progs/samples/depth.c

   1 /*
   2  * Copyright (c) 1991, 1992, 1993 Silicon Graphics, Inc.
   3  *
   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.
  11  *
  12  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF
  13  * ANY KIND,
  14  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
  15  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
  16  *
  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
  22  * OF THIS SOFTWARE.
  23  */
  24
  25 #include <stdio.h>
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <GL/glut.h>
  29
  30
  31 #define CI_OFFSET_1 16
  32 #define CI_OFFSET_2 32
  33
  34
  35 GLenum rgb, doubleBuffer;
  36
  37 GLenum antiAlias, stipple;
  38 GLubyte stippleBits[32*4] = {
  39     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  40     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  41     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  42     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  43     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  44     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  45     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  46     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  47     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  48     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  49     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  50     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  51     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  52     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  53     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  54     0xAA, 0xAA, 0xAA, 0xAA, 0x55, 0x55, 0x55, 0x55,
  55 };
  56
  57
  58 #include "tkmap.c"
  59
  60 static void Init(void)
  61 {
  62     GLint i;
  63
  64     glClearColor(0.0, 0.0, 0.0, 0.0);
  65     glClearIndex(0.0);
  66
  67     if (!rgb) {
  68         for (i = 0; i < 16; i++) {
  69             glutSetColor(i+CI_OFFSET_1, 0.0, 0.0, i/15.0);
  70             glutSetColor(i+CI_OFFSET_2, 0.0, i/15.0, 0.0);
  71         }
  72     }
  73
  74     glPolygonStipple(stippleBits);
  75
  76     antiAlias = GL_FALSE;
  77     stipple = GL_FALSE;
  78 }
  79
  80 static void Reshape(int width, int height)
  81 {
  82
  83     glViewport(0, 0, (GLint)width, (GLint)height);
  84
  85     glMatrixMode(GL_PROJECTION);
  86     glLoadIdentity();
  87     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  88     glMatrixMode(GL_MODELVIEW);
  89 }
  90
  91 static void Key(unsigned char key, int x, int y)
  92 {
  93
  94     switch (key) {
  95       case 27:
  96         exit(1);
  97       case '1':
  98         antiAlias = !antiAlias;
  99         break;
 100       case '2':
 101         stipple = !stipple;
 102         break;
 103       default:
 104         return;
 105     }
 106
 107     glutPostRedisplay();
 108 }
 109
 110 static void Draw(void)
 111 {
 112     GLint ci1, ci2;
 113
 114     glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
 115
 116     if (antiAlias) {
 117         ci1 = CI_OFFSET_1;
 118         ci2 = CI_OFFSET_2;
 119         glBlendFunc(GL_SRC_ALPHA, GL_ONE);
 120         glEnable(GL_BLEND);
 121         glEnable(GL_POLYGON_SMOOTH);
 122         glDisable(GL_DEPTH_TEST);
 123     } else {
 124         ci1 = COLOR_BLUE;
 125         ci2 = COLOR_GREEN;
 126         glDisable(GL_BLEND);
 127         glDisable(GL_POLYGON_SMOOTH);
 128         glEnable(GL_DEPTH_TEST);
 129     }
 130
 131     if (stipple) {
 132         glEnable(GL_POLYGON_STIPPLE);
 133     } else {
 134         glDisable(GL_POLYGON_STIPPLE);
 135     }
 136
 137     glBegin(GL_TRIANGLES);
 138         (rgb) ? glColor3fv(RGBMap[COLOR_BLUE]) : glIndexi(ci1);
 139         glVertex3f( 0.9, -0.9, -30.0);
 140         glVertex3f( 0.9,  0.9, -30.0);
 141         glVertex3f(-0.9,  0.0, -30.0);
 142         (rgb) ? glColor3fv(RGBMap[COLOR_GREEN]) : glIndexi(ci2);
 143         glVertex3f(-0.9, -0.9, -40.0);
 144         glVertex3f(-0.9,  0.9, -40.0);
 145         glVertex3f( 0.9,  0.0, -25.0);
 146     glEnd();
 147
 148     glFlush();
 149
 150     if (doubleBuffer) {
 151         glutSwapBuffers();
 152     }
 153 }
 154
 155 static GLenum Args(int argc, char **argv)
 156 {
 157     GLint i;
 158
 159     rgb = GL_TRUE;
 160     doubleBuffer = GL_FALSE;
 161
 162     for (i = 1; i < argc; i++) {
 163         if (strcmp(argv[i], "-ci") == 0) {
 164             rgb = GL_FALSE;
 165         } else if (strcmp(argv[i], "-rgb") == 0) {
 166             rgb = GL_TRUE;
 167         } else if (strcmp(argv[i], "-sb") == 0) {
 168             doubleBuffer = GL_FALSE;
 169         } else if (strcmp(argv[i], "-db") == 0) {
 170             doubleBuffer = GL_TRUE;
 171         } else {
 172             printf("%s (Bad option).\n", argv[i]);
 173             return GL_FALSE;
 174         }
 175     }
 176     return GL_TRUE;
 177 }
 178
 179 int main(int argc, char **argv)
 180 {
 181     GLenum type;
 182
 183     glutInit(&argc, argv);
 184
 185     if (Args(argc, argv) == GL_FALSE) {
 186         exit(1);
 187     }
 188
 189     glutInitWindowPosition(0, 0); glutInitWindowSize( 300, 300);
 190
 191     type = GLUT_DEPTH;
 192     type |= (rgb) ? GLUT_RGB : GLUT_INDEX;
 193     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 194     glutInitDisplayMode(type);
 195
 196     if (glutCreateWindow("Depth Test") == GL_FALSE) {
 197         exit(1);
 198     }
 199
 200     InitMap();
 201
 202     Init();
 203
 204     glutReshapeFunc(Reshape);
 205     glutKeyboardFunc(Key);
 206     glutDisplayFunc(Draw);
 207     glutMainLoop();
 208         return 0;
 209 }