Revert fling direction changes

Author: ben-milanko

lib/src/gestures/map_interactive_viewer.dart

@@ -78,7 +78,6 @@ class MapInteractiveViewerState extends State<MapInteractiveViewer>
   late double _lastRotation;
   late double _lastScale;
   late Offset _lastFocalLocal;
-  late Offset _prevFocalLocal;
   late LatLng _mapCenterStart;
   late double _mapZoomStart;
   late Offset _focalStartLocal;
@@ -540,8 +539,7 @@ class MapInteractiveViewerState extends State<MapInteractiveViewer>
 
     _mapZoomStart = _camera.zoom;
     _mapCenterStart = _camera.center;
-    _focalStartLocal =
-        _lastFocalLocal = _prevFocalLocal = details.localFocalPoint;
+    _focalStartLocal = _lastFocalLocal = details.localFocalPoint;
     _focalStartLatLng = _camera.offsetToCrs(_focalStartLocal);
 
     _dragStarted = false;
@@ -569,7 +567,6 @@ class MapInteractiveViewerState extends State<MapInteractiveViewer>
 
     _lastRotation = currentRotation;
     _lastScale = details.scale;
-    _prevFocalLocal = _lastFocalLocal;
     _lastFocalLocal = details.localFocalPoint;
   }
 
@@ -792,28 +789,13 @@ class MapInteractiveViewerState extends State<MapInteractiveViewer>
       return;
     }
 
-    // Use the tracked offset to determine direction instead of the velocity
-    // direction, which can be incorrect on web when the pointer leaves the
-    // window. Use the final segment direction to correctly handle curved
-    // gestures where the user changes direction during the drag.
-    final flingOffset = _focalStartLocal - _lastFocalLocal;
-    final finalSegment = _prevFocalLocal - _lastFocalLocal;
-    final finalSegmentDistance = finalSegment.distance;
-
-    // Use final segment direction if available, otherwise fall back to overall
-    // direction for edge cases where the final segment has no movement.
-    final Offset direction;
-    if (finalSegmentDistance > 0) {
-      direction = finalSegment / finalSegmentDistance;
-    } else {
-      final flingDistance = flingOffset.distance;
-      direction = flingOffset / flingDistance;
-    }
+    final direction = details.velocity.pixelsPerSecond / magnitude;
     final distance = (Offset.zero & _camera.nonRotatedSize).shortestSide;
 
+    final flingOffset = _focalStartLocal - _lastFocalLocal;
     _flingAnimation = Tween<Offset>(
       begin: flingOffset,
-      end: flingOffset + direction * distance,
+      end: flingOffset - direction * distance,
     ).animate(_flingController);
 
     _flingController