Determining direction of Mouse Movement

Hi,

Is there a way to determine the direction in which the mouse-cursor is moving (up/down)?

Kinda like a constant listener, or something.

I only know about the onMouseMove-function, but it doesnt seem to come with parameters for direction.

Maby there is something that can be done with the:

_ymouse

…parameter. Something similar to:

_ymouse ++;

…to indicate the mouse-cursor is moving downwards.

Thanks