progs/demos/clearspd.c

   1 /* $Id: clearspd.c,v 1.3 2000/12/07 21:50:39 brianp Exp $ */
   2
   3 /*
   4  * Simple GLUT program to measure glClear() and glutSwapBuffers() speed.
   5  * Brian Paul  February 15, 1997  This file in public domain.
   6  */
   7
   8 /*
   9  * $Log: clearspd.c,v $
  10  * Revision 1.3  2000/12/07 21:50:39  brianp
  11  * call glFinish() before getting t1 time
  12  *
  13  * Revision 1.2  2000/04/10 16:25:15  brianp
  14  * fixed visual selection and reporting results
  15  *
  16  * Revision 1.1.1.1  1999/08/19 00:55:40  jtg
  17  * Imported sources
  18  *
  19  * Revision 3.3  1999/03/28 18:18:33  brianp
  20  * minor clean-up
  21  *
  22  * Revision 3.2  1999/03/18 08:16:34  joukj
  23  *
  24  *     cmpstr needs string.h to included to avoid warnings
  25  *
  26  * Revision 3.1  1998/06/29 02:38:30  brianp
  27  * removed unneeded includes
  28  *
  29  * Revision 3.0  1998/02/14 18:42:29  brianp
  30  * initial rev
  31  *
  32  */
  33
  34
  35 #include <stdio.h>
  36 #include <stdlib.h>
  37 #include <math.h>
  38 #include <string.h>
  39 #include <GL/glut.h>
  40
  41
  42 static float MinPeriod = 2.0;   /* 2 seconds */
  43 static int ColorMode = GLUT_RGB;
  44 static int Width = 400.0;
  45 static int Height = 400.0;
  46 static int Loops = 100;
  47 static float ClearColor = 0.0;
  48 static GLbitfield BufferMask = GL_COLOR_BUFFER_BIT;
  49 static GLboolean SwapFlag = GL_FALSE;
  50
  51
  52
  53 static void Idle( void )
  54 {
  55    glutPostRedisplay();
  56 }
  57
  58
  59 static void Display( void )
  60 {
  61    double t0, t1;
  62    double clearRate;
  63    double pixelRate;
  64    int i;
  65
  66    glClearColor( ClearColor, ClearColor, ClearColor, 0.0 );
  67    ClearColor += 0.1;
  68    if (ClearColor>1.0)
  69       ClearColor = 0.0;
  70
  71    if (SwapFlag) {
  72       t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
  73       for (i=0;i<Loops;i++) {
  74          glClear( BufferMask );
  75          glutSwapBuffers();
  76       }
  77       glFinish();
  78       t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
  79    }
  80    else {
  81       t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
  82       for (i=0;i<Loops;i++) {
  83          glClear( BufferMask );
  84       }
  85       glFinish();
  86       t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
  87       glutSwapBuffers();
  88    }
  89
  90    if (t1-t0 < MinPeriod) {
  91       /* Next time do more clears to get longer elapsed time */
  92       Loops *= 2;
  93       return;
  94    }
  95
  96    clearRate = Loops / (t1-t0);
  97    pixelRate = clearRate * Width * Height;
  98    if (SwapFlag) {
  99       printf("Rate: %d clears+swaps in %gs = %g clears+swaps/s   %g pixels/s\n",
 100              Loops, t1-t0, clearRate, pixelRate );
 101    }
 102    else {
 103       printf("Rate: %d clears in %gs = %g clears/s   %g pixels/s\n",
 104              Loops, t1-t0, clearRate, pixelRate);
 105    }
 106 }
 107
 108
 109 static void Reshape( int width, int height )
 110 {
 111    Width = width;
 112    Height = height;
 113    glViewport( 0, 0, width, height );
 114    glMatrixMode( GL_PROJECTION );
 115    glLoadIdentity();
 116    glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
 117    glMatrixMode( GL_MODELVIEW );
 118    glLoadIdentity();
 119 }
 120
 121
 122 static void Key( unsigned char key, int x, int y )
 123 {
 124    (void) x;
 125    (void) y;
 126    switch (key) {
 127       case 27:
 128          exit(0);
 129          break;
 130    }
 131    glutPostRedisplay();
 132 }
 133
 134
 135 static void Init( int argc, char *argv[] )
 136 {
 137    int i;
 138    for (i=1; i<argc; i++) {
 139       if (strcmp(argv[i],"+rgb")==0)
 140          ColorMode = GLUT_RGB;
 141       else if (strcmp(argv[i],"+ci")==0)
 142          ColorMode = GLUT_INDEX;
 143       else if (strcmp(argv[i],"-color")==0)
 144          BufferMask = 0;
 145       else if (strcmp(argv[i],"+depth")==0)
 146          BufferMask |= GL_DEPTH_BUFFER_BIT;
 147       else if (strcmp(argv[i],"+alpha")==0)
 148          ColorMode = GLUT_RGB | GLUT_ALPHA;
 149       else if (strcmp(argv[i],"+stencil")==0)
 150          BufferMask |= GL_STENCIL_BUFFER_BIT;
 151       else if (strcmp(argv[i],"+accum")==0)
 152          BufferMask |= GL_ACCUM_BUFFER_BIT;
 153       else if (strcmp(argv[i],"-width")==0) {
 154          Width = atoi(argv[i+1]);
 155          i++;
 156       }
 157       else if (strcmp(argv[i],"-height")==0) {
 158          Height = atoi(argv[i+1]);
 159          i++;
 160       }
 161       else if (strcmp(argv[i],"+swap")==0) {
 162          SwapFlag = GL_TRUE;
 163       }
 164       else if (strcmp(argv[i],"-swap")==0) {
 165          SwapFlag = GL_FALSE;
 166       }
 167       else
 168          printf("Unknown option: %s\n", argv[i]);
 169    }
 170
 171    if (ColorMode & GLUT_ALPHA)
 172       printf("Mode:  RGB + Alpha\n");
 173    else if (ColorMode==GLUT_RGB)
 174       printf("Mode:  RGB\n");
 175    else
 176       printf("Mode:  Color Index\n");
 177    printf("SwapBuffers: %s\n", SwapFlag ? "yes" : "no" );
 178    printf("Size: %d x %d\n", Width, Height);
 179    printf("Buffers: ");
 180    if (BufferMask & GL_COLOR_BUFFER_BIT)  printf("color ");
 181    if (BufferMask & GL_DEPTH_BUFFER_BIT)  printf("depth ");
 182    if (BufferMask & GL_STENCIL_BUFFER_BIT)  printf("stencil ");
 183    if (BufferMask & GL_ACCUM_BUFFER_BIT)  printf("accum ");
 184    printf("\n");
 185 }
 186
 187
 188 static void Help( const char *program )
 189 {
 190    printf("%s options:\n", program);
 191    printf("  +rgb       RGB mode\n");
 192    printf("  +ci        color index mode\n");
 193    printf("  -color     don't clear color buffer\n");
 194    printf("  +alpha     clear alpha buffer\n");
 195    printf("  +depth     clear depth buffer\n");
 196    printf("  +stencil   clear stencil buffer\n");
 197    printf("  +accum     clear accum buffer\n");
 198    printf("  +swap      also do SwapBuffers\n");
 199    printf("  -swap      don't do SwapBuffers\n");
 200 }
 201
 202
 203 int main( int argc, char *argv[] )
 204 {
 205    GLint mode;
 206
 207    printf("For options:  %s -help\n", argv[0]);
 208
 209    Init( argc, argv );
 210
 211    glutInit( &argc, argv );
 212    glutInitWindowSize( (int) Width, (int) Height );
 213    glutInitWindowPosition( 0, 0 );
 214
 215    mode = ColorMode | GLUT_DOUBLE;
 216    if (BufferMask & GL_STENCIL_BUFFER_BIT)
 217       mode |= GLUT_STENCIL;
 218    if (BufferMask & GL_ACCUM_BUFFER_BIT)
 219       mode |= GLUT_ACCUM;
 220    if (BufferMask & GL_DEPTH_BUFFER_BIT)
 221       mode |= GLUT_DEPTH;
 222
 223    glutInitDisplayMode(mode);
 224
 225    glutCreateWindow( argv[0] );
 226
 227    if (argc==2 && strcmp(argv[1],"-help")==0) {
 228       Help(argv[0]);
 229       return 0;
 230    }
 231
 232    glutReshapeFunc( Reshape );
 233    glutKeyboardFunc( Key );
 234    glutDisplayFunc( Display );
 235    glutIdleFunc( Idle );
 236
 237    glutMainLoop();
 238    return 0;
 239 }