progs/trivial/trifan-flat-unfilled-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 <GL/glut.h>
  29
  30
  31 #define CI_OFFSET_1 16
  32 #define CI_OFFSET_2 32
  33
  34
  35 GLenum doubleBuffer;
  36
  37 static void Init(void)
  38 {
  39    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  40    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  41    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  42    fflush(stderr);
  43
  44     glClearColor(0.0, 0.0, 1.0, 0.0);
  45 }
  46
  47 static void Reshape(int width, int height)
  48 {
  49
  50     glViewport(0, 0, (GLint)width, (GLint)height);
  51
  52     glMatrixMode(GL_PROJECTION);
  53     glLoadIdentity();
  54     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  55     glMatrixMode(GL_MODELVIEW);
  56 }
  57
  58 static void Key(unsigned char key, int x, int y)
  59 {
  60
  61     switch (key) {
  62       case 27:
  63         exit(1);
  64       default:
  65         break;
  66     }
  67
  68     glutPostRedisplay();
  69 }
  70
  71 static void Draw(void)
  72 {
  73    glClear(GL_COLOR_BUFFER_BIT);
  74    glShadeModel(GL_FLAT);
  75
  76    glPolygonMode(GL_FRONT, GL_LINE);
  77    glPolygonMode(GL_BACK, GL_LINE);
  78    glLineWidth(4.0);
  79
  80
  81    glBegin(GL_TRIANGLE_FAN);
  82    glColor3f(1,0,0);
  83    glVertex3f( 0, 0, -30.0);
  84    glColor3f(1,1,0);
  85    glVertex3f( 1.3,  1.1, -30.0);
  86    glColor3f(1,0,1);
  87    glVertex3f(-.9,  .9, -30.0);
  88    glColor3f(0,1,1);
  89    glVertex3f(-1.1,  -1.3, -30.0);
  90    glEnd();
  91
  92    glFlush();
  93
  94    if (doubleBuffer) {
  95       glutSwapBuffers();
  96    }
  97 }
  98
  99 static GLenum Args(int argc, char **argv)
 100 {
 101     GLint i;
 102
 103     doubleBuffer = GL_FALSE;
 104
 105     for (i = 1; i < argc; i++) {
 106         if (strcmp(argv[i], "-sb") == 0) {
 107             doubleBuffer = GL_FALSE;
 108         } else if (strcmp(argv[i], "-db") == 0) {
 109             doubleBuffer = GL_TRUE;
 110         } else {
 111             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 112             return GL_FALSE;
 113         }
 114     }
 115     return GL_TRUE;
 116 }
 117
 118 int main(int argc, char **argv)
 119 {
 120     GLenum type;
 121
 122     glutInit(&argc, argv);
 123
 124     if (Args(argc, argv) == GL_FALSE) {
 125         exit(1);
 126     }
 127
 128     glutInitWindowPosition(0, 0); glutInitWindowSize( 250, 250);
 129
 130     type = GLUT_RGB;
 131     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 132     glutInitDisplayMode(type);
 133
 134     if (glutCreateWindow(*argv) == GL_FALSE) {
 135         exit(1);
 136     }
 137
 138     Init();
 139
 140     glutReshapeFunc(Reshape);
 141     glutKeyboardFunc(Key);
 142     glutDisplayFunc(Draw);
 143     glutMainLoop();
 144         return 0;
 145 }