Objects deactivate when they shouldn't

[tomaka]

I'm not a 100% sure about this, but it looks like objects with a (0,0) acceleration and a (x,0) movement (where abs(x) < 1) deactive themselves after a certain time (is_active returns false).

This means that having an object with a constant velocity of (-0.9, 0) is impossible for example.

I don't know whether this behavior is intended, but if so I think that the threshold should be configurable.

[sebcrozet]

You are right, any object with a total velocity magnitude bellow a hard-coded threshold of 1.0 will be frozen after some times.

I will make this threshold customizable on a per-rigid-body basis.