Initial revision

progs/demos/osdemo.c

@@ -0,0 +1,169 @@
+/* $Id: osdemo.c,v 1.1 1999/08/19 00:55:40 jtg Exp $ */
+
+/*
+ * Demo of off-screen Mesa rendering
+ *
+ * See Mesa/include/GL/osmesa.h for documentation of the OSMesa functions.
+ *
+ * If you want to render BIG images you'll probably have to increase
+ * MAX_WIDTH and MAX_HEIGHT in src/config.h.
+ *
+ * This program is in the public domain.
+ *
+ * Brian Paul
+ *
+ * PPM output provided by Joerg Schmalzl.
+ * ASCII PPM output added by Brian Paul.
+ */
+
+
+/*
+ * $Log: osdemo.c,v $
+ * Revision 1.1  1999/08/19 00:55:40  jtg
+ * Initial revision
+ *
+ * Revision 3.0  1998/02/14 18:42:29  brianp
+ * initial rev
+ *
+ */
+
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "GL/osmesa.h"
+#include "GL/glut.h"
+
+
+
+#define WIDTH 400
+#define HEIGHT 400
+
+
+
+static void render_image( void )
+{
+   GLfloat light_ambient[] = { 0.0, 0.0, 0.0, 1.0 };
+   GLfloat light_diffuse[] = { 1.0, 1.0, 1.0, 1.0 };
+   GLfloat light_specular[] = { 1.0, 1.0, 1.0, 1.0 };
+   GLfloat light_position[] = { 1.0, 1.0, 1.0, 0.0 };
+   GLfloat red_mat[]   = { 1.0, 0.2, 0.2, 1.0 };
+   GLfloat green_mat[] = { 0.2, 1.0, 0.2, 1.0 };
+   GLfloat blue_mat[]  = { 0.2, 0.2, 1.0, 1.0 };
+
+
+   glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
+   glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
+   glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
+   glLightfv(GL_LIGHT0, GL_POSITION, light_position);
+    
+   glEnable(GL_LIGHTING);
+   glEnable(GL_LIGHT0);
+   glEnable(GL_DEPTH_TEST);
+
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glOrtho(-2.5, 2.5, -2.5, 2.5, -10.0, 10.0);
+   glMatrixMode(GL_MODELVIEW);
+
+   glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
+
+   glPushMatrix();
+   glRotatef(20.0, 1.0, 0.0, 0.0);
+
+   glPushMatrix();
+   glTranslatef(-0.75, 0.5, 0.0); 
+   glRotatef(90.0, 1.0, 0.0, 0.0);
+   glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, red_mat );
+   glutSolidTorus(0.275, 0.85, 20, 20);
+   glPopMatrix();
+
+   glPushMatrix();
+   glTranslatef(-0.75, -0.5, 0.0); 
+   glRotatef(270.0, 1.0, 0.0, 0.0);
+   glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, green_mat );
+   glutSolidCone(1.0, 2.0, 16, 1);
+   glPopMatrix();
+
+   glPushMatrix();
+   glTranslatef(0.75, 0.0, -1.0); 
+   glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, blue_mat );
+   glutSolidSphere(1.0, 20, 20);
+   glPopMatrix();
+
+   glPopMatrix();
+}
+
+
+
+int main( int argc, char *argv[] )
+{
+   OSMesaContext ctx;
+   void *buffer;
+
+   /* Create an RGBA-mode context */
+   ctx = OSMesaCreateContext( GL_RGBA, NULL );
+
+   /* Allocate the image buffer */
+   buffer = malloc( WIDTH * HEIGHT * 4 );
+
+   /* Bind the buffer to the context and make it current */
+   OSMesaMakeCurrent( ctx, buffer, GL_UNSIGNED_BYTE, WIDTH, HEIGHT );
+
+   render_image();
+
+   if (argc>1) {
+      /* write PPM file */
+      FILE *f = fopen( argv[1], "w" );
+      if (f) {
+         int i, x, y;
+         GLubyte *ptr = (GLubyte *) buffer;
+#define BINARY 0
+#if BINARY
+         fprintf(f,"P6\n");
+         fprintf(f,"# ppm-file created by %s\n",  argv[0]);
+         fprintf(f,"%i %i\n", WIDTH,HEIGHT);
+         fprintf(f,"255\n");
+         fclose(f);
+         f = fopen( argv[1], "ab" );  /* reopen in binary append mode */
+         for (y=HEIGHT-1; y>=0; y--) {
+            for (x=0; x<WIDTH; x++) {
+               i = (y*WIDTH + x) * 4;
+               fputc(ptr[i], f);   /* write red */
+               fputc(ptr[i+1], f); /* write green */
+               fputc(ptr[i+2], f); /* write blue */
+            }
+         }
+#else /*ASCII*/
+         int counter = 0;
+         fprintf(f,"P3\n");
+         fprintf(f,"# ascii ppm file created by %s\n", argv[0]);
+         fprintf(f,"%i %i\n", WIDTH, HEIGHT);
+         fprintf(f,"255\n");
+         for (y=HEIGHT-1; y>=0; y--) {
+            for (x=0; x<WIDTH; x++) {
+               i = (y*WIDTH + x) * 4;
+               fprintf(f, " %3d %3d %3d", ptr[i], ptr[i+1], ptr[i+2]);
+               counter++;
+               if (counter % 5 == 0)
+                  fprintf(f, "\n");
+            }
+         }
+#endif
+         fclose(f);
+      }
+   }
+   else {
+      printf("Specify a filename if you want to make a ppm file\n");
+   }
+
+   printf("all done\n");
+
+   /* free the image buffer */
+   free( buffer );
+
+   /* destroy the context */
+   OSMesaDestroyContext( ctx );
+
+   return 0;
+}