dragUpdated method
To be called when an ongoing drag movement updates.
Implementation
void dragUpdated(MapEventSource source, Offset offset) {
final oldCenterPt = camera.project(camera.center);
final newCenterPt = oldCenterPt + offset.toPoint();
final newCenter = camera.unproject(newCenterPt);
moveRaw(
newCenter,
camera.zoom,
hasGesture: true,
source: source,
);
}