2 * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
4 * Permission to use, copy, modify, distribute, and sell this software and
5 * its documentation for any purpose is hereby granted without fee, provided
6 * that (i) the above copyright notices and this permission notice appear in
7 * all copies of the software and related documentation, and (ii) the name of
8 * Silicon Graphics may not be used in any advertising or
9 * publicity relating to the software without the specific, prior written
10 * permission of Silicon Graphics.
12 * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
14 * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
15 * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
17 * IN NO EVENT SHALL SILICON GRAPHICS BE LIABLE FOR
18 * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
19 * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
20 * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
21 * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
31 #define CI_OFFSET_1 16
32 #define CI_OFFSET_2 32
37 static void Init(void)
39 fprintf(stderr, "GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
40 fprintf(stderr, "GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
41 fprintf(stderr, "GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
46 static void Reshape(int width, int height)
49 glViewport(0, 0, (GLint)width, (GLint)height);
51 glMatrixMode(GL_PROJECTION);
53 glOrtho(-1.0, 1.0, -1.0, 1.0, 1, -1);
54 glMatrixMode(GL_MODELVIEW);
57 static void Key(unsigned char key, int x, int y)
70 static void Draw(void)
74 glClearColor(0.0, 0.0, 1.0, 0.0);
76 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
77 glDepthFunc(GL_EQUAL);
78 glEnable(GL_DEPTH_TEST);
80 glBegin(GL_TRIANGLES);
82 glVertex3f( 0.9, -0.9, z);
84 glVertex3f( 0.9, 0.9, z);
86 glVertex3f(-0.9, 0.0, z);
93 glReadPixels(125, 125, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &z);
94 printf("Z at (125, 125) = %f\n", z);
102 static GLenum Args(int argc, char **argv)
106 doubleBuffer = GL_FALSE;
108 for (i = 1; i < argc; i++) {
109 if (strcmp(argv[i], "-sb") == 0) {
110 doubleBuffer = GL_FALSE;
111 } else if (strcmp(argv[i], "-db") == 0) {
112 doubleBuffer = GL_TRUE;
114 fprintf(stderr, "%s (Bad option).\n", argv[i]);
121 int main(int argc, char **argv)
125 glutInit(&argc, argv);
127 if (Args(argc, argv) == GL_FALSE) {
131 glutInitWindowPosition(100, 0); glutInitWindowSize( 250, 250);
133 type = GLUT_RGB | GLUT_DEPTH;
134 type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
135 glutInitDisplayMode(type);
137 if (glutCreateWindow(*argv) == GL_FALSE) {
143 glutReshapeFunc(Reshape);
144 glutKeyboardFunc(Key);
145 glutDisplayFunc(Draw);