How to do the Geometry Wars gravity well effect
- by Mykel Stone
I'm not talking about the background grid here, I'm talking about the swirly particles going around the Gravity Wells! I've always liked the effect and decided it'd be a fun experiment to replicate it, I know GW uses Hooke's law all over the place, but I don't think the Particle-to-Well effect is done using springs, it looks like a distance-squared function.
Here is a video demonstrating the effect: http://www.youtube.com/watch?v=YgJe0YI18Fg
I can implement a spring or gravity effect on some particles just fine, that's easy. But I can't seem to get the effect to look similar to GWs effect. When I watch the effect in game it seems that the particles are emitted in bunches from the Well itself, they spiral outward around the center of the well, and eventually get flung outward, fall back towards the well, and repeat.
How does he make the particles spiral outward when spawned? How does he keep the particle bunches together when near the Well but spread away from each other when they're flung outward? How does he keep the particles so strongly attached to the Well?