Hi all, first post here.. I hope you guys can point me in the right direction. I am writing a multiplayer game and I need to interpolate through some position points in time that the client receives from other players. What I am doing right now is just using a Catmull-Rom interpolation to smooth out the changes in velocity and acceleration.. but I am not treating the objects as real physical entities. Due to some requirements in collision detection my system would really improve treating remote players as physical objects with mass, velocity, acceleration and forces applied on those. What I am looking here is a way to solve this: I have a starting point p0 and ending point p1, starting velocity v0 and ending velocity v1, what I want to do is to use forces (in discrete timesteps) to drive my object from p0 to p1 in a given time T ensuring that the velocities at the end points are correct. In other words, I would need some pointers to a physical explanation of the Catmull-Rom spline.. all I can come up with is that I will end up having 2 accelerations a1 and a2 to interpolate using a parameter V... I know it is messy, but any help would be apreciated.