Limiting framerate for use of PeekMessage()

[TheBeardedQuack]

Hey, I'm using PeekMessage in my windows loop but if unmanaged I'm told it can cause an awful lot of stress on the processor so I want to limit it with a simple FPS limit.

MSG msg;
while(true){
    while(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE) > 0){
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    if(msg.message == WM_QUIT)
        break;
    render_frame();
    limit_frames(FRAMELIMIT); //Macro defined globally
}
return msg.wParam;

void limit_frames(int fps){
	static clock_t time = 0;
	clock_t frameLimit = (1.0f/(float)fps);
	clock_t frame = (clock() - time) / CLOCKS_PER_SEC;
	if(frameLimit - frame > 0)
		Sleep((frameLimit - frame) * 1000.0);
	time = clock();
}

My problem is that the frame limit does not work unless FRAMELIMIT is defined as 1, no other number will work... Why?

[cire]

Well, if FRAMELIMIT is 2, what happens when you feed it to limit_frames?

It is used in: frameLimit = (1.0f/(float)fps);

So frameLimit = 1.0 / 2.0 = .5 converted to an integral type (which frameLimit is) = 0.

So, for any number greater than 1.0, frameLimit will be set to 0.

[Bourgond Aries]

I suggest using chrono:

void Fps::limit()
{
    t2 = std::chrono::high_resolution_clock::now();
    delay = std::chrono::duration_cast<std::chrono::nanoseconds>(t2 - t1).count();

    // We now know the delay, let's check it against our sleep time:
    if (delay < min_time)
		std::this_thread::sleep_for(std::chrono::nanoseconds(static_cast<int>(min_time - delay)));

    // Reset the starting timer.
    t1 = std::chrono::high_resolution_clock::now();
}

where min_time = 1E9f / fps;

Make this part of a class and you have a simple frame limiter.

[TheBeardedQuack]

Well I'm not.quite sure if I like the looks of that, I think.I'll just change the initiation to a double... Should fix my problem right?

(although this may not be the best method of frame limiting, u am only using it for learning purposes, ie just use that while I learn about other stuff for now)