Prepares the drag gesture to use the provided screen coordinate as a pivot point. This function should be called each time when user starts a dragging action (e.g. by clicking on the map). The following dragging will be relative to the pivot.
Parameters
point
The pivot coordinate, measured in \link MapOptions#size platform pixels \endlink from top to bottom and from left to right.
open override fun dragStart(point: ScreenCoordinate)