12
GLint Width = 200, Height = 150;
14
static void Init(void)
16
fprintf(stderr, "GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
17
fprintf(stderr, "GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
18
fprintf(stderr, "GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
22
static void Reshape(int width, int height)
27
glViewport(0, 0, (GLint)width, (GLint)height);
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glMatrixMode(GL_PROJECTION);
31
glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
32
glMatrixMode(GL_MODELVIEW);
35
static void Key(unsigned char key, int x, int y)
46
static void Draw(void)
48
glEnable(GL_SCISSOR_TEST);
50
glClearColor(1, 0, 0, 0);
51
glScissor(0, 0, Width / 2, Height / 2);
52
glClear(GL_COLOR_BUFFER_BIT);
54
glClearColor(0, 1, 0, 0);
55
glScissor(Width / 2, 0, Width - Width / 2, Height / 2);
56
glClear(GL_COLOR_BUFFER_BIT);
58
glClearColor(0, 0, 1, 0);
59
glScissor(0, Height / 2, Width / 2, Height - Height / 2);
60
glClear(GL_COLOR_BUFFER_BIT);
62
glClearColor(1, 1, 1, 0);
63
glScissor(Width / 2, Height / 2, Width - Width / 2, Height - Height / 2);
64
glClear(GL_COLOR_BUFFER_BIT);
73
static GLenum Args(int argc, char **argv)
77
doubleBuffer = GL_FALSE;
79
for (i = 1; i < argc; i++) {
80
if (strcmp(argv[i], "-sb") == 0) {
81
doubleBuffer = GL_FALSE;
82
} else if (strcmp(argv[i], "-db") == 0) {
83
doubleBuffer = GL_TRUE;
85
fprintf(stderr, "%s (Bad option).\n", argv[i]);
92
int main(int argc, char **argv)
96
glutInit(&argc, argv);
98
if (Args(argc, argv) == GL_FALSE) {
102
glutInitWindowPosition(0, 0); glutInitWindowSize( Width, Height );
104
type = GLUT_RGB | GLUT_ALPHA;
105
type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
106
glutInitDisplayMode(type);
108
if (glutCreateWindow(argv[0]) == GL_FALSE) {
114
glutReshapeFunc(Reshape);
115
glutKeyboardFunc(Key);
116
glutDisplayFunc(Draw);