Just curious if anyone has any idea how to do an expression say on a moving ball that would collide with another ball, think pool balls. Just want the rotation to be influenced by x and y and possibly scale so that the rotation of the ball reacts to the direction the ball heads.

I have a 2D solve, but it might not be what you are looking for. It involves knowing the diameter of the ball measured in pixels. In the rotation.z of the axis that moves the ball, -360*(position.x/(diameter_of_the_ball*PI)). Scale changes need to be done on an axis above the motion axis. I developed this for x motion only, so you may need to play around to get y as well. It may need to triangulate and derive the distance from the hypotenuse, rather than just an x or y vector.

I do a demo in my “tips and Schtik” Logik Live from last December I think it’s about 45 minutes in