progs/trivial/quad-tex-2d.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 static GLenum Target = GL_TEXTURE_2D;
  31 static GLenum Filter = GL_NEAREST;
  32 GLenum doubleBuffer;
  33 static float Rot = 0;
  34 static int win = 0;
  35
  36 static void Init(void)
  37 {
  38    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  39    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  40    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  41    fflush(stderr);
  42
  43    glClearColor(0.0, 0.0, 1.0, 0.0);
  44
  45 #define SIZE 32
  46    {
  47       GLubyte tex2d[SIZE][SIZE][3];
  48       GLint s, t;
  49
  50       for (s = 0; s < SIZE; s++) {
  51          for (t = 0; t < SIZE; t++) {
  52 #if 0
  53             tex2d[t][s][0] = (s < SIZE/2) ? 0 : 255;
  54             tex2d[t][s][1] = (t < SIZE/2) ? 0 : 255;
  55             tex2d[t][s][2] = 0;
  56 #else
  57             tex2d[t][s][0] = s*255/(SIZE-1);
  58             tex2d[t][s][1] = t*255/(SIZE-1);
  59             tex2d[t][s][2] = 0;
  60 #endif
  61          }
  62       }
  63
  64       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  65
  66       if (Target == GL_TEXTURE_1D)
  67          glTexImage1D(Target, 0, 3, SIZE, 0, GL_RGB, GL_UNSIGNED_BYTE, tex2d);
  68       else
  69          glTexImage2D(Target, 0, 3, SIZE, SIZE, 0,
  70                       GL_RGB, GL_UNSIGNED_BYTE, tex2d);
  71
  72       glEnable(Target);
  73       glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
  74       glTexParameterf(Target, GL_TEXTURE_WRAP_R, GL_REPEAT);
  75       glTexParameterf(Target, GL_TEXTURE_MIN_FILTER, Filter);
  76       glTexParameterf(Target, GL_TEXTURE_MAG_FILTER, Filter);
  77
  78       glPixelStorei(GL_UNPACK_ALIGNMENT, 4);
  79    }
  80 }
  81
  82 static void Reshape(int width, int height)
  83 {
  84    glViewport(0, 0, (GLint)width, (GLint)height);
  85    glMatrixMode(GL_PROJECTION);
  86    glLoadIdentity();
  87 #if 0
  88    glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  89 #else
  90    glFrustum(-1, 1, -1, 1, 10, 20);
  91 #endif
  92    glMatrixMode(GL_MODELVIEW);
  93    glLoadIdentity();
  94    glTranslatef(0, 0, -15);
  95 }
  96
  97 static void Key(unsigned char key, int x, int y)
  98 {
  99    switch (key) {
 100    case 'r':
 101       Rot += 10.0;
 102       break;
 103    case 'R':
 104       Rot -= 10.0;
 105       break;
 106    case 27:
 107       glutDestroyWindow(win);
 108       exit(0);
 109    default:
 110       return;
 111    }
 112    glutPostRedisplay();
 113 }
 114
 115 static void Draw(void)
 116 {
 117    glClear(GL_COLOR_BUFFER_BIT);
 118
 119    glPushMatrix();
 120    glRotatef(Rot, 0, 1, 0);
 121
 122    glBegin(GL_QUADS);
 123    glTexCoord2f(1,0);
 124    glVertex3f( 0.9, -0.9, 0.0);
 125    glTexCoord2f(1,1);
 126    glVertex3f( 0.9,  0.9, 0.0);
 127    glTexCoord2f(0,1);
 128    glVertex3f(-0.9,  0.9, 0.0);
 129    glTexCoord2f(0,0);
 130    glVertex3f(-0.9,  -0.9, 0.0);
 131    glEnd();
 132
 133    glPopMatrix();
 134
 135    glFlush();
 136
 137    if (doubleBuffer) {
 138       glutSwapBuffers();
 139    }
 140 }
 141
 142 static GLenum Args(int argc, char **argv)
 143 {
 144     GLint i;
 145
 146     doubleBuffer = GL_FALSE;
 147
 148     for (i = 1; i < argc; i++) {
 149         if (strcmp(argv[i], "-sb") == 0) {
 150             doubleBuffer = GL_FALSE;
 151         } else if (strcmp(argv[i], "-db") == 0) {
 152             doubleBuffer = GL_TRUE;
 153         } else {
 154             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 155             return GL_FALSE;
 156         }
 157     }
 158     return GL_TRUE;
 159 }
 160
 161 int main(int argc, char **argv)
 162 {
 163     GLenum type;
 164
 165     glutInit(&argc, argv);
 166
 167     if (Args(argc, argv) == GL_FALSE) {
 168         exit(1);
 169     }
 170
 171     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 172
 173     type = GLUT_RGB;
 174     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 175     glutInitDisplayMode(type);
 176
 177     win = glutCreateWindow(*argv);
 178     if (!win) {
 179         exit(1);
 180     }
 181
 182     Init();
 183
 184     glutReshapeFunc(Reshape);
 185     glutKeyboardFunc(Key);
 186     glutDisplayFunc(Draw);
 187     glutMainLoop();
 188     return 0;
 189 }