Multiply any number by negative one, and you get its opposite . For instance 100 times negative one is ˆ’ 100. On the other hand, ˆ’ 25 times negative one is 25 (positive 25). You can use this math trick to flip expressions to their opposites.
If you add an expression to Rotation and Pickwhip Position, the layer will rotate clockwise when you animate it moving to the right. What if you want it to move counterclockwise? Just multiply the expression by negative one. It will then read "position* ˆ’ 1", and the layer will rotate counterclockwise when you animate its position to the right.