Add looping animation to slider reverse arrows (#7434)

Add looping animation to slider reverse arrows

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableRepeatPoint.cs

@@ -6,13 +6,11 @@ using System.Collections.Generic;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Sprites;
 using osu.Framework.Utils;
 using osu.Game.Rulesets.Objects.Drawables;
 using osu.Game.Rulesets.Osu.Objects.Drawables.Pieces;
 using osu.Game.Rulesets.Scoring;
 using osuTK;
-using osu.Game.Skinning;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables
 {
@@ -23,7 +21,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
         private double animDuration;
 
-        private readonly SkinnableDrawable scaleContainer;
+        private readonly Drawable scaleContainer;
 
         public DrawableRepeatPoint(RepeatPoint repeatPoint, DrawableSlider drawableSlider)
             : base(repeatPoint)
@@ -36,16 +34,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             Blending = BlendingParameters.Additive;
             Origin = Anchor.Centre;
 
-            InternalChild = scaleContainer = new SkinnableDrawable(new OsuSkinComponent(OsuSkinComponents.ReverseArrow), _ => new SpriteIcon
+            InternalChild = scaleContainer = new ReverseArrowPiece();
-            {
-                RelativeSizeAxes = Axes.Both,
-                Icon = FontAwesome.Solid.ChevronRight,
-                Size = new Vector2(0.35f)
-            }, confineMode: ConfineMode.NoScaling)
-            {
-                Anchor = Anchor.Centre,
-                Origin = Anchor.Centre,
-            };
         }
 
         private readonly IBindable<float> scaleBindable = new Bindable<float>();
@@ -65,11 +54,11 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
         protected override void UpdateInitialTransforms()
         {
-            animDuration = Math.Min(150, repeatPoint.SpanDuration / 2);
+            animDuration = Math.Min(300, repeatPoint.SpanDuration);
 
             this.Animate(
                 d => d.FadeIn(animDuration),
-                d => d.ScaleTo(0.5f).ScaleTo(1f, animDuration * 4, Easing.OutElasticHalf)
+                d => d.ScaleTo(0.5f).ScaleTo(1f, animDuration * 2, Easing.OutElasticHalf)
             );
         }
 
@@ -88,7 +77,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                     break;
 
                 case ArmedState.Hit:
-                    this.FadeOut(animDuration, Easing.OutQuint)
+                    this.FadeOut(animDuration, Easing.Out)
                         .ScaleTo(Scale * 1.5f, animDuration, Easing.Out);
                     break;
             }

osu.Game.Rulesets.Osu/Objects/Drawables/Pieces/ReverseArrowPiece.cs

@@ -0,0 +1,43 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Audio.Track;
+using osu.Framework.Graphics;
+using osuTK;
+using osu.Framework.Graphics.Sprites;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Graphics.Containers;
+using osu.Game.Skinning;
+
+namespace osu.Game.Rulesets.Osu.Objects.Drawables.Pieces
+{
+    public class ReverseArrowPiece : BeatSyncedContainer
+    {
+        public ReverseArrowPiece()
+        {
+            Divisor = 2;
+            MinimumBeatLength = 200;
+
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+
+            Blending = BlendingParameters.Additive;
+
+            Size = new Vector2(OsuHitObject.OBJECT_RADIUS * 2);
+
+            Child = new SkinnableDrawable(new OsuSkinComponent(OsuSkinComponents.ReverseArrow), _ => new SpriteIcon
+            {
+                RelativeSizeAxes = Axes.Both,
+                Icon = FontAwesome.Solid.ChevronRight,
+                Size = new Vector2(0.35f)
+            })
+            {
+                Anchor = Anchor.Centre,
+                Origin = Anchor.Centre,
+            };
+        }
+
+        protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, TrackAmplitudes amplitudes) =>
+            Child.ScaleTo(1.3f).ScaleTo(1f, timingPoint.BeatLength, Easing.Out);
+    }
+}

osu.Game/Graphics/Containers/BeatSyncedContainer.cs

@@ -38,6 +38,11 @@ namespace osu.Game.Graphics.Containers
         /// </summary>
         public int Divisor { get; set; } = 1;
 
+        /// <summary>
+        /// An optional minimum beat length. Any beat length below this will be multiplied by two until valid.
+        /// </summary>
+        public double MinimumBeatLength { get; set; }
+
         /// <summary>
         /// Default length of a beat in milliseconds. Used whenever there is no beatmap or track playing.
         /// </summary>
@@ -89,6 +94,9 @@ namespace osu.Game.Graphics.Containers
 
             double beatLength = timingPoint.BeatLength / Divisor;
 
+            while (beatLength < MinimumBeatLength)
+                beatLength *= 2;
+
             int beatIndex = (int)((currentTrackTime - timingPoint.Time) / beatLength) - (effectPoint.OmitFirstBarLine ? 1 : 0);
 
             // The beats before the start of the first control point are off by 1, this should do the trick