Game optimisation - updateAfterEvent

[omniscient232]

Hello,

I read in a tutorial, that it is a good idea, to have flash running at 30fps, and haveing a timer that runs at 40fps that does:

function timerhandler(e:TimerEvent)
{
e.updateAfterEvent();
} 

I don't know why, but it seems to save about 10 fps in his example, over just setting the fps to 60. he gets 40fps with this updateAfterEvent, instead of 30fps, when setting the fps to 60, that the comp can't handle.

now first of all: Why does this help?

second of all: I have a variety of spaceships in my game, that move at completely different speeds. some go so slow, that you wouldn't notice the difference between 20fps and 60 fps, unless you study them accurately.
I figured, it woiuld be a good idea to render those slow spaceShips at lower fps, than the fast ones, for optimisation.
is there a way to set fps for them lower?

or maybe setting the movementTimer to a higher delay, will have the same effect? because they dont have to be redrawn, untill they move again?
will this have the same effect in optimisation?

thank you.

[tonypa]

I have not seen any proof that using timer would improve fps.

[omniscient232]

http://www.8bitrocket.com/newsdispla...newspage=10248,

but my most concern are the other questions.

[8bitjeff]

It's not just that it is a timer and the e.updateAfterEvent is fired off. There certainly are other ways to make a timer/optimized FPS. My timer is based around the concept of sleep and active rendering. By sleep/active rendering I am timing how long the actual game loops takes and then letting the processor sleep before it starts up the game loop again. This is much easier to accomplish in Java with threading (where I got the idea from). This, combined with the e.updateAfterEvent does a good job of smoothing out the framerate.

BUT, at frame rates above 40, the updateAfterEvent seems to cause some problems on some platforms and players. For that reason, the sleep based/active render game loop can be used without the updateAfterEvent.

Anyway, it is better to set the delta x and delta y of the different ships to different values rather than trying to run them at different framerates.

[Pazil]

8bitjeff, what you're talking about sounds really cool...can you please explain maybe a teensy bit more so I can steal your idea?

[8bitjeff]

Hey Pazil, I was referring to the link to my tutorial on Active rendering that Omniscient232 had posted:

Link

The idea centers around starting the timer with just 1 repetition (not a constant loop). You time the amount of milliseconds that it takes to run your game loop. If you have not used up all of the time available to the processor, it sleeps and lets to Flash player do things like garbage collection (well it does in Java at least). Then you start the timer again when you wait for the sleep time to finish.

All of the code and a lively discussion on some problems are fixes are in that above link.

[Pazil]

Good stuff!

I never knew about bitmapData locking/unlocking. In fact, I never even used bitmapData's (though I will be soon, as soon as I start making a game with my OpenFL library (it sucks right now though...)

Thanks! I'll give the article another read later. Right now I need to figure out some basic physics so that I can have a nice collision detection engine up'n'running!

P.

[omniscient232]

what do you mean change delta x and delta y? you mean the hspeed and vspeed?
i have differend hspeed and vspeed per enemytype. hspeed and vspeed means pixels change per second, in my app. i can then change the timerdelay of every ship.

I dont have one game loop,that does everything. i have a steptimer, for every ship. and by changing that stepTimer's delay I can choose the rate at which their x and y coordinates are changed.

This isn't very efficient is it?

Is it worth doing a redesign because of this? I think that graphics rendering is the bottleneck in my game right now.