Algodoo

Idk how to make a two way portal such that I can pass any unscripted object through one or the other such that when it comes out the other portal it maintains its (angular and linear) velocity relative to the portal it entered.
So, as usual, I leave the challenge to you guys! Build away!
I want to be able to use this in a game of some kind and i will credit all who help.

Thanks!