Disable Bouncing of Box.

thanhquan1512

My simple box has restitution parameter set to 0. But still when it falls from high it bounces from ground and other boxes (ground is a static obj with restitution = 0)

The same problem was posted here but I don't know how to modify b2MixRestitution with Gideros:

http://www.box2d.org/forum/viewtopic.php?f=4&t=5662

Please help me, thank you

ar2rsawseen

From my understanding what b2MixRestitution does is decides which restitution to use, and by default it takes max restitution from both colliding objects (or mixes them somehow). If your box has restitution 0 and ground has restitution 0, setting b2MixRestitution won't change anything. Then the problem lies somewhere else.

Increasing density of object or maybe even friction might help.

And of course if all fails, you can try some drastical solutions, like creating a magnet from floor

thanhquan1512

@ar2rsawseen: Thank you so much.

As in box2D's documentation: "set restitution = 0 does not guarantee that there is no bouncing". Actually I don't know where is the problem

Edit: Got it, after many tries I decide to slow down box & avoid bouncing, use:
boxBody:setLinearDamping(number)

ar2rsawseen

@thanhquan1512 I've actually found out the way of overwriting the restitution.

Set up the pre_solve event and inside it, retrieve contact object and modify it's restitution like this:

function scene:onPreSolve(e) local contact = e.contact contact:setRestitution(0) end

Don't know if it will solve your problem, but maybe it'll be useful

atilim

I think @ar2rsawseen's solution is great. But when both box and ground have restitution = 0, it shouldn't bounce at all.