void draw_shadow(int shad)
{
int x = 0;
#ifdef GL_VERSION_1_1
if (supportsOneDotOne() && !forceExtension) {
polygonOffsetVersion = ONE_DOT_ONE;
glPolygonOffset(-2.0, -1.0);
} else
#endif
{
#ifdef GL_EXT_polygon_offset
/* check for the polygon offset extension */
if (glutExtensionSupported("GL_EXT_polygon_offset")) {
polygonOffsetVersion = EXTENSION;
glPolygonOffsetEXT(-0.1, -0.002);
} else
#endif
{
polygonOffsetVersion = MISSING;
//printf("\nMissing polygon offset.\n");
//printf("Expect shadow depth aliasing artifacts.\n\n");
}
}
findPlane(floorPlane, floorVertices[1], floorVertices[2], floorVertices[3]);
redraw(shad);
}
int
main(int argc, char **argv)
{
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
glutCreateWindow("offset");
glutDisplayFunc(draw_scene);
#ifdef GL_VERSION_1_1
if (supportsOneDotOne()) {
glPolygonOffset(2.0, 1);
version = MODE_11;
} else
#endif
{
#ifdef GL_EXT_polygon_offset
/* check for the polygon offset extension */
if (glutExtensionSupported("GL_EXT_polygon_offset")) {
glPolygonOffsetEXT(0.75, 0.00);
version = MODE_EXT;
} else
#endif
{
error(argv[0], "Warning: running with out the polygon offset extension.\n");
version = MODE_NONE;
}
}
/* set up viewing parameters */
glMatrixMode(GL_PROJECTION);
gluPerspective(20, 1, 0.1, 20);
glMatrixMode(GL_MODELVIEW);
glTranslatef(0, 0, -15);
/* set other relevant state information */
glEnable(GL_DEPTH_TEST);
glShadeModel(GL_FLAT);
glDisable(GL_DITHER);
glutMainLoop();
return 0; /* ANSI C requires main to return int. */
}
int
main(int argc, char **argv)
{
int i;
glutInit(&argc, argv);
for (i=1; i<argc; i++) {
if (!strcmp("-linear", argv[i])) {
linearFiltering = 1;
} else if (!strcmp("-mipmap", argv[i])) {
useMipmaps = 1;
} else if (!strcmp("-ext", argv[i])) {
forceExtension = 1;
}
}
glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_STENCIL | GLUT_MULTISAMPLE);
#if 1
/* In GLUT 4.0, you'll be able to do this an be sure to
get 2 bits of stencil if the machine has it for you. */
glutInitDisplayString("samples stencil~3 rgb double depth");
#endif
glutCreateWindow("OpenGL Halo Magic (hit Space)");
if (glutGet(GLUT_WINDOW_STENCIL_SIZE) < 3) {
printf("halomagic: Sorry, I need at least 3 bits of stencil.\n");
exit(1);
}
/* Register GLUT callbacks. */
glutDisplayFunc(redraw);
glutMouseFunc(mouse);
glutMotionFunc(motion);
glutVisibilityFunc(visible);
glutKeyboardFunc(key);
glutSpecialFunc(special);
glutCreateMenu(controlLights);
glutAddMenuEntry("Toggle halo blending", M_BLENDED_HALO);
glutAddMenuEntry("Show halo", M_SHOW_HALO);
glutAddMenuEntry("Switch model", M_SWITCH_MODEL);
glutAddMenuEntry("Toggle motion", M_MOTION);
glutAddMenuEntry("-----------------------", M_NONE);
glutAddMenuEntry("Toggle light", M_LIGHT);
glutAddMenuEntry("Toggle texture", M_TEXTURE);
glutAddMenuEntry("Toggle shadows", M_SHADOWS);
glutAddMenuEntry("Toggle reflection", M_REFLECTION);
glutAddMenuEntry("Toggle object", M_DINOSAUR);
glutAddMenuEntry("-----------------------", M_NONE);
glutAddMenuEntry("Toggle reflection stenciling", M_STENCIL_REFLECTION);
glutAddMenuEntry("Toggle shadow stenciling", M_STENCIL_SHADOW);
glutAddMenuEntry("Toggle shadow offset", M_OFFSET_SHADOW);
glutAddMenuEntry("----------------------", M_NONE);
glutAddMenuEntry("Positional light", M_POSITIONAL);
glutAddMenuEntry("Directional light", M_DIRECTIONAL);
glutAddMenuEntry("-----------------------", M_NONE);
glutAddMenuEntry("Toggle performance", M_PERFORMANCE);
glutAttachMenu(GLUT_RIGHT_BUTTON);
makeDinosaur();
#ifdef GL_VERSION_1_1
if (supportsOneDotOne() && !forceExtension) {
polygonOffsetVersion = ONE_DOT_ONE;
glPolygonOffset(-2.0, -1.0);
} else
#endif
{
#if defined(GL_EXT_polygon_offset) && !defined(GL_VERSION_1_1)
/* check for the polygon offset extension */
if (glutExtensionSupported("GL_EXT_polygon_offset")) {
polygonOffsetVersion = EXTENSION;
glPolygonOffsetEXT(-0.1, -0.002);
} else
#endif
{
polygonOffsetVersion = MISSING;
printf("\ndinoshine: Missing polygon offset.\n");
printf(" Expect shadow depth aliasing artifacts.\n\n");
}
}
glEnable(GL_CULL_FACE);
glEnable(GL_DEPTH_TEST);
glLineWidth(3.0);
glMatrixMode(GL_PROJECTION);
gluPerspective( /* field of view in degree */ 40.0,
/* aspect ratio */ 1.0,
/* Z near */ 20.0, /* Z far */ 100.0);
glMatrixMode(GL_MODELVIEW);
gluLookAt(0.0, 8.0, 60.0, /* eye is at (0,0,30) */
0.0, 8.0, 0.0, /* center is at (0,0,0) */
0.0, 1.0, 0.); /* up is in postivie Y direction */
glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, 1);
glLightfv(GL_LIGHT0, GL_DIFFUSE, lightColor);
glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 0.1);
glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 0.05);
glEnable(GL_LIGHT0);
glEnable(GL_LIGHTING);
makeFloorTexture();
/* Setup floor plane for projected shadow calculations. */
findPlane(floorPlane, floorVertices[1], floorVertices[2], floorVertices[3]);
glutMainLoop();
return 0; /* ANSI C requires main to return int. */
}
