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 #include <GL/glew.h>
  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    if (!glutExtensionSupported("GL_ARB_occlusion_query")) {
  43       fprintf(stderr, "Sorry, this program requires GL_ARB_occlusion_query\n");
  44       exit(1);
  45    }
  46
  47    fprintf(stderr, "GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
  48    fprintf(stderr, "GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
  49    fprintf(stderr, "GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
  50    fflush(stderr);
  51
  52     glClearColor(0.0, 0.0, 1.0, 0.0);
  53
  54    glGenQueriesARB(1, &OccQuery);
  55 }
  56
  57 static void Reshape(int width, int height)
  58 {
  59
  60     glViewport(0, 0, (GLint)width, (GLint)height);
  61
  62     glMatrixMode(GL_PROJECTION);
  63     glLoadIdentity();
  64     glOrtho(-1.0, 1.0, -1.0, 1.0, -0.5, 1000.0);
  65     glMatrixMode(GL_MODELVIEW);
  66 }
  67
  68 static void Key(unsigned char key, int x, int y)
  69 {
  70
  71     switch (key) {
  72       case 27:
  73         exit(1);
  74       default:
  75         break;
  76     }
  77
  78     glutPostRedisplay();
  79 }
  80
  81 static void Draw(void)
  82 {
  83    GLuint passed;
  84    GLint ready;
  85
  86    glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
  87
  88    glEnable(GL_DEPTH_TEST);
  89
  90    glBeginQueryARB(GL_SAMPLES_PASSED_ARB, OccQuery);
  91
  92    glBegin(GL_TRIANGLES);
  93    glColor3f(0,0,.7);
  94    glVertex3f( 0.9, -0.9, -30.0);
  95    glColor3f(.8,0,0);
  96    glVertex3f( 0.9,  0.9, -30.0);
  97    glColor3f(0,.9,0);
  98    glVertex3f(-0.9,  0.0, -30.0);
  99    glEnd();
 100
 101    glEndQueryARB(GL_SAMPLES_PASSED_ARB);
 102
 103    do {
 104       /* do useful work here, if any */
 105       glGetQueryObjectivARB(OccQuery, GL_QUERY_RESULT_AVAILABLE_ARB, &ready);
 106    } while (!ready);
 107    glGetQueryObjectuivARB(OccQuery, GL_QUERY_RESULT_ARB, &passed);
 108
 109    fprintf(stderr, " %d Fragments Visible\n", passed);
 110
 111    glFlush();
 112
 113    if (doubleBuffer) {
 114       glutSwapBuffers();
 115    }
 116 }
 117
 118 static GLenum Args(int argc, char **argv)
 119 {
 120     GLint i;
 121
 122     doubleBuffer = GL_FALSE;
 123
 124     for (i = 1; i < argc; i++) {
 125         if (strcmp(argv[i], "-sb") == 0) {
 126             doubleBuffer = GL_FALSE;
 127         } else if (strcmp(argv[i], "-db") == 0) {
 128             doubleBuffer = GL_TRUE;
 129         } else {
 130             fprintf(stderr, "%s (Bad option).\n", argv[i]);
 131             return GL_FALSE;
 132         }
 133     }
 134     return GL_TRUE;
 135 }
 136
 137 int main(int argc, char **argv)
 138 {
 139     GLenum type;
 140
 141     glutInit(&argc, argv);
 142
 143     if (Args(argc, argv) == GL_FALSE) {
 144         exit(1);
 145     }
 146
 147     glutInitWindowPosition(100, 0); glutInitWindowSize( 250, 250);
 148
 149     type = GLUT_RGB | GLUT_DEPTH;
 150     type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE;
 151     glutInitDisplayMode(type);
 152
 153     if (glutCreateWindow(*argv) == GL_FALSE) {
 154         exit(1);
 155     }
 156
 157     glewInit();
 158
 159     Init();
 160
 161     glutReshapeFunc(Reshape);
 162     glutKeyboardFunc(Key);
 163     glutDisplayFunc(Draw);
 164     glutMainLoop();
 165         return 0;
 166 }