The above code split the screen into 4 quarters, your entity will
move to left or right depends on your mouse pointer located on the
left side or right side of the screen. Also, the entity will move
forward/backward depends on your mouse pointer is on the upper or
lower part of the screen.

As I said it's not a perfect code, you have to modify it to get what you
need, or you have to be more specific about what you want to achieve.