From 464be6e64c52b129e36c0e412b00d5f29a4205a1 Mon Sep 17 00:00:00 2001
From: Henry Lin <henry.ys.lin@gmail.com>
Date: Thu, 3 Mar 2022 14:37:39 +0800
Subject: [PATCH] Only call `IUpdatableByPlayfield.Update` if the playfield
 isn't nested

---
 osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs | 11 +++++++++++
 osu.Game/Rulesets/UI/Playfield.cs               |  9 ++++++++-
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs b/osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs
index 9baa252caf..7cf480a11b 100644
--- a/osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs
+++ b/osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs
@@ -5,8 +5,19 @@ using osu.Game.Rulesets.UI;
 
 namespace osu.Game.Rulesets.Mods
 {
+    /// <summary>
+    /// An interface for <see cref="Mod"/>s that are updated every frame by a <see cref="Playfield"/>.
+    /// </summary>
     public interface IUpdatableByPlayfield : IApplicableMod
     {
+        /// <summary>
+        /// Update this <see cref="Mod"/>.
+        /// </summary>
+        /// <param name="playfield">The main <see cref="Playfield"/></param>
+        /// <remarks>
+        /// This method is called once per frame during gameplay by the main <see cref="Playfield"/> only.
+        /// To access nested <see cref="Playfield"/>s, use <see cref="Playfield.NestedPlayfields"/>.
+        /// </remarks>
         void Update(Playfield playfield);
     }
 }
diff --git a/osu.Game/Rulesets/UI/Playfield.cs b/osu.Game/Rulesets/UI/Playfield.cs
index d0bbf859af..30e71dde1c 100644
--- a/osu.Game/Rulesets/UI/Playfield.cs
+++ b/osu.Game/Rulesets/UI/Playfield.cs
@@ -79,6 +79,11 @@ namespace osu.Game.Rulesets.UI
 
         private readonly List<Playfield> nestedPlayfields = new List<Playfield>();
 
+        /// <summary>
+        /// Whether this <see cref="Playfield"/> is nested in another <see cref="Playfield"/>.
+        /// </summary>
+        public bool IsNested { get; private set; }
+
         /// <summary>
         /// Whether judgements should be displayed by this and and all nested <see cref="Playfield"/>s.
         /// </summary>
@@ -206,6 +211,8 @@ namespace osu.Game.Rulesets.UI
         /// <param name="otherPlayfield">The <see cref="Playfield"/> to add.</param>
         protected void AddNested(Playfield otherPlayfield)
         {
+            otherPlayfield.IsNested = true;
+
             otherPlayfield.DisplayJudgements.BindTo(DisplayJudgements);
 
             otherPlayfield.NewResult += (d, r) => NewResult?.Invoke(d, r);
@@ -229,7 +236,7 @@ namespace osu.Game.Rulesets.UI
         {
             base.Update();
 
-            if (mods != null)
+            if (!IsNested && mods != null)
             {
                 foreach (var mod in mods)
                 {