CollisionEffect iPhone game dev question

I'm interested in insight about what went into the game CollisionEffect for the iPhone from the developers perspective. It looks like an OpenGL ES game, with a very advanced particle system. The warping of the particles after nearby sphere is something I can't figure out. What is a good keyword for searching this flow effect for OpenGL implementations?

开发者_C百科

For example: http://www.youtube.com/watch?v=2wiBNCKJn8E

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I think it's nothing that difficult, if your talking about the blast effect. The particles left behind as a trail of the "sphere" travel at constant speed and fade out, but when the blast wave hits them, they are accelerated away from the center of the blast with great attenuation, so they slow down pretty fast. Cool effect though :)

EDIT

just saw the warping part :) it's also simple physics, the particles collide with the "sphere" and gain some velocity in the direction of their impulse after the collision. The drag is really high so their movement is attenuated pretty fast.

check this out:

http://en.wikipedia.org/wiki/Elastic_collision