onPointerSignal method

Implementation

void onPointerSignal(PointerSignalEvent pointerSignal) {
  // Handle mouse scroll events if the enableScrollWheel parameter is enabled
  if (pointerSignal is PointerScrollEvent &&
      mapState.options.enableScrollWheel &&
      pointerSignal.scrollDelta.dy != 0) {
    // Prevent scrolling of parent/child widgets simultaneously. See
    // [PointerSignalResolver] documentation for more information.
    GestureBinding.instance.pointerSignalResolver.register(pointerSignal,
        (pointerSignal) {
      pointerSignal as PointerScrollEvent;

      final minZoom = mapState.options.minZoom ?? 0.0;
      final maxZoom = mapState.options.maxZoom ?? double.infinity;
      final newZoom = (mapState.zoom -
              pointerSignal.scrollDelta.dy *
                  mapState.options.scrollWheelVelocity)
          .clamp(minZoom, maxZoom);
      // Calculate offset of mouse cursor from viewport center
      final List<dynamic> newCenterZoom = _getNewEventCenterZoomPosition(
          _offsetToPoint(pointerSignal.localPosition), newZoom);

      // Move to new center and zoom level
      mapState.move(newCenterZoom[0] as LatLng, newCenterZoom[1] as double,
          source: MapEventSource.scrollWheel);
    });
  }
}