src/trivial/quadstrip-clip.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 "glut_wrap.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    fflush(stderr);
  38
  39    glClearColor(0.0, 0.0, 1.0, 0.0);
  40 }
  41
  42 static void Reshape(int width, int height)
  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    }
  59
  60    glutPostRedisplay();
  61 }
  62
  63 static void Draw(void)
  64 {
  65    glClear(GL_COLOR_BUFFER_BIT);
  66
  67    glBegin(GL_QUAD_STRIP);
  68    glColor3f(1,1,1);
  69    glVertex3f( 1.9, -0.9, -30.0);
  70    glVertex3f( 0.9, 0.9, -30.0);
  71
  72    glColor3f(1,0,0);
  73    glVertex3f( 0.1, -0.8, -30.0);
  74    glVertex3f( 0.1, 0.8, -30.0);
  75
  76    glColor3f(0,1,0);
  77    glVertex3f(-0.1,  -0.9, -30.0);
  78    glVertex3f(-0.1,  0.9, -30.0);
  79
  80    glColor3f(0,0,0);
  81    glVertex3f(-0.9,  -0.8, -30.0);
  82    glVertex3f(-0.9,  0.8, -30.0);
  83    glEnd();
  84
  85    glFlush();
  86
  87    if (doubleBuffer) {
  88       glutSwapBuffers();
  89    }
  90 }
  91
  92 static GLenum Args(int argc, char **argv)
  93 {
  94    GLint i;
  95
  96    doubleBuffer = GL_FALSE;
  97
  98    for (i = 1; i < argc; i++) {
  99       if (strcmp(argv[i], "-sb") == 0) {
 100          doubleBuffer = GL_FALSE;
 101       } else if (strcmp(argv[i], "-db") == 0) {
 102          doubleBuffer = GL_TRUE;
 103       } else {
 104          fprintf(stderr, "%s (Bad option).\n", argv[i]);
 105          return GL_FALSE;
 106       }
 107    }
 108    return GL_TRUE;
 109 }
 110
 111 int main(int argc, char **argv)
 112 {
 113    GLenum type;
 114
 115    glutInit(&argc, argv);
 116
 117    if (Args(argc, argv) == GL_FALSE) {
 118       exit(1);
 119    }
 120
 121    glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 122
 123    type = GLUT_RGB | GLUT_ALPHA;
 124    type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 125    glutInitDisplayMode(type);
 126
 127    if (glutCreateWindow(*argv) == GL_FALSE) {
 128       exit(1);
 129    }
 130
 131    Init();
 132
 133    glutReshapeFunc(Reshape);
 134    glutKeyboardFunc(Key);
 135    glutDisplayFunc(Draw);
 136    glutMainLoop();
 137    return 0;
 138 }