Add middle mouse button drag scrolling

CnCNet · Dec 5, 2023 · b3239eb · b3239eb
1 parent 482ae3e
commit b3239eb
Showing 1 changed file with 42 additions and 5 deletions.
diff --git a/src/TSMapEditor/Rendering/MapView.cs b/src/TSMapEditor/Rendering/MapView.cs
@@ -64,6 +64,7 @@ public class MapView : XNAControl, ICursorActionTarget, IMutationTarget
     {
         private const float RightClickScrollRateDivisor = 64f;
         private const double ZoomStep = 0.1;
+        private const float DragScrollRateDivisor = 16f;
 
         private static Color[] MarbleMadnessTileHeightLevelColors = new Color[]
         {
@@ -168,6 +169,10 @@ public CursorAction CursorAction
         private bool isRightClickScrolling = false;
         private Point rightClickScrollInitPos = new Point(-1, -1);
 
+        private bool isDragScrolling = false;
+        private Point dragScrollInitPos = new Point(-1, -1);
+        private Vector2 dragScrollInitCameraPos = new Vector2(-1, -1);
+
         private Point lastClickedPoint;
 
         private List<GameObject> gameObjectsToRender = new List<GameObject>();
@@ -1089,10 +1094,13 @@ private void DrawRangeIndicator(Point2D cellCoords, double range, Color color)
 
         public override void OnMouseScrolled()
         {
-            if (Cursor.ScrollWheelValue > 0)
-                Camera.ZoomLevel += ZoomStep;
-            else
-                Camera.ZoomLevel -= ZoomStep;
+            if (!isDragScrolling)
+            {
+                if (Cursor.ScrollWheelValue > 0)
+                    Camera.ZoomLevel += ZoomStep;
+                else
+                    Camera.ZoomLevel -= ZoomStep;
+            }
 
             base.OnMouseScrolled();
         }
@@ -1205,13 +1213,35 @@ public override void OnMouseMove()
             // Right-click scrolling
             if (Cursor.RightDown)
             {
-                if (!isRightClickScrolling)
+                if (!isRightClickScrolling && !isDragScrolling)
                 {
                     isRightClickScrolling = true;
                     rightClickScrollInitPos = GetCursorPoint();
                     Camera.FloatTopLeftPoint = Camera.TopLeftPoint.ToXNAVector();
                 }
             }
+
+            // Drag scrolling
+            if (Cursor.MiddleDown)
+            {
+                if (!isRightClickScrolling)
+                {
+                    if (!isDragScrolling)
+                    {
+                        dragScrollInitPos = GetCursorPoint();
+                        dragScrollInitCameraPos = Camera.FloatTopLeftPoint;
+                        isDragScrolling = true;
+                    }
+                    else
+                    {
+                        var result = dragScrollInitPos - GetCursorPoint();
+                        float dragScrollRate = (float)((scrollRate / DragScrollRateDivisor) / Camera.ZoomLevel);
+
+                        Camera.FloatTopLeftPoint = new Vector2(dragScrollInitCameraPos.X + result.X * dragScrollRate,
+                           dragScrollInitCameraPos.Y + result.Y * dragScrollRate);
+                    }
+                }
+            }
         }
 
         public override void OnLeftClick()
@@ -1264,6 +1294,13 @@ public override void OnRightClick()
             base.OnRightClick();
         }
 
+        public override void OnMiddleClick()
+        {
+            isDragScrolling = false;
+
+            base.OnMiddleClick();
+        }
+
         public override void Update(GameTime gameTime)
         {
             // Make scroll rate independent of FPS