[ODE] Damage!

[wesa aapro]

> You have to scavenge the collision penetration depth from the previous
> iteration - from actual collisions.  If you are doing your own collision

thanks, but this won't work since the penetration depth is random. in fact,
fast moving bullet-like objects will have a lot of penetration depth
variatons.
of course contact joints also have this kind of variations in the "forces"
they are giving to the bodies, but ode (with erp and cfm?) smoothens this
quite nicely.

and if two bodies of equal mass are stacked and third body of the same mass
is dropped over the top body, the penetration depth of bottom and top body
won't come any deeper since there already are some contact joints between
them. but the bottom body should also get some damage (at least the contact
joints with the floor and top body do lots of "work")

i think i need to know what happened inside the contact joints during last
iteration...?

wesa