progs/trivial/quadstrip.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 GLenum doubleBuffer;
  31
  32 static void Init(void)
  33 {
  34    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  35    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  36    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  37
  38     glClearColor(0.0, 0.0, 1.0, 0.0);
  39 }
  40
  41 static void Reshape(int width, int height)
  42 {
  43
  44     glViewport(0, 0, (GLint)width, (GLint)height);
  45
  46     glMatrixMode(GL_PROJECTION);
  47     glLoadIdentity();
  48     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  49     glMatrixMode(GL_MODELVIEW);
  50 }
  51
  52 static void Key(unsigned char key, int x, int y)
  53 {
  54
  55     switch (key) {
  56       case 27:
  57         exit(1);
  58       default:
  59         return;
  60     }
  61
  62     glutPostRedisplay();
  63 }
  64
  65 static void Draw(void)
  66 {
  67    glClear(GL_COLOR_BUFFER_BIT);
  68
  69    glBegin(GL_QUAD_STRIP);
  70    glColor3f(1,0,0);
  71    glVertex3f( 0.9, -0.9, -30.0);
  72    glColor3f(1,1,0);
  73    glVertex3f( 0.9,  0.9, -30.0);
  74
  75    glColor3f(1,0,0);
  76    glVertex3f( 0.1, -0.8, -30.0);
  77    glColor3f(1,1,0);
  78    glVertex3f( 0.1,  0.8, -30.0);
  79
  80    glColor3f(0,1,1);
  81    glVertex3f(-0.1,  -0.9, -30.0);
  82    glColor3f(1,0,1);
  83    glVertex3f(-0.1,  0.9, -30.0);
  84
  85    glColor3f(0,1,1);
  86    glVertex3f(-0.9,  -0.8, -30.0);
  87    glColor3f(1,0,1);
  88    glVertex3f(-0.9,  0.8, -30.0);
  89    glEnd();
  90
  91    glFlush();
  92
  93    if (doubleBuffer) {
  94       glutSwapBuffers();
  95    }
  96 }
  97
  98 static GLenum Args(int argc, char **argv)
  99 {
 100     GLint i;
 101
 102     doubleBuffer = GL_FALSE;
 103
 104     for (i = 1; i < argc; i++) {
 105         if (strcmp(argv[i], "-sb") == 0) {
 106             doubleBuffer = GL_FALSE;
 107         } else if (strcmp(argv[i], "-db") == 0) {
 108             doubleBuffer = GL_TRUE;
 109         } else {
 110             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 111             return GL_FALSE;
 112         }
 113     }
 114     return GL_TRUE;
 115 }
 116
 117 int main(int argc, char **argv)
 118 {
 119     GLenum type;
 120
 121     glutInit(&argc, argv);
 122
 123     if (Args(argc, argv) == GL_FALSE) {
 124         exit(1);
 125     }
 126
 127     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 128
 129     type = GLUT_RGB | GLUT_ALPHA;
 130     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 131     glutInitDisplayMode(type);
 132
 133     if (glutCreateWindow(*argv) == GL_FALSE) {
 134         exit(1);
 135     }
 136
 137     Init();
 138
 139     glutReshapeFunc(Reshape);
 140     glutKeyboardFunc(Key);
 141     glutDisplayFunc(Draw);
 142     glutMainLoop();
 143         return 0;
 144 }