MoveMap method with higher accuracy

MapControl/Avalonia/Map.Avalonia.cs

@@ -74,6 +74,7 @@ namespace MapControl
                 point.Pointer.Type == PointerType.Touch && HandleTouchPressed(point))
             {
                 point.Pointer.Capture(this);
+                SetTransformCenter(point.Position);
             }
 
             base.OnPointerPressed(e);
@@ -83,6 +84,7 @@ namespace MapControl
         {
             if (HandlePointerReleased(e.Pointer))
             {
+                EndMoveMap();
                 e.Pointer.Capture(null);
             }
 
@@ -91,7 +93,10 @@ namespace MapControl
 
         protected override void OnPointerCaptureLost(PointerCaptureLostEventArgs e)
         {
-            HandlePointerReleased(e.Pointer);
+            if (HandlePointerReleased(e.Pointer))
+            {
+                EndMoveMap();
+            }
 
             base.OnPointerCaptureLost(e);
         }
@@ -108,8 +113,8 @@ namespace MapControl
                 }
                 else if (e.Pointer.Type == PointerType.Mouse || ManipulationModes.HasFlag(ManipulationModes.Translate))
                 {
-                    TranslateMap(position - position1);
                     position1 = position;
+                    MoveMap(position);
                 }
             }
 

MapControl/Shared/MapBase.cs

@@ -278,15 +278,37 @@ namespace MapControl
         }
 
         /// <summary>
-        /// Changes the Center property according to the specified translation in view coordinates.
+        /// Moves the map by the difference of the specified position in view coordinates and a temporary
+        /// transform origin point that has been set before by a call to SetTransformCenter. Map movement
+        /// must be terminated by a call to EndMoveMap. MoveMap provides higher accuracy than TranslateMap.
         /// </summary>
-        public void TranslateMap(Point translation)
+        public void MoveMap(Point position)
+        {
+            if (transformCenter != null)
+            {
+                viewCenter = position;
+                UpdateTransform();
+            }
+        }
+
+        /// <summary>
+        /// Terminates map movement by the MoveMap method.
+        /// </summary>
+        public void EndMoveMap()
         {
             if (transformCenter != null)
             {
                 ResetTransformCenter();
                 UpdateTransform();
             }
+        }
+
+        /// <summary>
+        /// Changes the Center property according to the specified translation in view coordinates.
+        /// </summary>
+        public void TranslateMap(Point translation)
+        {
+            EndMoveMap();
 
             if (translation.X != 0d || translation.Y != 0d)
             {

MapControl/WPF/Map.WPF.cs

@@ -19,7 +19,6 @@ namespace MapControl
         public static readonly DependencyProperty ManipulationModeProperty =
             DependencyPropertyHelper.Register<Map, ManipulationModes>(nameof(ManipulationMode), ManipulationModes.Translate | ManipulationModes.Scale);
 
-        private Point? mousePosition;
         private double mouseWheelDelta;
 
         static Map()
@@ -73,28 +72,21 @@ namespace MapControl
         {
             if (Keyboard.Modifiers == ModifierKeys.None && CaptureMouse())
             {
-                mousePosition = e.GetPosition(this);
+                SetTransformCenter(e.GetPosition(this));
             }
         }
 
         private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
         {
-            if (mousePosition.HasValue)
+            EndMoveMap();
-            {
+            ReleaseMouseCapture();
-                mousePosition = null;
-                ReleaseMouseCapture();
-            }
         }
 
         private void OnMouseMove(object sender, MouseEventArgs e)
         {
-            if (mousePosition.HasValue)
+            if (e.LeftButton == MouseButtonState.Pressed)
             {
-                var position = e.GetPosition(this);
+                MoveMap(e.GetPosition(this));
-                var translation = new Point(position.X - mousePosition.Value.X, position.Y - mousePosition.Value.Y);
-                mousePosition = position;
-
-                TranslateMap(translation);
             }
         }
 

MapControl/WinUI/Map.WinUI.cs

@@ -24,7 +24,7 @@ namespace MapControl
         public static readonly DependencyProperty MouseWheelZoomDeltaProperty =
             DependencyPropertyHelper.Register<Map, double>(nameof(MouseWheelZoomDelta), 0.25);
 
-        private bool manipulationEnabled;
+        private bool mouseMoveEnabled;
         private double mouseWheelDelta;
 
         public Map()
@@ -53,7 +53,11 @@ namespace MapControl
 
         private void OnManipulationDelta(object sender, ManipulationDeltaRoutedEventArgs e)
         {
-            if (manipulationEnabled)
+            if (mouseMoveEnabled || e.Delta.Rotation == 0d && e.Delta.Scale == 1d)
+            {
+                MoveMap(e.Position);
+            }
+            else if (e.PointerDeviceType != PointerDeviceType.Mouse)
             {
                 TransformMap(e.Position, e.Delta.Translation, e.Delta.Rotation, e.Delta.Scale);
             }
@@ -61,14 +65,22 @@ namespace MapControl
 
         private void OnPointerPressed(object sender, PointerRoutedEventArgs e)
         {
-            manipulationEnabled = e.Pointer.PointerDeviceType != PointerDeviceType.Mouse ||
+            var point = e.GetCurrentPoint(this);
-                                  e.KeyModifiers == VirtualKeyModifiers.None &&
+
-                                  e.GetCurrentPoint(this).Properties.IsLeftButtonPressed;
+            mouseMoveEnabled = e.Pointer.PointerDeviceType == PointerDeviceType.Mouse &&
+                               e.KeyModifiers == VirtualKeyModifiers.None &&
+                               point.Properties.IsLeftButtonPressed;
+
+            if (mouseMoveEnabled || e.Pointer.PointerDeviceType != PointerDeviceType.Mouse)
+            {
+                SetTransformCenter(point.Position);
+            }
         }
 
         private void OnPointerReleased(object sender, PointerRoutedEventArgs e)
         {
-            manipulationEnabled = false;
+            mouseMoveEnabled = false;
+            EndMoveMap();
         }
 
         private void OnPointerWheelChanged(object sender, PointerRoutedEventArgs e)