progs/trivial/tri.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 doubleBuffer = 1;
  36 int win;
  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(0.3, 0.1, 0.3, 0.0);
  46 }
  47
  48 static void Reshape(int width, int height)
  49 {
  50
  51    glViewport(0, 0, (GLint)width, (GLint)height);
  52
  53    glMatrixMode(GL_PROJECTION);
  54    glLoadIdentity();
  55    glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  56    glMatrixMode(GL_MODELVIEW);
  57 }
  58
  59 static void Key(unsigned char key, int x, int y)
  60 {
  61    switch (key) {
  62       case 27:
  63          glutDestroyWindow(win);
  64          exit(0);
  65       default:
  66          glutPostRedisplay();
  67          return;
  68    }
  69 }
  70
  71 static void Draw(void)
  72 {
  73    glClear(GL_COLOR_BUFFER_BIT);
  74
  75    glBegin(GL_TRIANGLES);
  76    glColor3f(.8,0,0);
  77    glVertex3f(-0.9, -0.9, -30.0);
  78    glColor3f(0,.9,0);
  79    glVertex3f( 0.9, -0.9, -30.0);
  80    glColor3f(0,0,.7);
  81    glVertex3f( 0.0,  0.9, -30.0);
  82    glEnd();
  83
  84    glFlush();
  85
  86    if (doubleBuffer) {
  87       glutSwapBuffers();
  88    }
  89 }
  90
  91 static GLenum Args(int argc, char **argv)
  92 {
  93    GLint i;
  94
  95    for (i = 1; i < argc; i++) {
  96       if (strcmp(argv[i], "-sb") == 0) {
  97          doubleBuffer = GL_FALSE;
  98       } else if (strcmp(argv[i], "-db") == 0) {
  99          doubleBuffer = GL_TRUE;
 100       } else {
 101          fprintf(stderr, "%s (Bad option).\n", argv[i]);
 102          return GL_FALSE;
 103       }
 104    }
 105    return GL_TRUE;
 106 }
 107
 108 int main(int argc, char **argv)
 109 {
 110    GLenum type;
 111
 112    glutInit(&argc, argv);
 113
 114    if (Args(argc, argv) == GL_FALSE) {
 115       exit(1);
 116    }
 117
 118    glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 119
 120    type = GLUT_RGB | GLUT_ALPHA;
 121    type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 122    glutInitDisplayMode(type);
 123
 124    win = glutCreateWindow(*argv);
 125    if (!win) {
 126       exit(1);
 127    }
 128
 129    Init();
 130
 131    glutReshapeFunc(Reshape);
 132    glutKeyboardFunc(Key);
 133    glutDisplayFunc(Draw);
 134    glutMainLoop();
 135    return 0;
 136 }