public TimeCoord? get_history ()
Retrieves the history of the device that this is for, as a list of time and coordinates.
The history includes positions that are not delivered as separate events to the application because they occurred in the same frame as this.
Note that only motion and scroll events record history, and motion events do it only if one of the mouse buttons is down.
a motion or scroll event
Return location for the length of the returned array
an array of time and coordinates