progs/demos/multiarb.c

   1 /* $Id: multiarb.c,v 1.12 2003/05/30 15:30:17 brianp Exp $ */
   2
   3 /*
   4  * GL_ARB_multitexture demo
   5  *
   6  * Command line options:
   7  *    -info      print GL implementation information
   8  *
   9  *
  10  * Brian Paul  November 1998  This program is in the public domain.
  11  * Modified on 12 Feb 2002 for > 2 texture units.
  12  */
  13
  14
  15 #include <math.h>
  16 #include <stdio.h>
  17 #include <stdlib.h>
  18 #include <string.h>
  19 #include <GL/glut.h>
  20
  21 #include "readtex.c"   /* I know, this is a hack. */
  22
  23 #define TEXTURE_1_FILE "../images/girl.rgb"
  24 #define TEXTURE_2_FILE "../images/reflect.rgb"
  25
  26 #define TEX0 1
  27 #define TEX7 8
  28 #define ANIMATE 10
  29 #define QUIT 100
  30
  31 static GLboolean Animate = GL_TRUE;
  32 static GLint NumUnits = 1;
  33 static GLboolean TexEnabled[8];
  34
  35 static GLfloat Drift = 0.0;
  36 static GLfloat drift_increment = 0.005;
  37 static GLfloat Xrot = 20.0, Yrot = 30.0, Zrot = 0.0;
  38
  39
  40
  41 static void Idle( void )
  42 {
  43    if (Animate) {
  44       GLint i;
  45
  46       Drift += drift_increment;
  47       if (Drift >= 1.0)
  48          Drift = 0.0;
  49
  50       for (i = 0; i < NumUnits; i++) {
  51          glActiveTextureARB(GL_TEXTURE0_ARB + i);
  52          glMatrixMode(GL_TEXTURE);
  53          glLoadIdentity();
  54          if (i == 0) {
  55             glTranslatef(Drift, 0.0, 0.0);
  56             glScalef(2, 2, 2);
  57          }
  58          else if (i == 1) {
  59             glTranslatef(0.0, Drift, 0.0);
  60          }
  61          else {
  62             glTranslatef(0.5, 0.5, 0.0);
  63             glRotatef(180.0 * Drift, 0, 0, 1);
  64             glScalef(1.0/i, 1.0/i, 1.0/i);
  65             glTranslatef(-0.5, -0.5, 0.0);
  66          }
  67       }
  68       glMatrixMode(GL_MODELVIEW);
  69
  70       glutPostRedisplay();
  71    }
  72 }
  73
  74
  75 static void DrawObject(void)
  76 {
  77    GLint i;
  78    GLint j;
  79    static const GLfloat   tex_coords[] = {  0.0,  0.0,  1.0,  1.0,  0.0 };
  80    static const GLfloat   vtx_coords[] = { -1.0, -1.0,  1.0,  1.0, -1.0 };
  81
  82    if (!TexEnabled[0] && !TexEnabled[1])
  83       glColor3f(0.1, 0.1, 0.1);  /* add onto this */
  84    else
  85       glColor3f(1, 1, 1);  /* modulate this */
  86
  87    glBegin(GL_QUADS);
  88
  89    /* Toggle between the vector and scalar entry points.  This is done purely
  90     * to hit multiple paths in the driver.
  91     */
  92    if ( Drift > 0.49 ) {
  93       for (j = 0; j < 4; j++ ) {
  94          for (i = 0; i < NumUnits; i++)
  95             glMultiTexCoord2fARB(GL_TEXTURE0_ARB + i,
  96                                  tex_coords[j], tex_coords[j+1]);
  97          glVertex2f( vtx_coords[j], vtx_coords[j+1] );
  98       }
  99    }
 100    else {
 101       for (j = 0; j < 4; j++ ) {
 102          for (i = 0; i < NumUnits; i++)
 103             glMultiTexCoord2fvARB(GL_TEXTURE0_ARB + i, & tex_coords[j]);
 104          glVertex2fv( & vtx_coords[j] );
 105       }
 106    }
 107
 108    glEnd();
 109 }
 110
 111
 112
 113 static void Display( void )
 114 {
 115    static GLint T0 = 0;
 116    static GLint Frames = 0;
 117    GLint t;
 118
 119    glClear( GL_COLOR_BUFFER_BIT );
 120
 121    glPushMatrix();
 122       glRotatef(Xrot, 1.0, 0.0, 0.0);
 123       glRotatef(Yrot, 0.0, 1.0, 0.0);
 124       glRotatef(Zrot, 0.0, 0.0, 1.0);
 125       glScalef(5.0, 5.0, 5.0);
 126       DrawObject();
 127    glPopMatrix();
 128
 129    glutSwapBuffers();
 130
 131    Frames++;
 132
 133    t = glutGet(GLUT_ELAPSED_TIME);
 134    if (t - T0 >= 250) {
 135       GLfloat seconds = (t - T0) / 1000.0;
 136       drift_increment = 2.2 * seconds / Frames;
 137       T0 = t;
 138       Frames = 0;
 139    }
 140 }
 141
 142
 143 static void Reshape( int width, int height )
 144 {
 145    glViewport( 0, 0, width, height );
 146    glMatrixMode( GL_PROJECTION );
 147    glLoadIdentity();
 148    glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 100.0 );
 149    /*glOrtho( -6.0, 6.0, -6.0, 6.0, 10.0, 100.0 );*/
 150    glMatrixMode( GL_MODELVIEW );
 151    glLoadIdentity();
 152    glTranslatef( 0.0, 0.0, -70.0 );
 153 }
 154
 155
 156 static void ModeMenu(int entry)
 157 {
 158    if (entry >= TEX0 && entry <= TEX7) {
 159       /* toggle */
 160       GLint i = entry - TEX0;
 161       TexEnabled[i] = !TexEnabled[i];
 162       glActiveTextureARB(GL_TEXTURE0_ARB + i);
 163       if (TexEnabled[i])
 164          glEnable(GL_TEXTURE_2D);
 165       else
 166          glDisable(GL_TEXTURE_2D);
 167       printf("Enabled: ");
 168       for (i = 0; i < NumUnits; i++)
 169          printf("%d ", (int) TexEnabled[i]);
 170       printf("\n");
 171    }
 172    else if (entry==ANIMATE) {
 173       Animate = !Animate;
 174    }
 175    else if (entry==QUIT) {
 176       exit(0);
 177    }
 178
 179    glutPostRedisplay();
 180 }
 181
 182
 183 static void Key( unsigned char key, int x, int y )
 184 {
 185    (void) x;
 186    (void) y;
 187    switch (key) {
 188       case 27:
 189          exit(0);
 190          break;
 191    }
 192    glutPostRedisplay();
 193 }
 194
 195
 196 static void SpecialKey( int key, int x, int y )
 197 {
 198    float step = 3.0;
 199    (void) x;
 200    (void) y;
 201
 202    switch (key) {
 203       case GLUT_KEY_UP:
 204          Xrot += step;
 205          break;
 206       case GLUT_KEY_DOWN:
 207          Xrot -= step;
 208          break;
 209       case GLUT_KEY_LEFT:
 210          Yrot += step;
 211          break;
 212       case GLUT_KEY_RIGHT:
 213          Yrot -= step;
 214          break;
 215    }
 216    glutPostRedisplay();
 217 }
 218
 219
 220 static void Init( int argc, char *argv[] )
 221 {
 222    GLuint texObj[8];
 223    GLint size, i;
 224
 225    const char *exten = (const char *) glGetString(GL_EXTENSIONS);
 226    if (!strstr(exten, "GL_ARB_multitexture")) {
 227       printf("Sorry, GL_ARB_multitexture not supported by this renderer.\n");
 228       exit(1);
 229    }
 230
 231    glGetIntegerv(GL_MAX_TEXTURE_UNITS_ARB, &NumUnits);
 232    printf("%d texture units supported\n", NumUnits);
 233    if (NumUnits > 8)
 234       NumUnits = 8;
 235
 236    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &size);
 237    printf("%d x %d max texture size\n", size, size);
 238
 239    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 240
 241    for (i = 0; i < NumUnits; i++) {
 242       if (i < 2)
 243          TexEnabled[i] = GL_TRUE;
 244       else
 245          TexEnabled[i] = GL_FALSE;
 246    }
 247
 248    /* allocate two texture objects */
 249    glGenTextures(NumUnits, texObj);
 250
 251    /* setup the texture objects */
 252    for (i = 0; i < NumUnits; i++) {
 253
 254       glActiveTextureARB(GL_TEXTURE0_ARB + i);
 255       glBindTexture(GL_TEXTURE_2D, texObj[i]);
 256
 257       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 258       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 259
 260       if (i == 0) {
 261          if (!LoadRGBMipmaps(TEXTURE_1_FILE, GL_RGB)) {
 262             printf("Error: couldn't load texture image\n");
 263             exit(1);
 264          }
 265       }
 266       else if (i == 1) {
 267          if (!LoadRGBMipmaps(TEXTURE_2_FILE, GL_RGB)) {
 268             printf("Error: couldn't load texture image\n");
 269             exit(1);
 270          }
 271       }
 272       else {
 273          /* checker */
 274          GLubyte image[8][8][3];
 275          GLint i, j;
 276          for (i = 0; i < 8; i++) {
 277             for (j = 0; j < 8; j++) {
 278                if ((i + j) & 1) {
 279                   image[i][j][0] = 50;
 280                   image[i][j][1] = 50;
 281                   image[i][j][2] = 50;
 282                }
 283                else {
 284                   image[i][j][0] = 25;
 285                   image[i][j][1] = 25;
 286                   image[i][j][2] = 25;
 287                }
 288             }
 289          }
 290          glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 8, 8, 0,
 291                       GL_RGB, GL_UNSIGNED_BYTE, (GLvoid *) image);
 292       }
 293
 294       /* Bind texObj[i] to ith texture unit */
 295       if (i < 2)
 296          glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
 297       else
 298          glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_ADD);
 299
 300       if (TexEnabled[i])
 301          glEnable(GL_TEXTURE_2D);
 302    }
 303
 304    glShadeModel(GL_FLAT);
 305    glClearColor(0.3, 0.3, 0.4, 1.0);
 306
 307    if (argc > 1 && strcmp(argv[1], "-info")==0) {
 308       printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 309       printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 310       printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 311       printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 312    }
 313 }
 314
 315
 316 int main( int argc, char *argv[] )
 317 {
 318    GLint i;
 319
 320    glutInit( &argc, argv );
 321    glutInitWindowSize( 300, 300 );
 322    glutInitWindowPosition( 0, 0 );
 323    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
 324    glutCreateWindow(argv[0] );
 325
 326    Init( argc, argv );
 327
 328    glutReshapeFunc( Reshape );
 329    glutKeyboardFunc( Key );
 330    glutSpecialFunc( SpecialKey );
 331    glutDisplayFunc( Display );
 332    glutIdleFunc( Idle );
 333
 334    glutCreateMenu(ModeMenu);
 335
 336    for (i = 0; i < NumUnits; i++) {
 337       char s[100];
 338       sprintf(s, "Toggle Texture %d", i);
 339       glutAddMenuEntry(s, TEX0 + i);
 340    }
 341    glutAddMenuEntry("Toggle Animation", ANIMATE);
 342    glutAddMenuEntry("Quit", QUIT);
 343    glutAttachMenu(GLUT_RIGHT_BUTTON);
 344
 345    glutMainLoop();
 346    return 0;
 347 }