Problem with Collisions

[hussain.ali]

Hello guys,
I've been working on a game in which objects collide with each other then bounce perfectly (i.e the elasticity is 1). The problem is that when there are a few objects on the screen like say 3 or 4 everything works fine, but when the number of objects increase to say more than 5, the objects start running totally wild. i was wondering whether there's a way to control the forces/acceleration so that they do not go above a certain threshold, but i can't find any yet....

Any help would be greatly appreciated.

Thanks,
Hussain

[supertommy]

I think the documentation warns against using 1.0 or higher for elasticity. Does it work well if you set it to something close, but not quite 1.0? 0.95 or something?

[hussain.ali]

yup, i've set the elasticity to 0.9, it works fine when there are just 3 or 4 objects... but the problem is that when there are more objects they keep on colliding with each other more and more, and i think the forces acting on them start to increase so they start moving totally widely.

Is there a way in which we can limit the forced/velocity/acceleration to some certain value so that even if a lot of collisions occur, the velocity of the objects don't increase dramically...

thanks..

hussain

[ker]

you could check every objects rotational speed and velocity every frame and simply cut it off at a certain maximum. You'd have the most control over the outcome that way.

if you just want to control the velocity you could use a cpBodyVelocityFunc (http://code.google.com/p/chipmunk-physics/wiki/cpBody)