summaryrefslogtreecommitdiff
path: root/progs/demos/multiarb.c
blob: d963985c69de0012520a52de4a8eb2fb5e922a37 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345

/*
 * GL_ARB_multitexture demo
 *
 * Command line options:
 *    -info      print GL implementation information
 *
 *
 * Brian Paul  November 1998  This program is in the public domain.
 * Modified on 12 Feb 2002 for > 2 texture units.
 */


#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glut.h>

#include "readtex.h"

#define TEXTURE_1_FILE "../images/girl.rgb"
#define TEXTURE_2_FILE "../images/reflect.rgb"

#define TEX0 1
#define TEX7 8
#define ANIMATE 10
#define QUIT 100

static GLboolean Animate = GL_TRUE;
static GLint NumUnits = 1;
static GLboolean TexEnabled[8];

static GLfloat Drift = 0.0;
static GLfloat drift_increment = 0.005;
static GLfloat Xrot = 20.0, Yrot = 30.0, Zrot = 0.0;


static void Idle( void )
{
   if (Animate) {
      GLint i;

      Drift += drift_increment;
      if (Drift >= 1.0)
         Drift = 0.0;

      for (i = 0; i < NumUnits; i++) {
         glActiveTextureARB(GL_TEXTURE0_ARB + i);
         glMatrixMode(GL_TEXTURE);
         glLoadIdentity();
         if (i == 0) {
            glTranslatef(Drift, 0.0, 0.0);
            glScalef(2, 2, 1);
         }
         else if (i == 1) {
            glTranslatef(0.0, Drift, 0.0);
         }
         else {
            glTranslatef(0.5, 0.5, 0.0);
            glRotatef(180.0 * Drift, 0, 0, 1);
            glScalef(1.0/i, 1.0/i, 1.0/i);
            glTranslatef(-0.5, -0.5, 0.0);
         }
      }
      glMatrixMode(GL_MODELVIEW);

      glutPostRedisplay();
   }
}


static void DrawObject(void)
{
   GLint i;
   GLint j;
   static const GLfloat   tex_coords[] = {  0.0,  0.0,  1.0,  1.0,  0.0 };
   static const GLfloat   vtx_coords[] = { -1.0, -1.0,  1.0,  1.0, -1.0 };

   if (!TexEnabled[0] && !TexEnabled[1])
      glColor3f(0.1, 0.1, 0.1);  /* add onto this */
   else
      glColor3f(1, 1, 1);  /* modulate this */

   glBegin(GL_QUADS);

   /* Toggle between the vector and scalar entry points.  This is done purely
    * to hit multiple paths in the driver.
    */
   if ( Drift > 0.49 ) {
      for (j = 0; j < 4; j++ ) {
	 for (i = 0; i < NumUnits; i++)
	    glMultiTexCoord2fARB(GL_TEXTURE0_ARB + i, 
				 tex_coords[j], tex_coords[j+1]);
	 glVertex2f( vtx_coords[j], vtx_coords[j+1] );
      }
   }
   else {
      for (j = 0; j < 4; j++ ) {
	 for (i = 0; i < NumUnits; i++)
	    glMultiTexCoord2fvARB(GL_TEXTURE0_ARB + i, & tex_coords[j]);
	 glVertex2fv( & vtx_coords[j] );
      }
   }

   glEnd();
}



static void Display( void )
{
   static GLint T0 = 0;
   static GLint Frames = 0;
   GLint t;

   glClear( GL_COLOR_BUFFER_BIT );

   glPushMatrix();
      glRotatef(Xrot, 1.0, 0.0, 0.0);
      glRotatef(Yrot, 0.0, 1.0, 0.0);
      glRotatef(Zrot, 0.0, 0.0, 1.0);
      glScalef(5.0, 5.0, 5.0);
      DrawObject();
   glPopMatrix();

   glutSwapBuffers();

   Frames++;

   t = glutGet(GLUT_ELAPSED_TIME);
   if (t - T0 >= 250) {
      GLfloat seconds = (t - T0) / 1000.0;
      drift_increment = 2.2 * seconds / Frames;
      T0 = t;
      Frames = 0;
   }
}


static void Reshape( int width, int height )
{
   glViewport( 0, 0, width, height );
   glMatrixMode( GL_PROJECTION );
   glLoadIdentity();
   glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 );
   /*glOrtho( -6.0, 6.0, -6.0, 6.0, 10.0, 100.0 );*/
   glMatrixMode( GL_MODELVIEW );
   glLoadIdentity();
   glTranslatef( 0.0, 0.0, -70.0 );
}


static void ModeMenu(int entry)
{
   if (entry >= TEX0 && entry <= TEX7) {
      /* toggle */
      GLint i = entry - TEX0;
      TexEnabled[i] = !TexEnabled[i];
      glActiveTextureARB(GL_TEXTURE0_ARB + i);
      if (TexEnabled[i])
         glEnable(GL_TEXTURE_2D);
      else
         glDisable(GL_TEXTURE_2D);
      printf("Enabled: ");
      for (i = 0; i < NumUnits; i++)
         printf("%d ", (int) TexEnabled[i]);
      printf("\n");
   }
   else if (entry==ANIMATE) {
      Animate = !Animate;
   }
   else if (entry==QUIT) {
      exit(0);
   }

   glutPostRedisplay();
}


static void Key( unsigned char key, int x, int y )
{
   (void) x;
   (void) y;
   switch (key) {
      case 27:
         exit(0);
         break;
   }
   glutPostRedisplay();
}


static void SpecialKey( int key, int x, int y )
{
   float step = 3.0;
   (void) x;
   (void) y;

   switch (key) {
      case GLUT_KEY_UP:
         Xrot += step;
         break;
      case GLUT_KEY_DOWN:
         Xrot -= step;
         break;
      case GLUT_KEY_LEFT:
         Yrot += step;
         break;
      case GLUT_KEY_RIGHT:
         Yrot -= step;
         break;
   }
   glutPostRedisplay();
}


static void Init( int argc, char *argv[] )
{
   GLuint texObj[8];
   GLint size, i;

   const char *exten = (const char *) glGetString(GL_EXTENSIONS);
   if (!strstr(exten, "GL_ARB_multitexture")) {
      printf("Sorry, GL_ARB_multitexture not supported by this renderer.\n");
      exit(1);
   }

   glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &NumUnits);
   printf("%d texture units supported\n", NumUnits);
   if (NumUnits > 8)
      NumUnits = 8;

   glGetIntegerv(GL_MAX_TEXTURE_SIZE, &size);
   printf("%d x %d max texture size\n", size, size);

   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

   for (i = 0; i < NumUnits; i++) {
      if (i < 2)
         TexEnabled[i] = GL_TRUE;
      else
         TexEnabled[i] = GL_FALSE;
   }

   /* allocate two texture objects */
   glGenTextures(NumUnits, texObj);

   /* setup the texture objects */
   for (i = 0; i < NumUnits; i++) {

      glActiveTextureARB(GL_TEXTURE0_ARB + i);
      glBindTexture(GL_TEXTURE_2D, texObj[i]);

      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
      glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);

      if (i == 0) {
         if (!LoadRGBMipmaps(TEXTURE_1_FILE, GL_RGB)) {
            printf("Error: couldn't load texture image\n");
            exit(1);
         }
      }
      else if (i == 1) {
         if (!LoadRGBMipmaps(TEXTURE_2_FILE, GL_RGB)) {
            printf("Error: couldn't load texture image\n");
            exit(1);
         }
      }
      else {
         /* checker */
         GLubyte image[8][8][3];
         GLint i, j;
         for (i = 0; i < 8; i++) {
            for (j = 0; j < 8; j++) {
               if ((i + j) & 1) {
                  image[i][j][0] = 50;
                  image[i][j][1] = 50;
                  image[i][j][2] = 50;
               }
               else {
                  image[i][j][0] = 25;
                  image[i][j][1] = 25;
                  image[i][j][2] = 25;
               }
            }
         }
         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 8, 8, 0,
                      GL_RGB, GL_UNSIGNED_BYTE, (GLvoid *) image);
      }

      /* Bind texObj[i] to ith texture unit */
      if (i < 2)
         glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
      else
         glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_ADD);

      if (TexEnabled[i])
         glEnable(GL_TEXTURE_2D);
   }

   glShadeModel(GL_FLAT);
   glClearColor(0.3, 0.3, 0.4, 1.0);

   if (argc > 1 && strcmp(argv[1], "-info")==0) {
      printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
      printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
      printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
      printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
   }
}


int main( int argc, char *argv[] )
{
   GLint i;

   glutInit( &argc, argv );
   glutInitWindowSize( 300, 300 );
   glutInitWindowPosition( 0, 0 );
   glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
   glutCreateWindow(argv[0] );

   Init( argc, argv );

   glutReshapeFunc( Reshape );
   glutKeyboardFunc( Key );
   glutSpecialFunc( SpecialKey );
   glutDisplayFunc( Display );
   glutIdleFunc( Idle );

   glutCreateMenu(ModeMenu);

   for (i = 0; i < NumUnits; i++) {
      char s[100];
      sprintf(s, "Toggle Texture %d", i);
      glutAddMenuEntry(s, TEX0 + i);
   }
   glutAddMenuEntry("Toggle Animation", ANIMATE);
   glutAddMenuEntry("Quit", QUIT);
   glutAttachMenu(GLUT_RIGHT_BUTTON);

   glutMainLoop();
   return 0;
}