) {
  96   case GLUT_KEY_LEFT:
  97     alpha-=2.0;
  98     break;
  99   case GLUT_KEY_RIGHT:
 100     alpha+=2.0;
 101     break;
 102   case GLUT_KEY_DOWN:
 103     beta-=2.0;
 104     break;
 105   case GLUT_KEY_UP:
 106     beta+=2.0;
 107     break;
 108   }
 109 }
 110
 111 static void key(unsigned char k, int x, int y)
 112 {
 113   switch(k) {
 114   case 27:
 115     exit(0);
 116     break;
 117
 118   case 'a':
 119     v+=0.005;
 120     break;
 121   case 'z':
 122     v-=0.005;
 123     break;
 124
 125   case 'j':
 126     joyactive=(!joyactive);
 127     break;
 128   case 'h':
 129     help=(!help);
 130     break;
 131   case 'f':
 132     fog=(!fog);
 133     break;
 134   case 't':
 135     usetex=(!usetex);
 136     break;
 137   case 'b':
 138     if(bfcull) {
 139       glDisable(GL_CULL_FACE);
 140       bfcull=0;
 141     } else {
 142       glEnable(GL_CULL_FACE);
 143       bfcull=1;
 144     }
 145     break;
 146 #ifdef XMESA
 147   case ' ':
 148     XMesaSetFXmode(fullscreen ? XMESA_FX_FULLSCREEN : XMESA_FX_WINDOW);
 149     fullscreen=(!fullscreen);
 150     break;
 151 #endif
 152   }
 153 }
 154
 155 static void reshape(int w, int h)
 156 {
 157   WIDTH=w;
 158   HEIGHT=h;
 159   glMatrixMode(GL_PROJECTION);
 160   glLoadIdentity();
 161   gluPerspective(45.0,w/(float)h,0.2,40.0);
 162   glMatrixMode(GL_MODELVIEW);
 163   glLoadIdentity();
 164   glViewport(0,0,w,h);
 165 }
 166
 167 static void printstring(void *font, char *string)
 168 {
 169   int len,i;
 170
 171   len=(int)strlen(string);
 172   for(i=0;i<len;i++)
 173     glutBitmapCharacter(font,string[i]);
 174 }
 175
 176 static void printhelp(void)
 177 {
 178   glEnable(GL_BLEND);
 179   glColor4f(0.5,0.5,0.5,0.5);
 180   glRecti(40,40,600,440);
 181   glDisable(GL_BLEND);
 182
 183   glColor3f(1.0,0.0,0.0);
 184   glRasterPos2i(300,420);
 185   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Help");
 186
 187   glRasterPos2i(60,390);
 188   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"h - Togle Help");
 189   glRasterPos2i(60,360);
 190   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"t - Togle Textures");
 191   glRasterPos2i(60,330);
 192   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"f - Togle Fog");
 193   glRasterPos2i(60,300);
 194   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"b - Togle Back face culling");
 195   glRasterPos2i(60,270);
 196   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Arrow Keys - Rotate");
 197   glRasterPos2i(60,240);
 198   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"a - Increase velocity");
 199   glRasterPos2i(60,210);
 200   printstring(GLUT_BITMAP_TIMES_ROMAN_24,"z - Decrease velocity");
 201
 202   glRasterPos2i(60,180);
 203   if(joyavailable)
 204     printstring(GLUT_BITMAP_TIMES_ROMAN_24,"j - Togle jostick control (Joystick control available)");
 205   else
 206     printstring(GLUT_BITMAP_TIMES_ROMAN_24,"(No Joystick control available)");
 207 }
 208
 209 static void drawbase(void)
 210 {
 211   int i,j;
 212   float x,y,dx,dy;
 213
 214   glBindTexture(GL_TEXTURE_2D,t1id);
 215
 216   dx=BASESIZE/BASERES;
 217   dy=-BASESIZE/BASERES;
 218   for(y=BASESIZE/2.0,j=0;j<BASERES;y+=dy,j++) {
 219     glBegin(GL_QUAD_STRIP);
 220     glColor3f(1.0,1.0,1.0);
 221     glNormal3f(0.0,0.0,1.0);
 222     for(x=-BASESIZE/2.0,i=0;i<BASERES;x+=dx,i++) {
 223       glTexCoord2f(x,y);
 224       glVertex3f(x,y,0.0);
 225
 226       glTexCoord2f(x,y+dy);
 227       glVertex3f(x,y+dy,0.0);
 228     }
 229     glEnd();
 230   }
 231 }
 232
 233 static void drawteapot(void)
 234 {
 235   static float xrot=0.0;
 236   static float zrot=0.0;
 237
 238   glPushMatrix();
 239   glRotatef(lightalpha,0.0,0.0,1.0);
 240   glMultMatrixf((GLfloat *)baseshadow);
 241   glRotatef(-lightalpha,0.0,0.0,1.0);
 242
 243   glTranslatef(0.0,0.0,1.0);
 244   glRotatef(xrot,1.0,0.0,0.0);
 245   glRotatef(zrot,0.0,0.0,1.0);
 246
 247   glDisable(GL_TEXTURE_2D);
 248   glDisable(GL_DEPTH_TEST);
 249   glDisable(GL_LIGHTING);
 250
 251   glColor3f(0.0,0.0,0.0);
 252   glCallList(teapotdlist);
 253
 254   glEnable(GL_DEPTH_TEST);
 255   glEnable(GL_LIGHTING);
 256   if(usetex)
 257     glEnable(GL_TEXTURE_2D);
 258
 259   glPopMatrix();
 260
 261   glPushMatrix();
 262   glTranslatef(0.0,0.0,1.0);
 263   glRotatef(xrot,1.0,0.0,0.0);
 264   glRotatef(zrot,0.0,0.0,1.0);
 265
 266   glCallList(teapotdlist);
 267   glPopMatrix();
 268
 269   xrot+=2.0;
 270   zrot+=1.0;
 271 }
 272
 273 static void drawlight1(void)
 274 {
 275   glPushMatrix();
 276   glRotatef(lightalpha,0.0,0.0,1.0);
 277   glLightfv(GL_LIGHT0,GL_POSITION,lightpos);
 278   glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,lightdir);
 279
 280   glPopMatrix();
 281 }
 282
 283 static void drawlight2(void)
 284 {
 285   glPushMatrix();
 286   glRotatef(lightalpha,0.0,0.0,1.0);
 287   glTranslatef(lightpos[0],lightpos[1],lightpos[2]);
 288
 289   glDisable(GL_TEXTURE_2D);
 290   glCallList(lightdlist);
 291   if(usetex)
 292     glEnable(GL_TEXTURE_2D);
 293
 294   glPopMatrix();
 295
 296   lightalpha+=1.0;
 297 }
 298
 299 static void dojoy(void)
 300 {
 301 #ifdef WIN32
 302   static UINT max[2]={0,0};
 303   static UINT min[2]={0xffffffff,0xffffffff},center[2];
 304   MMRESULT res;
 305   JOYINFO joy;
 306
 307   res=joyGetPos(JOYSTICKID1,&joy);
 308
 309   if(res==JOYERR_NOERROR) {
 310     joyavailable=1;
 311
 312     if(max[0]<joy.wXpos)
 313       max[0]=joy.wXpos;
 314     if(min[0]>joy.wXpos)
 315       min[0]=joy.wXpos;
 316     center[0]=(max[0]+min[0])/2;
 317
 318     if(max[1]<joy.wYpos)
 319       max[1]=joy.wYpos;
 320     if(min[1]>joy.wYpos)
 321       min[1]=joy.wYpos;
 322     center[1]=(max[1]+min[1])/2;
 323
 324     if(joyactive) {
 325       if(fabs(center[0]-(float)joy.wXpos)>0.1*(max[0]-min[0]))
 326         alpha-=2.5*(center[0]-(float)joy.wXpos)/(max[0]-min[0]);
 327       if(fabs(center[1]-(float)joy.wYpos)>0.1*(max[1]-min[1]))
 328         beta+=2.5*(center[1]-(float)joy.wYpos)/(max[1]-min[1]);
 329
 330       if(joy.wButtons & JOY_BUTTON1)
 331         v+=0.005;
 332       if(joy.wButtons & JOY_BUTTON2)
 333         v-=0.005;
 334     }
 335   } else
 336     joyavailable=0;
 337 #endif
 338 }
 339
 340 static void draw(void)
 341 {
 342   static int count=0;
 343   static char frbuf[80];
 344   float fr;
 345
 346   dojoy();
 347
 348   glEnable(GL_DEPTH_TEST);
 349   glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
 350
 351   if(usetex)
 352     glEnable(GL_TEXTURE_2D);
 353   else
 354     glDisable(GL_TEXTURE_2D);
 355
 356   if(fog)
 357     glEnable(GL_FOG);
 358   else
 359     glDisable(GL_FOG);
 360
 361   glEnable(GL_LIGHTING);
 362
 363   glShadeModel(GL_SMOOTH);
 364
 365   glPushMatrix();
 366   calcposobs();
 367
 368   gluLookAt(obs[0],obs[1],obs[2],
 369             obs[0]+dir[0],obs[1]+dir[1],obs[2]+dir[2],
 370             0.0,0.0,1.0);
 371
 372   drawlight1();
 373   glCallList(basedlist);
 374   drawteapot();
 375   drawlight2();
 376   glPopMatrix();
 377
 378   if((count % FRAME)==0) {
 379     fr=gettime();
 380     sprintf(frbuf,"Frame rate: %f",FRAME/fr);
 381   }
 382
 383   glDisable(GL_LIGHTING);
 384   glDisable(GL_TEXTURE_2D);
 385   glDisable(GL_DEPTH_TEST);
 386   glDisable(GL_FOG);
 387   glShadeModel(GL_FLAT);
 388
 389   glMatrixMode(GL_PROJECTION);
 390   glLoadIdentity();
 391   glOrtho(-0.5,639.5,-0.5,479.5,-1.0,1.0);
 392   glMatrixMode(GL_MODELVIEW);
 393   glLoadIdentity();
 394
 395   glColor3f(1.0,0.0,0.0);
 396   glRasterPos2i(10,10);
 397   printstring(GLUT_BITMAP_HELVETICA_18,frbuf);
 398   glRasterPos2i(350,470);
 399   printstring(GLUT_BITMAP_HELVETICA_10,"Teapot V1.2 Written by David Bucciarelli (tech.hmw@plus.it)");
 400
 401   if(help)
 402     printhelp();
 403
 404   reshape(WIDTH,HEIGHT);
 405
 406   glutSwapBuffers();
 407
 408   count++;
 409 }
 410
 411 static void inittextures(void)
 412 {
 413   glGenTextures(1,&t1id);
 414   glBindTexture(GL_TEXTURE_2D,t1id);
 415
 416   glPixelStorei(GL_UNPACK_ALIGNMENT,4);
 417   if (!LoadRGBMipmaps("../images/tile.rgb", GL_RGB)) {
 418     fprintf(stderr,"Error reading a texture.\n");
 419     exit(-1);
 420   }
 421
 422   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
 423   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
 424
 425   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
 426   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
 427
 428   glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
 429
 430   glGenTextures(1,&t2id);
 431   glBindTexture(GL_TEXTURE_2D,t2id);
 432
 433   if (!LoadRGBMipmaps("../images/bw.rgb", GL_RGB)) {
 434     fprintf(stderr,"Error reading a texture.\n");
 435     exit(-1);
 436   }
 437
 438   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
 439   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
 440
 441   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
 442   glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
 443
 444   glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
 445 }
 446
 447 static void initlight(void)
 448 {
 449   float lamb[4]={0.2,0.2,0.2,1.0};
 450   float lspec[4]={1.0,1.0,1.0,1.0};
 451
 452   glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,70.0);
 453   glLightf(GL_LIGHT0,GL_SPOT_EXPONENT,20.0);
 454   glLightfv(GL_LIGHT0,GL_AMBIENT,lamb);
 455   glLightfv(GL_LIGHT0,GL_SPECULAR,lspec);
 456
 457   glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,20.0);
 458   glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,lspec);
 459
 460   glEnable(GL_LIGHT0);
 461 }
 462
 463 static void initdlists(void)
 464 {
 465   GLUquadricObj *lcone,*lbase;
 466   GLfloat plane[4];
 467   GLfloat v0[3]={0.0,0.0,0.0};
 468   GLfloat v1[3]={1.0,0.0,0.0};
 469   GLfloat v2[3]={0.0,1.0,0.0};
 470
 471   findplane(plane,v0,v1,v2);
 472   shadowmatrix(baseshadow,plane,lightpos);
 473
 474   teapotdlist=glGenLists(1);
 475   glNewList(teapotdlist,GL_COMPILE);
 476   glRotatef(90.0,1.0,0.0,0.0);
 477   glCullFace(GL_FRONT);
 478   glBindTexture(GL_TEXTURE_2D,t2id);
 479   glutSolidTeapot(0.75);
 480   glCullFace(GL_BACK);
 481   glEndList();
 482
 483   basedlist=glGenLists(1);
 484   glNewList(basedlist,GL_COMPILE);
 485   drawbase();
 486   glEndList();
 487
 488   lightdlist=glGenLists(1);
 489   glNewList(lightdlist,GL_COMPILE);
 490   glDisable(GL_LIGHTING);
 491
 492   lcone=gluNewQuadric();
 493   lbase=gluNewQuadric();
 494   glRotatef(45.0,0.0,1.0,0.0);
 495
 496   glColor3f(1.0,1.0,1.0);
 497   glCullFace(GL_FRONT);
 498   gluDisk(lbase,0.0,0.2,12.0,1.0);
 499   glCullFace(GL_BACK);
 500
 501   glColor3f(0.5,0.0,0.0);
 502   gluCylinder(lcone,0.2,0.0,0.5,12,1);
 503
 504   gluDeleteQuadric(lcone);
 505   gluDeleteQuadric(lbase);
 506
 507   glEnable(GL_LIGHTING);
 508   glEndList();
 509 }
 510
 511 int main(int ac, char **av)
 512 {
 513   float fogcolor[4]={0.025,0.025,0.025,1.0};
 514
 515   fprintf(stderr,"Teapot V1.2\nWritten by David Bucciarelli (tech.hmw@plus.it)\n");
 516
 517   /*
 518     if(!SetPriorityClass(GetCurrentProcess(),REALTIME_PRIORITY_CLASS)) {
 519     fprintf(stderr,"Error setting the process class.\n");
 520     return 0;
 521     }
 522
 523     if(!SetThreadPriority(GetCurrentThread(),THREAD_PRIORITY_TIME_CRITICAL)) {
 524     fprintf(stderr,"Error setting the process priority.\n");
 525     return 0;
 526     }
 527     */
 528
 529   glutInitWindowPosition(0,0);
 530   glutInitWindowSize(WIDTH,HEIGHT);
 531   glutInit(&ac,av);
 532
 533   glutInitDisplayMode(GLUT_RGB|GLUT_DEPTH|GLUT_DOUBLE);
 534
 535   if(!(win=glutCreateWindow("Teapot"))) {
 536     fprintf(stderr,"Error, couldn't open window\n");
 537         return -1;
 538   }
 539
 540   reshape(WIDTH,HEIGHT);
 541
 542   glShadeModel(GL_SMOOTH);
 543   glEnable(GL_DEPTH_TEST);
 544   glEnable(GL_CULL_FACE);
 545   glEnable(GL_TEXTURE_2D);
 546
 547   glEnable(GL_FOG);
 548   glFogi(GL_FOG_MODE,GL_EXP2);
 549   glFogfv(GL_FOG_COLOR,fogcolor);
 550
 551   glFogf(GL_FOG_DENSITY,0.04);
 552   glHint(GL_FOG_HINT,GL_NICEST);
 553   glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
 554
 555   calcposobs();
 556
 557   inittextures();
 558   initlight();
 559
 560   initdlists();
 561
 562   glClearColor(fogcolor[0],fogcolor[1],fogcolor[2],fogcolor[3]);
 563
 564   glutReshapeFunc(reshape);
 565   glutDisplayFunc(draw);
 566   glutKeyboardFunc(key);
 567   glutSpecialFunc(special);
 568   glutIdleFunc(draw);
 569
 570   glutMainLoop();
 571
 572   return 0;
 573 }