From 4290a71f442902dfb21248aa5e214d73b07f99d3 Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Sat, 26 Oct 2019 11:38:05 +0900
Subject: [PATCH] Add special case for timing points

Timing points can't fallback to defaults and must be added at least once.
---
 .../ControlPoints/ControlPointInfo.cs         | 57 +++++++++++--------
 1 file changed, 34 insertions(+), 23 deletions(-)

diff --git a/osu.Game/Beatmaps/ControlPoints/ControlPointInfo.cs b/osu.Game/Beatmaps/ControlPoints/ControlPointInfo.cs
index 24e3c3d8ca..3927f46530 100644
--- a/osu.Game/Beatmaps/ControlPoints/ControlPointInfo.cs
+++ b/osu.Game/Beatmaps/ControlPoints/ControlPointInfo.cs
@@ -85,28 +85,6 @@ public class ControlPointInfo
         /// <returns>The timing control point.</returns>
         public TimingControlPoint TimingPointAt(double time) => binarySearchWithFallback(TimingPoints, time, TimingPoints.Count > 0 ? TimingPoints[0] : null);
 
-        /// <summary>
-        /// Finds the closest <see cref="ControlPoint"/> of the same type as <see cref="referencePoint"/> that is active at <paramref name="time"/>.
-        /// </summary>
-        /// <param name="time">The time to find the timing control point at.</param>
-        /// <param name="referencePoint">A reference point to infer type.</param>
-        /// <returns>The timing control point.</returns>
-        public ControlPoint SimilarPointAt(double time, ControlPoint referencePoint)
-        {
-            switch (referencePoint)
-            {
-                case TimingControlPoint _: return TimingPointAt(time);
-
-                case EffectControlPoint _: return EffectPointAt(time);
-
-                case SampleControlPoint _: return SamplePointAt(time);
-
-                case DifficultyControlPoint _: return DifficultyPointAt(time);
-            }
-
-            return null;
-        }
-
         /// <summary>
         /// Finds the maximum BPM represented by any timing control point.
         /// </summary>
@@ -184,7 +162,7 @@ private T binarySearch<T>(IReadOnlyList<T> list, double time)
 
         public void Add(double time, ControlPoint newPoint, bool force = false)
         {
-            if (!force && SimilarPointAt(time, newPoint)?.EquivalentTo(newPoint) == true)
+            if (!force && checkAlreadyExisting(time, newPoint))
                 return;
 
             GroupAt(time, true).Add(newPoint);
@@ -209,6 +187,39 @@ public ControlPointGroup GroupAt(double time, bool createIfNotExisting = false)
             return null;
         }
 
+        /// <summary>
+        /// Check whether <see cref="newPoint"/> should be added.
+        /// </summary>
+        /// <param name="time">The time to find the timing control point at.</param>
+        /// <param name="newPoint">A point to be added.</param>
+        /// <returns>Whether the new point should be added.</returns>
+        private bool checkAlreadyExisting(double time, ControlPoint newPoint)
+        {
+            ControlPoint existing = null;
+
+            switch (newPoint)
+            {
+                case TimingControlPoint _:
+                    // Timing points are a special case and need to be added regardless of fallback availability.
+                    existing = binarySearch(TimingPoints, time);
+                    break;
+
+                case EffectControlPoint _:
+                    existing = EffectPointAt(time);
+                    break;
+
+                case SampleControlPoint _:
+                    existing = SamplePointAt(time);
+                    break;
+
+                case DifficultyControlPoint _:
+                    existing = DifficultyPointAt(time);
+                    break;
+            }
+
+            return existing?.EquivalentTo(newPoint) == true;
+        }
+
         private void groupItemRemoved(ControlPoint obj)
         {
             switch (obj)