Share fade in logic with repeats

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

@@ -14,7 +14,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 {
     public class DrawableSliderTail : DrawableOsuHitObject, IRequireTracking, ITrackSnaking
     {
-        private readonly Slider slider;
+        private readonly SliderTailCircle tailCircle;
 
         /// <summary>
         /// The judgement text is provided by the <see cref="DrawableSlider"/>.
@@ -29,10 +29,10 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
         private readonly Container scaleContainer;
 
-        public DrawableSliderTail(Slider slider, SliderTailCircle hitCircle)
+        public DrawableSliderTail(Slider slider, SliderTailCircle tailCircle)
-            : base(hitCircle)
+            : base(tailCircle)
         {
-            this.slider = slider;
+            this.tailCircle = tailCircle;
             Origin = Anchor.Centre;
 
             Size = new Vector2(OsuHitObject.OBJECT_RADIUS * 2);
@@ -98,9 +98,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                 ApplyResult(r => r.Type = Tracking ? r.Judgement.MaxResult : r.Judgement.MinResult);
         }
 
-        public void UpdateSnakingPosition(Vector2 start, Vector2 end)
+        public void UpdateSnakingPosition(Vector2 start, Vector2 end) =>
-        {
+            Position = tailCircle.RepeatIndex % 2 == 0 ? end : start;
-            Position = end;
-        }
     }
 }

osu.Game.Rulesets.Osu/Objects/Slider.cs

@@ -174,8 +174,10 @@ namespace osu.Game.Rulesets.Osu.Objects
                         // we need to use the LegacyLastTick here for compatibility reasons (difficulty).
                         // it is *okay* to use this because the TailCircle is not used for any meaningful purpose in gameplay.
                         // if this is to change, we should revisit this.
-                        AddNested(TailCircle = new SliderTailCircle(this)
+                        AddNested(TailCircle = new SliderTailCircle
                         {
+                            RepeatIndex = e.SpanIndex,
+                            SpanDuration = SpanDuration,
                             StartTime = e.Time,
                             Position = EndPosition,
                             StackHeight = StackHeight

osu.Game.Rulesets.Osu/Objects/SliderEndCircle.cs

@@ -1,9 +1,34 @@
 // 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 System;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Rulesets.Scoring;
+
 namespace osu.Game.Rulesets.Osu.Objects
 {
-    public class SliderEndCircle : HitCircle
+    /// <summary>
+    /// A hitcircle which is at the end of a slider path (either repeat or final tail).
+    /// </summary>
+    public abstract class SliderEndCircle : HitCircle
     {
+        public int RepeatIndex { get; set; }
+        public double SpanDuration { get; set; }
+
+        protected override void ApplyDefaultsToSelf(ControlPointInfo controlPointInfo, BeatmapDifficulty difficulty)
+        {
+            base.ApplyDefaultsToSelf(controlPointInfo, difficulty);
+
+            // Out preempt should be one span early to give the user ample warning.
+            TimePreempt += SpanDuration;
+
+            // We want to show the first RepeatPoint as the TimePreempt dictates but on short (and possibly fast) sliders
+            // we may need to cut down this time on following RepeatPoints to only show up to two RepeatPoints at any given time.
+            if (RepeatIndex > 0)
+                TimePreempt = Math.Min(SpanDuration * 2, TimePreempt);
+        }
+
+        protected override HitWindows CreateHitWindows() => HitWindows.Empty;
     }
 }

osu.Game.Rulesets.Osu/Objects/SliderRepeat.cs

@@ -1,35 +1,14 @@
 // 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 System;
-using osu.Game.Beatmaps;
-using osu.Game.Beatmaps.ControlPoints;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Osu.Judgements;
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Osu.Objects
 {
-    public class SliderRepeat : OsuHitObject
+    public class SliderRepeat : SliderEndCircle
     {
-        public int RepeatIndex { get; set; }
-        public double SpanDuration { get; set; }
-
-        protected override void ApplyDefaultsToSelf(ControlPointInfo controlPointInfo, BeatmapDifficulty difficulty)
-        {
-            base.ApplyDefaultsToSelf(controlPointInfo, difficulty);
-
-            // Out preempt should be one span early to give the user ample warning.
-            TimePreempt += SpanDuration;
-
-            // We want to show the first RepeatPoint as the TimePreempt dictates but on short (and possibly fast) sliders
-            // we may need to cut down this time on following RepeatPoints to only show up to two RepeatPoints at any given time.
-            if (RepeatIndex > 0)
-                TimePreempt = Math.Min(SpanDuration * 2, TimePreempt);
-        }
-
-        protected override HitWindows CreateHitWindows() => HitWindows.Empty;
-
         public override Judgement CreateJudgement() => new SliderRepeatJudgement();
 
         public class SliderRepeatJudgement : OsuJudgement

osu.Game.Rulesets.Osu/Objects/SliderTailCircle.cs

@@ -1,7 +1,6 @@
 // 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.Bindables;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Osu.Judgements;
@@ -13,18 +12,8 @@ namespace osu.Game.Rulesets.Osu.Objects
     /// Note that this should not be used for timing correctness.
     /// See <see cref="SliderEventType.LegacyLastTick"/> usage in <see cref="Slider"/> for more information.
     /// </summary>
-    public class SliderTailCircle : SliderCircle
+    public class SliderTailCircle : SliderEndCircle
     {
-        private readonly IBindable<int> pathVersion = new Bindable<int>();
-
-        public SliderTailCircle(Slider slider)
-        {
-            pathVersion.BindTo(slider.Path.Version);
-            pathVersion.BindValueChanged(_ => Position = slider.EndPosition);
-        }
-
-        protected override HitWindows CreateHitWindows() => HitWindows.Empty;
-
         public override Judgement CreateJudgement() => new SliderTailJudgement();
 
         public class SliderTailJudgement : OsuJudgement