Powder Physics Games

Does anyone have any experience with this sort of thing?

I'm talking about applets like this http://dan-ball.jp/en/j开发者_JAVA百科avagame/dust/

I'm really interested in how they work, it seems more like fluid-dynamics than regular game physics. Does anyone know any open source variations, or any hints on how they might work? I think it would be really fun and challenging to work on something like this, but I'm not sure where to start researching...

Thanks :)

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One place you can look is at Processing.org. There you can find some examples of those types of programs, including the source and some decent explanations. It is java-like, but not entirely java.

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I've played around with both phys2d and jbox2d. I find Phys2d is easier to use.