src/redbook/hello.c

   1 /*
   2  * Copyright (c) 1993-1997, Silicon Graphics, Inc.
   3  * ALL RIGHTS RESERVED
   4  * Permission to use, copy, modify, and distribute this software for
   5  * any purpose and without fee is hereby granted, provided that the above
   6  * copyright notice appear in all copies and that both the copyright notice
   7  * and this permission notice appear in supporting documentation, and that
   8  * the name of Silicon Graphics, Inc. not be used in advertising
   9  * or publicity pertaining to distribution of the software without specific,
  10  * written prior permission.
  11  *
  12  * THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
  13  * AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
  14  * INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
  15  * FITNESS FOR A PARTICULAR PURPOSE.  IN NO EVENT SHALL SILICON
  16  * GRAPHICS, INC.  BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
  17  * SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
  18  * KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
  19  * LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
  20  * THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC.  HAS BEEN
  21  * ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
  22  * ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
  23  * POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
  24  *
  25  * US Government Users Restricted Rights
  26  * Use, duplication, or disclosure by the Government is subject to
  27  * restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
  28  * (c)(1)(ii) of the Rights in Technical Data and Computer Software
  29  * clause at DFARS 252.227-7013 and/or in similar or successor
  30  * clauses in the FAR or the DOD or NASA FAR Supplement.
  31  * Unpublished-- rights reserved under the copyright laws of the
  32  * United States.  Contractor/manufacturer is Silicon Graphics,
  33  * Inc., 2011 N.  Shoreline Blvd., Mountain View, CA 94039-7311.
  34  *
  35  * OpenGL(R) is a registered trademark of Silicon Graphics, Inc.
  36  */
  37
  38 /*
  39  * hello.c
  40  * This is a simple, introductory OpenGL program.
  41  */
  42 #include <stdlib.h>
  43 #include <GL/glut.h>
  44
  45 void display(void)
  46 {
  47 /* clear all pixels  */
  48    glClear (GL_COLOR_BUFFER_BIT);
  49
  50 /* draw white polygon (rectangle) with corners at
  51  * (0.25, 0.25, 0.0) and (0.75, 0.75, 0.0)
  52  */
  53    glColor3f (1.0, 1.0, 1.0);
  54    glBegin(GL_POLYGON);
  55       glVertex3f (0.25, 0.25, 0.0);
  56       glVertex3f (0.75, 0.25, 0.0);
  57       glVertex3f (0.75, 0.75, 0.0);
  58       glVertex3f (0.25, 0.75, 0.0);
  59    glEnd();
  60
  61 /* don't wait!
  62  * start processing buffered OpenGL routines
  63  */
  64    glFlush ();
  65 }
  66
  67 void init (void)
  68 {
  69 /* select clearing color        */
  70    glClearColor (0.0, 0.0, 0.0, 0.0);
  71
  72 /* initialize viewing values  */
  73    glMatrixMode(GL_PROJECTION);
  74    glLoadIdentity();
  75    glOrtho(0.0, 1.0, 0.0, 1.0, -1.0, 1.0);
  76 }
  77
  78 static void
  79 key(unsigned char k, int x, int y)
  80 {
  81   switch (k) {
  82   case 27:  /* Escape */
  83     exit(0);
  84     break;
  85   default:
  86     return;
  87   }
  88   glutPostRedisplay();
  89 }
  90
  91 /*
  92  * Declare initial window size, position, and display mode
  93  * (single buffer and RGBA).  Open window with "hello"
  94  * in its title bar.  Call initialization routines.
  95  * Register callback function to display graphics.
  96  * Enter main loop and process events.
  97  */
  98 int main(int argc, char** argv)
  99 {
 100    glutInit(&argc, argv);
 101    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB);
 102    glutInitWindowSize (250, 250);
 103    glutInitWindowPosition (100, 100);
 104    glutCreateWindow ("hello");
 105    init ();
 106    glutDisplayFunc(display);
 107    glutKeyboardFunc(key);
 108    glutMainLoop();
 109    return 0;   /* ANSI C requires main to return int. */
 110 }