view test/torturethread.c @ 1295:c3e36ac8a94c

Date: Sun, 6 Mar 2005 17:06:20 +0100 From: Per Inge Mathisen Subject: [SDL] Fullscreen refresh on win32 Windows has a terrible default for fullscreen 3D apps of 60mhz refresh rate. This can be fixed by the user by going into his driver's control panel and forcing the refresh rate higher. However, this not a very user friendly way about it, and in any case SDL contains no code that could figure out this that condition has afflicted the user. So the question is, could SDL fix this for the user? It is possible under Windows to request a higher refresh rate. The danger is of course that if the user has an old monitor, and you request a too high refresh rate, the monitor could be damaged. However, I believe there might be a way around that: Check before switching what refresh rate the user's desktop runs in, and if our fullscreen dimensions are equal or less than those of the desktop, use the higher refresh rate of 60 and the desktop rate. Since most users run their desktops in the same or higher resolution something sane, this should fix this problem for most users. Thoughts? An alternative is to add an SDL_GL_GetAttribute(SDL_GL_REFRESH_RATE) option so that programs can bitch at their users at their own convenience. - Per
author Sam Lantinga <slouken@libsdl.org>
date Mon, 30 Jan 2006 06:56:10 +0000
parents d93862a3d821
children 1dd8bf30a109
line wrap: on
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/* Simple test of the SDL threading code */

#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>

#include "SDL.h"
#include "SDL_thread.h"

#define NUMTHREADS 10

static char volatile time_for_threads_to_die[NUMTHREADS];

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void quit(int rc)
{
	SDL_Quit();
	exit(rc);
}

int SubThreadFunc(void *data) {
	while(! *(int volatile *)data) {
		; /*SDL_Delay(10);*/  /* do nothing */
	}
	return 0;
}

int ThreadFunc(void *data) {
	SDL_Thread *sub_threads[NUMTHREADS];
	int flags[NUMTHREADS];
	int i;
	int tid = (int ) data;

	fprintf(stderr, "Creating Thread %d\n", tid);

	for(i = 0; i < NUMTHREADS; i++) {
		flags[i] = 0;
		sub_threads[i] = SDL_CreateThread(SubThreadFunc, &flags[i]);
	}

	printf("Thread '%d' waiting for signal\n", tid);
	while(time_for_threads_to_die[tid] != 1) {
		; /* do nothing */
	}

	printf("Thread '%d' sending signals to subthreads\n", tid);
	for(i = 0; i <  NUMTHREADS; i++) {
		flags[i] = 1;
		SDL_WaitThread(sub_threads[i], NULL);
	}

	printf("Thread '%d' exiting!\n", tid);

	return 0;
}

int main(int argc, char *argv[])
{
	SDL_Thread *threads[NUMTHREADS];
	int i;

	/* Load the SDL library */
	if ( SDL_Init(0) < 0 ) {
		fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError());
		return(1);
	}

	signal(SIGSEGV, SIG_DFL);
	for(i = 0; i < NUMTHREADS; i++) {
		time_for_threads_to_die[i] = 0;
		threads[i] = SDL_CreateThread(ThreadFunc, (void *) i);
	
		if ( threads[i] == NULL ) {
			fprintf(stderr,
			"Couldn't create thread: %s\n", SDL_GetError());
			quit(1);
		}
	}

	for(i = 0; i < NUMTHREADS; i++) {
		time_for_threads_to_die[i] = 1;
	}

	for(i = NUMTHREADS-1; i >= 0; --i) {
		SDL_WaitThread(threads[i], NULL);
	}
	SDL_Quit();
	return(0);
}