ScrollManager constructor
parameters used to create this ScrollManager
Current scroll position
Last scroll deltas
Whether the ScrollManager should listen to the window scroll event or not
Callback to execute each time the scroll values change
Called by the scroll event listener
Updates the scroll manager X and Y scroll values as well as last X and Y deltas Internally called by the scroll event listener Could be called externally as well if the user wants to handle the scroll by himself
Destroy our scroll manager (just remove our event listner if it had been added previously)
Used to keep track of our scroll position, scroll deltas and trigger an onScroll callback.
Could either listen to the native scroll event or be hooked to any scroll (natural or virtual) scroll event