progs/demos/osdemo.c

   1 /* $Id: osdemo.c,v 1.3 2000/03/06 23:56:21 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 OSMESA_OCCLUSION_TEST_RESULT_HP
  79    {
  80       GLboolean bRet;
  81       OSMesaGetBooleanv(OSMESA_OCCLUSION_TEST_RESULT_HP,&bRet);
  82       glDepthMask(GL_FALSE);
  83       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
  84
  85       glPushMatrix();
  86       glTranslatef(0.75, 0.0, -1.0);
  87       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
  88       glutSolidSphere(1.0, 20, 20);
  89       glPopMatrix();
  90
  91       OSMesaGetBooleanv(OSMESA_OCCLUSION_TEST_RESULT_HP,&bRet);
  92       printf("Occlusion test 1 (result should be 1): %d\n",bRet);
  93
  94       glDepthMask(GL_TRUE);
  95       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
  96    }
  97 #endif
  98
  99    glPushMatrix();
 100    glTranslatef(0.75, 0.0, -1.0);
 101    glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 102    glutSolidSphere(1.0, 20, 20);
 103    glPopMatrix();
 104
 105 #ifdef OSMESA_OCCLUSION_TEST_RESULT_HP
 106    {
 107       GLboolean bRet;
 108
 109       OSMesaGetBooleanv(OSMESA_OCCLUSION_TEST_RESULT_HP,&bRet);
 110       glDepthMask(GL_FALSE);
 111       glColorMask(GL_FALSE,GL_FALSE,GL_FALSE,GL_FALSE);
 112
 113       /* draw a sphere inside the previous sphere */
 114       glPushMatrix();
 115       glTranslatef(0.75, 0.0, -1.0);
 116       glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
 117       glutSolidSphere(0.5, 20, 20);
 118       glPopMatrix();
 119
 120       OSMesaGetBooleanv(OSMESA_OCCLUSION_TEST_RESULT_HP,&bRet);
 121       printf("Occlusion test 2 (result should be 0): %d\n",bRet);
 122
 123       glDepthMask(GL_TRUE);
 124       glColorMask(GL_TRUE,GL_TRUE,GL_TRUE,GL_TRUE);
 125    }
 126 #endif
 127
 128    glPopMatrix();
 129 }
 130
 131
 132
 133 static void
 134 write_targa(const char *filename, const GLubyte *buffer, int width, int height)
 135 {
 136    FILE *f = fopen( filename, "w" );
 137    if (f) {
 138       int i, x, y;
 139       const GLubyte *ptr = buffer;
 140       printf ("osdemo, writing tga file \n");
 141       fputc (0x00, f);  /* ID Length, 0 => No ID        */
 142       fputc (0x00, f);  /* Color Map Type, 0 => No color map included   */
 143       fputc (0x02, f);  /* Image Type, 2 => Uncompressed, True-color Image */
 144       fputc (0x00, f);  /* Next five bytes are about the color map entries */
 145       fputc (0x00, f);  /* 2 bytes Index, 2 bytes length, 1 byte size */
 146       fputc (0x00, f);
 147       fputc (0x00, f);
 148       fputc (0x00, f);
 149       fputc (0x00, f);  /* X-origin of Image    */
 150       fputc (0x00, f);
 151       fputc (0x00, f);  /* Y-origin of Image    */
 152       fputc (0x00, f);
 153       fputc (WIDTH & 0xff, f);      /* Image Width      */
 154       fputc ((WIDTH>>8) & 0xff, f);
 155       fputc (HEIGHT & 0xff, f);     /* Image Height     */
 156       fputc ((HEIGHT>>8) & 0xff, f);
 157       fputc (0x18, f);          /* Pixel Depth, 0x18 => 24 Bits */
 158       fputc (0x20, f);          /* Image Descriptor     */
 159       fclose(f);
 160       f = fopen( filename, "ab" );  /* reopen in binary append mode */
 161       for (y=height-1; y>=0; y--) {
 162          for (x=0; x<width; x++) {
 163             i = (y*width + x) * 4;
 164             fputc(ptr[i+2], f); /* write blue */
 165             fputc(ptr[i+1], f); /* write green */
 166             fputc(ptr[i], f);   /* write red */
 167          }
 168       }
 169    }
 170 }
 171
 172
 173 static void
 174 write_ppm(const char *filename, const GLubyte *buffer, int width, int height)
 175 {
 176    const int binary = 0;
 177    FILE *f = fopen( filename, "w" );
 178    if (f) {
 179       int i, x, y;
 180       const GLubyte *ptr = buffer;
 181       if (binary) {
 182          fprintf(f,"P6\n");
 183          fprintf(f,"# ppm-file created by osdemo.c\n");
 184          fprintf(f,"%i %i\n", width,height);
 185          fprintf(f,"255\n");
 186          fclose(f);
 187          f = fopen( filename, "ab" );  /* reopen in binary append mode */
 188          for (y=height-1; y>=0; y--) {
 189             for (x=0; x<width; x++) {
 190                i = (y*width + x) * 4;
 191                fputc(ptr[i], f);   /* write red */
 192                fputc(ptr[i+1], f); /* write green */
 193                fputc(ptr[i+2], f); /* write blue */
 194             }
 195          }
 196       }
 197       else {
 198          /*ASCII*/
 199          int counter = 0;
 200          fprintf(f,"P3\n");
 201          fprintf(f,"# ascii ppm file created by osdemo.c\n");
 202          fprintf(f,"%i %i\n", width, height);
 203          fprintf(f,"255\n");
 204          for (y=height-1; y>=0; y--) {
 205             for (x=0; x<width; x++) {
 206                i = (y*width + x) * 4;
 207                fprintf(f, " %3d %3d %3d", ptr[i], ptr[i+1], ptr[i+2]);
 208                counter++;
 209                if (counter % 5 == 0)
 210                   fprintf(f, "\n");
 211             }
 212          }
 213       }
 214       fclose(f);
 215    }
 216 }
 217
 218
 219
 220 int main( int argc, char *argv[] )
 221 {
 222    /* Create an RGBA-mode context */
 223    OSMesaContext ctx = OSMesaCreateContext( GL_RGBA, NULL );
 224
 225    /* Allocate the image buffer */
 226    void *buffer = malloc( WIDTH * HEIGHT * 4 );
 227
 228    /* Bind the buffer to the context and make it current */
 229    OSMesaMakeCurrent( ctx, buffer, GL_UNSIGNED_BYTE, WIDTH, HEIGHT );
 230
 231    render_image();
 232
 233    if (argc>1) {
 234 #ifdef SAVE_TARGA
 235       write_targa(argv[1], buffer, WIDTH, HEIGHT);
 236 #else
 237       write_ppm(argv[1], buffer, WIDTH, HEIGHT);
 238 #endif
 239    }
 240    else {
 241       printf("Specify a filename if you want to make an image file\n");
 242    }
 243
 244    printf("all done\n");
 245
 246    /* free the image buffer */
 247    free( buffer );
 248
 249    /* destroy the context */
 250    OSMesaDestroyContext( ctx );
 251
 252    return 0;
 253 }