2 * This program is under the GNU GPL.
3 * Use at your own risk.
5 * written by David Bucciarelli (tech.hmw@plus.it)
24 static int fullscreen=1;
28 static int HEIGHT=480;
31 static GLint Frames = 0;
39 #define M_PI 3.1415926535
42 extern void shadowmatrix(GLfloat [4][4], GLfloat [4], GLfloat [4]);
43 extern void findplane(GLfloat [4], GLfloat [3], GLfloat [3], GLfloat [3]);
48 static float obs[3]={5.0,0.0,1.0};
51 static float alpha=-90.0;
52 static float beta=90.0;
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;
63 static int joyavailable=0;
64 static int joyactive=0;
66 static GLuint t1id,t2id;
67 static GLuint teapotdlist,basedlist,lightdlist;
71 /******************** begin shadow code ********************/
73 /* Taken from the projshadow.c - by Tom McReynolds, SGI */
75 /* Modified by David Bucciarelli */
84 /* create a matrix that will project the desired shadow */
86 shadowmatrix(GLfloat shadowMat[4][4],
87 GLfloat groundplane[4],
92 /* find dot product between light position vector and ground plane normal */
93 dot = groundplane[X] * lightpos[X] +
94 groundplane[Y] * lightpos[Y] +
95 groundplane[Z] * lightpos[Z] +
96 groundplane[W] * lightpos[W];
98 shadowMat[0][0] = dot - lightpos[X] * groundplane[X];
99 shadowMat[1][0] = 0.f - lightpos[X] * groundplane[Y];
100 shadowMat[2][0] = 0.f - lightpos[X] * groundplane[Z];
101 shadowMat[3][0] = 0.f - lightpos[X] * groundplane[W];
103 shadowMat[X][1] = 0.f - lightpos[Y] * groundplane[X];
104 shadowMat[1][1] = dot - lightpos[Y] * groundplane[Y];
105 shadowMat[2][1] = 0.f - lightpos[Y] * groundplane[Z];
106 shadowMat[3][1] = 0.f - lightpos[Y] * groundplane[W];
108 shadowMat[X][2] = 0.f - lightpos[Z] * groundplane[X];
109 shadowMat[1][2] = 0.f - lightpos[Z] * groundplane[Y];
110 shadowMat[2][2] = dot - lightpos[Z] * groundplane[Z];
111 shadowMat[3][2] = 0.f - lightpos[Z] * groundplane[W];
113 shadowMat[X][3] = 0.f - lightpos[W] * groundplane[X];
114 shadowMat[1][3] = 0.f - lightpos[W] * groundplane[Y];
115 shadowMat[2][3] = 0.f - lightpos[W] * groundplane[Z];
116 shadowMat[3][3] = dot - lightpos[W] * groundplane[W];
120 /* find the plane equation given 3 points */
122 findplane(GLfloat plane[4],
123 GLfloat v0[3], GLfloat v1[3], GLfloat v2[3])
125 GLfloat vec0[3], vec1[3];
127 /* need 2 vectors to find cross product */
128 vec0[X] = v1[X] - v0[X];
129 vec0[Y] = v1[Y] - v0[Y];
130 vec0[Z] = v1[Z] - v0[Z];
132 vec1[X] = v2[X] - v0[X];
133 vec1[Y] = v2[Y] - v0[Y];
134 vec1[Z] = v2[Z] - v0[Z];
136 /* find cross product to get A, B, and C of plane equation */
137 plane[A] = vec0[Y] * vec1[Z] - vec0[Z] * vec1[Y];
138 plane[B] = -(vec0[X] * vec1[Z] - vec0[Z] * vec1[X]);
139 plane[C] = vec0[X] * vec1[Y] - vec0[Y] * vec1[X];
141 plane[D] = -(plane[A] * v0[X] + plane[B] * v0[Y] + plane[C] * v0[Z]);
144 /******************** end shadow code ********************/
147 static void calcposobs(void)
149 dir[0]=sin(alpha*M_PI/180.0);
150 dir[1]=cos(alpha*M_PI/180.0)*sin(beta*M_PI/180.0);
151 dir[2]=cos(beta*M_PI/180.0);
158 static void special(int k, int x, int y)
176 static void key(unsigned char k, int x, int y)
191 joyactive=(!joyactive);
204 glDisable(GL_CULL_FACE);
207 glEnable(GL_CULL_FACE);
213 XMesaSetFXmode(fullscreen ? XMESA_FX_FULLSCREEN : XMESA_FX_WINDOW);
214 fullscreen=(!fullscreen);
220 static void reshape(int w, int h)
224 glMatrixMode(GL_PROJECTION);
226 gluPerspective(45.0,w/(float)h,0.2,40.0);
227 glMatrixMode(GL_MODELVIEW);
232 static void printstring(void *font, char *string)
236 len=(int)strlen(string);
238 glutBitmapCharacter(font,string[i]);
241 static void printhelp(void)
244 glColor4f(0.5,0.5,0.5,0.5);
245 glRecti(40,40,600,440);
248 glColor3f(1.0,0.0,0.0);
249 glRasterPos2i(300,420);
250 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Help");
252 glRasterPos2i(60,390);
253 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"h - Togle Help");
254 glRasterPos2i(60,360);
255 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"t - Togle Textures");
256 glRasterPos2i(60,330);
257 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"f - Togle Fog");
258 glRasterPos2i(60,300);
259 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"b - Togle Back face culling");
260 glRasterPos2i(60,270);
261 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"Arrow Keys - Rotate");
262 glRasterPos2i(60,240);
263 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"a - Increase velocity");
264 glRasterPos2i(60,210);
265 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"z - Decrease velocity");
267 glRasterPos2i(60,180);
269 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"j - Togle jostick control (Joystick control available)");
271 printstring(GLUT_BITMAP_TIMES_ROMAN_24,"(No Joystick control available)");
274 static void drawbase(void)
276 static const GLfloat amb[4] = { 1, .5, 0.2, 1 };
277 static const GLfloat diff[4] = { 1, .4, 0.2, 1 };
281 glBindTexture(GL_TEXTURE_2D,t1id);
283 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, amb);
284 glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, diff);
286 dy=-BASESIZE/BASERES;
287 for(y=BASESIZE/2.0,j=0;j<BASERES;y+=dy,j++) {
288 glBegin(GL_QUAD_STRIP);
289 glColor3f(1.0,1.0,1.0);
290 glNormal3f(0.0,0.0,1.0);
291 for(x=-BASESIZE/2.0,i=0;i<BASERES;x+=dx,i++) {
295 glTexCoord2f(x,y+dy);
296 glVertex3f(x,y+dy,0.0);
302 static void drawteapot(void)
304 static const GLfloat amb[4] = { 0.2, 0.2, 0.2, 1 };
305 static const GLfloat diff[4] = { 0.8, 0.3, 0.5, 1 };
306 static float xrot=0.0;
307 static float zrot=0.0;
309 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, amb);
310 glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, diff);
313 glRotatef(lightalpha,0.0,0.0,1.0);
314 glMultMatrixf((GLfloat *)baseshadow);
315 glRotatef(-lightalpha,0.0,0.0,1.0);
317 glTranslatef(0.0,0.0,1.0);
318 glRotatef(xrot,1.0,0.0,0.0);
319 glRotatef(zrot,0.0,0.0,1.0);
321 glDisable(GL_TEXTURE_2D);
322 glDisable(GL_DEPTH_TEST);
323 glDisable(GL_LIGHTING);
325 glColor3f(0.0,0.0,0.0);
326 glCallList(teapotdlist);
328 glEnable(GL_DEPTH_TEST);
329 glEnable(GL_LIGHTING);
331 glEnable(GL_TEXTURE_2D);
336 glTranslatef(0.0,0.0,1.0);
337 glRotatef(xrot,1.0,0.0,0.0);
338 glRotatef(zrot,0.0,0.0,1.0);
340 glCallList(teapotdlist);
347 static void drawlight1(void)
350 glRotatef(lightalpha,0.0,0.0,1.0);
351 glLightfv(GL_LIGHT0,GL_POSITION,lightpos);
352 glLightfv(GL_LIGHT0,GL_SPOT_DIRECTION,lightdir);
357 static void drawlight2(void)
360 glRotatef(lightalpha,0.0,0.0,1.0);
361 glTranslatef(lightpos[0],lightpos[1],lightpos[2]);
363 glDisable(GL_TEXTURE_2D);
364 glCallList(lightdlist);
366 glEnable(GL_TEXTURE_2D);
373 static void dojoy(void)
376 static UINT max[2]={0,0};
377 static UINT min[2]={0xffffffff,0xffffffff},center[2];
381 res=joyGetPos(JOYSTICKID1,&joy);
383 if(res==JOYERR_NOERROR) {
390 center[0]=(max[0]+min[0])/2;
396 center[1]=(max[1]+min[1])/2;
399 if(fabs(center[0]-(float)joy.wXpos)>0.1*(max[0]-min[0]))
400 alpha-=2.5*(center[0]-(float)joy.wXpos)/(max[0]-min[0]);
401 if(fabs(center[1]-(float)joy.wYpos)>0.1*(max[1]-min[1]))
402 beta+=2.5*(center[1]-(float)joy.wYpos)/(max[1]-min[1]);
404 if(joy.wButtons & JOY_BUTTON1)
406 if(joy.wButtons & JOY_BUTTON2)
414 static void draw(void)
416 static char frbuf[80] = "";
420 glEnable(GL_DEPTH_TEST);
421 glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
424 glEnable(GL_TEXTURE_2D);
426 glDisable(GL_TEXTURE_2D);
433 glEnable(GL_LIGHTING);
435 glShadeModel(GL_SMOOTH);
440 gluLookAt(obs[0],obs[1],obs[2],
441 obs[0]+dir[0],obs[1]+dir[1],obs[2]+dir[2],
445 glCallList(basedlist);
450 glDisable(GL_LIGHTING);
451 glDisable(GL_TEXTURE_2D);
452 glDisable(GL_DEPTH_TEST);
454 glShadeModel(GL_FLAT);
456 glMatrixMode(GL_PROJECTION);
458 glOrtho(-0.5,639.5,-0.5,479.5,-1.0,1.0);
459 glMatrixMode(GL_MODELVIEW);
462 glColor3f(1.0,0.0,0.0);
463 glRasterPos2i(10,10);
464 printstring(GLUT_BITMAP_HELVETICA_18,frbuf);
465 glRasterPos2i(350,470);
466 printstring(GLUT_BITMAP_HELVETICA_10,"Teapot V1.2 Written by David Bucciarelli (tech.hmw@plus.it)");
471 reshape(WIDTH,HEIGHT);
478 GLint t = glutGet(GLUT_ELAPSED_TIME);
479 if (t - T0 >= 2000) {
480 GLfloat seconds = (t - T0) / 1000.0;
481 GLfloat fps = Frames / seconds;
482 sprintf(frbuf, "Frame rate: %f", fps);
489 static void inittextures(void)
491 glGenTextures(1,&t1id);
492 glBindTexture(GL_TEXTURE_2D,t1id);
494 glPixelStorei(GL_UNPACK_ALIGNMENT,4);
495 if (!LoadRGBMipmaps("../images/tile.rgb", GL_RGB)) {
496 fprintf(stderr,"Error reading a texture.\n");
500 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
501 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
503 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
504 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
506 glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
508 glGenTextures(1,&t2id);
509 glBindTexture(GL_TEXTURE_2D,t2id);
511 glPixelTransferf(GL_RED_SCALE, 0.75);
512 glPixelTransferf(GL_RED_BIAS, 0.25);
513 glPixelTransferf(GL_GREEN_SCALE, 0.75);
514 glPixelTransferf(GL_GREEN_BIAS, 0.25);
515 glPixelTransferf(GL_BLUE_SCALE, 0.75);
516 glPixelTransferf(GL_BLUE_BIAS, 0.25);
518 if (!LoadRGBMipmaps("../images/bw.rgb", GL_RGB)) {
519 fprintf(stderr,"Error reading a texture.\n");
523 glPixelTransferf(GL_RED_SCALE, 1.0);
524 glPixelTransferf(GL_RED_BIAS, 0.0);
525 glPixelTransferf(GL_GREEN_SCALE, 1.0);
526 glPixelTransferf(GL_GREEN_BIAS, 0.0);
527 glPixelTransferf(GL_BLUE_SCALE, 1.0);
528 glPixelTransferf(GL_BLUE_BIAS, 0.0);
531 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_REPEAT);
532 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_REPEAT);
534 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR_MIPMAP_LINEAR);
535 glTexParameterf(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
537 glTexEnvf(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
540 static void initlight(void)
542 float matamb[4] ={0.5, 0.5, 0.5, 1.0};
543 float matdiff[4]={0.9, 0.2, 0.2, 1.0};
544 float matspec[4]={1.0,1.0,1.0,1.0};
546 float lamb[4] ={1.5, 1.5, 1.5, 1.0};
547 float ldiff[4]={1.0, 1.0, 1.0, 1.0};
548 float lspec[4]={1.0, 1.0, 1.0, 1.0};
550 glLightf(GL_LIGHT0,GL_SPOT_CUTOFF,70.0);
551 glLightf(GL_LIGHT0,GL_SPOT_EXPONENT,20.0);
552 glLightfv(GL_LIGHT0,GL_AMBIENT,lamb);
553 glLightfv(GL_LIGHT0,GL_DIFFUSE,ldiff);
554 glLightfv(GL_LIGHT0,GL_SPECULAR,lspec);
556 glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 15.0);
557 glMaterialfv(GL_FRONT_AND_BACK, GL_DIFFUSE, matdiff);
558 glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, matspec);
559 glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, matamb);
561 glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lamb);
565 static void initdlists(void)
567 GLUquadricObj *lcone,*lbase;
569 GLfloat v0[3]={0.0,0.0,0.0};
570 GLfloat v1[3]={1.0,0.0,0.0};
571 GLfloat v2[3]={0.0,1.0,0.0};
573 findplane(plane,v0,v1,v2);
574 shadowmatrix(baseshadow,plane,lightpos);
576 teapotdlist=glGenLists(1);
577 glNewList(teapotdlist,GL_COMPILE);
578 glRotatef(90.0,1.0,0.0,0.0);
579 glCullFace(GL_FRONT);
580 glBindTexture(GL_TEXTURE_2D,t2id);
581 glutSolidTeapot(0.75);
585 basedlist=glGenLists(1);
586 glNewList(basedlist,GL_COMPILE);
590 lightdlist=glGenLists(1);
591 glNewList(lightdlist,GL_COMPILE);
592 glDisable(GL_LIGHTING);
594 lcone=gluNewQuadric();
595 lbase=gluNewQuadric();
596 glRotatef(45.0,0.0,1.0,0.0);
598 glColor3f(1.0,1.0,1.0);
599 glCullFace(GL_FRONT);
600 gluDisk(lbase,0.0,0.2,12.0,1.0);
603 glColor3f(0.5,0.0,0.0);
604 gluCylinder(lcone,0.2,0.0,0.5,12,1);
606 gluDeleteQuadric(lcone);
607 gluDeleteQuadric(lbase);
609 glEnable(GL_LIGHTING);
613 int main(int ac, char **av)
615 float fogcolor[4]={0.025,0.025,0.025,1.0};
617 fprintf(stderr,"Teapot V1.2\nWritten by David Bucciarelli (tech.hmw@plus.it)\n");
620 if(!SetPriorityClass(GetCurrentProcess(),REALTIME_PRIORITY_CLASS)) {
621 fprintf(stderr,"Error setting the process class.\n");
625 if(!SetThreadPriority(GetCurrentThread(),THREAD_PRIORITY_TIME_CRITICAL)) {
626 fprintf(stderr,"Error setting the process priority.\n");
631 glutInitWindowPosition(0,0);
632 glutInitWindowSize(WIDTH,HEIGHT);
635 glutInitDisplayMode(GLUT_RGB|GLUT_DEPTH|GLUT_DOUBLE);
637 if(!(win=glutCreateWindow("Teapot"))) {
638 fprintf(stderr,"Error, couldn't open window\n");
642 reshape(WIDTH,HEIGHT);
644 glShadeModel(GL_SMOOTH);
645 glEnable(GL_DEPTH_TEST);
646 glEnable(GL_CULL_FACE);
647 glEnable(GL_TEXTURE_2D);
650 glFogi(GL_FOG_MODE,GL_EXP2);
651 glFogfv(GL_FOG_COLOR,fogcolor);
653 glFogf(GL_FOG_DENSITY,0.04);
654 glHint(GL_FOG_HINT,GL_NICEST);
655 glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
664 glClearColor(fogcolor[0],fogcolor[1],fogcolor[2],fogcolor[3]);
666 glutReshapeFunc(reshape);
667 glutDisplayFunc(draw);
668 glutKeyboardFunc(key);
669 glutSpecialFunc(special);