progs/demos/osdemo.c

   1
   2 /*
   3  * Demo of off-screen Mesa rendering
   4  *
   5  * See Mesa/include/GL/osmesa.h for documentation of the OSMesa functions.
   6  *
   7  * If you want to render BIG images you'll probably have to increase
   8  * MAX_WIDTH and MAX_HEIGHT in src/config.h.
   9  *
  10  * This program is in the public domain.
  11  *
  12  * Brian Paul
  13  *
  14  * PPM output provided by Joerg Schmalzl.
  15  * ASCII PPM output added by Brian Paul.
  16  *
  17  * Usage: osdemo [-perf] [filename]
  18  *
  19  * -perf: Redraws the image 1000 times, displaying the FPS every 5 secs.
  20  * filename: file to store the TGA or PPM output
  21  */
  22
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include "GL/osmesa.h"
  28 #include "GL/glut.h"
  29
  30
  31 #define SAVE_TARGA
  32
  33
  34 #define WIDTH 400
  35 #define HEIGHT 400
  36
  37 static GLint T0 = 0;
  38 static GLint Frames = 0;
  39 static int perf = 0;
  40
  41 static void render_image( void )
  42 {
  43    GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 };
  44    GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 };
  45    GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 };
  46    GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };
  47    GLfloat red_mat[]   = { 1.0, 0.2, 0.2, 1.0 };
  48    GLfloat green_mat[] = { 0.2, 1.0, 0.2, 1.0 };
  49    GLfloat blue_mat[]  = { 0.2, 0.2, 1.0, 1.0 };
  50
  51
  52    glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
  53    glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
  54    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
  55    glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  56
  57    glEnable(GL_LIGHTING);
  58    glEnable(GL_LIGHT0);
  59    glEnable(GL_DEPTH_TEST);
  60
  61    glMatrixMode(GL_PROJECTION);
  62    glLoadIdentity();
  63    glOrtho(-2.5, 2.5, -2.5, 2.5, -10.0, 10.0);
  64    glMatrixMode(GL_MODELVIEW);
  65
  66    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
  67
  68    glPushMatrix();
  69    glRotatef(20.0, 1.0, 0.0, 0.0);
  70
  71    glPushMatrix();
  72    glTranslatef(-0.75, 0.5, 0.0);
  73    glRotatef(90.0, 1.0, 0.0, 0.0);
  74    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, red_mat );
  75    glutSolidTorus(0.275, 0.85, 20, 20);
  76    glPopMatrix();
  77
  78    glPushMatrix();
  79    glTranslatef(-0.75, -0.5, 0.0);
  80    glRotatef(270.0, 1.0, 0.0, 0.0);
  81    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, green_mat );
  82    glutSolidCone(1.0, 2.0, 16, 1);
  83    glPopMatrix();
  84
  85 #ifdef GL_HP_occlusion_test
  86    if (perf == 0) {
  87       GLboolean bRet;
  88       glDepthMask(GL_FALSE);
  89       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
  90       glEnable(GL_OCCLUSION_TEST_HP);
  91       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
  92
  93       glPushMatrix();
  94       glTranslatef(0.75, 0.0, -1.0);
  95       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
  96       glutSolidSphere(1.0, 20, 20);
  97       glPopMatrix();
  98
  99       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
 100       printf("Occlusion test 1 (result should be 1): %d\n",bRet);
 101
 102       glDepthMask(GL_TRUE);
 103       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
 104       glDisable(GL_OCCLUSION_TEST_HP);
 105    }
 106 #endif
 107
 108    glPushMatrix();
 109    glTranslatef(0.75, 0.0, -1.0);
 110    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 111    glutSolidSphere(1.0, 20, 20);
 112    glPopMatrix();
 113
 114 #ifdef GL_HP_occlusion_test
 115    if (perf == 0){
 116       GLboolean bRet;
 117
 118       glDepthMask(GL_FALSE);
 119       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
 120       glEnable(GL_OCCLUSION_TEST_HP);
 121       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
 122
 123       /* draw a sphere inside the previous sphere */
 124       glPushMatrix();
 125       glTranslatef(0.75, 0.0, -1.0);
 126       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 127       glutSolidSphere(0.5, 20, 20);
 128       glPopMatrix();
 129
 130       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
 131       printf("Occlusion test 2 (result should be 0): %d\n",bRet);
 132
 133       glDepthMask(GL_TRUE);
 134       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
 135       glDisable(GL_OCCLUSION_TEST_HP);
 136    }
 137 #endif
 138
 139    glPopMatrix();
 140
 141    /* This is very important!!!
 142     * Make sure buffered commands are finished!!!
 143     */
 144    glFinish();
 145
 146    Frames++;
 147    if (perf) {
 148      GLint t = glutGet(GLUT_ELAPSED_TIME);
 149      if (t - T0 >= 5000) {
 150         GLfloat seconds = (t - T0) / 1000.0;
 151         GLfloat fps = Frames / seconds;
 152         printf("%d frames in %6.3f seconds = %6.3f FPS\n", Frames, seconds, fps);
 153         T0 = t;
 154         Frames = 0;
 155      }
 156    }
 157 }
 158
 159
 160 #ifdef SAVE_TARGA
 161
 162 static void
 163 write_targa(const char *filename, const GLubyte *buffer, int width, int height)
 164 {
 165    FILE *f = fopen( filename, "w" );
 166    if (f) {
 167       int i, x, y;
 168       const GLubyte *ptr = buffer;
 169       printf ("osdemo, writing tga file \n");
 170       fputc (0x00, f);  /* ID Length, 0 => No ID        */
 171       fputc (0x00, f);  /* Color Map Type, 0 => No color map included   */
 172       fputc (0x02, f);  /* Image Type, 2 => Uncompressed, True-color Image */
 173       fputc (0x00, f);  /* Next five bytes are about the color map entries */
 174       fputc (0x00, f);  /* 2 bytes Index, 2 bytes length, 1 byte size */
 175       fputc (0x00, f);
 176       fputc (0x00, f);
 177       fputc (0x00, f);
 178       fputc (0x00, f);  /* X-origin of Image    */
 179       fputc (0x00, f);
 180       fputc (0x00, f);  /* Y-origin of Image    */
 181       fputc (0x00, f);
 182       fputc (WIDTH & 0xff, f);      /* Image Width      */
 183       fputc ((WIDTH>>8) & 0xff, f);
 184       fputc (HEIGHT & 0xff, f);     /* Image Height     */
 185       fputc ((HEIGHT>>8) & 0xff, f);
 186       fputc (0x18, f);          /* Pixel Depth, 0x18 => 24 Bits */
 187       fputc (0x20, f);          /* Image Descriptor     */
 188       fclose(f);
 189       f = fopen( filename, "ab" );  /* reopen in binary append mode */
 190       for (y=height-1; y>=0; y--) {
 191          for (x=0; x<width; x++) {
 192             i = (y*width + x) * 4;
 193             fputc(ptr[i+2], f); /* write blue */
 194             fputc(ptr[i+1], f); /* write green */
 195             fputc(ptr[i], f);   /* write red */
 196          }
 197       }
 198    }
 199 }
 200
 201 #else
 202
 203 static void
 204 write_ppm(const char *filename, const GLubyte *buffer, int width, int height)
 205 {
 206    const int binary = 0;
 207    FILE *f = fopen( filename, "w" );
 208    if (f) {
 209       int i, x, y;
 210       const GLubyte *ptr = buffer;
 211       if (binary) {
 212          fprintf(f,"P6\n");
 213          fprintf(f,"# ppm-file created by osdemo.c\n");
 214          fprintf(f,"%i %i\n", width,height);
 215          fprintf(f,"255\n");
 216          fclose(f);
 217          f = fopen( filename, "ab" );  /* reopen in binary append mode */
 218          for (y=height-1; y>=0; y--) {
 219             for (x=0; x<width; x++) {
 220                i = (y*width + x) * 4;
 221                fputc(ptr[i], f);   /* write red */
 222                fputc(ptr[i+1], f); /* write green */
 223                fputc(ptr[i+2], f); /* write blue */
 224             }
 225          }
 226       }
 227       else {
 228          /*ASCII*/
 229          int counter = 0;
 230          fprintf(f,"P3\n");
 231          fprintf(f,"# ascii ppm file created by osdemo.c\n");
 232          fprintf(f,"%i %i\n", width, height);
 233          fprintf(f,"255\n");
 234          for (y=height-1; y>=0; y--) {
 235             for (x=0; x<width; x++) {
 236                i = (y*width + x) * 4;
 237                fprintf(f, " %3d %3d %3d", ptr[i], ptr[i+1], ptr[i+2]);
 238                counter++;
 239                if (counter % 5 == 0)
 240                   fprintf(f, "\n");
 241             }
 242          }
 243       }
 244       fclose(f);
 245    }
 246 }
 247
 248 #endif
 249
 250
 251
 252 int main( int argc, char *argv[] )
 253 {
 254    void *buffer;
 255    int i;
 256    char *filename = NULL;
 257
 258    /* Create an RGBA-mode context */
 259 #if OSMESA_MAJOR_VERSION * 100 + OSMESA_MINOR_VERSION >= 305
 260    /* specify Z, stencil, accum sizes */
 261    OSMesaContext ctx = OSMesaCreateContextExt( OSMESA_RGBA, 16, 0, 0, NULL );
 262 #else
 263    OSMesaContext ctx = OSMesaCreateContext( OSMESA_RGBA, NULL );
 264 #endif
 265    if (!ctx) {
 266       printf("OSMesaCreateContext failed!\n");
 267       return 0;
 268    }
 269
 270    for ( i=1; i<argc; i++ ) {
 271       if (argv[i][0] != '-') filename = argv[i];
 272       if (strcmp(argv[i], "-perf")==0) perf = 1;
 273    }
 274
 275    /* Allocate the image buffer */
 276    buffer = malloc( WIDTH * HEIGHT * 4 * sizeof(GLubyte) );
 277    if (!buffer) {
 278       printf("Alloc image buffer failed!\n");
 279       return 0;
 280    }
 281
 282    /* Bind the buffer to the context and make it current */
 283    if (!OSMesaMakeCurrent( ctx, buffer, GL_UNSIGNED_BYTE, WIDTH, HEIGHT )) {
 284       printf("OSMesaMakeCurrent failed!\n");
 285       return 0;
 286    }
 287
 288
 289    {
 290       int z, s, a;
 291       glGetIntegerv(GL_DEPTH_BITS, &z);
 292       glGetIntegerv(GL_STENCIL_BITS, &s);
 293       glGetIntegerv(GL_ACCUM_RED_BITS, &a);
 294       printf("Depth=%d Stencil=%d Accum=%d\n", z, s, a);
 295    }
 296
 297    render_image();
 298    if (perf)
 299       for(i=0; i< 1000; i++)
 300          render_image();
 301
 302    if (filename != NULL) {
 303 #ifdef SAVE_TARGA
 304       write_targa(filename, buffer, WIDTH, HEIGHT);
 305 #else
 306       write_ppm(filename, buffer, WIDTH, HEIGHT);
 307 #endif
 308    }
 309    else {
 310       printf("Specify a filename if you want to make an image file\n");
 311    }
 312
 313    printf("all done\n");
 314
 315    /* free the image buffer */
 316    free( buffer );
 317
 318    /* destroy the context */
 319    OSMesaDestroyContext( ctx );
 320
 321    return 0;
 322 }