Hard to say if really, depends how it will be done. Most likely you would need to tell shader at which pixel is light, you can't really tell how much clients screen moved during character moving, you probably would need to sacrifice few colors to make it work for example red color of 255 would mean it's light (means you'll need to use 254 and less red in your icons) then blue and green colors could tell how far light goes, or what type it is.
Either way that's not postprocess effect. It's more like photon mapping to make it look good, or would need to draw objects, which light can't pass through in specific color, then make shader take it as obstacle, shader would return black image with alpha values in light areas, which would need to be drawn over almost final screen. It's too complicated to do with shader. It's slow because of network usage it has, client side processing can fix that, and many other things
|
||||||||||||||||||||||||||||
http://www.byond.com/developer/DarkCampainger/ StaticLightingGenerator