progs/trivial/quad-tex-3d.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/glew.h>
  29 #include <GL/glut.h>
  30
  31
  32 #define CI_OFFSET_1 16
  33 #define CI_OFFSET_2 32
  34
  35 GLfloat z= 0;
  36 GLenum doubleBuffer;
  37
  38 static void Init(void)
  39 {
  40    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  41    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  42    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  43
  44    glClearColor(0.0, 0.0, 1.0, 0.0);
  45
  46 #define SIZE 16
  47    {
  48       GLubyte tex3d[SIZE][SIZE][SIZE][3];
  49       GLint r, s, t;
  50
  51       for (s = 0; s < SIZE; s++) {
  52          for (t = 0; t < SIZE; t++) {
  53             for (r = 0; r < SIZE; r++) {
  54 #if 0
  55                tex3d[r][t][s][0] = (s < SIZE/2) ? 0 : 255;
  56                tex3d[r][t][s][1] = (t < SIZE/2) ? 0 : 255;
  57                tex3d[r][t][s][2] = (r < SIZE/2) ? 0 : 255;
  58 #else
  59                tex3d[r][t][s][0] = s*255/(SIZE-1);
  60                tex3d[r][t][s][1] = t*255/(SIZE-1);
  61                tex3d[r][t][s][2] = r*255/(SIZE-1);
  62 #endif
  63             }
  64          }
  65       }
  66
  67       glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
  68       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_REPEAT);
  69       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  70       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  71
  72       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  73       glTexImage3D(GL_TEXTURE_3D, 0, 3, SIZE, SIZE, SIZE, 0,
  74                    GL_RGB, GL_UNSIGNED_BYTE, tex3d);
  75       glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
  76       glEnable(GL_TEXTURE_3D);
  77    }
  78
  79 }
  80
  81 static void Reshape(int width, int height)
  82 {
  83
  84     glViewport(0, 0, (GLint)width, (GLint)height);
  85
  86     glMatrixMode(GL_PROJECTION);
  87     glLoadIdentity();
  88     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  89     glMatrixMode(GL_MODELVIEW);
  90 }
  91
  92 static void Key(unsigned char key, int x, int y)
  93 {
  94
  95     switch (key) {
  96     case ' ':
  97        z += 1.0/SIZE;
  98        break;
  99       case 27:
 100         exit(1);
 101       default:
 102         return;
 103     }
 104
 105     glutPostRedisplay();
 106 }
 107
 108 static void Draw(void)
 109 {
 110    glClear(GL_COLOR_BUFFER_BIT);
 111
 112    fprintf(stderr, "z: %f\n", z);
 113
 114    glBegin(GL_QUADS);
 115    glTexCoord3f(1,0,z);
 116    glVertex3f( 0.9, -0.9, -30.0);
 117    glTexCoord3f(1,1,z);
 118    glVertex3f( 0.9,  0.9, -30.0);
 119    glTexCoord3f(0,1,z);
 120    glVertex3f(-0.9,  0.9, -30.0);
 121    glTexCoord3f(0,0,z);
 122    glVertex3f(-0.9,  -0.9, -30.0);
 123    glEnd();
 124
 125    glFlush();
 126
 127    if (doubleBuffer) {
 128       glutSwapBuffers();
 129    }
 130 }
 131
 132 static GLenum Args(int argc, char **argv)
 133 {
 134     GLint i;
 135
 136     doubleBuffer = GL_FALSE;
 137
 138     for (i = 1; i < argc; i++) {
 139         if (strcmp(argv[i], "-sb") == 0) {
 140             doubleBuffer = GL_FALSE;
 141         } else if (strcmp(argv[i], "-db") == 0) {
 142             doubleBuffer = GL_TRUE;
 143         } else {
 144             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 145             return GL_FALSE;
 146         }
 147     }
 148     return GL_TRUE;
 149 }
 150
 151 int main(int argc, char **argv)
 152 {
 153     GLenum type;
 154
 155     glutInit(&argc, argv);
 156
 157     if (Args(argc, argv) == GL_FALSE) {
 158         exit(1);
 159     }
 160
 161     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 162
 163     type = GLUT_RGB | GLUT_ALPHA;
 164     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 165     glutInitDisplayMode(type);
 166
 167     if (glutCreateWindow("First Tri") == GL_FALSE) {
 168         exit(1);
 169     }
 170
 171     glewInit();
 172
 173     Init();
 174
 175     glutReshapeFunc(Reshape);
 176     glutKeyboardFunc(Key);
 177     glutDisplayFunc(Draw);
 178     glutMainLoop();
 179         return 0;
 180 }