Add transition for selecting a beatmap

osu.Game/Screens/SelectV2/BeatmapCarousel.cs

@@ -10,6 +10,7 @@ using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Pooling;
+using osu.Framework.Utils;
 using osu.Game.Beatmaps;
 using osu.Game.Database;
 using osu.Game.Graphics.UserInterface;
@@ -260,6 +261,32 @@ namespace osu.Game.Screens.SelectV2
 
         #endregion
 
+        #region Animation
+
+        /// <summary>
+        /// Moves non-selected beatmaps to the right, hiding off-screen.
+        /// </summary>
+        public bool VisuallyFocusSelected { get; set; }
+
+        private float selectionFocusOffset;
+
+        protected override void Update()
+        {
+            base.Update();
+
+            selectionFocusOffset = (float)Interpolation.DampContinuously(selectionFocusOffset, VisuallyFocusSelected ? 300 : 0, 100, Time.Elapsed);
+
+            foreach (var panel in Scroll.Panels)
+            {
+                var c = (ICarouselPanel)panel;
+
+                if (!c.Selected.Value)
+                    panel.X += selectionFocusOffset;
+            }
+        }
+
+        #endregion
+
         #region Filtering
 
         public FilterCriteria Criteria { get; private set; } = new FilterCriteria();

osu.Game/Screens/SelectV2/Carousel.cs

@@ -75,7 +75,7 @@ namespace osu.Game.Screens.SelectV2
         /// <summary>
         /// The number of items currently actualised into drawables.
         /// </summary>
-        public int VisibleItems => scroll.Panels.Count;
+        public int VisibleItems => Scroll.Panels.Count;
 
         /// <summary>
         /// The currently selected model. Generally of type T.
@@ -185,7 +185,7 @@ namespace osu.Game.Screens.SelectV2
         /// <param name="item">The item to find a related drawable representation.</param>
         /// <returns>The drawable representation if it exists.</returns>
         protected Drawable? GetMaterialisedDrawableForItem(CarouselItem item) =>
-            scroll.Panels.SingleOrDefault(p => ((ICarouselPanel)p).Item == item);
+            Scroll.Panels.SingleOrDefault(p => ((ICarouselPanel)p).Item == item);
 
         /// <summary>
         /// When a user is traversing the carousel via group selection keys, assert whether the item provided is a valid target.
@@ -222,11 +222,11 @@ namespace osu.Game.Screens.SelectV2
 
         #region Initialisation
 
-        private readonly CarouselScrollContainer scroll;
+        protected readonly CarouselScrollContainer Scroll;
 
         protected Carousel()
         {
-            InternalChild = scroll = new CarouselScrollContainer
+            InternalChild = Scroll = new CarouselScrollContainer
             {
                 RelativeSizeAxes = Axes.Both,
             };
@@ -499,13 +499,13 @@ namespace osu.Game.Screens.SelectV2
             // If a keyboard selection is currently made, we want to keep the view stable around the selection.
             // That means that we should offset the immediate scroll position by any change in Y position for the selection.
             if (prevKeyboard.YPosition != null && currentKeyboardSelection.YPosition != prevKeyboard.YPosition)
-                scroll.OffsetScrollPosition((float)(currentKeyboardSelection.YPosition!.Value - prevKeyboard.YPosition.Value));
+                Scroll.OffsetScrollPosition((float)(currentKeyboardSelection.YPosition!.Value - prevKeyboard.YPosition.Value));
         }
 
         private void scrollToSelection()
         {
             if (currentKeyboardSelection.CarouselItem != null)
-                scroll.ScrollTo(currentKeyboardSelection.CarouselItem.CarouselYPosition - visibleHalfHeight);
+                Scroll.ScrollTo(currentKeyboardSelection.CarouselItem.CarouselYPosition - visibleHalfHeight);
         }
 
         #endregion
@@ -519,12 +519,12 @@ namespace osu.Game.Screens.SelectV2
         /// <summary>
         /// The position of the lower visible bound with respect to the current scroll position.
         /// </summary>
-        private float visibleBottomBound => (float)(scroll.Current + DrawHeight + BleedBottom);
+        private float visibleBottomBound => (float)(Scroll.Current + DrawHeight + BleedBottom);
 
         /// <summary>
         /// The position of the upper visible bound with respect to the current scroll position.
         /// </summary>
-        private float visibleUpperBound => (float)(scroll.Current - BleedTop);
+        private float visibleUpperBound => (float)(Scroll.Current - BleedTop);
 
         /// <summary>
         /// Half the height of the visible content.
@@ -557,7 +557,7 @@ namespace osu.Game.Screens.SelectV2
 
             double selectedYPos = currentSelection.CarouselItem?.CarouselYPosition ?? 0;
 
-            foreach (var panel in scroll.Panels)
+            foreach (var panel in Scroll.Panels)
             {
                 var c = (ICarouselPanel)panel;
 
@@ -566,12 +566,12 @@ namespace osu.Game.Screens.SelectV2
                     continue;
 
                 float normalisedDepth = (float)(Math.Abs(selectedYPos - c.DrawYPosition) / DrawHeight);
-                scroll.Panels.ChangeChildDepth(panel, c.Item.DepthLayer + normalisedDepth);
+                Scroll.Panels.ChangeChildDepth(panel, c.Item.DepthLayer + normalisedDepth);
 
                 if (c.DrawYPosition != c.Item.CarouselYPosition)
                     c.DrawYPosition = Interpolation.DampContinuously(c.DrawYPosition, c.Item.CarouselYPosition, 50, Time.Elapsed);
 
-                Vector2 posInScroll = scroll.ToLocalSpace(panel.ScreenSpaceDrawQuad.Centre);
+                Vector2 posInScroll = Scroll.ToLocalSpace(panel.ScreenSpaceDrawQuad.Centre);
                 float dist = Math.Abs(1f - posInScroll.Y / visibleHalfHeight);
 
                 panel.X = offsetX(dist, visibleHalfHeight);
@@ -628,7 +628,7 @@ namespace osu.Game.Screens.SelectV2
             toDisplay.RemoveAll(i => !i.IsVisible);
 
             // Iterate over all panels which are already displayed and figure which need to be displayed / removed.
-            foreach (var panel in scroll.Panels)
+            foreach (var panel in Scroll.Panels)
             {
                 var carouselPanel = (ICarouselPanel)panel;
 
@@ -658,7 +658,7 @@ namespace osu.Game.Screens.SelectV2
                 carouselPanel.DrawYPosition = item.CarouselYPosition;
                 carouselPanel.Item = item;
 
-                scroll.Add(drawable);
+                Scroll.Add(drawable);
             }
 
             // Update the total height of all items (to make the scroll container scrollable through the full height even though
@@ -666,10 +666,10 @@ namespace osu.Game.Screens.SelectV2
             if (carouselItems.Count > 0)
             {
                 var lastItem = carouselItems[^1];
-                scroll.SetLayoutHeight((float)(lastItem.CarouselYPosition + lastItem.DrawHeight + visibleHalfHeight));
+                Scroll.SetLayoutHeight((float)(lastItem.CarouselYPosition + lastItem.DrawHeight + visibleHalfHeight));
             }
             else
-                scroll.SetLayoutHeight(0);
+                Scroll.SetLayoutHeight(0);
         }
 
         private static void expirePanelImmediately(Drawable panel)
@@ -713,7 +713,7 @@ namespace osu.Game.Screens.SelectV2
         /// Implementation of scroll container which handles very large vertical lists by internally using <c>double</c> precision
         /// for pre-display Y values.
         /// </summary>
-        private partial class CarouselScrollContainer : UserTrackingScrollContainer, IKeyBindingHandler<GlobalAction>
+        protected partial class CarouselScrollContainer : UserTrackingScrollContainer, IKeyBindingHandler<GlobalAction>
         {
             public readonly Container Panels;
 

osu.Game/Screens/SelectV2/SongSelect.cs

@@ -99,9 +99,13 @@ namespace osu.Game.Screens.SelectV2
             base.OnEntering(e);
         }
 
+        private const double fade_duration = 300;
+
         public override void OnResuming(ScreenTransitionEvent e)
         {
-            this.FadeIn();
+            this.FadeIn(fade_duration, Easing.OutQuint);
+
+            carousel.VisuallyFocusSelected = false;
 
             // required due to https://github.com/ppy/osu-framework/issues/3218
             modSelectOverlay.SelectedMods.Disabled = false;
@@ -112,16 +116,18 @@ namespace osu.Game.Screens.SelectV2
 
         public override void OnSuspending(ScreenTransitionEvent e)
         {
-            this.Delay(400).FadeOut();
+            this.Delay(100).FadeOut(fade_duration, Easing.OutQuint);
 
             modSelectOverlay.SelectedMods.UnbindFrom(Mods);
 
+            carousel.VisuallyFocusSelected = true;
+
             base.OnSuspending(e);
         }
 
         public override bool OnExiting(ScreenExitEvent e)
         {
-            this.Delay(400).FadeOut();
+            this.FadeOut(fade_duration, Easing.OutQuint);
             return base.OnExiting(e);
         }