Change the Cat Range variable and put your mouse within the circle. If you use this in a project be aware that the minimum size of the scanning line is 100 (that is Scratch's limit).
This is an experiment of mine. You can use this but please give credit. HOW IT WORKS: The line is constantly spinning around until it touches your mouse, or it rotates 360 degrees. When it touches your mouse, it will set a variable to the direction it is pointing in, and the cat will point in that direction.