Merge branch 'master' into taiko-target-classic-position

CodeAnalysis/BannedSymbols.txt

@@ -19,3 +19,7 @@ P:System.Threading.Tasks.Task`1.Result;Don't use Task.Result. Use Task.GetResult
 M:System.Threading.ManualResetEventSlim.Wait();Specify a timeout to avoid waiting forever.
 M:System.String.ToLower();string.ToLower() changes behaviour depending on CultureInfo.CurrentCulture. Use string.ToLowerInvariant() instead. If wanting culture-sensitive behaviour, explicitly provide CultureInfo.CurrentCulture or use LocalisableString.
 M:System.String.ToUpper();string.ToUpper() changes behaviour depending on CultureInfo.CurrentCulture. Use string.ToUpperInvariant() instead. If wanting culture-sensitive behaviour, explicitly provide CultureInfo.CurrentCulture or use LocalisableString.
+M:Humanizer.InflectorExtensions.Pascalize(System.String);Humanizer's .Pascalize() extension method changes behaviour depending on CultureInfo.CurrentCulture. Use StringDehumanizeExtensions.ToPascalCase() instead.
+M:Humanizer.InflectorExtensions.Camelize(System.String);Humanizer's .Camelize() extension method changes behaviour depending on CultureInfo.CurrentCulture. Use StringDehumanizeExtensions.ToCamelCase() instead.
+M:Humanizer.InflectorExtensions.Underscore(System.String);Humanizer's .Underscore() extension method changes behaviour depending on CultureInfo.CurrentCulture. Use StringDehumanizeExtensions.ToSnakeCase() instead.
+M:Humanizer.InflectorExtensions.Kebaberize(System.String);Humanizer's .Kebaberize() extension method changes behaviour depending on CultureInfo.CurrentCulture. Use StringDehumanizeExtensions.ToKebabCase() instead.

osu.Android.props

@@ -52,7 +52,7 @@
   </ItemGroup>
   <ItemGroup>
     <PackageReference Include="ppy.osu.Game.Resources" Version="2022.716.0" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.719.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2022.720.0" />
   </ItemGroup>
   <ItemGroup Label="Transitive Dependencies">
     <!-- Realm needs to be directly referenced in all Xamarin projects, as it will not pull in its transitive dependencies otherwise. -->

osu.Desktop/Program.cs

@@ -37,9 +37,15 @@ namespace osu.Desktop
                 // See https://www.mongodb.com/docs/realm/sdk/dotnet/#supported-platforms
                 if (windowsVersion.Major < 6 || (windowsVersion.Major == 6 && windowsVersion.Minor <= 2))
                 {
+                    // If users running in compatibility mode becomes more of a common thing, we may want to provide better guidance or even consider
+                    // disabling it ourselves.
+                    // We could also better detect compatibility mode if required:
+                    // https://stackoverflow.com/questions/10744651/how-i-can-detect-if-my-application-is-running-under-compatibility-mode#comment58183249_10744730
                     SDL.SDL_ShowSimpleMessageBox(SDL.SDL_MessageBoxFlags.SDL_MESSAGEBOX_ERROR,
                         "Your operating system is too old to run osu!",
-                        "This version of osu! requires at least Windows 8.1 to run.\nPlease upgrade your operating system or consider using an older version of osu!.", IntPtr.Zero);
+                        "This version of osu! requires at least Windows 8.1 to run.\n"
+                        + "Please upgrade your operating system or consider using an older version of osu!.\n\n"
+                        + "If you are running a newer version of windows, please check you don't have \"Compatibility mode\" turned on for osu!", IntPtr.Zero);
                     return;
                 }
 

osu.Game.Benchmarks/BenchmarkHitObject.cs

@@ -0,0 +1,166 @@
+// 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 BenchmarkDotNet.Attributes;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Mania.Objects;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Taiko.Objects;
+
+namespace osu.Game.Benchmarks
+{
+    public class BenchmarkHitObject : BenchmarkTest
+    {
+        [Params(1, 100, 1000)]
+        public int Count { get; set; }
+
+        [Params(false, true)]
+        public bool WithBindableAccess { get; set; }
+
+        [Benchmark]
+        public HitCircle[] OsuCircle()
+        {
+            var circles = new HitCircle[Count];
+
+            for (int i = 0; i < Count; i++)
+            {
+                circles[i] = new HitCircle();
+
+                if (WithBindableAccess)
+                {
+                    _ = circles[i].PositionBindable;
+                    _ = circles[i].ScaleBindable;
+                    _ = circles[i].ComboIndexBindable;
+                    _ = circles[i].ComboOffsetBindable;
+                    _ = circles[i].StackHeightBindable;
+                    _ = circles[i].LastInComboBindable;
+                    _ = circles[i].ComboIndexWithOffsetsBindable;
+                    _ = circles[i].IndexInCurrentComboBindable;
+                    _ = circles[i].SamplesBindable;
+                    _ = circles[i].StartTimeBindable;
+                }
+                else
+                {
+                    _ = circles[i].Position;
+                    _ = circles[i].Scale;
+                    _ = circles[i].ComboIndex;
+                    _ = circles[i].ComboOffset;
+                    _ = circles[i].StackHeight;
+                    _ = circles[i].LastInCombo;
+                    _ = circles[i].ComboIndexWithOffsets;
+                    _ = circles[i].IndexInCurrentCombo;
+                    _ = circles[i].Samples;
+                    _ = circles[i].StartTime;
+                    _ = circles[i].Position;
+                    _ = circles[i].Scale;
+                    _ = circles[i].ComboIndex;
+                    _ = circles[i].ComboOffset;
+                    _ = circles[i].StackHeight;
+                    _ = circles[i].LastInCombo;
+                    _ = circles[i].ComboIndexWithOffsets;
+                    _ = circles[i].IndexInCurrentCombo;
+                    _ = circles[i].Samples;
+                    _ = circles[i].StartTime;
+                }
+            }
+
+            return circles;
+        }
+
+        [Benchmark]
+        public Hit[] TaikoHit()
+        {
+            var hits = new Hit[Count];
+
+            for (int i = 0; i < Count; i++)
+            {
+                hits[i] = new Hit();
+
+                if (WithBindableAccess)
+                {
+                    _ = hits[i].TypeBindable;
+                    _ = hits[i].IsStrongBindable;
+                    _ = hits[i].SamplesBindable;
+                    _ = hits[i].StartTimeBindable;
+                }
+                else
+                {
+                    _ = hits[i].Type;
+                    _ = hits[i].IsStrong;
+                    _ = hits[i].Samples;
+                    _ = hits[i].StartTime;
+                }
+            }
+
+            return hits;
+        }
+
+        [Benchmark]
+        public Fruit[] CatchFruit()
+        {
+            var fruit = new Fruit[Count];
+
+            for (int i = 0; i < Count; i++)
+            {
+                fruit[i] = new Fruit();
+
+                if (WithBindableAccess)
+                {
+                    _ = fruit[i].OriginalXBindable;
+                    _ = fruit[i].XOffsetBindable;
+                    _ = fruit[i].ScaleBindable;
+                    _ = fruit[i].ComboIndexBindable;
+                    _ = fruit[i].HyperDashBindable;
+                    _ = fruit[i].LastInComboBindable;
+                    _ = fruit[i].ComboIndexWithOffsetsBindable;
+                    _ = fruit[i].IndexInCurrentComboBindable;
+                    _ = fruit[i].IndexInBeatmapBindable;
+                    _ = fruit[i].SamplesBindable;
+                    _ = fruit[i].StartTimeBindable;
+                }
+                else
+                {
+                    _ = fruit[i].OriginalX;
+                    _ = fruit[i].XOffset;
+                    _ = fruit[i].Scale;
+                    _ = fruit[i].ComboIndex;
+                    _ = fruit[i].HyperDash;
+                    _ = fruit[i].LastInCombo;
+                    _ = fruit[i].ComboIndexWithOffsets;
+                    _ = fruit[i].IndexInCurrentCombo;
+                    _ = fruit[i].IndexInBeatmap;
+                    _ = fruit[i].Samples;
+                    _ = fruit[i].StartTime;
+                }
+            }
+
+            return fruit;
+        }
+
+        [Benchmark]
+        public Note[] ManiaNote()
+        {
+            var notes = new Note[Count];
+
+            for (int i = 0; i < Count; i++)
+            {
+                notes[i] = new Note();
+
+                if (WithBindableAccess)
+                {
+                    _ = notes[i].ColumnBindable;
+                    _ = notes[i].SamplesBindable;
+                    _ = notes[i].StartTimeBindable;
+                }
+                else
+                {
+                    _ = notes[i].Column;
+                    _ = notes[i].Samples;
+                    _ = notes[i].StartTime;
+                }
+            }
+
+            return notes;
+        }
+    }
+}

osu.Game.Rulesets.Catch/Objects/CatchHitObject.cs

@@ -19,7 +19,9 @@ namespace osu.Game.Rulesets.Catch.Objects
     {
         public const float OBJECT_RADIUS = 64;
 
-        public readonly Bindable<float> OriginalXBindable = new Bindable<float>();
+        private HitObjectProperty<float> originalX;
+
+        public Bindable<float> OriginalXBindable => originalX.Bindable;
 
         /// <summary>
         /// The horizontal position of the hit object between 0 and <see cref="CatchPlayfield.WIDTH"/>.
@@ -31,18 +33,20 @@ namespace osu.Game.Rulesets.Catch.Objects
         [JsonIgnore]
         public float X
         {
-            set => OriginalXBindable.Value = value;
+            set => originalX.Value = value;
         }
 
-        public readonly Bindable<float> XOffsetBindable = new Bindable<float>();
+        private HitObjectProperty<float> xOffset;
+
+        public Bindable<float> XOffsetBindable => xOffset.Bindable;
 
         /// <summary>
         /// A random offset applied to the horizontal position, set by the beatmap processing.
         /// </summary>
         public float XOffset
         {
-            get => XOffsetBindable.Value;
-            set => XOffsetBindable.Value = value;
+            get => xOffset.Value;
+            set => xOffset.Value = value;
         }
 
         /// <summary>
@@ -54,8 +58,8 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// </remarks>
         public float OriginalX
         {
-            get => OriginalXBindable.Value;
-            set => OriginalXBindable.Value = value;
+            get => originalX.Value;
+            set => originalX.Value = value;
         }
 
         /// <summary>
@@ -69,59 +73,71 @@ namespace osu.Game.Rulesets.Catch.Objects
 
         public double TimePreempt { get; set; } = 1000;
 
-        public readonly Bindable<int> IndexInBeatmapBindable = new Bindable<int>();
+        private HitObjectProperty<int> indexInBeatmap;
+
+        public Bindable<int> IndexInBeatmapBindable => indexInBeatmap.Bindable;
 
         public int IndexInBeatmap
         {
-            get => IndexInBeatmapBindable.Value;
-            set => IndexInBeatmapBindable.Value = value;
+            get => indexInBeatmap.Value;
+            set => indexInBeatmap.Value = value;
         }
 
         public virtual bool NewCombo { get; set; }
 
         public int ComboOffset { get; set; }
 
-        public Bindable<int> IndexInCurrentComboBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> indexInCurrentCombo;
+
+        public Bindable<int> IndexInCurrentComboBindable => indexInCurrentCombo.Bindable;
 
         public int IndexInCurrentCombo
         {
-            get => IndexInCurrentComboBindable.Value;
-            set => IndexInCurrentComboBindable.Value = value;
+            get => indexInCurrentCombo.Value;
+            set => indexInCurrentCombo.Value = value;
         }
 
-        public Bindable<int> ComboIndexBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> comboIndex;
+
+        public Bindable<int> ComboIndexBindable => comboIndex.Bindable;
 
         public int ComboIndex
         {
-            get => ComboIndexBindable.Value;
-            set => ComboIndexBindable.Value = value;
+            get => comboIndex.Value;
+            set => comboIndex.Value = value;
         }
 
-        public Bindable<int> ComboIndexWithOffsetsBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> comboIndexWithOffsets;
+
+        public Bindable<int> ComboIndexWithOffsetsBindable => comboIndexWithOffsets.Bindable;
 
         public int ComboIndexWithOffsets
         {
-            get => ComboIndexWithOffsetsBindable.Value;
-            set => ComboIndexWithOffsetsBindable.Value = value;
+            get => comboIndexWithOffsets.Value;
+            set => comboIndexWithOffsets.Value = value;
         }
 
-        public Bindable<bool> LastInComboBindable { get; } = new Bindable<bool>();
+        private HitObjectProperty<bool> lastInCombo;
+
+        public Bindable<bool> LastInComboBindable => lastInCombo.Bindable;
 
         /// <summary>
         /// The next fruit starts a new combo. Used for explodey.
         /// </summary>
         public virtual bool LastInCombo
         {
-            get => LastInComboBindable.Value;
-            set => LastInComboBindable.Value = value;
+            get => lastInCombo.Value;
+            set => lastInCombo.Value = value;
         }
 
-        public readonly Bindable<float> ScaleBindable = new Bindable<float>(1);
+        private HitObjectProperty<float> scale = new HitObjectProperty<float>(1);
+
+        public Bindable<float> ScaleBindable => scale.Bindable;
 
         public float Scale
         {
-            get => ScaleBindable.Value;
-            set => ScaleBindable.Value = value;
+            get => scale.Value;
+            set => scale.Value = value;
         }
 
         /// <summary>

osu.Game.Rulesets.Catch/Objects/PalpableCatchHitObject.cs

@@ -5,6 +5,7 @@
 
 using Newtonsoft.Json;
 using osu.Framework.Bindables;
+using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Skinning;
 using osuTK.Graphics;
@@ -24,12 +25,14 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// </summary>
         public float DistanceToHyperDash { get; set; }
 
-        public readonly Bindable<bool> HyperDashBindable = new Bindable<bool>();
+        private HitObjectProperty<bool> hyperDash;
+
+        public Bindable<bool> HyperDashBindable => hyperDash.Bindable;
 
         /// <summary>
         /// Whether this fruit can initiate a hyperdash.
         /// </summary>
-        public bool HyperDash => HyperDashBindable.Value;
+        public bool HyperDash => hyperDash.Value;
 
         private CatchHitObject hyperDashTarget;
 

osu.Game.Rulesets.Mania/Objects/ManiaHitObject.cs

@@ -13,12 +13,14 @@ namespace osu.Game.Rulesets.Mania.Objects
 {
     public abstract class ManiaHitObject : HitObject, IHasColumn, IHasXPosition
     {
-        public readonly Bindable<int> ColumnBindable = new Bindable<int>();
+        private HitObjectProperty<int> column;
+
+        public Bindable<int> ColumnBindable => column.Bindable;
 
         public virtual int Column
         {
-            get => ColumnBindable.Value;
-            set => ColumnBindable.Value = value;
+            get => column.Value;
+            set => column.Value = value;
         }
 
         protected override HitWindows CreateHitWindows() => new ManiaHitWindows();

osu.Game.Rulesets.Osu.Tests/OsuDifficultyCalculatorTest.cs

@@ -17,18 +17,18 @@ namespace osu.Game.Rulesets.Osu.Tests
     {
         protected override string ResourceAssembly => "osu.Game.Rulesets.Osu";
 
-        [TestCase(6.6972307565739273d, 206, "diffcalc-test")]
-        [TestCase(1.4484754139145539d, 45, "zero-length-sliders")]
+        [TestCase(6.6369583000323935d, 206, "diffcalc-test")]
+        [TestCase(1.4476531024675374d, 45, "zero-length-sliders")]
         public void Test(double expectedStarRating, int expectedMaxCombo, string name)
             => base.Test(expectedStarRating, expectedMaxCombo, name);
 
-        [TestCase(8.9382559208689809d, 206, "diffcalc-test")]
-        [TestCase(1.7548875851757628d, 45, "zero-length-sliders")]
+        [TestCase(8.8816128335486386d, 206, "diffcalc-test")]
+        [TestCase(1.7540389962596916d, 45, "zero-length-sliders")]
         public void TestClockRateAdjusted(double expectedStarRating, int expectedMaxCombo, string name)
             => Test(expectedStarRating, expectedMaxCombo, name, new OsuModDoubleTime());
 
-        [TestCase(6.6972307218715166d, 239, "diffcalc-test")]
-        [TestCase(1.4484754139145537d, 54, "zero-length-sliders")]
+        [TestCase(6.6369583000323935d, 239, "diffcalc-test")]
+        [TestCase(1.4476531024675374d, 54, "zero-length-sliders")]
         public void TestClassicMod(double expectedStarRating, int expectedMaxCombo, string name)
             => Test(expectedStarRating, expectedMaxCombo, name, new OsuModClassic());
 

osu.Game.Rulesets.Osu/Difficulty/Evaluators/AimEvaluator.cs

@@ -108,13 +108,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty.Evaluators
                 // Reward for % distance up to 125 / strainTime for overlaps where velocity is still changing.
                 double overlapVelocityBuff = Math.Min(125 / Math.Min(osuCurrObj.StrainTime, osuLastObj.StrainTime), Math.Abs(prevVelocity - currVelocity));
 
-                // Reward for % distance slowed down compared to previous, paying attention to not award overlap
-                double nonOverlapVelocityBuff = Math.Abs(prevVelocity - currVelocity)
-                                                // do not award overlap
-                                                * Math.Pow(Math.Sin(Math.PI / 2 * Math.Min(1, Math.Min(osuCurrObj.LazyJumpDistance, osuLastObj.LazyJumpDistance) / 100)), 2);
-
-                // Choose the largest bonus, multiplied by ratio.
-                velocityChangeBonus = Math.Max(overlapVelocityBuff, nonOverlapVelocityBuff) * distRatio;
+                velocityChangeBonus = overlapVelocityBuff * distRatio;
 
                 // Penalize for rhythm changes.
                 velocityChangeBonus *= Math.Pow(Math.Min(osuCurrObj.StrainTime, osuLastObj.StrainTime) / Math.Max(osuCurrObj.StrainTime, osuLastObj.StrainTime), 2);

osu.Game.Rulesets.Osu/Edit/Blueprints/Sliders/SliderPlacementBlueprint.cs

@@ -16,6 +16,7 @@ using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Osu.Edit.Blueprints.HitCircles.Components;
 using osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders.Components;
+using osu.Game.Rulesets.Osu.Objects;
 using osu.Game.Screens.Edit;
 using osuTK;
 using osuTK.Input;
@@ -24,7 +25,7 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders
 {
     public class SliderPlacementBlueprint : PlacementBlueprint
     {
-        public new Objects.Slider HitObject => (Objects.Slider)base.HitObject;
+        public new Slider HitObject => (Slider)base.HitObject;
 
         private SliderBodyPiece bodyPiece;
         private HitCirclePiece headCirclePiece;
@@ -42,7 +43,7 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders
         private IDistanceSnapProvider snapProvider { get; set; }
 
         public SliderPlacementBlueprint()
-            : base(new Objects.Slider())
+            : base(new Slider())
         {
             RelativeSizeAxes = Axes.Both;
 
@@ -82,7 +83,9 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders
                 case SliderPlacementState.Initial:
                     BeginPlacement();
 
-                    var nearestDifficultyPoint = editorBeatmap.HitObjects.LastOrDefault(h => h.GetEndTime() < HitObject.StartTime)?.DifficultyControlPoint?.DeepClone() as DifficultyControlPoint;
+                    var nearestDifficultyPoint = editorBeatmap.HitObjects
+                                                              .LastOrDefault(h => h is Slider && h.GetEndTime() < HitObject.StartTime)?
+                                                              .DifficultyControlPoint?.DeepClone() as DifficultyControlPoint;
 
                     HitObject.DifficultyControlPoint = nearestDifficultyPoint ?? new DifficultyControlPoint();
                     HitObject.Position = ToLocalSpace(result.ScreenSpacePosition);

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

@@ -7,12 +7,12 @@ using System;
 using System.Linq;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
-using osu.Game.Rulesets.Objects;
-using osuTK;
-using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Osu.Scoring;
 using osu.Game.Rulesets.Scoring;
+using osuTK;
 
 namespace osu.Game.Rulesets.Osu.Objects
 {
@@ -36,12 +36,14 @@ namespace osu.Game.Rulesets.Osu.Objects
         public double TimePreempt = 600;
         public double TimeFadeIn = 400;
 
-        public readonly Bindable<Vector2> PositionBindable = new Bindable<Vector2>();
+        private HitObjectProperty<Vector2> position;
+
+        public Bindable<Vector2> PositionBindable => position.Bindable;
 
         public virtual Vector2 Position
         {
-            get => PositionBindable.Value;
-            set => PositionBindable.Value = value;
+            get => position.Value;
+            set => position.Value = value;
         }
 
         public float X => Position.X;
@@ -53,66 +55,80 @@ namespace osu.Game.Rulesets.Osu.Objects
 
         public Vector2 StackedEndPosition => EndPosition + StackOffset;
 
-        public readonly Bindable<int> StackHeightBindable = new Bindable<int>();
+        private HitObjectProperty<int> stackHeight;
+
+        public Bindable<int> StackHeightBindable => stackHeight.Bindable;
 
         public int StackHeight
         {
-            get => StackHeightBindable.Value;
-            set => StackHeightBindable.Value = value;
+            get => stackHeight.Value;
+            set => stackHeight.Value = value;
         }
 
         public virtual Vector2 StackOffset => new Vector2(StackHeight * Scale * -6.4f);
 
         public double Radius => OBJECT_RADIUS * Scale;
 
-        public readonly Bindable<float> ScaleBindable = new BindableFloat(1);
+        private HitObjectProperty<float> scale = new HitObjectProperty<float>(1);
+
+        public Bindable<float> ScaleBindable => scale.Bindable;
 
         public float Scale
         {
-            get => ScaleBindable.Value;
-            set => ScaleBindable.Value = value;
+            get => scale.Value;
+            set => scale.Value = value;
         }
 
         public virtual bool NewCombo { get; set; }
 
-        public readonly Bindable<int> ComboOffsetBindable = new Bindable<int>();
+        private HitObjectProperty<int> comboOffset;
+
+        public Bindable<int> ComboOffsetBindable => comboOffset.Bindable;
 
         public int ComboOffset
         {
-            get => ComboOffsetBindable.Value;
-            set => ComboOffsetBindable.Value = value;
+            get => comboOffset.Value;
+            set => comboOffset.Value = value;
         }
 
-        public Bindable<int> IndexInCurrentComboBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> indexInCurrentCombo;
+
+        public Bindable<int> IndexInCurrentComboBindable => indexInCurrentCombo.Bindable;
 
         public virtual int IndexInCurrentCombo
         {
-            get => IndexInCurrentComboBindable.Value;
-            set => IndexInCurrentComboBindable.Value = value;
+            get => indexInCurrentCombo.Value;
+            set => indexInCurrentCombo.Value = value;
         }
 
-        public Bindable<int> ComboIndexBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> comboIndex;
+
+        public Bindable<int> ComboIndexBindable => comboIndex.Bindable;
 
         public virtual int ComboIndex
         {
-            get => ComboIndexBindable.Value;
-            set => ComboIndexBindable.Value = value;
+            get => comboIndex.Value;
+            set => comboIndex.Value = value;
         }
 
-        public Bindable<int> ComboIndexWithOffsetsBindable { get; } = new Bindable<int>();
+        private HitObjectProperty<int> comboIndexWithOffsets;
+
+        public Bindable<int> ComboIndexWithOffsetsBindable => comboIndexWithOffsets.Bindable;
 
         public int ComboIndexWithOffsets
         {
-            get => ComboIndexWithOffsetsBindable.Value;
-            set => ComboIndexWithOffsetsBindable.Value = value;
+            get => comboIndexWithOffsets.Value;
+            set => comboIndexWithOffsets.Value = value;
         }
 
-        public Bindable<bool> LastInComboBindable { get; } = new Bindable<bool>();
+        private HitObjectProperty<bool> lastInCombo;
+
+        public Bindable<bool> LastInComboBindable => lastInCombo.Bindable;
 
         public bool LastInCombo
         {
-            get => LastInComboBindable.Value;
-            set => LastInComboBindable.Value = value;
+            get => lastInCombo.Value;
+            set => lastInCombo.Value = value;
         }
 
         protected OsuHitObject()

osu.Game.Rulesets.Osu/Skinning/Default/DefaultFollowCircle.cs

@@ -1,10 +1,12 @@
 // 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.Diagnostics;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
+using osu.Framework.Utils;
 using osu.Game.Rulesets.Osu.Objects.Drawables;
 using osuTK.Graphics;
 
@@ -32,19 +34,35 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
 
         protected override void OnTrackingChanged(ValueChangedEvent<bool> tracking)
         {
-            const float scale_duration = 300f;
-            const float fade_duration = 300f;
+            Debug.Assert(ParentObject != null);
 
-            this.ScaleTo(tracking.NewValue ? DrawableSliderBall.FOLLOW_AREA : 1f, scale_duration, Easing.OutQuint)
-                .FadeTo(tracking.NewValue ? 1f : 0, fade_duration, Easing.OutQuint);
+            const float duration = 300f;
+
+            if (ParentObject.Judged)
+                return;
+
+            if (tracking.NewValue)
+            {
+                if (Precision.AlmostEquals(0, Alpha))
+                    this.ScaleTo(1);
+
+                this.ScaleTo(DrawableSliderBall.FOLLOW_AREA, duration, Easing.OutQuint)
+                    .FadeTo(1f, duration, Easing.OutQuint);
+            }
+            else
+            {
+                this.ScaleTo(DrawableSliderBall.FOLLOW_AREA * 1.2f, duration / 2, Easing.OutQuint)
+                    .FadeTo(0, duration / 2, Easing.OutQuint);
+            }
         }
 
         protected override void OnSliderEnd()
         {
-            const float fade_duration = 450f;
+            const float fade_duration = 300;
 
             // intentionally pile on an extra FadeOut to make it happen much faster
-            this.FadeOut(fade_duration / 4, Easing.Out);
+            this.ScaleTo(1, fade_duration, Easing.OutQuint);
+            this.FadeOut(fade_duration / 2, Easing.OutQuint);
         }
     }
 }

osu.Game.Rulesets.Taiko/Difficulty/TaikoPerformanceCalculator.cs

@@ -35,13 +35,13 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
             countMeh = score.Statistics.GetValueOrDefault(HitResult.Meh);
             countMiss = score.Statistics.GetValueOrDefault(HitResult.Miss);
 
-            double multiplier = 1.1; // This is being adjusted to keep the final pp value scaled around what it used to be when changing things
-
-            if (score.Mods.Any(m => m is ModNoFail))
-                multiplier *= 0.90;
+            double multiplier = 1.12; // This is being adjusted to keep the final pp value scaled around what it used to be when changing things
 
             if (score.Mods.Any(m => m is ModHidden))
-                multiplier *= 1.10;
+                multiplier *= 1.075;
+
+            if (score.Mods.Any(m => m is ModEasy))
+                multiplier *= 0.975;
 
             double difficultyValue = computeDifficultyValue(score, taikoAttributes);
             double accuracyValue = computeAccuracyValue(score, taikoAttributes);
@@ -61,12 +61,15 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
 
         private double computeDifficultyValue(ScoreInfo score, TaikoDifficultyAttributes attributes)
         {
-            double difficultyValue = Math.Pow(5 * Math.Max(1.0, attributes.StarRating / 0.175) - 4.0, 2.25) / 450.0;
+            double difficultyValue = Math.Pow(5 * Math.Max(1.0, attributes.StarRating / 0.115) - 4.0, 2.25) / 1150.0;
 
             double lengthBonus = 1 + 0.1 * Math.Min(1.0, totalHits / 1500.0);
             difficultyValue *= lengthBonus;
 
-            difficultyValue *= Math.Pow(0.985, countMiss);
+            difficultyValue *= Math.Pow(0.986, countMiss);
+
+            if (score.Mods.Any(m => m is ModEasy))
+                difficultyValue *= 0.980;
 
             if (score.Mods.Any(m => m is ModHidden))
                 difficultyValue *= 1.025;
@@ -74,7 +77,7 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
             if (score.Mods.Any(m => m is ModFlashlight<TaikoHitObject>))
                 difficultyValue *= 1.05 * lengthBonus;
 
-            return difficultyValue * score.Accuracy;
+            return difficultyValue * Math.Pow(score.Accuracy, 1.5);
         }
 
         private double computeAccuracyValue(ScoreInfo score, TaikoDifficultyAttributes attributes)
@@ -82,10 +85,16 @@ namespace osu.Game.Rulesets.Taiko.Difficulty
             if (attributes.GreatHitWindow <= 0)
                 return 0;
 
-            double accValue = Math.Pow(150.0 / attributes.GreatHitWindow, 1.1) * Math.Pow(score.Accuracy, 15) * 22.0;
+            double accuracyValue = Math.Pow(140.0 / attributes.GreatHitWindow, 1.1) * Math.Pow(score.Accuracy, 12.0) * 27;
 
-            // Bonus for many objects - it's harder to keep good accuracy up for longer
-            return accValue * Math.Min(1.15, Math.Pow(totalHits / 1500.0, 0.3));
+            double lengthBonus = Math.Min(1.15, Math.Pow(totalHits / 1500.0, 0.3));
+            accuracyValue *= lengthBonus;
+
+            // Slight HDFL Bonus for accuracy.
+            if (score.Mods.Any(m => m is ModFlashlight<TaikoHitObject>) && score.Mods.Any(m => m is ModHidden))
+                accuracyValue *= 1.10 * lengthBonus;
+
+            return accuracyValue;
         }
 
         private int totalHits => countGreat + countOk + countMeh + countMiss;

osu.Game.Rulesets.Taiko/Objects/BarLine.cs

@@ -11,14 +11,16 @@ namespace osu.Game.Rulesets.Taiko.Objects
 {
     public class BarLine : TaikoHitObject, IBarLine
     {
+        private HitObjectProperty<bool> major;
+
+        public Bindable<bool> MajorBindable => major.Bindable;
+
         public bool Major
         {
-            get => MajorBindable.Value;
-            set => MajorBindable.Value = value;
+            get => major.Value;
+            set => major.Value = value;
         }
 
-        public readonly Bindable<bool> MajorBindable = new BindableBool();
-
         public override Judgement CreateJudgement() => new IgnoreJudgement();
     }
 }

osu.Game.Rulesets.Taiko/Objects/Hit.cs

@@ -7,6 +7,7 @@ using System.Linq;
 using osu.Framework.Bindables;
 using osu.Framework.Extensions.Color4Extensions;
 using osu.Game.Audio;
+using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
 using osuTK.Graphics;
 
@@ -14,19 +15,21 @@ namespace osu.Game.Rulesets.Taiko.Objects
 {
     public class Hit : TaikoStrongableHitObject, IHasDisplayColour
     {
-        public readonly Bindable<HitType> TypeBindable = new Bindable<HitType>();
+        private HitObjectProperty<HitType> type;
 
-        public Bindable<Color4> DisplayColour { get; } = new Bindable<Color4>(COLOUR_CENTRE);
+        public Bindable<HitType> TypeBindable => type.Bindable;
 
         /// <summary>
         /// The <see cref="HitType"/> that actuates this <see cref="Hit"/>.
         /// </summary>
         public HitType Type
         {
-            get => TypeBindable.Value;
-            set => TypeBindable.Value = value;
+            get => type.Value;
+            set => type.Value = value;
         }
 
+        public Bindable<Color4> DisplayColour { get; } = new Bindable<Color4>(COLOUR_CENTRE);
+
         public static readonly Color4 COLOUR_CENTRE = Color4Extensions.FromHex(@"bb1177");
         public static readonly Color4 COLOUR_RIM = Color4Extensions.FromHex(@"2299bb");
 

osu.Game.Tests/Extensions/StringDehumanizeExtensionsTest.cs

@@ -0,0 +1,85 @@
+// 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 System.Globalization;
+using NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Game.Extensions;
+
+namespace osu.Game.Tests.Extensions
+{
+    [TestFixture]
+    public class StringDehumanizeExtensionsTest
+    {
+        [Test]
+        [TestCase("single", "Single")]
+        [TestCase("example word", "ExampleWord")]
+        [TestCase("mixed Casing test", "MixedCasingTest")]
+        [TestCase("PascalCase", "PascalCase")]
+        [TestCase("camelCase", "CamelCase")]
+        [TestCase("snake_case", "SnakeCase")]
+        [TestCase("kebab-case", "KebabCase")]
+        [TestCase("i will not break in a different culture", "IWillNotBreakInADifferentCulture", "tr-TR")]
+        public void TestToPascalCase(string input, string expectedOutput, string? culture = null)
+        {
+            using (temporaryCurrentCulture(culture))
+                Assert.That(input.ToPascalCase(), Is.EqualTo(expectedOutput));
+        }
+
+        [Test]
+        [TestCase("single", "single")]
+        [TestCase("example word", "exampleWord")]
+        [TestCase("mixed Casing test", "mixedCasingTest")]
+        [TestCase("PascalCase", "pascalCase")]
+        [TestCase("camelCase", "camelCase")]
+        [TestCase("snake_case", "snakeCase")]
+        [TestCase("kebab-case", "kebabCase")]
+        [TestCase("I will not break in a different culture", "iWillNotBreakInADifferentCulture", "tr-TR")]
+        public void TestToCamelCase(string input, string expectedOutput, string? culture = null)
+        {
+            using (temporaryCurrentCulture(culture))
+                Assert.That(input.ToCamelCase(), Is.EqualTo(expectedOutput));
+        }
+
+        [Test]
+        [TestCase("single", "single")]
+        [TestCase("example word", "example_word")]
+        [TestCase("mixed Casing test", "mixed_casing_test")]
+        [TestCase("PascalCase", "pascal_case")]
+        [TestCase("camelCase", "camel_case")]
+        [TestCase("snake_case", "snake_case")]
+        [TestCase("kebab-case", "kebab_case")]
+        [TestCase("I will not break in a different culture", "i_will_not_break_in_a_different_culture", "tr-TR")]
+        public void TestToSnakeCase(string input, string expectedOutput, string? culture = null)
+        {
+            using (temporaryCurrentCulture(culture))
+                Assert.That(input.ToSnakeCase(), Is.EqualTo(expectedOutput));
+        }
+
+        [Test]
+        [TestCase("single", "single")]
+        [TestCase("example word", "example-word")]
+        [TestCase("mixed Casing test", "mixed-casing-test")]
+        [TestCase("PascalCase", "pascal-case")]
+        [TestCase("camelCase", "camel-case")]
+        [TestCase("snake_case", "snake-case")]
+        [TestCase("kebab-case", "kebab-case")]
+        [TestCase("I will not break in a different culture", "i-will-not-break-in-a-different-culture", "tr-TR")]
+        public void TestToKebabCase(string input, string expectedOutput, string? culture = null)
+        {
+            using (temporaryCurrentCulture(culture))
+                Assert.That(input.ToKebabCase(), Is.EqualTo(expectedOutput));
+        }
+
+        private IDisposable temporaryCurrentCulture(string? cultureName)
+        {
+            var storedCulture = CultureInfo.CurrentCulture;
+
+            if (cultureName != null)
+                CultureInfo.CurrentCulture = new CultureInfo(cultureName);
+
+            return new InvokeOnDisposal(() => CultureInfo.CurrentCulture = storedCulture);
+        }
+    }
+}

osu.Game.Tests/Mods/ModDifficultyAdjustTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using NUnit.Framework;
 using osu.Game.Beatmaps;
@@ -17,7 +15,7 @@ namespace osu.Game.Tests.Mods
     [TestFixture]
     public class ModDifficultyAdjustTest
     {
-        private TestModDifficultyAdjust testMod;
+        private TestModDifficultyAdjust testMod = null!;
 
         [SetUp]
         public void Setup()
@@ -148,7 +146,7 @@ namespace osu.Game.Tests.Mods
                     yield return new TestModDifficultyAdjust();
             }
 
-            public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod> mods = null)
+            public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod>? mods = null)
             {
                 throw new System.NotImplementedException();
             }

osu.Game.Tests/Mods/ModSettingsEqualityComparison.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using NUnit.Framework;
 using osu.Game.Online.API;
 using osu.Game.Rulesets.Osu;

osu.Game.Tests/Mods/ModSettingsTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using NUnit.Framework;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Mods;

osu.Game.Tests/Mods/ModUtilsTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Linq;
 using Moq;
@@ -164,19 +162,19 @@ namespace osu.Game.Tests.Mods
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new InvalidMultiplayerMod() },
-                null
+                Array.Empty<Type>()
             },
             // invalid free mod is valid for local.
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new InvalidMultiplayerFreeMod() },
-                null
+                Array.Empty<Type>()
             },
             // valid pair.
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new OsuModHardRock() },
-                null
+                Array.Empty<Type>()
             },
         };
 
@@ -216,13 +214,13 @@ namespace osu.Game.Tests.Mods
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new InvalidMultiplayerFreeMod() },
-                null
+                Array.Empty<Type>()
             },
             // valid pair.
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new OsuModHardRock() },
-                null
+                Array.Empty<Type>()
             },
         };
 
@@ -256,19 +254,19 @@ namespace osu.Game.Tests.Mods
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new OsuModApproachDifferent() },
-                null,
+                Array.Empty<Type>(),
             },
             // incompatible pair with derived class is valid for free mods.
             new object[]
             {
                 new Mod[] { new OsuModDeflate(), new OsuModSpinIn() },
-                null,
+                Array.Empty<Type>(),
             },
             // valid pair.
             new object[]
             {
                 new Mod[] { new OsuModHidden(), new OsuModHardRock() },
-                null
+                Array.Empty<Type>()
             },
         };
 
@@ -277,12 +275,12 @@ namespace osu.Game.Tests.Mods
         {
             bool isValid = ModUtils.CheckValidForGameplay(inputMods, out var invalid);
 
-            Assert.That(isValid, Is.EqualTo(expectedInvalid == null));
+            Assert.That(isValid, Is.EqualTo(expectedInvalid.Length == 0));
 
             if (isValid)
                 Assert.IsNull(invalid);
             else
-                Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
+                Assert.That(invalid?.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
         }
 
         [TestCaseSource(nameof(invalid_multiplayer_mod_test_scenarios))]
@@ -290,12 +288,12 @@ namespace osu.Game.Tests.Mods
         {
             bool isValid = ModUtils.CheckValidRequiredModsForMultiplayer(inputMods, out var invalid);
 
-            Assert.That(isValid, Is.EqualTo(expectedInvalid == null));
+            Assert.That(isValid, Is.EqualTo(expectedInvalid.Length == 0));
 
             if (isValid)
                 Assert.IsNull(invalid);
             else
-                Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
+                Assert.That(invalid?.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
         }
 
         [TestCaseSource(nameof(invalid_free_mod_test_scenarios))]
@@ -303,12 +301,12 @@ namespace osu.Game.Tests.Mods
         {
             bool isValid = ModUtils.CheckValidFreeModsForMultiplayer(inputMods, out var invalid);
 
-            Assert.That(isValid, Is.EqualTo(expectedInvalid == null));
+            Assert.That(isValid, Is.EqualTo(expectedInvalid.Length == 0));
 
             if (isValid)
                 Assert.IsNull(invalid);
             else
-                Assert.That(invalid.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
+                Assert.That(invalid?.Select(t => t.GetType()), Is.EquivalentTo(expectedInvalid));
         }
 
         public abstract class CustomMod1 : Mod, IModCompatibilitySpecification

osu.Game.Tests/Mods/MultiModIncompatibilityTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -29,10 +27,10 @@ namespace osu.Game.Tests.Mods
         [TestCase(typeof(ManiaRuleset))]
         public void TestAllMultiModsFromRulesetAreIncompatible(Type rulesetType)
         {
-            var ruleset = (Ruleset)Activator.CreateInstance(rulesetType);
+            var ruleset = Activator.CreateInstance(rulesetType) as Ruleset;
             Assert.That(ruleset, Is.Not.Null);
 
-            var allMultiMods = getMultiMods(ruleset);
+            var allMultiMods = getMultiMods(ruleset!);
 
             Assert.Multiple(() =>
             {

osu.Game.Tests/Mods/SettingsSourceAttributeTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Bindables;

osu.Game.Tests/Mods/TestCustomisableModRuleset.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using osu.Framework.Bindables;
@@ -33,7 +31,7 @@ namespace osu.Game.Tests.Mods
             return Array.Empty<Mod>();
         }
 
-        public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod> mods = null) => throw new NotImplementedException();
+        public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod>? mods = null) => throw new NotImplementedException();
 
         public override IBeatmapConverter CreateBeatmapConverter(IBeatmap beatmap) => throw new NotImplementedException();
 

osu.Game.Tests/Online/TestSceneBeatmapDownloading.cs

@@ -80,7 +80,7 @@ namespace osu.Game.Tests.Online
         {
             AddStep("download beatmap", () => beatmaps.Download(test_db_model));
 
-            AddStep("cancel download from request", () => beatmaps.GetExistingDownload(test_db_model).Cancel());
+            AddStep("cancel download from request", () => beatmaps.GetExistingDownload(test_db_model)!.Cancel());
 
             AddUntilStep("is removed from download list", () => beatmaps.GetExistingDownload(test_db_model) == null);
             AddAssert("is notification cancelled", () => recentNotification.State == ProgressNotificationState.Cancelled);

osu.Game.Tests/Online/TestSceneOnlinePlayBeatmapAvailabilityTracker.cs

@@ -126,10 +126,10 @@ namespace osu.Game.Tests.Online
             AddStep("start downloading", () => beatmapDownloader.Download(testBeatmapSet));
             addAvailabilityCheckStep("state downloading 0%", () => BeatmapAvailability.Downloading(0.0f));
 
-            AddStep("set progress 40%", () => ((TestDownloadRequest)beatmapDownloader.GetExistingDownload(testBeatmapSet)).SetProgress(0.4f));
+            AddStep("set progress 40%", () => ((TestDownloadRequest)beatmapDownloader.GetExistingDownload(testBeatmapSet))!.SetProgress(0.4f));
             addAvailabilityCheckStep("state downloading 40%", () => BeatmapAvailability.Downloading(0.4f));
 
-            AddStep("finish download", () => ((TestDownloadRequest)beatmapDownloader.GetExistingDownload(testBeatmapSet)).TriggerSuccess(testBeatmapFile));
+            AddStep("finish download", () => ((TestDownloadRequest)beatmapDownloader.GetExistingDownload(testBeatmapSet))!.TriggerSuccess(testBeatmapFile));
             addAvailabilityCheckStep("state importing", BeatmapAvailability.Importing);
 
             AddStep("allow importing", () => beatmaps.AllowImport.SetResult(true));
@@ -246,7 +246,7 @@ namespace osu.Game.Tests.Online
                 => new TestDownloadRequest(set);
         }
 
-        private class TestDownloadRequest : ArchiveDownloadRequest<IBeatmapSetInfo>
+        internal class TestDownloadRequest : ArchiveDownloadRequest<IBeatmapSetInfo>
         {
             public new void SetProgress(float progress) => base.SetProgress(progress);
             public new void TriggerSuccess(string filename) => base.TriggerSuccess(filename);

osu.Game.Tests/Rulesets/Mods/ModTimeRampTest.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using NUnit.Framework;
 using osu.Framework.Audio.Track;
 using osu.Framework.Timing;
@@ -19,8 +17,8 @@ namespace osu.Game.Tests.Rulesets.Mods
         private const double start_time = 1000;
         private const double duration = 9000;
 
-        private TrackVirtual track;
-        private OsuPlayfield playfield;
+        private TrackVirtual track = null!;
+        private OsuPlayfield playfield = null!;
 
         [SetUp]
         public void SetUp()

osu.Game.Tests/Visual/Multiplayer/TestSceneMultiplayer.cs

@@ -402,16 +402,18 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestPlayStartsWithCorrectBeatmapWhileAtSongSelect()
         {
-            createRoom(() => new Room
+            PlaylistItem? item = null;
+            createRoom(() =>
             {
-                Name = { Value = "Test Room" },
-                Playlist =
+                item = new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
                 {
-                    new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
-                    {
-                        RulesetID = new OsuRuleset().RulesetInfo.OnlineID
-                    }
-                }
+                    RulesetID = new OsuRuleset().RulesetInfo.OnlineID
+                };
+                return new Room
+                {
+                    Name = { Value = "Test Room" },
+                    Playlist = { item }
+                };
             });
 
             pressReadyButton();
@@ -419,7 +421,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("Enter song select", () =>
             {
                 var currentSubScreen = ((Screens.OnlinePlay.Multiplayer.Multiplayer)multiplayerComponents.CurrentScreen).CurrentSubScreen;
-                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(multiplayerClient.ClientRoom?.Settings.PlaylistItemId);
+                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(item);
             });
 
             AddUntilStep("wait for song select", () => this.ChildrenOfType<MultiplayerMatchSongSelect>().FirstOrDefault()?.BeatmapSetsLoaded == true);
@@ -440,16 +442,18 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestPlayStartsWithCorrectRulesetWhileAtSongSelect()
         {
-            createRoom(() => new Room
+            PlaylistItem? item = null;
+            createRoom(() =>
             {
-                Name = { Value = "Test Room" },
-                Playlist =
+                item = new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
                 {
-                    new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
-                    {
-                        RulesetID = new OsuRuleset().RulesetInfo.OnlineID
-                    }
-                }
+                    RulesetID = new OsuRuleset().RulesetInfo.OnlineID
+                };
+                return new Room
+                {
+                    Name = { Value = "Test Room" },
+                    Playlist = { item }
+                };
             });
 
             pressReadyButton();
@@ -457,7 +461,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("Enter song select", () =>
             {
                 var currentSubScreen = ((Screens.OnlinePlay.Multiplayer.Multiplayer)multiplayerComponents.CurrentScreen).CurrentSubScreen;
-                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(multiplayerClient.ClientRoom?.Settings.PlaylistItemId);
+                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(item);
             });
 
             AddUntilStep("wait for song select", () => this.ChildrenOfType<MultiplayerMatchSongSelect>().FirstOrDefault()?.BeatmapSetsLoaded == true);
@@ -478,16 +482,18 @@ namespace osu.Game.Tests.Visual.Multiplayer
         [Test]
         public void TestPlayStartsWithCorrectModsWhileAtSongSelect()
         {
-            createRoom(() => new Room
+            PlaylistItem? item = null;
+            createRoom(() =>
             {
-                Name = { Value = "Test Room" },
-                Playlist =
+                item = new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
                 {
-                    new PlaylistItem(beatmaps.GetWorkingBeatmap(importedSet.Beatmaps.First(b => b.Ruleset.OnlineID == 0)).BeatmapInfo)
-                    {
-                        RulesetID = new OsuRuleset().RulesetInfo.OnlineID
-                    }
-                }
+                    RulesetID = new OsuRuleset().RulesetInfo.OnlineID
+                };
+                return new Room
+                {
+                    Name = { Value = "Test Room" },
+                    Playlist = { item }
+                };
             });
 
             pressReadyButton();
@@ -495,7 +501,7 @@ namespace osu.Game.Tests.Visual.Multiplayer
             AddStep("Enter song select", () =>
             {
                 var currentSubScreen = ((Screens.OnlinePlay.Multiplayer.Multiplayer)multiplayerComponents.CurrentScreen).CurrentSubScreen;
-                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(multiplayerClient.ClientRoom?.Settings.PlaylistItemId);
+                ((MultiplayerMatchSubScreen)currentSubScreen).OpenSongSelection(item);
             });
 
             AddUntilStep("wait for song select", () => this.ChildrenOfType<MultiplayerMatchSongSelect>().FirstOrDefault()?.BeatmapSetsLoaded == true);

osu.Game.Tests/Visual/Online/TestSceneScoresContainer.cs

@@ -255,18 +255,25 @@ namespace osu.Game.Tests.Visual.Online
             };
 
             const int initial_great_count = 2000;
+            const int initial_tick_count = 100;
 
             int greatCount = initial_great_count;
+            int tickCount = initial_tick_count;
 
             foreach (var s in scores.Scores)
             {
                 s.Statistics = new Dictionary<HitResult, int>
                 {
-                    { HitResult.Great, greatCount -= 100 },
+                    { HitResult.Great, greatCount },
+                    { HitResult.LargeTickHit, tickCount },
                     { HitResult.Ok, RNG.Next(100) },
                     { HitResult.Meh, RNG.Next(100) },
-                    { HitResult.Miss, initial_great_count - greatCount }
+                    { HitResult.Miss, initial_great_count - greatCount },
+                    { HitResult.LargeTickMiss, initial_tick_count - tickCount },
                 };
+
+                greatCount -= 100;
+                tickCount -= RNG.Next(1, 5);
             }
 
             return scores;

osu.Game.Tests/Visual/SongSelect/TestSceneBeatmapCarousel.cs

@@ -825,7 +825,8 @@ namespace osu.Game.Tests.Visual.SongSelect
             checkVisibleItemCount(true, 15);
         }
 
-        private void loadBeatmaps(List<BeatmapSetInfo> beatmapSets = null, Func<FilterCriteria> initialCriteria = null, Action<BeatmapCarousel> carouselAdjust = null, int? count = null, bool randomDifficulties = false)
+        private void loadBeatmaps(List<BeatmapSetInfo> beatmapSets = null, Func<FilterCriteria> initialCriteria = null, Action<BeatmapCarousel> carouselAdjust = null, int? count = null,
+                                  bool randomDifficulties = false)
         {
             bool changed = false;
 

osu.Game.Tests/Visual/SongSelect/TestSceneUpdateBeatmapSetButton.cs

@@ -0,0 +1,154 @@
+// 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 System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Testing;
+using osu.Game.Beatmaps;
+using osu.Game.Online.API;
+using osu.Game.Screens.Select;
+using osu.Game.Screens.Select.Carousel;
+using osu.Game.Tests.Online;
+using osu.Game.Tests.Resources;
+
+namespace osu.Game.Tests.Visual.SongSelect
+{
+    [TestFixture]
+    public class TestSceneUpdateBeatmapSetButton : OsuManualInputManagerTestScene
+    {
+        private BeatmapCarousel carousel = null!;
+
+        private TestSceneOnlinePlayBeatmapAvailabilityTracker.TestBeatmapModelDownloader beatmapDownloader = null!;
+
+        private BeatmapSetInfo testBeatmapSetInfo = null!;
+
+        protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnlyDependencyContainer parent)
+        {
+            var dependencies = new DependencyContainer(base.CreateChildDependencies(parent));
+
+            var importer = parent.Get<BeatmapManager>();
+
+            dependencies.CacheAs<BeatmapModelDownloader>(beatmapDownloader = new TestSceneOnlinePlayBeatmapAvailabilityTracker.TestBeatmapModelDownloader(importer, API));
+            return dependencies;
+        }
+
+        private UpdateBeatmapSetButton? getUpdateButton() => carousel.ChildrenOfType<UpdateBeatmapSetButton>().SingleOrDefault();
+
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("create carousel", () =>
+            {
+                Child = carousel = new BeatmapCarousel
+                {
+                    RelativeSizeAxes = Axes.Both,
+                    BeatmapSets = new List<BeatmapSetInfo>
+                    {
+                        (testBeatmapSetInfo = TestResources.CreateTestBeatmapSetInfo()),
+                    }
+                };
+            });
+
+            AddUntilStep("wait for load", () => carousel.BeatmapSetsLoaded);
+
+            AddAssert("update button not visible", () => getUpdateButton() == null);
+        }
+
+        [Test]
+        public void TestDownloadToCompletion()
+        {
+            ArchiveDownloadRequest<IBeatmapSetInfo>? downloadRequest = null;
+
+            AddStep("update online hash", () =>
+            {
+                testBeatmapSetInfo.Beatmaps.First().OnlineMD5Hash = "different hash";
+                testBeatmapSetInfo.Beatmaps.First().LastOnlineUpdate = DateTimeOffset.Now;
+
+                carousel.UpdateBeatmapSet(testBeatmapSetInfo);
+            });
+
+            AddUntilStep("update button visible", () => getUpdateButton() != null);
+
+            AddStep("click button", () => getUpdateButton()?.TriggerClick());
+
+            AddUntilStep("wait for download started", () =>
+            {
+                downloadRequest = beatmapDownloader.GetExistingDownload(testBeatmapSetInfo);
+                return downloadRequest != null;
+            });
+
+            AddUntilStep("wait for button disabled", () => getUpdateButton()?.Enabled.Value == false);
+
+            AddUntilStep("progress download to completion", () =>
+            {
+                if (downloadRequest is TestSceneOnlinePlayBeatmapAvailabilityTracker.TestDownloadRequest testRequest)
+                {
+                    testRequest.SetProgress(testRequest.Progress + 0.1f);
+
+                    if (testRequest.Progress >= 1)
+                    {
+                        testRequest.TriggerSuccess();
+
+                        // usually this would be done by the import process.
+                        testBeatmapSetInfo.Beatmaps.First().MD5Hash = "different hash";
+                        testBeatmapSetInfo.Beatmaps.First().LastOnlineUpdate = DateTimeOffset.Now;
+
+                        // usually this would be done by a realm subscription.
+                        carousel.UpdateBeatmapSet(testBeatmapSetInfo);
+                        return true;
+                    }
+                }
+
+                return false;
+            });
+        }
+
+        [Test]
+        public void TestDownloadFailed()
+        {
+            ArchiveDownloadRequest<IBeatmapSetInfo>? downloadRequest = null;
+
+            AddStep("update online hash", () =>
+            {
+                testBeatmapSetInfo.Beatmaps.First().OnlineMD5Hash = "different hash";
+                testBeatmapSetInfo.Beatmaps.First().LastOnlineUpdate = DateTimeOffset.Now;
+
+                carousel.UpdateBeatmapSet(testBeatmapSetInfo);
+            });
+
+            AddUntilStep("update button visible", () => getUpdateButton() != null);
+
+            AddStep("click button", () => getUpdateButton()?.TriggerClick());
+
+            AddUntilStep("wait for download started", () =>
+            {
+                downloadRequest = beatmapDownloader.GetExistingDownload(testBeatmapSetInfo);
+                return downloadRequest != null;
+            });
+
+            AddUntilStep("wait for button disabled", () => getUpdateButton()?.Enabled.Value == false);
+
+            AddUntilStep("progress download to failure", () =>
+            {
+                if (downloadRequest is TestSceneOnlinePlayBeatmapAvailabilityTracker.TestDownloadRequest testRequest)
+                {
+                    testRequest.SetProgress(testRequest.Progress + 0.1f);
+
+                    if (testRequest.Progress >= 0.5f)
+                    {
+                        testRequest.TriggerFailure(new Exception());
+                        return true;
+                    }
+                }
+
+                return false;
+            });
+
+            AddUntilStep("wait for button enabled", () => getUpdateButton()?.Enabled.Value == true);
+        }
+    }
+}

osu.Game.Tests/Visual/UserInterface/TestSceneBeatmapListingSearchControl.cs

@@ -4,13 +4,13 @@
 #nullable disable
 
 using System.Linq;
-using Humanizer;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
+using osu.Game.Extensions;
 using osu.Game.Graphics.Sprites;
 using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Overlays;
@@ -77,7 +77,7 @@ namespace osu.Game.Tests.Visual.UserInterface
             };
 
             control.Query.BindValueChanged(q => query.Text = $"Query: {q.NewValue}", true);
-            control.General.BindCollectionChanged((_, _) => general.Text = $"General: {(control.General.Any() ? string.Join('.', control.General.Select(i => i.ToString().Underscore())) : "")}", true);
+            control.General.BindCollectionChanged((_, _) => general.Text = $"General: {(control.General.Any() ? string.Join('.', control.General.Select(i => i.ToString().ToSnakeCase())) : "")}", true);
             control.Ruleset.BindValueChanged(r => ruleset.Text = $"Ruleset: {r.NewValue}", true);
             control.Category.BindValueChanged(c => category.Text = $"Category: {c.NewValue}", true);
             control.Genre.BindValueChanged(g => genre.Text = $"Genre: {g.NewValue}", true);

osu.Game/Audio/HitSampleInfo.cs

@@ -14,15 +14,15 @@ namespace osu.Game.Audio
     [Serializable]
     public class HitSampleInfo : ISampleInfo, IEquatable<HitSampleInfo>
     {
+        public const string HIT_NORMAL = @"hitnormal";
         public const string HIT_WHISTLE = @"hitwhistle";
         public const string HIT_FINISH = @"hitfinish";
-        public const string HIT_NORMAL = @"hitnormal";
         public const string HIT_CLAP = @"hitclap";
 
         /// <summary>
         /// All valid sample addition constants.
         /// </summary>
-        public static IEnumerable<string> AllAdditions => new[] { HIT_WHISTLE, HIT_CLAP, HIT_FINISH };
+        public static IEnumerable<string> AllAdditions => new[] { HIT_WHISTLE, HIT_FINISH, HIT_CLAP };
 
         /// <summary>
         /// The name of the sample to load.

osu.Game/Beatmaps/BeatmapInfo.cs

@@ -92,6 +92,16 @@ namespace osu.Game.Beatmaps
         [Indexed]
         public string MD5Hash { get; set; } = string.Empty;
 
+        public string OnlineMD5Hash { get; set; } = string.Empty;
+
+        public DateTimeOffset? LastOnlineUpdate { get; set; }
+
+        /// <summary>
+        /// Whether this beatmap matches the online version, based on fetched online metadata.
+        /// Will return <c>true</c> if no online metadata is available.
+        /// </summary>
+        public bool MatchesOnlineVersion => LastOnlineUpdate == null || MD5Hash == OnlineMD5Hash;
+
         [JsonIgnore]
         public bool Hidden { get; set; }
 

osu.Game/Beatmaps/BeatmapModelDownloader.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Database;
 using osu.Game.Online.API;
 using osu.Game.Online.API.Requests;
@@ -14,7 +12,7 @@ namespace osu.Game.Beatmaps
         protected override ArchiveDownloadRequest<IBeatmapSetInfo> CreateDownloadRequest(IBeatmapSetInfo set, bool minimiseDownloadSize) =>
             new DownloadBeatmapSetRequest(set, minimiseDownloadSize);
 
-        public override ArchiveDownloadRequest<IBeatmapSetInfo> GetExistingDownload(IBeatmapSetInfo model)
+        public override ArchiveDownloadRequest<IBeatmapSetInfo>? GetExistingDownload(IBeatmapSetInfo model)
             => CurrentDownloads.Find(r => r.Model.OnlineID == model.OnlineID);
 
         public BeatmapModelDownloader(IModelImporter<BeatmapSetInfo> beatmapImporter, IAPIProvider api)

osu.Game/Beatmaps/BeatmapOnlineChangeIngest.cs

@@ -0,0 +1,50 @@
+// 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.Linq;
+using osu.Framework.Graphics;
+using osu.Game.Database;
+using osu.Game.Online.Metadata;
+
+namespace osu.Game.Beatmaps
+{
+    /// <summary>
+    /// Ingests any changes that happen externally to the client, reprocessing as required.
+    /// </summary>
+    public class BeatmapOnlineChangeIngest : Component
+    {
+        private readonly BeatmapUpdater beatmapUpdater;
+        private readonly RealmAccess realm;
+        private readonly MetadataClient metadataClient;
+
+        public BeatmapOnlineChangeIngest(BeatmapUpdater beatmapUpdater, RealmAccess realm, MetadataClient metadataClient)
+        {
+            this.beatmapUpdater = beatmapUpdater;
+            this.realm = realm;
+            this.metadataClient = metadataClient;
+
+            metadataClient.ChangedBeatmapSetsArrived += changesDetected;
+        }
+
+        private void changesDetected(int[] beatmapSetIds)
+        {
+            // May want to batch incoming updates further if the background realm operations ever becomes a concern.
+            realm.Run(r =>
+            {
+                foreach (int id in beatmapSetIds)
+                {
+                    var matchingSet = r.All<BeatmapSetInfo>().FirstOrDefault(s => s.OnlineID == id);
+
+                    if (matchingSet != null)
+                        beatmapUpdater.Queue(matchingSet.ToLive(realm));
+                }
+            });
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+            metadataClient.ChangedBeatmapSetsArrived -= changesDetected;
+        }
+    }
+}

osu.Game/Beatmaps/BeatmapOnlineLookupQueue.cs

@@ -102,6 +102,10 @@ namespace osu.Game.Beatmaps
 
                     beatmapInfo.BeatmapSet.Status = res.BeatmapSet?.Status ?? BeatmapOnlineStatus.None;
                     beatmapInfo.BeatmapSet.OnlineID = res.OnlineBeatmapSetID;
+
+                    beatmapInfo.OnlineMD5Hash = res.MD5Hash;
+                    beatmapInfo.LastOnlineUpdate = res.LastUpdated;
+
                     beatmapInfo.OnlineID = res.OnlineID;
 
                     beatmapInfo.Metadata.Author.OnlineID = res.AuthorID;
@@ -190,7 +194,7 @@ namespace osu.Game.Beatmaps
 
                     using (var cmd = db.CreateCommand())
                     {
-                        cmd.CommandText = "SELECT beatmapset_id, beatmap_id, approved, user_id FROM osu_beatmaps WHERE checksum = @MD5Hash OR beatmap_id = @OnlineID OR filename = @Path";
+                        cmd.CommandText = "SELECT beatmapset_id, beatmap_id, approved, user_id, checksum, last_update FROM osu_beatmaps WHERE checksum = @MD5Hash OR beatmap_id = @OnlineID OR filename = @Path";
 
                         cmd.Parameters.Add(new SqliteParameter("@MD5Hash", beatmapInfo.MD5Hash));
                         cmd.Parameters.Add(new SqliteParameter("@OnlineID", beatmapInfo.OnlineID));
@@ -209,9 +213,11 @@ namespace osu.Game.Beatmaps
                                 beatmapInfo.BeatmapSet.Status = status;
                                 beatmapInfo.BeatmapSet.OnlineID = reader.GetInt32(0);
                                 beatmapInfo.OnlineID = reader.GetInt32(1);
-
                                 beatmapInfo.Metadata.Author.OnlineID = reader.GetInt32(3);
 
+                                beatmapInfo.OnlineMD5Hash = reader.GetString(4);
+                                beatmapInfo.LastOnlineUpdate = reader.GetDateTimeOffset(5);
+
                                 logForModel(set, $"Cached local retrieval for {beatmapInfo}.");
                                 return true;
                             }

osu.Game/Beatmaps/BeatmapSetInfo.cs

@@ -93,5 +93,7 @@ namespace osu.Game.Beatmaps
         IEnumerable<IBeatmapInfo> IBeatmapSetInfo.Beatmaps => Beatmaps;
 
         IEnumerable<INamedFileUsage> IHasNamedFiles.Files => Files;
+
+        public bool AllBeatmapsUpToDate => Beatmaps.All(b => b.MatchesOnlineVersion);
     }
 }

osu.Game/Beatmaps/BeatmapStatisticIcon.cs

@@ -3,10 +3,10 @@
 
 #nullable disable
 
-using Humanizer;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.Textures;
+using osu.Game.Extensions;
 
 namespace osu.Game.Beatmaps
 {
@@ -25,7 +25,7 @@ namespace osu.Game.Beatmaps
         [BackgroundDependencyLoader]
         private void load(TextureStore textures)
         {
-            Texture = textures.Get($"Icons/BeatmapDetails/{iconType.ToString().Kebaberize()}");
+            Texture = textures.Get($"Icons/BeatmapDetails/{iconType.ToString().ToKebabCase()}");
         }
     }
 

osu.Game/Beatmaps/BeatmapUpdater.cs

@@ -6,6 +6,7 @@ using System.Diagnostics;
 using System.Linq;
 using System.Threading.Tasks;
 using osu.Framework.Extensions.ObjectExtensions;
+using osu.Framework.Logging;
 using osu.Framework.Platform;
 using osu.Game.Database;
 using osu.Game.Online.API;
@@ -30,21 +31,12 @@ namespace osu.Game.Beatmaps
             onlineLookupQueue = new BeatmapOnlineLookupQueue(api, storage);
         }
 
-        /// <summary>
-        /// Queue a beatmap for background processing.
-        /// </summary>
-        public void Queue(int beatmapSetId)
-        {
-            // TODO: implement
-        }
-
         /// <summary>
         /// Queue a beatmap for background processing.
         /// </summary>
         public void Queue(Live<BeatmapSetInfo> beatmap)
         {
-            // For now, just fire off a task.
-            // TODO: Add actual queueing probably.
+            Logger.Log($"Queueing change for local beatmap {beatmap}");
             Task.Factory.StartNew(() => beatmap.PerformRead(Process));
         }
 
@@ -56,6 +48,8 @@ namespace osu.Game.Beatmaps
             // Before we use below, we want to invalidate.
             workingBeatmapCache.Invalidate(beatmapSet);
 
+            // TODO: this call currently uses the local `online.db` lookup.
+            // We probably don't want this to happen after initial import (as the data may be stale).
             onlineLookupQueue.Update(beatmapSet);
 
             foreach (var beatmap in beatmapSet.Beatmaps)

osu.Game/Database/ModelDownloader.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -19,18 +17,18 @@ namespace osu.Game.Database
         where TModel : class, IHasGuidPrimaryKey, ISoftDelete, IEquatable<TModel>, T
         where T : class
     {
-        public Action<Notification> PostNotification { protected get; set; }
+        public Action<Notification>? PostNotification { protected get; set; }
 
-        public event Action<ArchiveDownloadRequest<T>> DownloadBegan;
+        public event Action<ArchiveDownloadRequest<T>>? DownloadBegan;
 
-        public event Action<ArchiveDownloadRequest<T>> DownloadFailed;
+        public event Action<ArchiveDownloadRequest<T>>? DownloadFailed;
 
         private readonly IModelImporter<TModel> importer;
-        private readonly IAPIProvider api;
+        private readonly IAPIProvider? api;
 
         protected readonly List<ArchiveDownloadRequest<T>> CurrentDownloads = new List<ArchiveDownloadRequest<T>>();
 
-        protected ModelDownloader(IModelImporter<TModel> importer, IAPIProvider api)
+        protected ModelDownloader(IModelImporter<TModel> importer, IAPIProvider? api)
         {
             this.importer = importer;
             this.api = api;
@@ -87,7 +85,7 @@ namespace osu.Game.Database
             CurrentDownloads.Add(request);
             PostNotification?.Invoke(notification);
 
-            api.PerformAsync(request);
+            api?.PerformAsync(request);
 
             DownloadBegan?.Invoke(request);
             return true;
@@ -105,7 +103,7 @@ namespace osu.Game.Database
             }
         }
 
-        public abstract ArchiveDownloadRequest<T> GetExistingDownload(T model);
+        public abstract ArchiveDownloadRequest<T>? GetExistingDownload(T model);
 
         private bool canDownload(T model) => GetExistingDownload(model) == null && api != null;
 

osu.Game/Database/RealmAccess.cs

@@ -61,8 +61,9 @@ namespace osu.Game.Database
         /// 15   2022-07-13    Added LastPlayed to BeatmapInfo.
         /// 16   2022-07-15    Removed HasReplay from ScoreInfo.
         /// 17   2022-07-16    Added CountryCode to RealmUser.
+        /// 18   2022-07-19    Added OnlineMD5Hash and LastOnlineUpdate to BeatmapInfo.
         /// </summary>
-        private const int schema_version = 17;
+        private const int schema_version = 18;
 
         /// <summary>
         /// Lock object which is held during <see cref="BlockAllOperations"/> sections, blocking realm retrieval during blocking periods.

osu.Game/Extensions/DrawableExtensions.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 Humanizer;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
@@ -67,7 +66,7 @@ namespace osu.Game.Extensions
 
                 foreach (var (_, property) in component.GetSettingsSourceProperties())
                 {
-                    if (!info.Settings.TryGetValue(property.Name.Underscore(), out object settingValue))
+                    if (!info.Settings.TryGetValue(property.Name.ToSnakeCase(), out object settingValue))
                         continue;
 
                     skinnable.CopyAdjustedSetting((IBindable)property.GetValue(component), settingValue);

osu.Game/Extensions/StringDehumanizeExtensions.cs

@@ -0,0 +1,94 @@
+// 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.
+
+// Based on code from the Humanizer library (https://github.com/Humanizr/Humanizer/blob/606e958cb83afc9be5b36716ac40d4daa9fa73a7/src/Humanizer/InflectorExtensions.cs)
+//
+// Humanizer is licenced under the MIT License (MIT)
+//
+// Copyright (c) .NET Foundation and Contributors
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System.Text.RegularExpressions;
+
+namespace osu.Game.Extensions
+{
+    /// <summary>
+    /// Class with extension methods used to turn human-readable strings to casing conventions frequently used in code.
+    /// Often used for communicating with other systems (web API, spectator server).
+    /// All of the operations in this class are intentionally culture-invariant.
+    /// </summary>
+    public static class StringDehumanizeExtensions
+    {
+        /// <summary>
+        /// Converts the string to "Pascal case" (also known as "upper camel case").
+        /// </summary>
+        /// <example>
+        /// <code>
+        /// "this is a test string".ToPascalCase() == "ThisIsATestString"
+        /// </code>
+        /// </example>
+        public static string ToPascalCase(this string input)
+        {
+            return Regex.Replace(input, "(?:^|_|-| +)(.)", match => match.Groups[1].Value.ToUpperInvariant());
+        }
+
+        /// <summary>
+        /// Converts the string to (lower) "camel case".
+        /// </summary>
+        /// <example>
+        /// <code>
+        /// "this is a test string".ToCamelCase() == "thisIsATestString"
+        /// </code>
+        /// </example>
+        public static string ToCamelCase(this string input)
+        {
+            string word = input.ToPascalCase();
+            return word.Length > 0 ? word.Substring(0, 1).ToLowerInvariant() + word.Substring(1) : word;
+        }
+
+        /// <summary>
+        /// Converts the string to "snake case".
+        /// </summary>
+        /// <example>
+        /// <code>
+        /// "this is a test string".ToSnakeCase() == "this_is_a_test_string"
+        /// </code>
+        /// </example>
+        public static string ToSnakeCase(this string input)
+        {
+            return Regex.Replace(
+                Regex.Replace(
+                    Regex.Replace(input, @"([\p{Lu}]+)([\p{Lu}][\p{Ll}])", "$1_$2"), @"([\p{Ll}\d])([\p{Lu}])", "$1_$2"), @"[-\s]", "_").ToLowerInvariant();
+        }
+
+        /// <summary>
+        /// Converts the string to "kebab case".
+        /// </summary>
+        /// <example>
+        /// <code>
+        /// "this is a test string".ToKebabCase() == "this-is-a-test-string"
+        /// </code>
+        /// </example>
+        public static string ToKebabCase(this string input)
+        {
+            return ToSnakeCase(input).Replace('_', '-');
+        }
+    }
+}

osu.Game/Graphics/Cursor/MenuCursor.cs

@@ -3,21 +3,21 @@
 
 #nullable disable
 
-using osuTK;
+using System;
+using JetBrains.Annotations;
 using osu.Framework.Allocation;
+using osu.Framework.Audio;
+using osu.Framework.Audio.Sample;
+using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Cursor;
 using osu.Framework.Graphics.Sprites;
-using osu.Game.Configuration;
-using System;
-using JetBrains.Annotations;
-using osu.Framework.Audio;
-using osu.Framework.Audio.Sample;
-using osu.Framework.Bindables;
 using osu.Framework.Graphics.Textures;
 using osu.Framework.Input.Events;
 using osu.Framework.Utils;
+using osu.Game.Configuration;
+using osuTK;
 
 namespace osu.Game.Graphics.Cursor
 {
@@ -35,6 +35,7 @@ namespace osu.Game.Graphics.Cursor
         private Vector2 positionMouseDown;
 
         private Sample tapSample;
+        private Vector2 lastMovePosition;
 
         [BackgroundDependencyLoader(true)]
         private void load([NotNull] OsuConfigManager config, [CanBeNull] ScreenshotManager screenshotManager, AudioManager audio)
@@ -47,16 +48,25 @@ namespace osu.Game.Graphics.Cursor
             tapSample = audio.Samples.Get(@"UI/cursor-tap");
         }
 
+        protected override void Update()
+        {
+            base.Update();
+
+            if (dragRotationState != DragRotationState.NotDragging
+                && Vector2.Distance(positionMouseDown, lastMovePosition) > 60)
+            {
+                // make the rotation centre point floating.
+                positionMouseDown = Interpolation.ValueAt(0.04f, positionMouseDown, lastMovePosition, 0, Clock.ElapsedFrameTime);
+            }
+        }
+
         protected override bool OnMouseMove(MouseMoveEvent e)
         {
             if (dragRotationState != DragRotationState.NotDragging)
             {
-                // make the rotation centre point floating.
-                if (Vector2.Distance(positionMouseDown, e.MousePosition) > 60)
-                    positionMouseDown = Interpolation.ValueAt(0.005f, positionMouseDown, e.MousePosition, 0, Clock.ElapsedFrameTime);
+                lastMovePosition = e.MousePosition;
 
-                var position = e.MousePosition;
-                float distance = Vector2Extensions.Distance(position, positionMouseDown);
+                float distance = Vector2Extensions.Distance(lastMovePosition, positionMouseDown);
 
                 // don't start rotating until we're moved a minimum distance away from the mouse down location,
                 // else it can have an annoying effect.

osu.Game/IO/Serialization/SnakeCaseKeyContractResolver.cs

@@ -3,8 +3,8 @@
 
 #nullable disable
 
-using Humanizer;
 using Newtonsoft.Json.Serialization;
+using osu.Game.Extensions;
 
 namespace osu.Game.IO.Serialization
 {
@@ -12,7 +12,7 @@ namespace osu.Game.IO.Serialization
     {
         protected override string ResolvePropertyName(string propertyName)
         {
-            return propertyName.Underscore();
+            return propertyName.ToSnakeCase();
         }
     }
 }

osu.Game/Online/API/APIMod.cs

@@ -7,12 +7,12 @@ using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
-using Humanizer;
 using MessagePack;
 using Newtonsoft.Json;
 using osu.Framework.Bindables;
 using osu.Framework.Logging;
 using osu.Game.Configuration;
+using osu.Game.Extensions;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
 
@@ -45,7 +45,7 @@ namespace osu.Game.Online.API
                 var bindable = (IBindable)property.GetValue(mod);
 
                 if (!bindable.IsDefault)
-                    Settings.Add(property.Name.Underscore(), bindable.GetUnderlyingSettingValue());
+                    Settings.Add(property.Name.ToSnakeCase(), bindable.GetUnderlyingSettingValue());
             }
         }
 
@@ -63,7 +63,7 @@ namespace osu.Game.Online.API
             {
                 foreach (var (_, property) in resultMod.GetSettingsSourceProperties())
                 {
-                    if (!Settings.TryGetValue(property.Name.Underscore(), out object settingValue))
+                    if (!Settings.TryGetValue(property.Name.ToSnakeCase(), out object settingValue))
                         continue;
 
                     try

osu.Game/Online/API/Requests/GetCommentsRequest.cs

@@ -4,7 +4,7 @@
 #nullable disable
 
 using osu.Framework.IO.Network;
-using Humanizer;
+using osu.Game.Extensions;
 using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Overlays.Comments;
 
@@ -32,7 +32,7 @@ namespace osu.Game.Online.API.Requests
             var req = base.CreateWebRequest();
 
             req.AddParameter("commentable_id", commentableId.ToString());
-            req.AddParameter("commentable_type", type.ToString().Underscore().ToLowerInvariant());
+            req.AddParameter("commentable_type", type.ToString().ToSnakeCase().ToLowerInvariant());
             req.AddParameter("page", page.ToString());
             req.AddParameter("sort", sort.ToString().ToLowerInvariant());
 

osu.Game/Online/API/Requests/GetUserBeatmapsRequest.cs

@@ -3,8 +3,8 @@
 
 #nullable disable
 
-using Humanizer;
 using System.Collections.Generic;
+using osu.Game.Extensions;
 using osu.Game.Online.API.Requests.Responses;
 
 namespace osu.Game.Online.API.Requests
@@ -22,7 +22,7 @@ namespace osu.Game.Online.API.Requests
             this.type = type;
         }
 
-        protected override string Target => $@"users/{userId}/beatmapsets/{type.ToString().Underscore()}";
+        protected override string Target => $@"users/{userId}/beatmapsets/{type.ToString().ToSnakeCase()}";
     }
 
     public enum BeatmapSetType

osu.Game/Online/API/Requests/Responses/APIBeatmap.cs

@@ -81,6 +81,9 @@ namespace osu.Game.Online.API.Requests.Responses
         [JsonProperty(@"max_combo")]
         public int? MaxCombo { get; set; }
 
+        [JsonProperty(@"last_updated")]
+        public DateTimeOffset LastUpdated { get; set; }
+
         public double BPM { get; set; }
 
         #region Implementation of IBeatmapInfo

osu.Game/Online/API/Requests/Responses/APIRecentActivity.cs

@@ -4,8 +4,8 @@
 #nullable disable
 
 using System;
-using Humanizer;
 using Newtonsoft.Json;
+using osu.Game.Extensions;
 using osu.Game.Scoring;
 
 namespace osu.Game.Online.API.Requests.Responses
@@ -21,7 +21,7 @@ namespace osu.Game.Online.API.Requests.Responses
         [JsonProperty]
         private string type
         {
-            set => Type = (RecentActivityType)Enum.Parse(typeof(RecentActivityType), value.Pascalize());
+            set => Type = (RecentActivityType)Enum.Parse(typeof(RecentActivityType), value.ToPascalCase());
         }
 
         public RecentActivityType Type;

osu.Game/Online/API/Requests/Responses/APIScoresCollection.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Online.API.Requests.Responses
         [JsonProperty(@"scores")]
         public List<SoloScoreInfo> Scores;
 
-        [JsonProperty(@"userScore")]
+        [JsonProperty(@"user_score")]
         public APIScoreWithPosition UserScore;
     }
 }

osu.Game/Online/API/Requests/SearchBeatmapSetsRequest.cs

@@ -5,7 +5,6 @@
 
 using System.Collections.Generic;
 using System.Linq;
-using Humanizer;
 using JetBrains.Annotations;
 using osu.Framework.IO.Network;
 using osu.Game.Extensions;
@@ -86,7 +85,7 @@ namespace osu.Game.Online.API.Requests
                 req.AddParameter("q", query);
 
             if (General != null && General.Any())
-                req.AddParameter("c", string.Join('.', General.Select(e => e.ToString().Underscore())));
+                req.AddParameter("c", string.Join('.', General.Select(e => e.ToString().ToSnakeCase())));
 
             if (ruleset.OnlineID >= 0)
                 req.AddParameter("m", ruleset.OnlineID.ToString());

osu.Game/Online/HubClientConnector.cs

@@ -64,26 +64,26 @@ namespace osu.Game.Online
             this.preferMessagePack = preferMessagePack;
 
             apiState.BindTo(api.State);
-            apiState.BindValueChanged(_ => connectIfPossible(), true);
+            apiState.BindValueChanged(_ => Task.Run(connectIfPossible), true);
         }
 
-        public void Reconnect()
+        public Task Reconnect()
         {
             Logger.Log($"{clientName} reconnecting...", LoggingTarget.Network);
-            Task.Run(connectIfPossible);
+            return Task.Run(connectIfPossible);
         }
 
-        private void connectIfPossible()
+        private async Task connectIfPossible()
         {
             switch (apiState.Value)
             {
                 case APIState.Failing:
                 case APIState.Offline:
-                    Task.Run(() => disconnect(true));
+                    await disconnect(true);
                     break;
 
                 case APIState.Online:
-                    Task.Run(connect);
+                    await connect();
                     break;
             }
         }

osu.Game/Online/IHubClientConnector.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Threading.Tasks;
 using Microsoft.AspNetCore.SignalR.Client;
 using osu.Framework.Bindables;
 using osu.Game.Online.API;
@@ -32,6 +33,6 @@ namespace osu.Game.Online
         /// <summary>
         /// Reconnect if already connected.
         /// </summary>
-        void Reconnect();
+        Task Reconnect();
     }
 }

osu.Game/Online/Metadata/MetadataClient.cs

@@ -1,6 +1,8 @@
 // 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 System.Linq;
 using System.Threading.Tasks;
 using osu.Framework.Graphics;
 
@@ -11,5 +13,13 @@ namespace osu.Game.Online.Metadata
         public abstract Task BeatmapSetsUpdated(BeatmapUpdates updates);
 
         public abstract Task<BeatmapUpdates> GetChangesSince(int queueId);
+
+        public Action<int[]>? ChangedBeatmapSetsArrived;
+
+        protected Task ProcessChanges(int[] beatmapSetIDs)
+        {
+            ChangedBeatmapSetsArrived?.Invoke(beatmapSetIDs.Distinct().ToArray());
+            return Task.CompletedTask;
+        }
     }
 }

osu.Game/Online/Metadata/OnlineMetadataClient.cs

@@ -7,7 +7,6 @@ using Microsoft.AspNetCore.SignalR.Client;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Logging;
-using osu.Game.Beatmaps;
 using osu.Game.Configuration;
 using osu.Game.Online.API;
 
@@ -15,7 +14,6 @@ namespace osu.Game.Online.Metadata
 {
     public class OnlineMetadataClient : MetadataClient
     {
-        private readonly BeatmapUpdater beatmapUpdater;
         private readonly string endpoint;
 
         private IHubClientConnector? connector;
@@ -24,9 +22,8 @@ namespace osu.Game.Online.Metadata
 
         private HubConnection? connection => connector?.CurrentConnection;
 
-        public OnlineMetadataClient(EndpointConfiguration endpoints, BeatmapUpdater beatmapUpdater)
+        public OnlineMetadataClient(EndpointConfiguration endpoints)
         {
-            this.beatmapUpdater = beatmapUpdater;
             endpoint = endpoints.MetadataEndpointUrl;
         }
 
@@ -102,17 +99,6 @@ namespace osu.Game.Online.Metadata
             await ProcessChanges(updates.BeatmapSetIDs);
         }
 
-        protected Task ProcessChanges(int[] beatmapSetIDs)
-        {
-            foreach (int id in beatmapSetIDs)
-            {
-                Logger.Log($"Processing {id}...");
-                beatmapUpdater.Queue(id);
-            }
-
-            return Task.CompletedTask;
-        }
-
         public override Task<BeatmapUpdates> GetChangesSince(int queueId)
         {
             if (connector?.IsConnected.Value != true)

osu.Game/Online/Multiplayer/MultiplayerClient.cs

@@ -21,7 +21,6 @@ using osu.Game.Online.Rooms.RoomStatuses;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Utils;
-using APIUser = osu.Game.Online.API.Requests.Responses.APIUser;
 
 namespace osu.Game.Online.Multiplayer
 {
@@ -91,7 +90,7 @@ namespace osu.Game.Online.Multiplayer
         /// <summary>
         /// The joined <see cref="MultiplayerRoom"/>.
         /// </summary>
-        public virtual MultiplayerRoom? Room
+        public virtual MultiplayerRoom? Room // virtual for moq
         {
             get
             {
@@ -150,7 +149,7 @@ namespace osu.Game.Online.Multiplayer
                 // clean up local room state on server disconnect.
                 if (!connected.NewValue && Room != null)
                 {
-                    Logger.Log("Connection to multiplayer server was lost.", LoggingTarget.Runtime, LogLevel.Important);
+                    Logger.Log("Clearing room due to multiplayer server connection loss.", LoggingTarget.Runtime, LogLevel.Important);
                     LeaveRoom();
                 }
             }));

osu.Game/Online/Multiplayer/OnlineMultiplayerClient.cs

@@ -85,7 +85,13 @@ namespace osu.Game.Online.Multiplayer
             catch (HubException exception)
             {
                 if (exception.GetHubExceptionMessage() == HubClientConnector.SERVER_SHUTDOWN_MESSAGE)
-                    connector?.Reconnect();
+                {
+                    Debug.Assert(connector != null);
+
+                    await connector.Reconnect();
+                    return await JoinRoom(roomId, password);
+                }
+
                 throw;
             }
         }

osu.Game/Online/Rooms/GetRoomsRequest.cs

@@ -4,8 +4,8 @@
 #nullable disable
 
 using System.Collections.Generic;
-using Humanizer;
 using osu.Framework.IO.Network;
+using osu.Game.Extensions;
 using osu.Game.Online.API;
 using osu.Game.Screens.OnlinePlay.Lounge.Components;
 
@@ -27,7 +27,7 @@ namespace osu.Game.Online.Rooms
             var req = base.CreateWebRequest();
 
             if (status != RoomStatusFilter.Open)
-                req.AddParameter("mode", status.ToString().Underscore().ToLowerInvariant());
+                req.AddParameter("mode", status.ToString().ToSnakeCase().ToLowerInvariant());
 
             if (!string.IsNullOrEmpty(category))
                 req.AddParameter("category", category);

osu.Game/Online/Spectator/OnlineSpectatorClient.cs

@@ -61,8 +61,15 @@ namespace osu.Game.Online.Spectator
             catch (HubException exception)
             {
                 if (exception.GetHubExceptionMessage() == HubClientConnector.SERVER_SHUTDOWN_MESSAGE)
-                    connector?.Reconnect();
-                throw;
+                {
+                    Debug.Assert(connector != null);
+
+                    await connector.Reconnect();
+                    await BeginPlayingInternal(state);
+                }
+
+                // Exceptions can occur if, for instance, the locally played beatmap doesn't have a server-side counterpart.
+                // For now, let's ignore these so they don't cause unobserved exceptions to appear to the user (and sentry).
             }
         }
 

osu.Game/OsuGameBase.cs

@@ -287,7 +287,9 @@ namespace osu.Game
 
             dependencies.CacheAs(spectatorClient = new OnlineSpectatorClient(endpoints));
             dependencies.CacheAs(multiplayerClient = new OnlineMultiplayerClient(endpoints));
-            dependencies.CacheAs(metadataClient = new OnlineMetadataClient(endpoints, beatmapUpdater));
+            dependencies.CacheAs(metadataClient = new OnlineMetadataClient(endpoints));
+
+            AddInternal(new BeatmapOnlineChangeIngest(beatmapUpdater, realm, metadataClient));
 
             BeatmapManager.ProcessBeatmap = set => beatmapUpdater.Process(set);
 

osu.Game/Overlays/BeatmapSet/Scores/ScoreTable.cs

@@ -23,6 +23,7 @@ using osuTK;
 using osuTK.Graphics;
 using osu.Framework.Localisation;
 using osu.Framework.Extensions.LocalisationExtensions;
+using osu.Framework.Graphics.Cursor;
 using osu.Game.Resources.Localisation.Web;
 
 namespace osu.Game.Overlays.BeatmapSet.Scores
@@ -38,8 +39,6 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
 
         private readonly FillFlowContainer backgroundFlow;
 
-        private Color4 highAccuracyColour;
-
         public ScoreTable()
         {
             RelativeSizeAxes = Axes.X;
@@ -57,12 +56,6 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
             });
         }
 
-        [BackgroundDependencyLoader]
-        private void load(OsuColour colours)
-        {
-            highAccuracyColour = colours.GreenLight;
-        }
-
         /// <summary>
         /// The statistics that appear in the table, in order of appearance.
         /// </summary>
@@ -158,12 +151,10 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                     Current = scoreManager.GetBindableTotalScoreString(score),
                     Font = OsuFont.GetFont(size: text_size, weight: index == 0 ? FontWeight.Bold : FontWeight.Medium)
                 },
-                new OsuSpriteText
+                new StatisticText(score.Accuracy, 1, showTooltip: false)
                 {
                     Margin = new MarginPadding { Right = horizontal_inset },
                     Text = score.DisplayAccuracy,
-                    Font = OsuFont.GetFont(size: text_size),
-                    Colour = score.Accuracy == 1 ? highAccuracyColour : Color4.White
                 },
                 new UpdateableFlag(score.User.CountryCode)
                 {
@@ -171,14 +162,9 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                     ShowPlaceholderOnUnknown = false,
                 },
                 username,
-                new OsuSpriteText
-                {
-                    Text = score.MaxCombo.ToLocalisableString(@"0\x"),
-                    Font = OsuFont.GetFont(size: text_size),
 #pragma warning disable 618
-                    Colour = score.MaxCombo == score.BeatmapInfo.MaxCombo ? highAccuracyColour : Color4.White
+                new StatisticText(score.MaxCombo, score.BeatmapInfo.MaxCombo, @"0\x"),
 #pragma warning restore 618
-                }
             };
 
             var availableStatistics = score.GetStatisticsForDisplay().ToDictionary(tuple => tuple.Result);
@@ -188,23 +174,13 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                 if (!availableStatistics.TryGetValue(result.result, out var stat))
                     stat = new HitResultDisplayStatistic(result.result, 0, null, result.displayName);
 
-                content.Add(new OsuSpriteText
-                {
-                    Text = stat.MaxCount == null ? stat.Count.ToLocalisableString(@"N0") : (LocalisableString)$"{stat.Count}/{stat.MaxCount}",
-                    Font = OsuFont.GetFont(size: text_size),
-                    Colour = stat.Count == 0 ? Color4.Gray : Color4.White
-                });
+                content.Add(new StatisticText(stat.Count, stat.MaxCount, @"N0") { Colour = stat.Count == 0 ? Color4.Gray : Color4.White });
             }
 
             if (showPerformancePoints)
             {
                 Debug.Assert(score.PP != null);
-
-                content.Add(new OsuSpriteText
-                {
-                    Text = score.PP.ToLocalisableString(@"N0"),
-                    Font = OsuFont.GetFont(size: text_size)
-                });
+                content.Add(new StatisticText(score.PP.Value, format: @"N0"));
             }
 
             content.Add(new ScoreboardTime(score.Date, text_size)
@@ -243,5 +219,31 @@ namespace osu.Game.Overlays.BeatmapSet.Scores
                 Colour = colourProvider.Foreground1;
             }
         }
+
+        private class StatisticText : OsuSpriteText, IHasTooltip
+        {
+            private readonly double count;
+            private readonly double? maxCount;
+            private readonly bool showTooltip;
+
+            public LocalisableString TooltipText => maxCount == null || !showTooltip ? string.Empty : $"{count}/{maxCount}";
+
+            public StatisticText(double count, double? maxCount = null, string format = null, bool showTooltip = true)
+            {
+                this.count = count;
+                this.maxCount = maxCount;
+                this.showTooltip = showTooltip;
+
+                Text = count.ToLocalisableString(format);
+                Font = OsuFont.GetFont(size: text_size);
+            }
+
+            [BackgroundDependencyLoader]
+            private void load(OsuColour colours)
+            {
+                if (count == maxCount)
+                    Colour = colours.GreenLight;
+            }
+        }
     }
 }

osu.Game/Rulesets/Mods/DifficultyBindable.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
@@ -29,7 +27,7 @@ namespace osu.Game.Rulesets.Mods
         /// <summary>
         /// A function that can extract the current value of this setting from a beatmap difficulty for display purposes.
         /// </summary>
-        public Func<IBeatmapDifficultyInfo, float> ReadCurrentFromDifficulty;
+        public Func<IBeatmapDifficultyInfo, float>? ReadCurrentFromDifficulty;
 
         public float Precision
         {

osu.Game/Rulesets/Mods/IApplicableAfterBeatmapConversion.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableFailOverride.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Mods
 {
     /// <summary>

osu.Game/Rulesets/Mods/IApplicableMod.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Mods
 {
     /// <summary>

osu.Game/Rulesets/Mods/IApplicableToAudio.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Mods
 {
     public interface IApplicableToAudio : IApplicableToTrack, IApplicableToSample

osu.Game/Rulesets/Mods/IApplicableToBeatmap.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToBeatmapConverter.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToBeatmapProcessor.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToDifficulty.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Beatmaps;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToDrawableHitObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Objects.Drawables;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToDrawableHitObjects.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using osu.Framework.Extensions.IEnumerableExtensions;

osu.Game/Rulesets/Mods/IApplicableToDrawableRuleset.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.UI;
 

osu.Game/Rulesets/Mods/IApplicableToHUD.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Screens.Play;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToHealthProcessor.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToHitObject.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Objects;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToPlayer.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Screens.Play;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToRate.cs

@@ -1,8 +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.
 
-#nullable disable
-
 namespace osu.Game.Rulesets.Mods
 {
     /// <summary>

osu.Game/Rulesets/Mods/IApplicableToSample.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Audio;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IApplicableToScoreProcessor.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.Scoring;
 using osu.Game.Scoring;
 

osu.Game/Rulesets/Mods/IApplicableToTrack.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Audio;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/ICreateReplay.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using osu.Game.Beatmaps;

osu.Game/Rulesets/Mods/ICreateReplayData.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Online.API.Requests.Responses;
@@ -45,7 +43,7 @@ namespace osu.Game.Rulesets.Mods
         /// </summary>
         public readonly ModCreatedUser User;
 
-        public ModReplayData(Replay replay, ModCreatedUser user = null)
+        public ModReplayData(Replay replay, ModCreatedUser? user = null)
         {
             Replay = replay;
             User = user ?? new ModCreatedUser();

osu.Game/Rulesets/Mods/IHasSeed.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Bindables;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IMod.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Graphics.Sprites;
 

osu.Game/Rulesets/Mods/IReadFromConfig.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Configuration;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/IUpdatableByPlayfield.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Game.Rulesets.UI;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/MetronomeBeat.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Audio;
 using osu.Framework.Audio.Track;
 using osu.Framework.Bindables;

osu.Game/Rulesets/Mods/Mod.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -117,7 +115,7 @@ namespace osu.Game.Rulesets.Mods
         [JsonIgnore]
         public virtual Type[] IncompatibleMods => Array.Empty<Type>();
 
-        private IReadOnlyList<IBindable> settingsBacking;
+        private IReadOnlyList<IBindable>? settingsBacking;
 
         /// <summary>
         /// A list of the all <see cref="IBindable"/> settings within this mod.
@@ -216,8 +214,8 @@ namespace osu.Game.Rulesets.Mods
 
             public bool Equals(IBindable x, IBindable y)
             {
-                object xValue = x?.GetUnderlyingSettingValue();
-                object yValue = y?.GetUnderlyingSettingValue();
+                object xValue = x.GetUnderlyingSettingValue();
+                object yValue = y.GetUnderlyingSettingValue();
 
                 return EqualityComparer<object>.Default.Equals(xValue, yValue);
             }

osu.Game/Rulesets/Mods/ModAdaptiveSpeed.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -79,7 +77,7 @@ namespace osu.Game.Rulesets.Mods
         // Apply a fixed rate change when missing, allowing the player to catch up when the rate is too fast.
         private const double rate_change_on_miss = 0.95d;
 
-        private IAdjustableAudioComponent track;
+        private IAdjustableAudioComponent? track;
         private double targetRate = 1d;
 
         /// <summary>

osu.Game/Rulesets/Mods/ModAutoplay.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using osu.Framework.Graphics.Sprites;

osu.Game/Rulesets/Mods/ModBarrelRoll.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Bindables;
 using osu.Framework.Extensions;

osu.Game/Rulesets/Mods/ModBlockFail.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Bindables;
 using osu.Game.Configuration;
 using osu.Game.Screens.Play;
@@ -11,7 +9,7 @@ namespace osu.Game.Rulesets.Mods
 {
     public abstract class ModBlockFail : Mod, IApplicableFailOverride, IApplicableToHUD, IReadFromConfig
     {
-        private Bindable<bool> showHealthBar;
+        private readonly Bindable<bool> showHealthBar = new Bindable<bool>();
 
         /// <summary>
         /// We never fail, 'yo.
@@ -22,7 +20,7 @@ namespace osu.Game.Rulesets.Mods
 
         public void ReadFromConfig(OsuConfigManager config)
         {
-            showHealthBar = config.GetBindable<bool>(OsuSetting.ShowHealthDisplayWhenCantFail);
+            config.BindWith(OsuSetting.ShowHealthDisplayWhenCantFail, showHealthBar);
         }
 
         public void ApplyToHUD(HUDOverlay overlay)

osu.Game/Rulesets/Mods/ModCinema.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Linq;
 using osu.Framework.Graphics.Sprites;

osu.Game/Rulesets/Mods/ModClassic.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Graphics.Sprites;
 
 namespace osu.Game.Rulesets.Mods

osu.Game/Rulesets/Mods/ModDaycore.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Audio;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics.Sprites;

osu.Game/Rulesets/Mods/ModDifficultyAdjust.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using System.Linq;
 using osu.Framework.Bindables;

osu.Game/Rulesets/Mods/ModDoubleTime.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using osu.Framework.Bindables;
 using osu.Framework.Graphics.Sprites;
 using osu.Game.Configuration;

osu.Game/Rulesets/Mods/ModEasy.cs

@@ -1,8 +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.
 
-#nullable disable
-
 using System;
 using osu.Framework.Graphics.Sprites;
 using osu.Game.Beatmaps;