I'm programming a game where different types of objects will be sliding over different types of terrains (Top-down in two dimensions). At my current level of physics education we are given the coefficient of friction between any pairing of surfaces, but that's not practical for the amount of objects and terrains this game (will) have.
So my questions are,
- How do I find the force of friction between two objects, when I have their surface area and any other constants I need to add?
- How can I somewhat accurately simplify that to something on the order of $z=x*y+a*b$ ?
- I'd like to account for static vs kinetic friction, is there an easy way to do that?
Edit: failing any established approximations, if I make up some abitrary "grippiness" constant for all of the surfaces, what's the best way to combine them into a coefficient of friction?