[ODE] Programmer request (car physics)

[Jon Watte]

> Use dBodyGetVelocityAtPos (or something like this) to get the linear 
> velocity at the contact point. Then calculate the length.

The velocity at the contact point for a wheel with traction will 
always be 0 (almost by definition!). I use dBodyGetLinearVelocity() 
(for the center) and it seems to work OK.

Cheers,

			/ h+