I am writing a 2D platformer. My walking / running is implemented by adding a horizontal velocity to the player. I found the player would stick to walls if he pushed against them while falling. I solved this by setting the friction for those objects to 0 using a Physicsl2D material. However, for quads that function as both walls and ground tiles, this means you will slide out of control on top of them. What is the standard way to have different friction on the side of an object and the top of an object? I realize I could use additional intersection tests to detect if the top, bottom, right side, or left side of the player is intersecting with the quad and adjust the friction of the quad at runtime. This just seems like a hack, though.