Hello everyone. I am writing a space-shooter game in ImpactJS, and am running into an interesting problem. My game is laid out like this: I have a Player ship entity, an enemy that spawns every second, and flies off the screen, and Three scrolling background tile entities. My player ship entity can fire bullets, each themselves an entity.
At the absolute most, my application draws ~80 entities (the vast majority of them bullets - I have a very fast fire rate set up for debugging), but during normal running, only 6 or 7 entities are being drawn. However, I am experiencing significant lag (at times).
I am using Chrome Version 22.0.1229.79 m (it tells me it's up to date). When my browser is clamped to the side of a screen (like in fullscreen or dragged to the side in Windows 7) I get ~25 fps (an unacceptably slow rate). However, when my browser is smaller (even by a tiny amount) the fps immediately shoots up to 60fps. I've looked at the Impact debugger, and I'm seeing a large chunk of system lag eating up the processor when the browser is clamped, but when it's not clamped, System lag is nearly zero.
I've tested the screen size performance hit (note this is browser screen size, not the canvas size - the canvas remains the same size throughout) - between 0 -> 60% of the screen gives me 60fps, but any pixel above ~60% drives the fps down to 25.

Thanks for all your help!