Reset right-click scrolling position when MapUI isn't the active control

Author: Rampastring

src/TSMapEditor/UI/MapUI.cs

@@ -548,16 +548,26 @@ public override void OnRightClick(InputEventArgs inputEventArgs)
         {
             inputEventArgs.Handled = true;
 
-            if (CursorAction != null && !isRightClickScrolling)
+            if (isRightClickScrolling)
+            {
+                StopRightClickScrolling();
+            }
+            else if (CursorAction != null)
             {
                 CursorAction = null;
             }
 
-            isRightClickScrolling = false;
+            StopRightClickScrolling();
 
             base.OnRightClick(inputEventArgs);
         }
 
+        private void StopRightClickScrolling()
+        {
+            isRightClickScrolling = false;
+            rightClickScrollInitPos = new Point(-1, -1);
+        }
+
         private MapTile CalculateBestTileUnderCursor()
         {
             Point2D cursorMapPoint = GetCursorMapPoint();
@@ -613,6 +623,10 @@ public override void Update(GameTime gameTime)
                     }
                 }
             }
+            else if (isRightClickScrolling)
+            {
+                StopRightClickScrolling();
+            }
 
             if (leftPressedDownOnControl && !Cursor.LeftDown)
                 leftPressedDownOnControl = false;