[ODE] solving penetrations "statically"

[Alen Ladavac]

> The main problem I find with the ODE solver is, as you have stated, the
> correction velocity adds momentum.  The most obvious example is this:
> Drop a sphere with bounce 0 from a large height.  It will still bounce.
> Worse, the bounce varies depending on how much interpentration occurs at
> the end of the time-step.  The joint code shows this very clearly: 
> target_vel = max(bounce, correcting_vel).  It can be minimised, but only
> by slowing down how much objects are pushed apart, so its a trade-off.

Actually, just putting a clamp to the correcting_vel with a max of
like 1m/s will make the unwanted bounces disappear for any practical
purpose. With a welcome side-effect that it will further increase the
stability of the system.

JM2C,
Alen