Yeah, i think so too. In Vice City the most surprising thing to me was that they actually modelled tire temperature. it's probably a bit crude but i found it in

Yeah, i think so too. In Vice City the most surprising thing to me was that they actually modelled tire temperature. it's probably a bit crude but i found it interesting. As for the physics code, there's a big ProcessControl function all sorts of physical entities that does everything that has to happen to that entity each frame. some of it is physics, some not. My theory as to why varying timestep produces different results is that the physics calculations form some sort of differential equations whose solution depends on the timestep. That may be wrong but it makes sense to me at least. My approach to fixing it would be to log all sorts of forces applied to the physical objects each frame and log them so they can be compared. this is quite a bit of stuff to implement though so nobody has done it yet. if you or somebody is interested in that, we'd appreciate that a lot.