progs/demos/osdemo.c

   1 /* $Id: osdemo.c,v 1.5 2000/09/08 16:42:06 brianp Exp $ */
   2
   3 /*
   4  * Demo of off-screen Mesa rendering
   5  *
   6  * See Mesa/include/GL/osmesa.h for documentation of the OSMesa functions.
   7  *
   8  * If you want to render BIG images you'll probably have to increase
   9  * MAX_WIDTH and MAX_HEIGHT in src/config.h.
  10  *
  11  * This program is in the public domain.
  12  *
  13  * Brian Paul
  14  *
  15  * PPM output provided by Joerg Schmalzl.
  16  * ASCII PPM output added by Brian Paul.
  17  */
  18
  19
  20 #include <stdio.h>
  21 #include <stdlib.h>
  22 #include "GL/osmesa.h"
  23 #include "GL/glut.h"
  24
  25
  26 #define SAVE_TARGA
  27
  28
  29 #define WIDTH 400
  30 #define HEIGHT 400
  31
  32
  33
  34 static void render_image( void )
  35 {
  36    GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 };
  37    GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 };
  38    GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 };
  39    GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };
  40    GLfloat red_mat[]   = { 1.0, 0.2, 0.2, 1.0 };
  41    GLfloat green_mat[] = { 0.2, 1.0, 0.2, 1.0 };
  42    GLfloat blue_mat[]  = { 0.2, 0.2, 1.0, 1.0 };
  43
  44
  45    glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
  46    glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
  47    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
  48    glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  49
  50    glEnable(GL_LIGHTING);
  51    glEnable(GL_LIGHT0);
  52    glEnable(GL_DEPTH_TEST);
  53
  54    glMatrixMode(GL_PROJECTION);
  55    glLoadIdentity();
  56    glOrtho(-2.5, 2.5, -2.5, 2.5, -10.0, 10.0);
  57    glMatrixMode(GL_MODELVIEW);
  58
  59    glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
  60
  61    glPushMatrix();
  62    glRotatef(20.0, 1.0, 0.0, 0.0);
  63
  64    glPushMatrix();
  65    glTranslatef(-0.75, 0.5, 0.0);
  66    glRotatef(90.0, 1.0, 0.0, 0.0);
  67    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, red_mat );
  68    glutSolidTorus(0.275, 0.85, 20, 20);
  69    glPopMatrix();
  70
  71    glPushMatrix();
  72    glTranslatef(-0.75, -0.5, 0.0);
  73    glRotatef(270.0, 1.0, 0.0, 0.0);
  74    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, green_mat );
  75    glutSolidCone(1.0, 2.0, 16, 1);
  76    glPopMatrix();
  77
  78 #ifdef GL_HP_occlusion_test
  79    {
  80       GLboolean bRet;
  81       glDepthMask(GL_FALSE);
  82       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
  83       glEnable(GL_OCCLUSION_TEST_HP);
  84       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
  85
  86       glPushMatrix();
  87       glTranslatef(0.75, 0.0, -1.0);
  88       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
  89       glutSolidSphere(1.0, 20, 20);
  90       glPopMatrix();
  91
  92       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
  93       printf("Occlusion test 1 (result should be 1): %d\n",bRet);
  94
  95       glDepthMask(GL_TRUE);
  96       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
  97       glDisable(GL_OCCLUSION_TEST_HP);
  98    }
  99 #endif
 100
 101    glPushMatrix();
 102    glTranslatef(0.75, 0.0, -1.0);
 103    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 104    glutSolidSphere(1.0, 20, 20);
 105    glPopMatrix();
 106
 107 #ifdef GL_HP_occlusion_test
 108    {
 109       GLboolean bRet;
 110
 111       glDepthMask(GL_FALSE);
 112       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
 113       glEnable(GL_OCCLUSION_TEST_HP);
 114       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
 115
 116       /* draw a sphere inside the previous sphere */
 117       glPushMatrix();
 118       glTranslatef(0.75, 0.0, -1.0);
 119       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 120       glutSolidSphere(0.5, 20, 20);
 121       glPopMatrix();
 122
 123       glGetBooleanv(GL_OCCLUSION_TEST_RESULT_HP,&bRet);
 124       printf("Occlusion test 2 (result should be 0): %d\n",bRet);
 125
 126       glDepthMask(GL_TRUE);
 127       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
 128       glDisable(GL_OCCLUSION_TEST_HP);
 129    }
 130 #endif
 131
 132    glPopMatrix();
 133 }
 134
 135
 136
 137 static void
 138 write_targa(const char *filename, const GLubyte *buffer, int width, int height)
 139 {
 140    FILE *f = fopen( filename, "w" );
 141    if (f) {
 142       int i, x, y;
 143       const GLubyte *ptr = buffer;
 144       printf ("osdemo, writing tga file \n");
 145       fputc (0x00, f);  /* ID Length, 0 => No ID        */
 146       fputc (0x00, f);  /* Color Map Type, 0 => No color map included   */
 147       fputc (0x02, f);  /* Image Type, 2 => Uncompressed, True-color Image */
 148       fputc (0x00, f);  /* Next five bytes are about the color map entries */
 149       fputc (0x00, f);  /* 2 bytes Index, 2 bytes length, 1 byte size */
 150       fputc (0x00, f);
 151       fputc (0x00, f);
 152       fputc (0x00, f);
 153       fputc (0x00, f);  /* X-origin of Image    */
 154       fputc (0x00, f);
 155       fputc (0x00, f);  /* Y-origin of Image    */
 156       fputc (0x00, f);
 157       fputc (WIDTH & 0xff, f);      /* Image Width      */
 158       fputc ((WIDTH>>8) & 0xff, f);
 159       fputc (HEIGHT & 0xff, f);     /* Image Height     */
 160       fputc ((HEIGHT>>8) & 0xff, f);
 161       fputc (0x18, f);          /* Pixel Depth, 0x18 => 24 Bits */
 162       fputc (0x20, f);          /* Image Descriptor     */
 163       fclose(f);
 164       f = fopen( filename, "ab" );  /* reopen in binary append mode */
 165       for (y=height-1; y>=0; y--) {
 166          for (x=0; x<width; x++) {
 167             i = (y*width + x) * 4;
 168             fputc(ptr[i+2], f); /* write blue */
 169             fputc(ptr[i+1], f); /* write green */
 170             fputc(ptr[i], f);   /* write red */
 171          }
 172       }
 173    }
 174 }
 175
 176
 177 static void
 178 write_ppm(const char *filename, const GLubyte *buffer, int width, int height)
 179 {
 180    const int binary = 0;
 181    FILE *f = fopen( filename, "w" );
 182    if (f) {
 183       int i, x, y;
 184       const GLubyte *ptr = buffer;
 185       if (binary) {
 186          fprintf(f,"P6\n");
 187          fprintf(f,"# ppm-file created by osdemo.c\n");
 188          fprintf(f,"%i %i\n", width,height);
 189          fprintf(f,"255\n");
 190          fclose(f);
 191          f = fopen( filename, "ab" );  /* reopen in binary append mode */
 192          for (y=height-1; y>=0; y--) {
 193             for (x=0; x<width; x++) {
 194                i = (y*width + x) * 4;
 195                fputc(ptr[i], f);   /* write red */
 196                fputc(ptr[i+1], f); /* write green */
 197                fputc(ptr[i+2], f); /* write blue */
 198             }
 199          }
 200       }
 201       else {
 202          /*ASCII*/
 203          int counter = 0;
 204          fprintf(f,"P3\n");
 205          fprintf(f,"# ascii ppm file created by osdemo.c\n");
 206          fprintf(f,"%i %i\n", width, height);
 207          fprintf(f,"255\n");
 208          for (y=height-1; y>=0; y--) {
 209             for (x=0; x<width; x++) {
 210                i = (y*width + x) * 4;
 211                fprintf(f, " %3d %3d %3d", ptr[i], ptr[i+1], ptr[i+2]);
 212                counter++;
 213                if (counter % 5 == 0)
 214                   fprintf(f, "\n");
 215             }
 216          }
 217       }
 218       fclose(f);
 219    }
 220 }
 221
 222
 223
 224 int main( int argc, char *argv[] )
 225 {
 226    void *buffer;
 227
 228    /* Create an RGBA-mode context */
 229 #if OSMESA_MAJOR_VERSION * 100 + OSMESA_MINOR_VERSION >= 305
 230    /* specify Z, stencil, accum sizes */
 231    OSMesaContext ctx = OSMesaCreateContextExt( GL_RGBA, 16, 0, 0, NULL );
 232 #else
 233    OSMesaContext ctx = OSMesaCreateContext( GL_RGBA, NULL );
 234 #endif
 235    if (!ctx) {
 236       printf("OSMesaCreateContext failed!\n");
 237       return 0;
 238    }
 239
 240    /* Allocate the image buffer */
 241    buffer = malloc( WIDTH * HEIGHT * 4 );
 242    if (!buffer) {
 243       printf("Alloc image buffer failed!\n");
 244       return 0;
 245    }
 246
 247    /* Bind the buffer to the context and make it current */
 248    OSMesaMakeCurrent( ctx, buffer, GL_UNSIGNED_BYTE, WIDTH, HEIGHT );
 249
 250    {
 251       int z, s, a;
 252       glGetIntegerv(GL_DEPTH_BITS, &z);
 253       glGetIntegerv(GL_STENCIL_BITS, &s);
 254       glGetIntegerv(GL_ACCUM_RED_BITS, &a);
 255       printf("%d %d %d\n", z, s, a);
 256    }
 257
 258    render_image();
 259
 260    if (argc>1) {
 261 #ifdef SAVE_TARGA
 262       write_targa(argv[1], buffer, WIDTH, HEIGHT);
 263 #else
 264       write_ppm(argv[1], buffer, WIDTH, HEIGHT);
 265 #endif
 266    }
 267    else {
 268       printf("Specify a filename if you want to make an image file\n");
 269    }
 270
 271    printf("all done\n");
 272
 273    /* free the image buffer */
 274    free( buffer );
 275
 276    /* destroy the context */
 277    OSMesaDestroyContext( ctx );
 278
 279    return 0;
 280 }