Freeze select box buttons position on press

osu.Game/Screens/Edit/Compose/Components/SelectionBox.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Linq;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
@@ -284,8 +285,12 @@ private SelectionBoxButton addButton(IconUsage icon, string tooltip, Action acti
                 Action = action
             };
 
+            button.OperationStarted += freezeButtonPosition;
+            button.HoverLost += unfreezeButtonPosition;
+
             button.OperationStarted += operationStarted;
             button.OperationEnded += operationEnded;
+
             buttons.Add(button);
 
             return button;
@@ -357,9 +362,35 @@ private void operationStarted()
                 OperationStarted?.Invoke();
         }
 
-        private void ensureButtonsOnScreen()
+        private Vector2? frozenButtonsPosition;
+
+        private void freezeButtonPosition()
+        {
+            frozenButtonsPosition = buttons.ScreenSpaceDrawQuad.TopLeft;
+        }
+
+        private void unfreezeButtonPosition()
         {
-            buttons.Position = Vector2.Zero;
+            if (frozenButtonsPosition != null)
+            {
+                frozenButtonsPosition = null;
+                ensureButtonsOnScreen(true);
+            }
+        }
+
+        private void ensureButtonsOnScreen(bool animated = false)
+        {
+            if (frozenButtonsPosition != null)
+            {
+                buttons.Anchor = Anchor.TopLeft;
+                buttons.Origin = Anchor.TopLeft;
+
+                buttons.Position = ToLocalSpace(frozenButtonsPosition.Value) - new Vector2(button_padding);
+                return;
+            }
+
+            if (!animated && buttons.Transforms.Any())
+                return;
 
             var thisQuad = ScreenSpaceDrawQuad;
 
@@ -374,24 +405,51 @@ private void ensureButtonsOnScreen()
 
             float minHeight = buttons.ScreenSpaceDrawQuad.Height;
 
+            Anchor targetAnchor;
+            Anchor targetOrigin;
+            Vector2 targetPosition = Vector2.Zero;
+
             if (topExcess < minHeight && bottomExcess < minHeight)
             {
-                buttons.Anchor = Anchor.BottomCentre;
-                buttons.Origin = Anchor.BottomCentre;
-                buttons.Y = Math.Min(0, ToLocalSpace(Parent!.ScreenSpaceDrawQuad.BottomLeft).Y - DrawHeight);
+                targetAnchor = Anchor.BottomCentre;
+                targetOrigin = Anchor.BottomCentre;
+                targetPosition.Y = Math.Min(0, ToLocalSpace(Parent!.ScreenSpaceDrawQuad.BottomLeft).Y - DrawHeight);
             }
             else if (topExcess > bottomExcess)
             {
-                buttons.Anchor = Anchor.TopCentre;
-                buttons.Origin = Anchor.BottomCentre;
+                targetAnchor = Anchor.TopCentre;
+                targetOrigin = Anchor.BottomCentre;
             }
             else
             {
-                buttons.Anchor = Anchor.BottomCentre;
-                buttons.Origin = Anchor.TopCentre;
+                targetAnchor = Anchor.BottomCentre;
+                targetOrigin = Anchor.TopCentre;
             }
 
-            buttons.X += ToLocalSpace(thisQuad.TopLeft - new Vector2(Math.Min(0, leftExcess)) + new Vector2(Math.Min(0, rightExcess))).X;
+            targetPosition.X += ToLocalSpace(thisQuad.TopLeft - new Vector2(Math.Min(0, leftExcess)) + new Vector2(Math.Min(0, rightExcess))).X;
+
+            if (animated)
+            {
+                var originalPosition = ToLocalSpace(buttons.ScreenSpaceDrawQuad.TopLeft);
+
+                buttons.Origin = targetOrigin;
+                buttons.Anchor = targetAnchor;
+                buttons.Position = targetPosition;
+
+                var newPosition = ToLocalSpace(buttons.ScreenSpaceDrawQuad.TopLeft);
+
+                var delta = newPosition - originalPosition;
+
+                buttons.Position -= delta;
+
+                buttons.MoveTo(targetPosition, 300, Easing.OutQuint);
+            }
+            else
+            {
+                buttons.Anchor = targetAnchor;
+                buttons.Origin = targetOrigin;
+                buttons.Position = targetPosition;
+            }
         }
     }
 }

osu.Game/Screens/Edit/Compose/Components/SelectionBoxButton.cs

@@ -21,6 +21,8 @@ public sealed partial class SelectionBoxButton : SelectionBoxControl, IHasToolti
 
         public Action? Action;
 
+        public event Action? HoverLost;
+
         public SelectionBoxButton(IconUsage iconUsage, string tooltip)
         {
             this.iconUsage = iconUsage;
@@ -61,6 +63,13 @@ protected override void UpdateHoverState()
             icon.FadeColour(!IsHeld && IsHovered ? Color4.White : Color4.Black, TRANSFORM_DURATION, Easing.OutQuint);
         }
 
+        protected override void OnHoverLost(HoverLostEvent e)
+        {
+            base.OnHoverLost(e);
+
+            HoverLost?.Invoke();
+        }
+
         public LocalisableString TooltipText { get; }
     }
 }