From a8c2b798ad5c71cc2dcdc3d061e54148297218ef Mon Sep 17 00:00:00 2001
From: smoogipoo <smoogipoo@smgi.me>
Date: Thu, 12 Nov 2020 15:24:45 +0900
Subject: [PATCH] Add support for nested hitobject pooling

---
 .../Objects/Drawables/DrawableHitObject.cs     | 18 +++++++++++++++++-
 1 file changed, 17 insertions(+), 1 deletion(-)

diff --git a/osu.Game/Rulesets/Objects/Drawables/DrawableHitObject.cs b/osu.Game/Rulesets/Objects/Drawables/DrawableHitObject.cs
index 244cf831c3..2dba83f2be 100644
--- a/osu.Game/Rulesets/Objects/Drawables/DrawableHitObject.cs
+++ b/osu.Game/Rulesets/Objects/Drawables/DrawableHitObject.cs
@@ -19,6 +19,7 @@ using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Skinning;
 using osu.Game.Configuration;
+using osu.Game.Rulesets.UI;
 using osuTK.Graphics;
 
 namespace osu.Game.Rulesets.Objects.Drawables
@@ -126,6 +127,9 @@ namespace osu.Game.Rulesets.Objects.Drawables
         [CanBeNull]
         private HitObjectLifetimeEntry lifetimeEntry;
 
+        [Resolved(CanBeNull = true)]
+        private DrawableRuleset drawableRuleset { get; set; }
+
         /// <summary>
         /// Creates a new <see cref="DrawableHitObject"/>.
         /// </summary>
@@ -195,7 +199,9 @@ namespace osu.Game.Rulesets.Objects.Drawables
 
             foreach (var h in HitObject.NestedHitObjects)
             {
-                var drawableNested = CreateNestedHitObject(h) ?? throw new InvalidOperationException($"{nameof(CreateNestedHitObject)} returned null for {h.GetType().ReadableName()}.");
+                var drawableNested = drawableRuleset?.GetPooledDrawableRepresentation(h)
+                                     ?? CreateNestedHitObject(h)
+                                     ?? throw new InvalidOperationException($"{nameof(CreateNestedHitObject)} returned null for {h.GetType().ReadableName()}.");
 
                 drawableNested.OnNewResult += onNewResult;
                 drawableNested.OnRevertResult += onRevertResult;
@@ -203,6 +209,8 @@ namespace osu.Game.Rulesets.Objects.Drawables
 
                 nestedHitObjects.Value.Add(drawableNested);
                 AddNestedHitObject(drawableNested);
+
+                drawableNested.OnParentReceived(this);
             }
 
             StartTimeBindable.BindTo(HitObject.StartTimeBindable);
@@ -291,6 +299,14 @@ namespace osu.Game.Rulesets.Objects.Drawables
         {
         }
 
+        /// <summary>
+        /// Invoked when this <see cref="DrawableHitObject"/> receives a new parenting <see cref="DrawableHitObject"/>.
+        /// </summary>
+        /// <param name="parent">The parenting <see cref="DrawableHitObject"/>.</param>
+        protected virtual void OnParentReceived(DrawableHitObject parent)
+        {
+        }
+
         /// <summary>
         /// Invoked by the base <see cref="DrawableHitObject"/> to populate samples, once on initial load and potentially again on any change to the samples collection.
         /// </summary>