The mouse isn't setting the angle, it's setting the target (or the location to arc to).
Right. My mistake, I meant to say arc.
To target a different object just replace "mousex" and "mousey" with the object's x and y.
The expression is where I'm stuck. I want to be able to throw the object with a controller button and have the arc's size only be based on how far the distance the ball being thrown is from the object being thrown to. For example:
01 ======= 02
The 01 represents the object the ball is being thrown from. 02 represents the object that will catch the ball. Because the distance is short the arc will be short.
01 ============================================= 02
^^^ In this one, since the distance is longer the arc will be higher.
Here is all I was able to get up to: