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