Thread: Handling FPS / time...

Hello, so this is about handling frames per second.
I know *logically* how to handle them, but the problem
is being accurate with thw win32 function named "Sleep()".

You know, when you want to handle fps you just check for times
differences between frames and just need to Sleep() for the amount of time remaining before you reach your actual framerate...

So if I want 60fps, I'll have to do 1000ms/60fps = ~17ms
So I have to use Sleep(17 - time elapsed)...

Here the problem is the way Windows handle time for every running application. You know, like it will give ~10ms of execution for each opened program in order to look like everything is running at the same time... So the preoblem is that if you need to Sleep() for let say only one millisecond, its possible that you'll be waiting in the end for about 11 ms because of the time given to each program... You get what I mean?

So I want to know if there was something, function, that could tell to the CPU: I really want to wait 1ms, not more!
Or some other function that would make it's running process more important, so that the CPU would almost only work for this appl and not on the other, like it could maybe run it for a second before switching to another app...

You get the idea? I'm sure there's a solution to that, because our actual video games have no problem handling fps!

Slymaelstrom, I though I told in first place how I already knew that you should Sleep() once the rendering is done... I know that! thanks anyway

Lightatdawn, I had never thought about this! I like your idea! Its a good idea to prepare next frames while you still can...!

I must add that in the mean while I found a solution to fps... you can also change the global speed for every thing in your game depending on the framerate. But I suppose that in 3d animations, it can get a little tricky...

well, actually I am working on a game , but it's in 2D! (SDL)
It's certain that there are less lines of codes an more fps, but...
I found some problem even with my speed changing motion thing:

on 2D games, (from tests...) if you have a speed variable at 1.000
when you have 60fps, it sure won't really affect the calculations, but if your game is really optimised and you reach some 2500fps, (2D), then the calculation of motion will be less accurate depending on the floating point precision of that variable:
var = 1 when 60fps,
var = 60/2500 when 2500fps (could be some complex number...)

so we could opt for a variable of type "double", but in the end, after allllll our hard work, we will lose the gained fps because of the high floating-point precision calculation time

In an other order of idea , I don't think that (yet) we can make some games with high per-particle effects and collisions, but in the near future, maybe we'll have no limit to adding details in scenes without abusing of our lil' computers memory!

Thanks again