doubleTapDragZoomChangeCalculator property
Calculates the zoom difference to apply to the initial zoom level when a user is performing a double-tap drag zoom gesture
verticalOffset is the vertical distance between the user's initial
pointer-down position and their current dragged position. camera may be
used, for example, to factor in the current zoom level.
The default calculator is defaultDoubleTapDragZoomChangeCalculator.
Implementation
final double Function(double verticalOffset, MapCamera camera)
doubleTapDragZoomChangeCalculator;