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/*
* Simple GLUT program to measure glClear() and glutSwapBuffers() speed.
* Brian Paul February 15, 1997 This file in public domain.
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <GL/glut.h>
static float MinPeriod = 2.0; /* 2 seconds */
static int ColorMode = GLUT_RGB;
static int Width = 400.0;
static int Height = 400.0;
static int Loops = 100;
static float ClearColor = 0.0;
static GLbitfield BufferMask = GL_COLOR_BUFFER_BIT;
static GLboolean SwapFlag = GL_FALSE;
static void Idle( void )
{
glutPostRedisplay();
}
static void Display( void )
{
double t0, t1;
double clearRate;
double pixelRate;
int i;
glClearColor( ClearColor, ClearColor, ClearColor, 0.0 );
ClearColor += 0.1;
if (ClearColor>1.0)
ClearColor = 0.0;
if (SwapFlag) {
t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
for (i=0;i<Loops;i++) {
glClear( BufferMask );
glutSwapBuffers();
}
glFinish();
t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
}
else {
t0 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
for (i=0;i<Loops;i++) {
glClear( BufferMask );
}
glFinish();
t1 = glutGet(GLUT_ELAPSED_TIME) * 0.001;
glutSwapBuffers();
}
/* NOTE: If clearspd doesn't map it's window immediately on
* starting, swaps will be istantaneous, so this will send Loops
* towards infinity. When a window is finally mapped, it may be
* minutes before the first call to glutSwapBuffers, making it look
* like there's a driver bug.
*/
if (t1-t0 < MinPeriod) {
/* Next time do more clears to get longer elapsed time */
Loops *= 2;
return;
}
clearRate = Loops / (t1-t0);
pixelRate = clearRate * Width * Height;
if (SwapFlag) {
printf("Rate: %d clears+swaps in %gs = %g clears+swaps/s %g pixels/s\n",
Loops, t1-t0, clearRate, pixelRate );
}
else {
printf("Rate: %d clears in %gs = %g clears/s %g pixels/s\n",
Loops, t1-t0, clearRate, pixelRate);
}
}
static void Reshape( int width, int height )
{
Width = width;
Height = height;
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glOrtho(0.0, width, 0.0, height, -1.0, 1.0);
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void Init( int argc, char *argv[] )
{
int i;
for (i=1; i<argc; i++) {
if (strcmp(argv[i],"+rgb")==0)
ColorMode = GLUT_RGB;
else if (strcmp(argv[i],"+ci")==0)
ColorMode = GLUT_INDEX;
else if (strcmp(argv[i],"-color")==0)
BufferMask = 0;
else if (strcmp(argv[i],"+depth")==0)
BufferMask |= GL_DEPTH_BUFFER_BIT;
else if (strcmp(argv[i],"+alpha")==0)
ColorMode = GLUT_RGB | GLUT_ALPHA;
else if (strcmp(argv[i],"+stencil")==0)
BufferMask |= GL_STENCIL_BUFFER_BIT;
else if (strcmp(argv[i],"+accum")==0)
BufferMask |= GL_ACCUM_BUFFER_BIT;
else if (strcmp(argv[i],"-width")==0) {
Width = atoi(argv[i+1]);
i++;
}
else if (strcmp(argv[i],"-height")==0) {
Height = atoi(argv[i+1]);
i++;
}
else if (strcmp(argv[i],"+swap")==0) {
SwapFlag = GL_TRUE;
}
else if (strcmp(argv[i],"-swap")==0) {
SwapFlag = GL_FALSE;
}
else
printf("Unknown option: %s\n", argv[i]);
}
if (ColorMode & GLUT_ALPHA)
printf("Mode: RGB + Alpha\n");
else if (ColorMode==GLUT_RGB)
printf("Mode: RGB\n");
else
printf("Mode: Color Index\n");
printf("SwapBuffers: %s\n", SwapFlag ? "yes" : "no" );
printf("Size: %d x %d\n", Width, Height);
printf("Buffers: ");
if (BufferMask & GL_COLOR_BUFFER_BIT) printf("color ");
if (BufferMask & GL_DEPTH_BUFFER_BIT) printf("depth ");
if (BufferMask & GL_STENCIL_BUFFER_BIT) printf("stencil ");
if (BufferMask & GL_ACCUM_BUFFER_BIT) printf("accum ");
printf("\n");
}
static void Help( const char *program )
{
printf("%s options:\n", program);
printf(" +rgb RGB mode\n");
printf(" +ci color index mode\n");
printf(" -color don't clear color buffer\n");
printf(" +alpha clear alpha buffer\n");
printf(" +depth clear depth buffer\n");
printf(" +stencil clear stencil buffer\n");
printf(" +accum clear accum buffer\n");
printf(" +swap also do SwapBuffers\n");
printf(" -swap don't do SwapBuffers\n");
}
int main( int argc, char *argv[] )
{
GLint mode;
printf("For options: %s -help\n", argv[0]);
Init( argc, argv );
glutInit( &argc, argv );
glutInitWindowSize( (int) Width, (int) Height );
glutInitWindowPosition( 0, 0 );
mode = ColorMode | GLUT_DOUBLE;
if (BufferMask & GL_STENCIL_BUFFER_BIT)
mode |= GLUT_STENCIL;
if (BufferMask & GL_ACCUM_BUFFER_BIT)
mode |= GLUT_ACCUM;
if (BufferMask & GL_DEPTH_BUFFER_BIT)
mode |= GLUT_DEPTH;
glutInitDisplayMode(mode);
glutCreateWindow( argv[0] );
if (argc==2 && strcmp(argv[1],"-help")==0) {
Help(argv[0]);
return 0;
}
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutDisplayFunc( Display );
glutIdleFunc( Idle );
glutMainLoop();
return 0;
}
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