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    fflush(stderr);
  44
  45    glClearColor(0.0, 0.0, 1.0, 0.0);
  46
  47 #define SIZE 16
  48    {
  49       GLubyte tex3d[SIZE][SIZE][SIZE][3];
  50       GLint r, s, t;
  51
  52       for (s = 0; s < SIZE; s++) {
  53          for (t = 0; t < SIZE; t++) {
  54             for (r = 0; r < SIZE; r++) {
  55 #if 0
  56                tex3d[r][t][s][0] = (s < SIZE/2) ? 0 : 255;
  57                tex3d[r][t][s][1] = (t < SIZE/2) ? 0 : 255;
  58                tex3d[r][t][s][2] = (r < SIZE/2) ? 0 : 255;
  59 #else
  60                tex3d[r][t][s][0] = s*255/(SIZE-1);
  61                tex3d[r][t][s][1] = t*255/(SIZE-1);
  62                tex3d[r][t][s][2] = r*255/(SIZE-1);
  63 #endif
  64             }
  65          }
  66       }
  67
  68       glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
  69       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_WRAP_R, GL_REPEAT);
  70       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
  71       glTexParameterf(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  72
  73       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  74       glTexImage3D(GL_TEXTURE_3D, 0, 3, SIZE, SIZE, SIZE, 0,
  75                    GL_RGB, GL_UNSIGNED_BYTE, tex3d);
  76       glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
  77       glEnable(GL_TEXTURE_3D);
  78    }
  79
  80 }
  81
  82 static void Reshape(int width, int height)
  83 {
  84
  85     glViewport(0, 0, (GLint)width, (GLint)height);
  86
  87     glMatrixMode(GL_PROJECTION);
  88     glLoadIdentity();
  89     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  90     glMatrixMode(GL_MODELVIEW);
  91 }
  92
  93 static void Key(unsigned char key, int x, int y)
  94 {
  95
  96     switch (key) {
  97     case ' ':
  98        z += 1.0/SIZE;
  99        break;
 100       case 27:
 101         exit(1);
 102       default:
 103         return;
 104     }
 105
 106     glutPostRedisplay();
 107 }
 108
 109 static void Draw(void)
 110 {
 111    glClear(GL_COLOR_BUFFER_BIT);
 112
 113    fprintf(stderr, "z: %f\n", z);
 114
 115    glBegin(GL_QUADS);
 116    glTexCoord3f(1,0,z);
 117    glVertex3f( 0.9, -0.9, -30.0);
 118    glTexCoord3f(1,1,z);
 119    glVertex3f( 0.9,  0.9, -30.0);
 120    glTexCoord3f(0,1,z);
 121    glVertex3f(-0.9,  0.9, -30.0);
 122    glTexCoord3f(0,0,z);
 123    glVertex3f(-0.9,  -0.9, -30.0);
 124    glEnd();
 125
 126    glFlush();
 127
 128    if (doubleBuffer) {
 129       glutSwapBuffers();
 130    }
 131 }
 132
 133 static GLenum Args(int argc, char **argv)
 134 {
 135     GLint i;
 136
 137     doubleBuffer = GL_FALSE;
 138
 139     for (i = 1; i < argc; i++) {
 140         if (strcmp(argv[i], "-sb") == 0) {
 141             doubleBuffer = GL_FALSE;
 142         } else if (strcmp(argv[i], "-db") == 0) {
 143             doubleBuffer = GL_TRUE;
 144         } else {
 145             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 146             return GL_FALSE;
 147         }
 148     }
 149     return GL_TRUE;
 150 }
 151
 152 int main(int argc, char **argv)
 153 {
 154     GLenum type;
 155
 156     glutInit(&argc, argv);
 157
 158     if (Args(argc, argv) == GL_FALSE) {
 159         exit(1);
 160     }
 161
 162     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 163
 164     type = GLUT_RGB | GLUT_ALPHA;
 165     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 166     glutInitDisplayMode(type);
 167
 168     if (glutCreateWindow(*argv) == GL_FALSE) {
 169         exit(1);
 170     }
 171
 172     glewInit();
 173
 174     Init();
 175
 176     glutReshapeFunc(Reshape);
 177     glutKeyboardFunc(Key);
 178     glutDisplayFunc(Draw);
 179     glutMainLoop();
 180         return 0;
 181 }