mouse-position v2.1.0
mouse-position 
A module for getting the current mouse position on an element, designed for use in games and animations.
Usage
mouse = mousePosition(element, listener)
Start watching element for mousemove events. If you don't pass an element,
mouse will watch the entire browser window.
listener will attach the listener event to another element – helpful, for
example, to catch movement across a larger area but still receive positions
relative to element.
mouse0
The current horizontal position of the mouse, in pixels.
mouse1
The current vertical position of the mouse, in pixels.
mouse.prev0
The previous horizontal position of the mouse, in pixels.
mouse.prev1
The previous vertical position of the mouse, in pixels.
mouse.on('move', callback(event))
Called every time the mouse is moved anywhere on the targeted element.
mouse.flush()
Call this method at the end of each frame to update the prevX and prevY
values – you won't get mousemove events every frame, so if you don't update
this you might get incorrect values.
mouse.dispose()
Call this method to remove the internal mousemove event listener and any move callbacks on the mouse object.
License
MIT. See LICENSE.md for details.