fps capping

[EnEsCe]

Tried your pseudo code Neosano, and it was also not capping FPS at all. I set maxFPS to 75, it was going at 200+ FPS.

Code: (pascal) [Select]

var
  fpsStep = 1000 / maxFPS;
  fpsTimePassed = 0;
  fpsLastTime = 0;

begin
  fpsTimePassed := fpsTimePassed + timeGetTime() + fpsLastTime;
  fpsLastTime := timeGetTime();
  if (fpsTimePassed >= fpsStep) then begin
    RenderFrame;
    fpsTimePassed := fpsTimePassed - fpsStep;
  end;
end;

[-Major-]

what does the renderframe do enesce? does it only render the graphics in the frame, or does it make everything in the frame?

anyway, I guess you could maybe try a more mathematical way to do it.... probably with modulator ussage it should be possible...

lets say we want to limit fps to 93...

then take 1000/93 = X, make X an integer... then..

if (fpsCurrentTime mod X = 0) then
renderframe;
end;

or

if (fpsCurrentTime mod X = 1) then
renderframe;
end;

(mix around some with if/if not and 1/0)

the maths might be off and might not compile, just convert the stuff that is needed.


aaaah... but this might get really fucked up....

[Neosano]

ooops.. I screwed this post

[EnEsCe]

It still gives the exact same result Neosano, 200+ fps.
and timeGetTime() = http://msdn.microsoft.com/en-us/library/dd757629%28VS.85%29.aspx

At the moment I've got a better method, but still seems a tiny bit off. Capped at 75, getting 74-77 FPS, when capped at 120 getting 119-122. According to FRAPS.

[Neosano]

It still gives the exact same result Neosano, 200+ fps.
and timeGetTime() = http://msdn.microsoft.com/en-us/library/dd757629%28VS.85%29.aspx

At the moment I've got a better method, but still seems a tiny bit off. Capped at 75, getting 74-77 FPS, when capped at 120 getting 119-122. According to FRAPS.

ok. When game starts it should set fpsLastTime to timeGetTime()
Otherwise it's set to 0, which makes a lot of difference.

[-Major-]

It still gives the exact same result Neosano, 200+ fps.
and timeGetTime() = http://msdn.microsoft.com/en-us/library/dd757629%28VS.85%29.aspx

At the moment I've got a better method, but still seems a tiny bit off. Capped at 75, getting 74-77 FPS, when capped at 120 getting 119-122. According to FRAPS.

that little is probably because of fps drops and making stuff into integer tho...

however, what does renderframe do? is it only graphical drawing? make sure so the game doesn't update itself more than the capped fps.... otherwise the point of this is lost -.-

[EnEsCe]

Ok, when I do that it sits at 76-77 with a 75 cap; however at 120 cap it sits at 125 very steadily. 168 @ 160. 63 @ 60
@Major, yeah I agree its the decimal thing now. And RenderGame only renders the screen, all the time related events are outside the cap code.

[Neosano]

Ok, when I do that it sits at 76-77 with a 75 cap; however at 120 cap it sits at 125 very steadily. 168 @ 160. 63 @ 60
@Major, yeah I agree its the decimal thing now. And RenderGame only renders the screen, all the time related events are outside the cap code.

Well, sounds way better ^_^
maybe fpsLastTime is set to timeGetTime() in a wrong place? It must be set to it exactly when this algorithm starts. Well, I did what I can ^_^

Btw, Try 100 fps. maybe the problem is in dividing?

[-Major-]

Ok, when I do that it sits at 76-77 with a 75 cap; however at 120 cap it sits at 125 very steadily. 168 @ 160. 63 @ 60
@Major, yeah I agree its the decimal thing now. And RenderGame only renders the screen, all the time related events are outside the cap code.

so, then you should make the framecap code at the very base, so the game won't process any code unless a frame is supposed to be drawn~

[EnEsCe]

Btw, Try 100 fps. maybe the problem is in dividing?

100 sits perfectly at 100. So yes, it is something wrong with the dividing now.

[SyavX]

Why does (1000 / maxFPS) calculating every time?

Code: (Pascal) [Select]

var 
 maxFPS: byte = 0; 
 fpsLastFrame: DWORD = 0; 
 fpsCurrentTime: DWORD = 0; 
 fpsRenderInterval: WORD = 0;
 
// calculate render interval time after you read maxFPS value from .ini or smth
fpsRenderInterval := Round(1000 / maxFPS);

begin 
   fpsCurrentTime := timeGetTime(); 
   if (fpsCurrentTime - fpsLastFrame) >= fpsRenderInterval then begin 
     RenderFrame; 
     fpsLastFrame := fpsCurrentTime; 
   end; 
end;
The problem could be related to timeGetTime accuracy. Try to digg into timeBeginPeriod/timeEndPeriod direction or even QueryPerformanceTimer.

upd: oh, you probably did, coz of posted link to MSDN

[-Major-]

still~

the fps capping shouldn't only cap the drawed fps, but also all the processed data.

[biohazard]

still~

the fps capping shouldn't only cap the drawed fps, but also all the processed data.

nop, only drawed, ima quite sure thats how fps limit is supposed to work.

[-Major-]

nah... you wanna cap the updates per second.... otherwise you can't optimize your game -.-

[biohazard]

http://dev.koonsolo.com/7/dewitters-gameloop/

I think that Soldat already follow "Constant Game Speed with Maximum FPS" concept and cant be changed easier as like coding some lines.

[-Major-]

http://dev.koonsolo.com/7/dewitters-gameloop/

I think that Soldat already follow "Constant Game Speed with Maximum FPS" concept and cant be changed easier as like coding some lines.

hmm? can just put the update at the same place as renderframe.

[echo_trail]

Neosano, I will have you keep a civil tone.

[Neosano]

Btw, Try 100 fps. maybe the problem is in dividing?

100 sits perfectly at 100. So yes, it is something wrong with the dividing now.

Um.
fpsStep mustn't be an integer or byte.. something float is needed here.
same goes for fpsTimePassed.

2echo_trail
OKies ^_^

[SyavX]

Um.
fpsStep mustn't be an integer or byte.. something float is needed here.
same goes for fpsTimePassed.

timeGetTime returns an integer value (DWORD type), so... you are wrong.

[Neosano]

Um.
fpsStep mustn't be an integer or byte.. something float is needed here.
same goes for fpsTimePassed.

timeGetTime returns an integer value (DWORD type), so... you are wrong.

fpsStep=1000/maxFPS

1000/75=13.3333 .....Definitely I'm wrong...

next time read the code... PLEASE...