progs/trivial/tri-query.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 #define GL_GLEXT_PROTOTYPES
  29 #include <GL/glut.h>
  30
  31
  32
  33 #define CI_OFFSET_1 16
  34 #define CI_OFFSET_2 32
  35
  36 static GLuint OccQuery;
  37
  38 GLenum doubleBuffer;
  39
  40 static void Init(void)
  41 {
  42    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  43    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  44    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  45
  46     glClearColor(0.0, 0.0, 1.0, 0.0);
  47
  48    glGenQueriesARB(1, &OccQuery);
  49 }
  50
  51 static void Reshape(int width, int height)
  52 {
  53
  54     glViewport(0, 0, (GLint)width, (GLint)height);
  55
  56     glMatrixMode(GL_PROJECTION);
  57     glLoadIdentity();
  58     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  59     glMatrixMode(GL_MODELVIEW);
  60 }
  61
  62 static void Key(unsigned char key, int x, int y)
  63 {
  64
  65     switch (key) {
  66       case 27:
  67         exit(1);
  68       default:
  69         return;
  70     }
  71
  72     glutPostRedisplay();
  73 }
  74
  75 static void Draw(void)
  76 {
  77    GLuint passed;
  78    GLint ready;
  79
  80    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  81
  82    glEnable(GL_DEPTH_TEST);
  83
  84    glBeginQueryARB(GL_SAMPLES_PASSED_ARB, OccQuery);
  85
  86    glBegin(GL_TRIANGLES);
  87    glColor3f(0,0,.7);
  88    glVertex3f( 0.9, -0.9, -30.0);
  89    glColor3f(.8,0,0);
  90    glVertex3f( 0.9,  0.9, -30.0);
  91    glColor3f(0,.9,0);
  92    glVertex3f(-0.9,  0.0, -30.0);
  93    glEnd();
  94
  95    glEndQueryARB(GL_SAMPLES_PASSED_ARB);
  96
  97    do {
  98       /* do useful work here, if any */
  99       glGetQueryObjectivARB(OccQuery, GL_QUERY_RESULT_AVAILABLE_ARB, &ready);
 100    } while (!ready);
 101    glGetQueryObjectuivARB(OccQuery, GL_QUERY_RESULT_ARB, &passed);
 102
 103    fprintf(stderr, " %d Fragments Visible\n", passed);
 104
 105    glFlush();
 106
 107    if (doubleBuffer) {
 108       glutSwapBuffers();
 109    }
 110 }
 111
 112 static GLenum Args(int argc, char **argv)
 113 {
 114     GLint i;
 115
 116     doubleBuffer = GL_FALSE;
 117
 118     for (i = 1; i < argc; i++) {
 119         if (strcmp(argv[i], "-sb") == 0) {
 120             doubleBuffer = GL_FALSE;
 121         } else if (strcmp(argv[i], "-db") == 0) {
 122             doubleBuffer = GL_TRUE;
 123         } else {
 124             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 125             return GL_FALSE;
 126         }
 127     }
 128     return GL_TRUE;
 129 }
 130
 131 int main(int argc, char **argv)
 132 {
 133     GLenum type;
 134
 135     glutInit(&argc, argv);
 136
 137     if (Args(argc, argv) == GL_FALSE) {
 138         exit(1);
 139     }
 140
 141     glutInitWindowPosition(100, 0); glutInitWindowSize( 250, 250);
 142
 143     type = GLUT_RGB | GLUT_DEPTH;
 144     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 145     glutInitDisplayMode(type);
 146
 147     if (glutCreateWindow("First Tri") == GL_FALSE) {
 148         exit(1);
 149     }
 150
 151     Init();
 152
 153     glutReshapeFunc(Reshape);
 154     glutKeyboardFunc(Key);
 155     glutDisplayFunc(Draw);
 156     glutMainLoop();
 157         return 0;
 158 }