Merge branch 'master' into fl-slider

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="2022.715.0" />
+    <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/OsuGameDesktop.cs

@@ -22,10 +22,12 @@ using osu.Framework.Input.Handlers;
 using osu.Framework.Input.Handlers.Joystick;
 using osu.Framework.Input.Handlers.Mouse;
 using osu.Framework.Input.Handlers.Tablet;
+using osu.Framework.Input.Handlers.Touch;
 using osu.Framework.Threading;
 using osu.Game.IO;
 using osu.Game.IPC;
 using osu.Game.Overlays.Settings;
+using osu.Game.Overlays.Settings.Sections;
 using osu.Game.Overlays.Settings.Sections.Input;
 
 namespace osu.Desktop
@@ -156,6 +158,9 @@ namespace osu.Desktop
                 case JoystickHandler jh:
                     return new JoystickSettings(jh);
 
+                case TouchHandler th:
+                    return new InputSection.HandlerSection(th);
+
                 default:
                     return base.CreateSettingsSubsectionFor(handler);
             }

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/Mods/CatchModDoubleTime.cs

@@ -9,6 +9,6 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModDoubleTime : ModDoubleTime
     {
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
     }
 }

osu.Game.Rulesets.Catch/Mods/CatchModFlashlight.cs

@@ -16,7 +16,7 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModFlashlight : ModFlashlight<CatchHitObject>
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
 
         [SettingSource("Flashlight size", "Multiplier applied to the default flashlight size.")]
         public override BindableFloat SizeMultiplier { get; } = new BindableFloat

osu.Game.Rulesets.Catch/Mods/CatchModHardRock.cs

@@ -11,7 +11,7 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModHardRock : ModHardRock, IApplicableToBeatmapProcessor
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
 
         public void ApplyToBeatmapProcessor(IBeatmapProcessor beatmapProcessor)
         {

osu.Game.Rulesets.Catch/Mods/CatchModHidden.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Rulesets.Catch.Mods
     public class CatchModHidden : ModHidden, IApplicableToDrawableRuleset<CatchHitObject>
     {
         public override string Description => @"Play with fading fruits.";
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
 
         private const double fade_out_offset_multiplier = 0.6;
         private const double fade_out_duration_multiplier = 0.44;

osu.Game.Rulesets.Catch/Mods/CatchModNightcore.cs

@@ -10,6 +10,6 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModNightcore : ModNightcore<CatchHitObject>
     {
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
     }
 }

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/Mods/OsuModBlinds.cs

@@ -30,7 +30,7 @@ namespace osu.Game.Rulesets.Osu.Mods
         public override IconUsage? Icon => FontAwesome.Solid.Adjust;
         public override ModType Type => ModType.DifficultyIncrease;
 
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
         public override Type[] IncompatibleMods => new[] { typeof(OsuModFlashlight) };
 
         private DrawableOsuBlinds blinds;

osu.Game.Rulesets.Osu/Mods/OsuModCinema.cs

@@ -15,7 +15,7 @@ namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModCinema : ModCinema<OsuHitObject>
     {
-        public override Type[] IncompatibleMods => base.IncompatibleMods.Concat(new[] { typeof(OsuModMagnetised), typeof(OsuModAutopilot), typeof(OsuModSpunOut), typeof(OsuModAlternate), typeof(OsuModSingleTap) }).ToArray();
+        public override Type[] IncompatibleMods => base.IncompatibleMods.Concat(new[] { typeof(OsuModMagnetised), typeof(OsuModAutopilot), typeof(OsuModSpunOut), typeof(OsuModAlternate), typeof(OsuModSingleTap), typeof(OsuModRepel) }).ToArray();
 
         public override ModReplayData CreateReplayData(IBeatmap beatmap, IReadOnlyList<Mod> mods)
             => new ModReplayData(new OsuAutoGenerator(beatmap, mods).Generate(), new ModCreatedUser { Username = "Autoplay" });

osu.Game.Rulesets.Osu/Mods/OsuModDoubleTime.cs

@@ -9,6 +9,6 @@ namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModDoubleTime : ModDoubleTime
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
     }
 }

osu.Game.Rulesets.Osu/Mods/OsuModFlashlight.cs

@@ -21,7 +21,7 @@ namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModFlashlight : ModFlashlight<OsuHitObject>, IApplicableToDrawableHitObject
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(OsuModBlinds)).ToArray();
 
         private const double default_follow_delay = 120;

osu.Game.Rulesets.Osu/Mods/OsuModHardRock.cs

@@ -14,7 +14,7 @@ namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModHardRock : ModHardRock, IApplicableToHitObject
     {
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
 
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(ModMirror)).ToArray();
 

osu.Game.Rulesets.Osu/Mods/OsuModHidden.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Rulesets.Osu.Mods
         public Bindable<bool> OnlyFadeApproachCircles { get; } = new BindableBool();
 
         public override string Description => @"Play with no approach circles and fading circles/sliders.";
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
 
         public override Type[] IncompatibleMods => new[] { typeof(IRequiresApproachCircles), typeof(OsuModSpinIn) };
 

osu.Game.Rulesets.Osu/Mods/OsuModNightcore.cs

@@ -10,6 +10,6 @@ namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModNightcore : ModNightcore<OsuHitObject>
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
     }
 }

osu.Game.Rulesets.Osu/Mods/OsuModPerfect.cs

@@ -3,11 +3,14 @@
 
 #nullable disable
 
+using System;
+using System.Linq;
 using osu.Game.Rulesets.Mods;
 
 namespace osu.Game.Rulesets.Osu.Mods
 {
     public class OsuModPerfect : ModPerfect
     {
+        public override Type[] IncompatibleMods => base.IncompatibleMods.Concat(new[] { typeof(OsuModAutopilot) }).ToArray();
     }
 }

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.Tests/TestSceneTaikoPlayerLegacySkin.cs

@@ -0,0 +1,19 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Game.Rulesets.Taiko.Mods;
+using osu.Game.Tests.Visual;
+
+namespace osu.Game.Rulesets.Taiko.Tests
+{
+    public class TestSceneTaikoPlayerLegacySkin : LegacySkinPlayerTestScene
+    {
+        protected override Ruleset CreatePlayerRuleset() => new TaikoRuleset();
+
+        protected override TestPlayer CreatePlayer(Ruleset ruleset)
+        {
+            SelectedMods.Value = new[] { new TaikoModClassic() };
+            return base.CreatePlayer(ruleset);
+        }
+    }
+}

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/Mods/TaikoModClassic.cs

@@ -18,6 +18,9 @@ namespace osu.Game.Rulesets.Taiko.Mods
         {
             drawableTaikoRuleset = (DrawableTaikoRuleset)drawableRuleset;
             drawableTaikoRuleset.LockPlayfieldAspect.Value = false;
+
+            var playfield = (TaikoPlayfield)drawableRuleset.Playfield;
+            playfield.ClassicHitTargetPosition.Value = true;
         }
 
         public void Update(Playfield playfield)

osu.Game.Rulesets.Taiko/Mods/TaikoModDoubleTime.cs

@@ -9,6 +9,6 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModDoubleTime : ModDoubleTime
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
     }
 }

osu.Game.Rulesets.Taiko/Mods/TaikoModFlashlight.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModFlashlight : ModFlashlight<TaikoHitObject>
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
 
         [SettingSource("Flashlight size", "Multiplier applied to the default flashlight size.")]
         public override BindableFloat SizeMultiplier { get; } = new BindableFloat

osu.Game.Rulesets.Taiko/Mods/TaikoModHardRock.cs

@@ -10,7 +10,7 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModHardRock : ModHardRock
     {
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
 
         /// <summary>
         /// Multiplier factor added to the scrolling speed.

osu.Game.Rulesets.Taiko/Mods/TaikoModHidden.cs

@@ -18,7 +18,7 @@ namespace osu.Game.Rulesets.Taiko.Mods
     public class TaikoModHidden : ModHidden, IApplicableToDrawableRuleset<TaikoHitObject>
     {
         public override string Description => @"Beats fade out before you hit them!";
-        public override double ScoreMultiplier => 1.06;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.06 : 1;
 
         /// <summary>
         /// How far away from the hit target should hitobjects start to fade out.

osu.Game.Rulesets.Taiko/Mods/TaikoModNightcore.cs

@@ -10,6 +10,6 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModNightcore : ModNightcore<TaikoHitObject>
     {
-        public override double ScoreMultiplier => 1.12;
+        public override double ScoreMultiplier => UsesDefaultConfiguration ? 1.12 : 1;
     }
 }

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.Rulesets.Taiko/Skinning/Legacy/LegacyInputDrum.cs

@@ -22,13 +22,14 @@ namespace osu.Game.Rulesets.Taiko.Skinning.Legacy
     /// </summary>
     internal class LegacyInputDrum : Container
     {
+        private Container content;
         private LegacyHalfDrum left;
         private LegacyHalfDrum right;
-        private Container content;
 
         public LegacyInputDrum()
         {
-            RelativeSizeAxes = Axes.Both;
+            RelativeSizeAxes = Axes.Y;
+            AutoSizeAxes = Axes.X;
         }
 
         [BackgroundDependencyLoader]

osu.Game.Rulesets.Taiko/UI/InputDrum.cs

@@ -14,6 +14,7 @@ using osu.Framework.Input.Events;
 using osu.Game.Graphics;
 using osu.Game.Rulesets.Taiko.Objects;
 using osu.Game.Rulesets.UI;
+using osu.Game.Screens.Ranking;
 using osu.Game.Skinning;
 using osuTK;
 
@@ -33,7 +34,8 @@ namespace osu.Game.Rulesets.Taiko.UI
         {
             sampleTriggerSource = new DrumSampleTriggerSource(hitObjectContainer);
 
-            RelativeSizeAxes = Axes.Both;
+            AutoSizeAxes = Axes.X;
+            RelativeSizeAxes = Axes.Y;
         }
 
         [BackgroundDependencyLoader]
@@ -41,12 +43,32 @@ namespace osu.Game.Rulesets.Taiko.UI
         {
             Children = new Drawable[]
             {
-                new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.InputDrum), _ => new Container
+                new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.InputDrum), _ => new DefaultInputDrum())
                 {
+                    RelativeSizeAxes = Axes.Y,
+                    AutoSizeAxes = Axes.X,
+                },
+                sampleTriggerSource
+            };
+        }
+
+        private class DefaultInputDrum : AspectContainer
+        {
+            public DefaultInputDrum()
+            {
+                RelativeSizeAxes = Axes.Y;
+            }
+
+            [BackgroundDependencyLoader]
+            private void load()
+            {
+                InternalChild = new Container
+                {
+                    Anchor = Anchor.Centre,
+                    Origin = Anchor.Centre,
                     RelativeSizeAxes = Axes.Both,
-                    FillMode = FillMode.Fit,
                     Scale = new Vector2(0.9f),
-                    Children = new Drawable[]
+                    Children = new[]
                     {
                         new TaikoHalfDrum(false)
                         {
@@ -71,131 +93,130 @@ namespace osu.Game.Rulesets.Taiko.UI
                             CentreAction = TaikoAction.RightCentre
                         }
                     }
-                }),
-                sampleTriggerSource
-            };
-        }
-
-        /// <summary>
-        /// A half-drum. Contains one centre and one rim hit.
-        /// </summary>
-        private class TaikoHalfDrum : Container, IKeyBindingHandler<TaikoAction>
-        {
-            /// <summary>
-            /// The key to be used for the rim of the half-drum.
-            /// </summary>
-            public TaikoAction RimAction;
-
-            /// <summary>
-            /// The key to be used for the centre of the half-drum.
-            /// </summary>
-            public TaikoAction CentreAction;
-
-            private readonly Sprite rim;
-            private readonly Sprite rimHit;
-            private readonly Sprite centre;
-            private readonly Sprite centreHit;
-
-            [Resolved]
-            private DrumSampleTriggerSource sampleTriggerSource { get; set; }
-
-            public TaikoHalfDrum(bool flipped)
-            {
-                Masking = true;
-
-                Children = new Drawable[]
-                {
-                    rim = new Sprite
-                    {
-                        Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
-                        Origin = Anchor.Centre,
-                        RelativeSizeAxes = Axes.Both
-                    },
-                    rimHit = new Sprite
-                    {
-                        Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
-                        Origin = Anchor.Centre,
-                        RelativeSizeAxes = Axes.Both,
-                        Alpha = 0,
-                        Blending = BlendingParameters.Additive,
-                    },
-                    centre = new Sprite
-                    {
-                        Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
-                        Origin = Anchor.Centre,
-                        RelativeSizeAxes = Axes.Both,
-                        Size = new Vector2(0.7f)
-                    },
-                    centreHit = new Sprite
-                    {
-                        Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
-                        Origin = Anchor.Centre,
-                        RelativeSizeAxes = Axes.Both,
-                        Size = new Vector2(0.7f),
-                        Alpha = 0,
-                        Blending = BlendingParameters.Additive
-                    }
                 };
             }
 
-            [BackgroundDependencyLoader]
-            private void load(TextureStore textures, OsuColour colours)
+            /// <summary>
+            /// A half-drum. Contains one centre and one rim hit.
+            /// </summary>
+            private class TaikoHalfDrum : Container, IKeyBindingHandler<TaikoAction>
             {
-                rim.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-outer");
-                rimHit.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-outer-hit");
-                centre.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-inner");
-                centreHit.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-inner-hit");
+                /// <summary>
+                /// The key to be used for the rim of the half-drum.
+                /// </summary>
+                public TaikoAction RimAction;
 
-                rimHit.Colour = colours.Blue;
-                centreHit.Colour = colours.Pink;
-            }
+                /// <summary>
+                /// The key to be used for the centre of the half-drum.
+                /// </summary>
+                public TaikoAction CentreAction;
 
-            public bool OnPressed(KeyBindingPressEvent<TaikoAction> e)
-            {
-                Drawable target = null;
-                Drawable back = null;
+                private readonly Sprite rim;
+                private readonly Sprite rimHit;
+                private readonly Sprite centre;
+                private readonly Sprite centreHit;
 
-                if (e.Action == CentreAction)
+                [Resolved]
+                private DrumSampleTriggerSource sampleTriggerSource { get; set; }
+
+                public TaikoHalfDrum(bool flipped)
                 {
-                    target = centreHit;
-                    back = centre;
+                    Masking = true;
 
-                    sampleTriggerSource.Play(HitType.Centre);
-                }
-                else if (e.Action == RimAction)
-                {
-                    target = rimHit;
-                    back = rim;
-
-                    sampleTriggerSource.Play(HitType.Rim);
+                    Children = new Drawable[]
+                    {
+                        rim = new Sprite
+                        {
+                            Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
+                            Origin = Anchor.Centre,
+                            RelativeSizeAxes = Axes.Both
+                        },
+                        rimHit = new Sprite
+                        {
+                            Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
+                            Origin = Anchor.Centre,
+                            RelativeSizeAxes = Axes.Both,
+                            Alpha = 0,
+                            Blending = BlendingParameters.Additive,
+                        },
+                        centre = new Sprite
+                        {
+                            Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
+                            Origin = Anchor.Centre,
+                            RelativeSizeAxes = Axes.Both,
+                            Size = new Vector2(0.7f)
+                        },
+                        centreHit = new Sprite
+                        {
+                            Anchor = flipped ? Anchor.CentreLeft : Anchor.CentreRight,
+                            Origin = Anchor.Centre,
+                            RelativeSizeAxes = Axes.Both,
+                            Size = new Vector2(0.7f),
+                            Alpha = 0,
+                            Blending = BlendingParameters.Additive
+                        }
+                    };
                 }
 
-                if (target != null)
+                [BackgroundDependencyLoader]
+                private void load(TextureStore textures, OsuColour colours)
                 {
-                    const float scale_amount = 0.05f;
-                    const float alpha_amount = 0.5f;
+                    rim.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-outer");
+                    rimHit.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-outer-hit");
+                    centre.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-inner");
+                    centreHit.Texture = textures.Get(@"Gameplay/taiko/taiko-drum-inner-hit");
 
-                    const float down_time = 40;
-                    const float up_time = 1000;
-
-                    back.ScaleTo(target.Scale.X - scale_amount, down_time, Easing.OutQuint)
-                        .Then()
-                        .ScaleTo(1, up_time, Easing.OutQuint);
-
-                    target.Animate(
-                        t => t.ScaleTo(target.Scale.X - scale_amount, down_time, Easing.OutQuint),
-                        t => t.FadeTo(Math.Min(target.Alpha + alpha_amount, 1), down_time, Easing.OutQuint)
-                    ).Then(
-                        t => t.ScaleTo(1, up_time, Easing.OutQuint),
-                        t => t.FadeOut(up_time, Easing.OutQuint)
-                    );
+                    rimHit.Colour = colours.Blue;
+                    centreHit.Colour = colours.Pink;
                 }
 
-                return false;
-            }
+                public bool OnPressed(KeyBindingPressEvent<TaikoAction> e)
+                {
+                    Drawable target = null;
+                    Drawable back = null;
 
-            public void OnReleased(KeyBindingReleaseEvent<TaikoAction> e)
-            {
+                    if (e.Action == CentreAction)
+                    {
+                        target = centreHit;
+                        back = centre;
+
+                        sampleTriggerSource.Play(HitType.Centre);
+                    }
+                    else if (e.Action == RimAction)
+                    {
+                        target = rimHit;
+                        back = rim;
+
+                        sampleTriggerSource.Play(HitType.Rim);
+                    }
+
+                    if (target != null)
+                    {
+                        const float scale_amount = 0.05f;
+                        const float alpha_amount = 0.5f;
+
+                        const float down_time = 40;
+                        const float up_time = 1000;
+
+                        back.ScaleTo(target.Scale.X - scale_amount, down_time, Easing.OutQuint)
+                            .Then()
+                            .ScaleTo(1, up_time, Easing.OutQuint);
+
+                        target.Animate(
+                            t => t.ScaleTo(target.Scale.X - scale_amount, down_time, Easing.OutQuint),
+                            t => t.FadeTo(Math.Min(target.Alpha + alpha_amount, 1), down_time, Easing.OutQuint)
+                        ).Then(
+                            t => t.ScaleTo(1, up_time, Easing.OutQuint),
+                            t => t.FadeOut(up_time, Easing.OutQuint)
+                        );
+                    }
+
+                    return false;
+                }
+
+                public void OnReleased(KeyBindingReleaseEvent<TaikoAction> e)
+                {
+                }
             }
         }
     }

osu.Game.Rulesets.Taiko/UI/TaikoPlayfield.cs

@@ -7,6 +7,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using osu.Framework.Allocation;
+using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Pooling;
@@ -34,6 +35,11 @@ namespace osu.Game.Rulesets.Taiko.UI
         /// </summary>
         public const float DEFAULT_HEIGHT = 200;
 
+        /// <summary>
+        /// Whether the hit target should be nudged further towards the left area, matching the stable "classic" position.
+        /// </summary>
+        public Bindable<bool> ClassicHitTargetPosition = new BindableBool();
+
         private Container<HitExplosion> hitExplosionContainer;
         private Container<KiaiHitExplosion> kiaiExplosionContainer;
         private JudgementContainer<DrawableTaikoJudgement> judgementContainer;
@@ -45,8 +51,8 @@ namespace osu.Game.Rulesets.Taiko.UI
         private readonly IDictionary<HitResult, HitExplosionPool> explosionPools = new Dictionary<HitResult, HitExplosionPool>();
 
         private ProxyContainer topLevelHitContainer;
+        private InputDrum inputDrum;
         private Container rightArea;
-        private Container leftArea;
 
         /// <remarks>
         /// <see cref="Playfield.AddNested"/> is purposefully not called on this to prevent i.e. being able to interact
@@ -54,14 +60,43 @@ namespace osu.Game.Rulesets.Taiko.UI
         /// </remarks>
         private BarLinePlayfield barLinePlayfield;
 
-        private Container hitTargetOffsetContent;
+        private Container playfieldContent;
+        private Container playfieldOverlay;
 
         [BackgroundDependencyLoader]
         private void load(OsuColour colours)
         {
+            inputDrum = new InputDrum(HitObjectContainer)
+            {
+                Anchor = Anchor.CentreLeft,
+                Origin = Anchor.CentreLeft,
+                AutoSizeAxes = Axes.X,
+                RelativeSizeAxes = Axes.Y,
+            };
+
             InternalChildren = new[]
             {
                 new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.PlayfieldBackgroundRight), _ => new PlayfieldBackgroundRight()),
+                new Container
+                {
+                    Name = "Left overlay",
+                    RelativeSizeAxes = Axes.Both,
+                    FillMode = FillMode.Fit,
+                    BorderColour = colours.Gray0,
+                    Children = new[]
+                    {
+                        new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.PlayfieldBackgroundLeft), _ => new PlayfieldBackgroundLeft()),
+                        inputDrum.CreateProxy(),
+                    }
+                },
+                mascot = new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.Mascot), _ => Empty())
+                {
+                    Origin = Anchor.BottomLeft,
+                    Anchor = Anchor.TopLeft,
+                    RelativePositionAxes = Axes.Y,
+                    RelativeSizeAxes = Axes.None,
+                    Y = 0.2f
+                },
                 rightArea = new Container
                 {
                     Name = "Right area",
@@ -71,7 +106,7 @@ namespace osu.Game.Rulesets.Taiko.UI
                     {
                         new Container
                         {
-                            Name = "Masked elements before hit objects",
+                            Name = "Elements before hit objects",
                             RelativeSizeAxes = Axes.Both,
                             FillMode = FillMode.Fit,
                             Children = new[]
@@ -86,22 +121,28 @@ namespace osu.Game.Rulesets.Taiko.UI
                                 }
                             }
                         },
-                        hitTargetOffsetContent = new Container
+                        new Container
                         {
+                            Name = "Masked hit objects content",
+                            RelativeSizeAxes = Axes.Both,
+                            Masking = true,
+                            Child = playfieldContent = new Container
+                            {
+                                RelativeSizeAxes = Axes.Both,
+                                Children = new Drawable[]
+                                {
+                                    barLinePlayfield = new BarLinePlayfield(),
+                                    HitObjectContainer,
+                                }
+                            }
+                        },
+                        playfieldOverlay = new Container
+                        {
+                            Name = "Elements after hit objects",
                             RelativeSizeAxes = Axes.Both,
                             Children = new Drawable[]
                             {
-                                barLinePlayfield = new BarLinePlayfield(),
-                                new Container
-                                {
-                                    Name = "Hit objects",
-                                    RelativeSizeAxes = Axes.Both,
-                                    Children = new Drawable[]
-                                    {
-                                        HitObjectContainer,
-                                        drumRollHitContainer = new DrumRollHitContainer()
-                                    }
-                                },
+                                drumRollHitContainer = new DrumRollHitContainer(),
                                 kiaiExplosionContainer = new Container<KiaiHitExplosion>
                                 {
                                     Name = "Kiai hit explosions",
@@ -117,36 +158,15 @@ namespace osu.Game.Rulesets.Taiko.UI
                         },
                     }
                 },
-                leftArea = new Container
-                {
-                    Name = "Left overlay",
-                    RelativeSizeAxes = Axes.Both,
-                    FillMode = FillMode.Fit,
-                    BorderColour = colours.Gray0,
-                    Children = new Drawable[]
-                    {
-                        new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.PlayfieldBackgroundLeft), _ => new PlayfieldBackgroundLeft()),
-                        new InputDrum(HitObjectContainer)
-                        {
-                            Anchor = Anchor.CentreLeft,
-                            Origin = Anchor.CentreLeft,
-                        },
-                    }
-                },
-                mascot = new SkinnableDrawable(new TaikoSkinComponent(TaikoSkinComponents.Mascot), _ => Empty())
-                {
-                    Origin = Anchor.BottomLeft,
-                    Anchor = Anchor.TopLeft,
-                    RelativePositionAxes = Axes.Y,
-                    RelativeSizeAxes = Axes.None,
-                    Y = 0.2f
-                },
                 topLevelHitContainer = new ProxyContainer
                 {
                     Name = "Top level hit objects",
                     RelativeSizeAxes = Axes.Both,
                 },
                 drumRollHitContainer.CreateProxy(),
+                // this is added at the end of the hierarchy to receive input before taiko objects.
+                // but is proxied below everything to not cover visual effects such as hit explosions.
+                inputDrum,
             };
 
             RegisterPool<Hit, DrawableHit>(50);
@@ -193,8 +213,9 @@ namespace osu.Game.Rulesets.Taiko.UI
 
             // Padding is required to be updated for elements which are based on "absolute" X sized elements.
             // This is basically allowing for correct alignment as relative pieces move around them.
-            rightArea.Padding = new MarginPadding { Left = leftArea.DrawWidth };
-            hitTargetOffsetContent.Padding = new MarginPadding { Left = HitTarget.DrawWidth / 2 };
+            rightArea.Padding = new MarginPadding { Left = inputDrum.Width };
+            playfieldContent.Padding = new MarginPadding { Left = HitTarget.DrawWidth / 2 };
+            playfieldOverlay.Padding = new MarginPadding { Left = HitTarget.DrawWidth / 2 };
 
             mascot.Scale = new Vector2(DrawHeight / DEFAULT_HEIGHT);
         }

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/NonVisual/BeatmapSetInfoEqualityTest.cs

@@ -62,9 +62,45 @@ namespace osu.Game.Tests.NonVisual
             Assert.IsTrue(beatmapSetA.Beatmaps.Single().AudioEquals(beatmapSetB.Beatmaps.Single()));
         }
 
-        private static void addAudioFile(BeatmapSetInfo beatmapSetInfo, string hash = null)
+        [Test]
+        public void TestAudioEqualityBeatmapInfoSameHash()
         {
-            beatmapSetInfo.Files.Add(new RealmNamedFileUsage(new RealmFile { Hash = hash ?? Guid.NewGuid().ToString() }, "audio.mp3"));
+            var beatmapSet = TestResources.CreateTestBeatmapSetInfo(2);
+
+            addAudioFile(beatmapSet);
+
+            var beatmap1 = beatmapSet.Beatmaps.First();
+            var beatmap2 = beatmapSet.Beatmaps.Last();
+
+            Assert.AreNotEqual(beatmap1, beatmap2);
+            Assert.IsTrue(beatmap1.AudioEquals(beatmap2));
+        }
+
+        [Test]
+        public void TestAudioEqualityBeatmapInfoDifferentHash()
+        {
+            var beatmapSet = TestResources.CreateTestBeatmapSetInfo(2);
+
+            const string filename1 = "audio1.mp3";
+            const string filename2 = "audio2.mp3";
+
+            addAudioFile(beatmapSet, filename: filename1);
+            addAudioFile(beatmapSet, filename: filename2);
+
+            var beatmap1 = beatmapSet.Beatmaps.First();
+            var beatmap2 = beatmapSet.Beatmaps.Last();
+
+            Assert.AreNotEqual(beatmap1, beatmap2);
+
+            beatmap1.Metadata.AudioFile = filename1;
+            beatmap2.Metadata.AudioFile = filename2;
+
+            Assert.IsFalse(beatmap1.AudioEquals(beatmap2));
+        }
+
+        private static void addAudioFile(BeatmapSetInfo beatmapSetInfo, string hash = null, string filename = null)
+        {
+            beatmapSetInfo.Files.Add(new RealmNamedFileUsage(new RealmFile { Hash = hash ?? Guid.NewGuid().ToString() }, filename ?? "audio.mp3"));
         }
 
         [Test]

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/Resources/TestResources.cs

@@ -138,7 +138,7 @@ namespace osu.Game.Tests.Resources
                         BPM = bpm,
                         Hash = Guid.NewGuid().ToString().ComputeMD5Hash(),
                         Ruleset = rulesetInfo,
-                        Metadata = metadata,
+                        Metadata = metadata.DeepClone(),
                         Difficulty = new BeatmapDifficulty
                         {
                             OverallDifficulty = diff,

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/TestSceneChangelogOverlay.cs

@@ -108,6 +108,7 @@ namespace osu.Game.Tests.Visual.Online
                 Version = "2018.712.0",
                 DisplayVersion = "2018.712.0",
                 UpdateStream = streams[OsuGameBase.CLIENT_STREAM_NAME],
+                CreatedAt = new DateTime(2018, 7, 12),
                 ChangelogEntries = new List<APIChangelogEntry>
                 {
                     new APIChangelogEntry
@@ -171,6 +172,7 @@ namespace osu.Game.Tests.Visual.Online
             {
                 Version = "2019.920.0",
                 DisplayVersion = "2019.920.0",
+                CreatedAt = new DateTime(2019, 9, 20),
                 UpdateStream = new APIUpdateStream
                 {
                     Name = "Test",

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

@@ -55,7 +55,7 @@ namespace osu.Game.Tests.Visual.Online
                 Id = 3103765,
                 IsOnline = true,
                 Statistics = new UserStatistics { GlobalRank = 1111 },
-                Country = new Country { FlagName = "JP" },
+                CountryCode = CountryCode.JP,
                 CoverUrl = "https://osu.ppy.sh/images/headers/profile-covers/c6.jpg"
             },
             new APIUser
@@ -64,7 +64,7 @@ namespace osu.Game.Tests.Visual.Online
                 Id = 2,
                 IsOnline = false,
                 Statistics = new UserStatistics { GlobalRank = 2222 },
-                Country = new Country { FlagName = "AU" },
+                CountryCode = CountryCode.AU,
                 CoverUrl = "https://osu.ppy.sh/images/headers/profile-covers/c3.jpg",
                 IsSupporter = true,
                 SupportLevel = 3,
@@ -73,7 +73,7 @@ namespace osu.Game.Tests.Visual.Online
             {
                 Username = "Evast",
                 Id = 8195163,
-                Country = new Country { FlagName = "BY" },
+                CountryCode = CountryCode.BY,
                 CoverUrl = "https://assets.ppy.sh/user-profile-covers/8195163/4a8e2ad5a02a2642b631438cfa6c6bd7e2f9db289be881cb27df18331f64144c.jpeg",
                 IsOnline = false,
                 LastVisit = DateTimeOffset.Now

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

@@ -23,7 +23,7 @@ namespace osu.Game.Tests.Visual.Online
 
         public TestSceneRankingsCountryFilter()
         {
-            var countryBindable = new Bindable<Country>();
+            var countryBindable = new Bindable<CountryCode>();
 
             AddRange(new Drawable[]
             {
@@ -56,20 +56,12 @@ namespace osu.Game.Tests.Visual.Online
                 }
             });
 
-            var country = new Country
-            {
-                FlagName = "BY",
-                FullName = "Belarus"
-            };
-            var unknownCountry = new Country
-            {
-                FlagName = "CK",
-                FullName = "Cook Islands"
-            };
+            const CountryCode country = CountryCode.BY;
+            const CountryCode unknown_country = CountryCode.CK;
 
             AddStep("Set country", () => countryBindable.Value = country);
-            AddStep("Set null country", () => countryBindable.Value = null);
-            AddStep("Set country with no flag", () => countryBindable.Value = unknownCountry);
+            AddStep("Set default country", () => countryBindable.Value = default);
+            AddStep("Set country with no flag", () => countryBindable.Value = unknown_country);
         }
     }
 }

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

@@ -19,7 +19,7 @@ namespace osu.Game.Tests.Visual.Online
 
         public TestSceneRankingsHeader()
         {
-            var countryBindable = new Bindable<Country>();
+            var countryBindable = new Bindable<CountryCode>();
             var ruleset = new Bindable<RulesetInfo>();
             var scope = new Bindable<RankingsScope>();
 
@@ -30,21 +30,12 @@ namespace osu.Game.Tests.Visual.Online
                 Ruleset = { BindTarget = ruleset }
             });
 
-            var country = new Country
-            {
-                FlagName = "BY",
-                FullName = "Belarus"
-            };
-
-            var unknownCountry = new Country
-            {
-                FlagName = "CK",
-                FullName = "Cook Islands"
-            };
+            const CountryCode country = CountryCode.BY;
+            const CountryCode unknown_country = CountryCode.CK;
 
             AddStep("Set country", () => countryBindable.Value = country);
             AddStep("Set scope to Score", () => scope.Value = RankingsScope.Score);
-            AddStep("Set country with no flag", () => countryBindable.Value = unknownCountry);
+            AddStep("Set country with no flag", () => countryBindable.Value = unknown_country);
         }
     }
 }

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

@@ -21,7 +21,7 @@ namespace osu.Game.Tests.Visual.Online
 
         private TestRankingsOverlay rankingsOverlay;
 
-        private readonly Bindable<Country> countryBindable = new Bindable<Country>();
+        private readonly Bindable<CountryCode> countryBindable = new Bindable<CountryCode>();
         private readonly Bindable<RankingsScope> scope = new Bindable<RankingsScope>();
 
         [SetUp]
@@ -48,15 +48,15 @@ namespace osu.Game.Tests.Visual.Online
         public void TestFlagScopeDependency()
         {
             AddStep("Set scope to Score", () => scope.Value = RankingsScope.Score);
-            AddAssert("Check country is Null", () => countryBindable.Value == null);
-            AddStep("Set country", () => countryBindable.Value = us_country);
+            AddAssert("Check country is default", () => countryBindable.IsDefault);
+            AddStep("Set country", () => countryBindable.Value = CountryCode.US);
             AddAssert("Check scope is Performance", () => scope.Value == RankingsScope.Performance);
         }
 
         [Test]
         public void TestShowCountry()
         {
-            AddStep("Show US", () => rankingsOverlay.ShowCountry(us_country));
+            AddStep("Show US", () => rankingsOverlay.ShowCountry(CountryCode.US));
         }
 
         private void loadRankingsOverlay()
@@ -69,15 +69,9 @@ namespace osu.Game.Tests.Visual.Online
             };
         }
 
-        private static readonly Country us_country = new Country
-        {
-            FlagName = "US",
-            FullName = "United States"
-        };
-
         private class TestRankingsOverlay : RankingsOverlay
         {
-            public new Bindable<Country> Country => base.Country;
+            public new Bindable<CountryCode> Country => base.Country;
         }
     }
 }

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

@@ -57,8 +57,7 @@ namespace osu.Game.Tests.Visual.Online
             {
                 new CountryStatistics
                 {
-                    Country = new Country { FlagName = "US", FullName = "United States" },
-                    FlagName = "US",
+                    Code = CountryCode.US,
                     ActiveUsers = 2_972_623,
                     PlayCount = 3_086_515_743,
                     RankedScore = 449_407_643_332_546,
@@ -66,8 +65,7 @@ namespace osu.Game.Tests.Visual.Online
                 },
                 new CountryStatistics
                 {
-                    Country = new Country { FlagName = "RU", FullName = "Russian Federation" },
-                    FlagName = "RU",
+                    Code = CountryCode.RU,
                     ActiveUsers = 1_609_989,
                     PlayCount = 1_637_052_841,
                     RankedScore = 221_660_827_473_004,
@@ -86,7 +84,7 @@ namespace osu.Game.Tests.Visual.Online
                 User = new APIUser
                 {
                     Username = "first active user",
-                    Country = new Country { FlagName = "JP" },
+                    CountryCode = CountryCode.JP,
                     Active = true,
                 },
                 Accuracy = 0.9972,
@@ -106,7 +104,7 @@ namespace osu.Game.Tests.Visual.Online
                 User = new APIUser
                 {
                     Username = "inactive user",
-                    Country = new Country { FlagName = "AU" },
+                    CountryCode = CountryCode.AU,
                     Active = false,
                 },
                 Accuracy = 0.9831,
@@ -126,7 +124,7 @@ namespace osu.Game.Tests.Visual.Online
                 User = new APIUser
                 {
                     Username = "second active user",
-                    Country = new Country { FlagName = "PL" },
+                    CountryCode = CountryCode.PL,
                     Active = true,
                 },
                 Accuracy = 0.9584,

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

@@ -157,11 +157,7 @@ namespace osu.Game.Tests.Visual.Online
                         {
                             Id = 6602580,
                             Username = @"waaiiru",
-                            Country = new Country
-                            {
-                                FullName = @"Spain",
-                                FlagName = @"ES",
-                            },
+                            CountryCode = CountryCode.ES,
                         },
                         Mods = new[]
                         {
@@ -184,11 +180,7 @@ namespace osu.Game.Tests.Visual.Online
                         {
                             Id = 4608074,
                             Username = @"Skycries",
-                            Country = new Country
-                            {
-                                FullName = @"Brazil",
-                                FlagName = @"BR",
-                            },
+                            CountryCode = CountryCode.BR,
                         },
                         Mods = new[]
                         {
@@ -210,11 +202,7 @@ namespace osu.Game.Tests.Visual.Online
                         {
                             Id = 1014222,
                             Username = @"eLy",
-                            Country = new Country
-                            {
-                                FullName = @"Japan",
-                                FlagName = @"JP",
-                            },
+                            CountryCode = CountryCode.JP,
                         },
                         Mods = new[]
                         {
@@ -235,11 +223,7 @@ namespace osu.Game.Tests.Visual.Online
                         {
                             Id = 1541390,
                             Username = @"Toukai",
-                            Country = new Country
-                            {
-                                FullName = @"Canada",
-                                FlagName = @"CA",
-                            },
+                            CountryCode = CountryCode.CA,
                         },
                         Mods = new[]
                         {
@@ -259,11 +243,7 @@ namespace osu.Game.Tests.Visual.Online
                         {
                             Id = 7151382,
                             Username = @"Mayuri Hana",
-                            Country = new Country
-                            {
-                                FullName = @"Thailand",
-                                FlagName = @"TH",
-                            },
+                            CountryCode = CountryCode.TH,
                         },
                         Rank = ScoreRank.D,
                         PP = 160,
@@ -275,18 +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;
@@ -302,11 +289,7 @@ namespace osu.Game.Tests.Visual.Online
                 {
                     Id = 7151382,
                     Username = @"Mayuri Hana",
-                    Country = new Country
-                    {
-                        FullName = @"Thailand",
-                        FlagName = @"TH",
-                    },
+                    CountryCode = CountryCode.TH,
                 },
                 Rank = ScoreRank.D,
                 PP = 160,

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

@@ -60,7 +60,7 @@ namespace osu.Game.Tests.Visual.Online
                     {
                         Username = @"flyte",
                         Id = 3103765,
-                        Country = new Country { FlagName = @"JP" },
+                        CountryCode = CountryCode.JP,
                         CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c6.jpg",
                         Status = { Value = new UserStatusOnline() }
                     }) { Width = 300 },
@@ -68,7 +68,7 @@ namespace osu.Game.Tests.Visual.Online
                     {
                         Username = @"peppy",
                         Id = 2,
-                        Country = new Country { FlagName = @"AU" },
+                        CountryCode = CountryCode.AU,
                         CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c3.jpg",
                         IsSupporter = true,
                         SupportLevel = 3,
@@ -77,7 +77,7 @@ namespace osu.Game.Tests.Visual.Online
                     {
                         Username = @"Evast",
                         Id = 8195163,
-                        Country = new Country { FlagName = @"BY" },
+                        CountryCode = CountryCode.BY,
                         CoverUrl = @"https://assets.ppy.sh/user-profile-covers/8195163/4a8e2ad5a02a2642b631438cfa6c6bd7e2f9db289be881cb27df18331f64144c.jpeg",
                         IsOnline = false,
                         LastVisit = DateTimeOffset.Now

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

@@ -24,7 +24,7 @@ namespace osu.Game.Tests.Visual.Online
         {
             Username = @"Somebody",
             Id = 1,
-            Country = new Country { FullName = @"Alien" },
+            CountryCode = CountryCode.Unknown,
             CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c1.jpg",
             JoinDate = DateTimeOffset.Now.AddDays(-1),
             LastVisit = DateTimeOffset.Now,
@@ -82,7 +82,7 @@ namespace osu.Game.Tests.Visual.Online
                 Username = @"peppy",
                 Id = 2,
                 IsSupporter = true,
-                Country = new Country { FullName = @"Australia", FlagName = @"AU" },
+                CountryCode = CountryCode.AU,
                 CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c3.jpg"
             }));
 
@@ -90,7 +90,7 @@ namespace osu.Game.Tests.Visual.Online
             {
                 Username = @"flyte",
                 Id = 3103765,
-                Country = new Country { FullName = @"Japan", FlagName = @"JP" },
+                CountryCode = CountryCode.JP,
                 CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c6.jpg"
             }));
 
@@ -99,7 +99,7 @@ namespace osu.Game.Tests.Visual.Online
                 Username = @"BanchoBot",
                 Id = 3,
                 IsBot = true,
-                Country = new Country { FullName = @"Saint Helena", FlagName = @"SH" },
+                CountryCode = CountryCode.SH,
                 CoverUrl = @"https://osu.ppy.sh/images/headers/profile-covers/c4.jpg"
             }));
 

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

@@ -21,7 +21,7 @@ namespace osu.Game.Tests.Visual.Online
     {
         public TestSceneUserProfileScores()
         {
-            var firstScore = new APIScore
+            var firstScore = new SoloScoreInfo
             {
                 PP = 1047.21,
                 Rank = ScoreRank.SH,
@@ -34,7 +34,7 @@ namespace osu.Game.Tests.Visual.Online
                     },
                     DifficultyName = "Extreme"
                 },
-                Date = DateTimeOffset.Now,
+                EndedAt = DateTimeOffset.Now,
                 Mods = new[]
                 {
                     new APIMod { Acronym = new OsuModHidden().Acronym },
@@ -44,7 +44,7 @@ namespace osu.Game.Tests.Visual.Online
                 Accuracy = 0.9813
             };
 
-            var secondScore = new APIScore
+            var secondScore = new SoloScoreInfo
             {
                 PP = 134.32,
                 Rank = ScoreRank.A,
@@ -57,7 +57,7 @@ namespace osu.Game.Tests.Visual.Online
                     },
                     DifficultyName = "[4K] Regret"
                 },
-                Date = DateTimeOffset.Now,
+                EndedAt = DateTimeOffset.Now,
                 Mods = new[]
                 {
                     new APIMod { Acronym = new OsuModHardRock().Acronym },
@@ -66,7 +66,7 @@ namespace osu.Game.Tests.Visual.Online
                 Accuracy = 0.998546
             };
 
-            var thirdScore = new APIScore
+            var thirdScore = new SoloScoreInfo
             {
                 PP = 96.83,
                 Rank = ScoreRank.S,
@@ -79,11 +79,11 @@ namespace osu.Game.Tests.Visual.Online
                     },
                     DifficultyName = "Insane"
                 },
-                Date = DateTimeOffset.Now,
+                EndedAt = DateTimeOffset.Now,
                 Accuracy = 0.9726
             };
 
-            var noPPScore = new APIScore
+            var noPPScore = new SoloScoreInfo
             {
                 Rank = ScoreRank.B,
                 Beatmap = new APIBeatmap
@@ -95,7 +95,7 @@ namespace osu.Game.Tests.Visual.Online
                     },
                     DifficultyName = "[4K] Cataclysmic Hypernova"
                 },
-                Date = DateTimeOffset.Now,
+                EndedAt = DateTimeOffset.Now,
                 Accuracy = 0.55879
             };
 

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/TestSceneBeatmapLeaderboard.cs

@@ -140,11 +140,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                 {
                     Id = 6602580,
                     Username = @"waaiiru",
-                    Country = new Country
-                    {
-                        FullName = @"Spain",
-                        FlagName = @"ES",
-                    },
+                    CountryCode = CountryCode.ES,
                 },
             });
         }
@@ -164,12 +160,8 @@ namespace osu.Game.Tests.Visual.SongSelect
                 {
                     Id = 6602580,
                     Username = @"waaiiru",
-                    Country = new Country
-                    {
-                        FullName = @"Spain",
-                        FlagName = @"ES",
-                    },
-                },
+                    CountryCode = CountryCode.ES,
+                }
             });
         }
 
@@ -225,11 +217,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 6602580,
                         Username = @"waaiiru",
-                        Country = new Country
-                        {
-                            FullName = @"Spain",
-                            FlagName = @"ES",
-                        },
+                        CountryCode = CountryCode.ES,
                     },
                 },
                 new ScoreInfo
@@ -246,11 +234,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 4608074,
                         Username = @"Skycries",
-                        Country = new Country
-                        {
-                            FullName = @"Brazil",
-                            FlagName = @"BR",
-                        },
+                        CountryCode = CountryCode.BR,
                     },
                 },
                 new ScoreInfo
@@ -268,11 +252,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 1014222,
                         Username = @"eLy",
-                        Country = new Country
-                        {
-                            FullName = @"Japan",
-                            FlagName = @"JP",
-                        },
+                        CountryCode = CountryCode.JP,
                     },
                 },
                 new ScoreInfo
@@ -290,11 +270,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 1541390,
                         Username = @"Toukai",
-                        Country = new Country
-                        {
-                            FullName = @"Canada",
-                            FlagName = @"CA",
-                        },
+                        CountryCode = CountryCode.CA,
                     },
                 },
                 new ScoreInfo
@@ -312,11 +288,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 2243452,
                         Username = @"Satoruu",
-                        Country = new Country
-                        {
-                            FullName = @"Venezuela",
-                            FlagName = @"VE",
-                        },
+                        CountryCode = CountryCode.VE,
                     },
                 },
                 new ScoreInfo
@@ -334,11 +306,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 2705430,
                         Username = @"Mooha",
-                        Country = new Country
-                        {
-                            FullName = @"France",
-                            FlagName = @"FR",
-                        },
+                        CountryCode = CountryCode.FR,
                     },
                 },
                 new ScoreInfo
@@ -356,11 +324,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 7151382,
                         Username = @"Mayuri Hana",
-                        Country = new Country
-                        {
-                            FullName = @"Thailand",
-                            FlagName = @"TH",
-                        },
+                        CountryCode = CountryCode.TH,
                     },
                 },
                 new ScoreInfo
@@ -378,11 +342,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 2051389,
                         Username = @"FunOrange",
-                        Country = new Country
-                        {
-                            FullName = @"Canada",
-                            FlagName = @"CA",
-                        },
+                        CountryCode = CountryCode.CA,
                     },
                 },
                 new ScoreInfo
@@ -400,11 +360,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 6169483,
                         Username = @"-Hebel-",
-                        Country = new Country
-                        {
-                            FullName = @"Mexico",
-                            FlagName = @"MX",
-                        },
+                        CountryCode = CountryCode.MX,
                     },
                 },
                 new ScoreInfo
@@ -422,11 +378,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 6702666,
                         Username = @"prhtnsm",
-                        Country = new Country
-                        {
-                            FullName = @"Germany",
-                            FlagName = @"DE",
-                        },
+                        CountryCode = CountryCode.DE,
                     },
                 },
             };

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

@@ -0,0 +1,156 @@
+// 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("only one set visible", () => carousel.ChildrenOfType<DrawableCarouselBeatmapSet>().Count() == 1);
+            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("only one set visible", () => carousel.ChildrenOfType<DrawableCarouselBeatmapSet>().Count() == 1);
+            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/SongSelect/TestSceneUserTopScoreContainer.cs

@@ -69,11 +69,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 6602580,
                         Username = @"waaiiru",
-                        Country = new Country
-                        {
-                            FullName = @"Spain",
-                            FlagName = @"ES",
-                        },
+                        CountryCode = CountryCode.ES,
                     },
                 },
                 new ScoreInfo
@@ -88,11 +84,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 4608074,
                         Username = @"Skycries",
-                        Country = new Country
-                        {
-                            FullName = @"Brazil",
-                            FlagName = @"BR",
-                        },
+                        CountryCode = CountryCode.BR,
                     },
                 },
                 new ScoreInfo
@@ -107,11 +99,7 @@ namespace osu.Game.Tests.Visual.SongSelect
                     {
                         Id = 1541390,
                         Username = @"Toukai",
-                        Country = new Country
-                        {
-                            FullName = @"Canada",
-                            FlagName = @"CA",
-                        },
+                        CountryCode = CountryCode.CA,
                     },
                 }
             };

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.Tests/Visual/UserInterface/TestSceneFPSCounter.cs

@@ -0,0 +1,51 @@
+// 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 NUnit.Framework;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Testing;
+using osu.Game.Graphics.UserInterface;
+using osuTK;
+using osuTK.Graphics;
+
+namespace osu.Game.Tests.Visual.UserInterface
+{
+    public class TestSceneFPSCounter : OsuTestScene
+    {
+        [SetUpSteps]
+        public void SetUpSteps()
+        {
+            AddStep("create display", () =>
+            {
+                Children = new Drawable[]
+                {
+                    new Box
+                    {
+                        Colour = Color4.White,
+                        RelativeSizeAxes = Axes.Both,
+                    },
+                    new FillFlowContainer
+                    {
+                        Anchor = Anchor.Centre,
+                        Origin = Anchor.Centre,
+                        AutoSizeAxes = Axes.Both,
+                        Direction = FillDirection.Vertical,
+                        Children = new Drawable[]
+                        {
+                            new FPSCounter(),
+                            new FPSCounter { Scale = new Vector2(2) },
+                            new FPSCounter { Scale = new Vector2(4) },
+                        }
+                    },
+                };
+            });
+        }
+
+        [Test]
+        public void TestBasic()
+        {
+        }
+    }
+}

osu.Game.Tournament/CountryExtensions.cs

@@ -0,0 +1,770 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Game.Users;
+
+namespace osu.Game.Tournament
+{
+    public static class CountryExtensions
+    {
+        public static string GetAcronym(this CountryCode country)
+        {
+            switch (country)
+            {
+                case CountryCode.BD:
+                    return "BGD";
+
+                case CountryCode.BE:
+                    return "BEL";
+
+                case CountryCode.BF:
+                    return "BFA";
+
+                case CountryCode.BG:
+                    return "BGR";
+
+                case CountryCode.BA:
+                    return "BIH";
+
+                case CountryCode.BB:
+                    return "BRB";
+
+                case CountryCode.WF:
+                    return "WLF";
+
+                case CountryCode.BL:
+                    return "BLM";
+
+                case CountryCode.BM:
+                    return "BMU";
+
+                case CountryCode.BN:
+                    return "BRN";
+
+                case CountryCode.BO:
+                    return "BOL";
+
+                case CountryCode.BH:
+                    return "BHR";
+
+                case CountryCode.BI:
+                    return "BDI";
+
+                case CountryCode.BJ:
+                    return "BEN";
+
+                case CountryCode.BT:
+                    return "BTN";
+
+                case CountryCode.JM:
+                    return "JAM";
+
+                case CountryCode.BV:
+                    return "BVT";
+
+                case CountryCode.BW:
+                    return "BWA";
+
+                case CountryCode.WS:
+                    return "WSM";
+
+                case CountryCode.BQ:
+                    return "BES";
+
+                case CountryCode.BR:
+                    return "BRA";
+
+                case CountryCode.BS:
+                    return "BHS";
+
+                case CountryCode.JE:
+                    return "JEY";
+
+                case CountryCode.BY:
+                    return "BLR";
+
+                case CountryCode.BZ:
+                    return "BLZ";
+
+                case CountryCode.RU:
+                    return "RUS";
+
+                case CountryCode.RW:
+                    return "RWA";
+
+                case CountryCode.RS:
+                    return "SRB";
+
+                case CountryCode.TL:
+                    return "TLS";
+
+                case CountryCode.RE:
+                    return "REU";
+
+                case CountryCode.TM:
+                    return "TKM";
+
+                case CountryCode.TJ:
+                    return "TJK";
+
+                case CountryCode.RO:
+                    return "ROU";
+
+                case CountryCode.TK:
+                    return "TKL";
+
+                case CountryCode.GW:
+                    return "GNB";
+
+                case CountryCode.GU:
+                    return "GUM";
+
+                case CountryCode.GT:
+                    return "GTM";
+
+                case CountryCode.GS:
+                    return "SGS";
+
+                case CountryCode.GR:
+                    return "GRC";
+
+                case CountryCode.GQ:
+                    return "GNQ";
+
+                case CountryCode.GP:
+                    return "GLP";
+
+                case CountryCode.JP:
+                    return "JPN";
+
+                case CountryCode.GY:
+                    return "GUY";
+
+                case CountryCode.GG:
+                    return "GGY";
+
+                case CountryCode.GF:
+                    return "GUF";
+
+                case CountryCode.GE:
+                    return "GEO";
+
+                case CountryCode.GD:
+                    return "GRD";
+
+                case CountryCode.GB:
+                    return "GBR";
+
+                case CountryCode.GA:
+                    return "GAB";
+
+                case CountryCode.SV:
+                    return "SLV";
+
+                case CountryCode.GN:
+                    return "GIN";
+
+                case CountryCode.GM:
+                    return "GMB";
+
+                case CountryCode.GL:
+                    return "GRL";
+
+                case CountryCode.GI:
+                    return "GIB";
+
+                case CountryCode.GH:
+                    return "GHA";
+
+                case CountryCode.OM:
+                    return "OMN";
+
+                case CountryCode.TN:
+                    return "TUN";
+
+                case CountryCode.JO:
+                    return "JOR";
+
+                case CountryCode.HR:
+                    return "HRV";
+
+                case CountryCode.HT:
+                    return "HTI";
+
+                case CountryCode.HU:
+                    return "HUN";
+
+                case CountryCode.HK:
+                    return "HKG";
+
+                case CountryCode.HN:
+                    return "HND";
+
+                case CountryCode.HM:
+                    return "HMD";
+
+                case CountryCode.VE:
+                    return "VEN";
+
+                case CountryCode.PR:
+                    return "PRI";
+
+                case CountryCode.PS:
+                    return "PSE";
+
+                case CountryCode.PW:
+                    return "PLW";
+
+                case CountryCode.PT:
+                    return "PRT";
+
+                case CountryCode.SJ:
+                    return "SJM";
+
+                case CountryCode.PY:
+                    return "PRY";
+
+                case CountryCode.IQ:
+                    return "IRQ";
+
+                case CountryCode.PA:
+                    return "PAN";
+
+                case CountryCode.PF:
+                    return "PYF";
+
+                case CountryCode.PG:
+                    return "PNG";
+
+                case CountryCode.PE:
+                    return "PER";
+
+                case CountryCode.PK:
+                    return "PAK";
+
+                case CountryCode.PH:
+                    return "PHL";
+
+                case CountryCode.PN:
+                    return "PCN";
+
+                case CountryCode.PL:
+                    return "POL";
+
+                case CountryCode.PM:
+                    return "SPM";
+
+                case CountryCode.ZM:
+                    return "ZMB";
+
+                case CountryCode.EH:
+                    return "ESH";
+
+                case CountryCode.EE:
+                    return "EST";
+
+                case CountryCode.EG:
+                    return "EGY";
+
+                case CountryCode.ZA:
+                    return "ZAF";
+
+                case CountryCode.EC:
+                    return "ECU";
+
+                case CountryCode.IT:
+                    return "ITA";
+
+                case CountryCode.VN:
+                    return "VNM";
+
+                case CountryCode.SB:
+                    return "SLB";
+
+                case CountryCode.ET:
+                    return "ETH";
+
+                case CountryCode.SO:
+                    return "SOM";
+
+                case CountryCode.ZW:
+                    return "ZWE";
+
+                case CountryCode.SA:
+                    return "SAU";
+
+                case CountryCode.ES:
+                    return "ESP";
+
+                case CountryCode.ER:
+                    return "ERI";
+
+                case CountryCode.ME:
+                    return "MNE";
+
+                case CountryCode.MD:
+                    return "MDA";
+
+                case CountryCode.MG:
+                    return "MDG";
+
+                case CountryCode.MF:
+                    return "MAF";
+
+                case CountryCode.MA:
+                    return "MAR";
+
+                case CountryCode.MC:
+                    return "MCO";
+
+                case CountryCode.UZ:
+                    return "UZB";
+
+                case CountryCode.MM:
+                    return "MMR";
+
+                case CountryCode.ML:
+                    return "MLI";
+
+                case CountryCode.MO:
+                    return "MAC";
+
+                case CountryCode.MN:
+                    return "MNG";
+
+                case CountryCode.MH:
+                    return "MHL";
+
+                case CountryCode.MK:
+                    return "MKD";
+
+                case CountryCode.MU:
+                    return "MUS";
+
+                case CountryCode.MT:
+                    return "MLT";
+
+                case CountryCode.MW:
+                    return "MWI";
+
+                case CountryCode.MV:
+                    return "MDV";
+
+                case CountryCode.MQ:
+                    return "MTQ";
+
+                case CountryCode.MP:
+                    return "MNP";
+
+                case CountryCode.MS:
+                    return "MSR";
+
+                case CountryCode.MR:
+                    return "MRT";
+
+                case CountryCode.IM:
+                    return "IMN";
+
+                case CountryCode.UG:
+                    return "UGA";
+
+                case CountryCode.TZ:
+                    return "TZA";
+
+                case CountryCode.MY:
+                    return "MYS";
+
+                case CountryCode.MX:
+                    return "MEX";
+
+                case CountryCode.IL:
+                    return "ISR";
+
+                case CountryCode.FR:
+                    return "FRA";
+
+                case CountryCode.IO:
+                    return "IOT";
+
+                case CountryCode.SH:
+                    return "SHN";
+
+                case CountryCode.FI:
+                    return "FIN";
+
+                case CountryCode.FJ:
+                    return "FJI";
+
+                case CountryCode.FK:
+                    return "FLK";
+
+                case CountryCode.FM:
+                    return "FSM";
+
+                case CountryCode.FO:
+                    return "FRO";
+
+                case CountryCode.NI:
+                    return "NIC";
+
+                case CountryCode.NL:
+                    return "NLD";
+
+                case CountryCode.NO:
+                    return "NOR";
+
+                case CountryCode.NA:
+                    return "NAM";
+
+                case CountryCode.VU:
+                    return "VUT";
+
+                case CountryCode.NC:
+                    return "NCL";
+
+                case CountryCode.NE:
+                    return "NER";
+
+                case CountryCode.NF:
+                    return "NFK";
+
+                case CountryCode.NG:
+                    return "NGA";
+
+                case CountryCode.NZ:
+                    return "NZL";
+
+                case CountryCode.NP:
+                    return "NPL";
+
+                case CountryCode.NR:
+                    return "NRU";
+
+                case CountryCode.NU:
+                    return "NIU";
+
+                case CountryCode.CK:
+                    return "COK";
+
+                case CountryCode.XK:
+                    return "XKX";
+
+                case CountryCode.CI:
+                    return "CIV";
+
+                case CountryCode.CH:
+                    return "CHE";
+
+                case CountryCode.CO:
+                    return "COL";
+
+                case CountryCode.CN:
+                    return "CHN";
+
+                case CountryCode.CM:
+                    return "CMR";
+
+                case CountryCode.CL:
+                    return "CHL";
+
+                case CountryCode.CC:
+                    return "CCK";
+
+                case CountryCode.CA:
+                    return "CAN";
+
+                case CountryCode.CG:
+                    return "COG";
+
+                case CountryCode.CF:
+                    return "CAF";
+
+                case CountryCode.CD:
+                    return "COD";
+
+                case CountryCode.CZ:
+                    return "CZE";
+
+                case CountryCode.CY:
+                    return "CYP";
+
+                case CountryCode.CX:
+                    return "CXR";
+
+                case CountryCode.CR:
+                    return "CRI";
+
+                case CountryCode.CW:
+                    return "CUW";
+
+                case CountryCode.CV:
+                    return "CPV";
+
+                case CountryCode.CU:
+                    return "CUB";
+
+                case CountryCode.SZ:
+                    return "SWZ";
+
+                case CountryCode.SY:
+                    return "SYR";
+
+                case CountryCode.SX:
+                    return "SXM";
+
+                case CountryCode.KG:
+                    return "KGZ";
+
+                case CountryCode.KE:
+                    return "KEN";
+
+                case CountryCode.SS:
+                    return "SSD";
+
+                case CountryCode.SR:
+                    return "SUR";
+
+                case CountryCode.KI:
+                    return "KIR";
+
+                case CountryCode.KH:
+                    return "KHM";
+
+                case CountryCode.KN:
+                    return "KNA";
+
+                case CountryCode.KM:
+                    return "COM";
+
+                case CountryCode.ST:
+                    return "STP";
+
+                case CountryCode.SK:
+                    return "SVK";
+
+                case CountryCode.KR:
+                    return "KOR";
+
+                case CountryCode.SI:
+                    return "SVN";
+
+                case CountryCode.KP:
+                    return "PRK";
+
+                case CountryCode.KW:
+                    return "KWT";
+
+                case CountryCode.SN:
+                    return "SEN";
+
+                case CountryCode.SM:
+                    return "SMR";
+
+                case CountryCode.SL:
+                    return "SLE";
+
+                case CountryCode.SC:
+                    return "SYC";
+
+                case CountryCode.KZ:
+                    return "KAZ";
+
+                case CountryCode.KY:
+                    return "CYM";
+
+                case CountryCode.SG:
+                    return "SGP";
+
+                case CountryCode.SE:
+                    return "SWE";
+
+                case CountryCode.SD:
+                    return "SDN";
+
+                case CountryCode.DO:
+                    return "DOM";
+
+                case CountryCode.DM:
+                    return "DMA";
+
+                case CountryCode.DJ:
+                    return "DJI";
+
+                case CountryCode.DK:
+                    return "DNK";
+
+                case CountryCode.VG:
+                    return "VGB";
+
+                case CountryCode.DE:
+                    return "DEU";
+
+                case CountryCode.YE:
+                    return "YEM";
+
+                case CountryCode.DZ:
+                    return "DZA";
+
+                case CountryCode.US:
+                    return "USA";
+
+                case CountryCode.UY:
+                    return "URY";
+
+                case CountryCode.YT:
+                    return "MYT";
+
+                case CountryCode.UM:
+                    return "UMI";
+
+                case CountryCode.LB:
+                    return "LBN";
+
+                case CountryCode.LC:
+                    return "LCA";
+
+                case CountryCode.LA:
+                    return "LAO";
+
+                case CountryCode.TV:
+                    return "TUV";
+
+                case CountryCode.TW:
+                    return "TWN";
+
+                case CountryCode.TT:
+                    return "TTO";
+
+                case CountryCode.TR:
+                    return "TUR";
+
+                case CountryCode.LK:
+                    return "LKA";
+
+                case CountryCode.LI:
+                    return "LIE";
+
+                case CountryCode.LV:
+                    return "LVA";
+
+                case CountryCode.TO:
+                    return "TON";
+
+                case CountryCode.LT:
+                    return "LTU";
+
+                case CountryCode.LU:
+                    return "LUX";
+
+                case CountryCode.LR:
+                    return "LBR";
+
+                case CountryCode.LS:
+                    return "LSO";
+
+                case CountryCode.TH:
+                    return "THA";
+
+                case CountryCode.TF:
+                    return "ATF";
+
+                case CountryCode.TG:
+                    return "TGO";
+
+                case CountryCode.TD:
+                    return "TCD";
+
+                case CountryCode.TC:
+                    return "TCA";
+
+                case CountryCode.LY:
+                    return "LBY";
+
+                case CountryCode.VA:
+                    return "VAT";
+
+                case CountryCode.VC:
+                    return "VCT";
+
+                case CountryCode.AE:
+                    return "ARE";
+
+                case CountryCode.AD:
+                    return "AND";
+
+                case CountryCode.AG:
+                    return "ATG";
+
+                case CountryCode.AF:
+                    return "AFG";
+
+                case CountryCode.AI:
+                    return "AIA";
+
+                case CountryCode.VI:
+                    return "VIR";
+
+                case CountryCode.IS:
+                    return "ISL";
+
+                case CountryCode.IR:
+                    return "IRN";
+
+                case CountryCode.AM:
+                    return "ARM";
+
+                case CountryCode.AL:
+                    return "ALB";
+
+                case CountryCode.AO:
+                    return "AGO";
+
+                case CountryCode.AQ:
+                    return "ATA";
+
+                case CountryCode.AS:
+                    return "ASM";
+
+                case CountryCode.AR:
+                    return "ARG";
+
+                case CountryCode.AU:
+                    return "AUS";
+
+                case CountryCode.AT:
+                    return "AUT";
+
+                case CountryCode.AW:
+                    return "ABW";
+
+                case CountryCode.IN:
+                    return "IND";
+
+                case CountryCode.AX:
+                    return "ALA";
+
+                case CountryCode.AZ:
+                    return "AZE";
+
+                case CountryCode.IE:
+                    return "IRL";
+
+                case CountryCode.ID:
+                    return "IDN";
+
+                case CountryCode.UA:
+                    return "UKR";
+
+                case CountryCode.QA:
+                    return "QAT";
+
+                case CountryCode.MZ:
+                    return "MOZ";
+
+                default:
+                    throw new ArgumentOutOfRangeException(nameof(country));
+            }
+        }
+    }
+}

osu.Game.Tournament/Models/TournamentUser.cs

@@ -22,7 +22,8 @@ namespace osu.Game.Tournament.Models
         /// <summary>
         /// The player's country.
         /// </summary>
-        public Country? Country { get; set; }
+        [JsonProperty("country_code")]
+        public CountryCode CountryCode { get; set; }
 
         /// <summary>
         /// The player's global rank, or null if not available.
@@ -40,7 +41,7 @@ namespace osu.Game.Tournament.Models
             {
                 Id = OnlineID,
                 Username = Username,
-                Country = Country,
+                CountryCode = CountryCode,
                 CoverUrl = CoverUrl,
             };
 

osu.Game.Tournament/Screens/Editors/TeamEditorScreen.cs

@@ -3,13 +3,13 @@
 
 #nullable disable
 
+using System;
 using System.Collections.Generic;
 using System.Diagnostics;
-using System.IO;
 using System.Linq;
-using Newtonsoft.Json;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
+using osu.Framework.Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Shapes;
@@ -25,9 +25,6 @@ namespace osu.Game.Tournament.Screens.Editors
 {
     public class TeamEditorScreen : TournamentEditorScreen<TeamEditorScreen.TeamRow, TournamentTeam>
     {
-        [Resolved]
-        private TournamentGameBase game { get; set; }
-
         protected override BindableList<TournamentTeam> Storage => LadderInfo.Teams;
 
         [BackgroundDependencyLoader]
@@ -45,11 +42,17 @@ namespace osu.Game.Tournament.Screens.Editors
 
         private void addAllCountries()
         {
-            List<TournamentTeam> countries;
+            var countries = new List<TournamentTeam>();
 
-            using (Stream stream = game.Resources.GetStream("Resources/countries.json"))
-            using (var sr = new StreamReader(stream))
-                countries = JsonConvert.DeserializeObject<List<TournamentTeam>>(sr.ReadToEnd());
+            foreach (var country in Enum.GetValues(typeof(CountryCode)).Cast<CountryCode>().Skip(1))
+            {
+                countries.Add(new TournamentTeam
+                {
+                    FlagName = { Value = country.ToString() },
+                    FullName = { Value = country.GetDescription() },
+                    Acronym = { Value = country.GetAcronym() },
+                });
+            }
 
             Debug.Assert(countries != null);
 

osu.Game.Tournament/TournamentGameBase.cs

@@ -21,6 +21,7 @@ using osu.Game.Online.API.Requests.Responses;
 using osu.Game.Tournament.IO;
 using osu.Game.Tournament.IPC;
 using osu.Game.Tournament.Models;
+using osu.Game.Users;
 using osuTK.Input;
 
 namespace osu.Game.Tournament
@@ -186,7 +187,9 @@ namespace osu.Game.Tournament
         {
             var playersRequiringPopulation = ladder.Teams
                                                    .SelectMany(t => t.Players)
-                                                   .Where(p => string.IsNullOrEmpty(p.Username) || p.Rank == null).ToList();
+                                                   .Where(p => string.IsNullOrEmpty(p.Username)
+                                                               || p.CountryCode == CountryCode.Unknown
+                                                               || p.Rank == null).ToList();
 
             if (playersRequiringPopulation.Count == 0)
                 return false;
@@ -288,7 +291,7 @@ namespace osu.Game.Tournament
 
                 user.Username = res.Username;
                 user.CoverUrl = res.CoverUrl;
-                user.Country = res.Country;
+                user.CountryCode = res.CountryCode;
                 user.Rank = res.Statistics?.GlobalRank;
 
                 success?.Invoke();

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; }
 
@@ -169,8 +179,8 @@ namespace osu.Game.Beatmaps
             Debug.Assert(x.BeatmapSet != null);
             Debug.Assert(y.BeatmapSet != null);
 
-            string? fileHashX = x.BeatmapSet.Files.FirstOrDefault(f => f.Filename == getFilename(x.BeatmapSet.Metadata))?.File.Hash;
-            string? fileHashY = y.BeatmapSet.Files.FirstOrDefault(f => f.Filename == getFilename(y.BeatmapSet.Metadata))?.File.Hash;
+            string? fileHashX = x.BeatmapSet.Files.FirstOrDefault(f => f.Filename == getFilename(x.Metadata))?.File.Hash;
+            string? fileHashY = y.BeatmapSet.Files.FirstOrDefault(f => f.Filename == getFilename(y.Metadata))?.File.Hash;
 
             return fileHashX == fileHashY;
         }

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 +102,12 @@ namespace osu.Game.Beatmaps
 
                     beatmapInfo.BeatmapSet.Status = res.BeatmapSet?.Status ?? BeatmapOnlineStatus.None;
                     beatmapInfo.BeatmapSet.OnlineID = res.OnlineBeatmapSetID;
+                    beatmapInfo.BeatmapSet.DateRanked = res.BeatmapSet?.Ranked;
+                    beatmapInfo.BeatmapSet.DateSubmitted = res.BeatmapSet?.Submitted;
+
+                    beatmapInfo.OnlineMD5Hash = res.MD5Hash;
+                    beatmapInfo.LastOnlineUpdate = res.LastUpdated;
+
                     beatmapInfo.OnlineID = res.OnlineID;
 
                     beatmapInfo.Metadata.Author.OnlineID = res.AuthorID;
@@ -190,7 +196,8 @@ 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));
@@ -208,10 +215,13 @@ namespace osu.Game.Beatmaps
 
                                 beatmapInfo.BeatmapSet.Status = status;
                                 beatmapInfo.BeatmapSet.OnlineID = reader.GetInt32(0);
+                                // TODO: DateSubmitted and DateRanked are not provided by local cache.
                                 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

@@ -26,6 +26,16 @@ namespace osu.Game.Beatmaps
 
         public DateTimeOffset DateAdded { get; set; }
 
+        /// <summary>
+        /// The date this beatmap set was first submitted.
+        /// </summary>
+        public DateTimeOffset? DateSubmitted { get; set; }
+
+        /// <summary>
+        /// The date this beatmap set was ranked.
+        /// </summary>
+        public DateTimeOffset? DateRanked { get; set; }
+
         [JsonIgnore]
         public IBeatmapMetadataInfo Metadata => Beatmaps.FirstOrDefault()?.Metadata ?? new BeatmapMetadata();
 
@@ -93,5 +103,7 @@ 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/Beatmaps/WorkingBeatmapCache.cs

@@ -168,7 +168,7 @@ namespace osu.Game.Beatmaps
 
                     if (texture == null)
                     {
-                        Logger.Log($"Beatmap background failed to load (file {Metadata.BackgroundFile} not found on disk at expected location {fileStorePath}).", level: LogLevel.Error);
+                        Logger.Log($"Beatmap background failed to load (file {Metadata.BackgroundFile} not found on disk at expected location {fileStorePath}).");
                         return null;
                     }
 

osu.Game/Configuration/OsuConfigManager.cs

@@ -224,6 +224,12 @@ namespace osu.Game.Configuration
 
             return new TrackedSettings
             {
+                new TrackedSetting<bool>(OsuSetting.ShowFpsDisplay, state => new SettingDescription(
+                    rawValue: state,
+                    name: GlobalActionKeyBindingStrings.ToggleFPSCounter,
+                    value: state ? CommonStrings.Enabled.ToLower() : CommonStrings.Disabled.ToLower(),
+                    shortcut: LookupKeyBindings(GlobalAction.ToggleFPSDisplay))
+                ),
                 new TrackedSetting<bool>(OsuSetting.MouseDisableButtons, disabledState => new SettingDescription(
                     rawValue: !disabledState,
                     name: GlobalActionKeyBindingStrings.ToggleGameplayMouseButtons,

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

@@ -60,8 +60,11 @@ namespace osu.Game.Database
         /// 14   2022-03-01    Added BeatmapUserSettings to BeatmapInfo.
         /// 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.
+        /// 19   2022-07-19    Added DateSubmitted and DateRanked to BeatmapSetInfo.
         /// </summary>
-        private const int schema_version = 16;
+        private const int schema_version = 19;
 
         /// <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/Containers/BeatSyncedContainer.cs

@@ -28,7 +28,8 @@ namespace osu.Game.Graphics.Containers
     public class BeatSyncedContainer : Container
     {
         private int lastBeat;
-        private TimingControlPoint lastTimingPoint;
+        protected TimingControlPoint LastTimingPoint { get; private set; }
+        protected EffectControlPoint LastEffectPoint { get; private set; }
 
         /// <summary>
         /// The amount of time before a beat we should fire <see cref="OnNewBeat(int, TimingControlPoint, EffectControlPoint, ChannelAmplitudes)"/>.
@@ -127,7 +128,7 @@ namespace osu.Game.Graphics.Containers
 
             TimeSinceLastBeat = beatLength - TimeUntilNextBeat;
 
-            if (ReferenceEquals(timingPoint, lastTimingPoint) && beatIndex == lastBeat)
+            if (ReferenceEquals(timingPoint, LastTimingPoint) && beatIndex == lastBeat)
                 return;
 
             // as this event is sometimes used for sound triggers where `BeginDelayedSequence` has no effect, avoid firing it if too far away from the beat.
@@ -139,7 +140,8 @@ namespace osu.Game.Graphics.Containers
             }
 
             lastBeat = beatIndex;
-            lastTimingPoint = timingPoint;
+            LastTimingPoint = timingPoint;
+            LastEffectPoint = effectPoint;
         }
     }
 }

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/Graphics/UserInterface/FPSCounter.cs

@@ -0,0 +1,302 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Colour;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Cursor;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Input.Events;
+using osu.Framework.Localisation;
+using osu.Framework.Platform;
+using osu.Framework.Threading;
+using osu.Framework.Utils;
+using osu.Game.Configuration;
+using osu.Game.Graphics.Sprites;
+using osuTK;
+
+namespace osu.Game.Graphics.UserInterface
+{
+    public class FPSCounter : VisibilityContainer, IHasCustomTooltip
+    {
+        private RollingCounter<double> counterUpdateFrameTime = null!;
+        private RollingCounter<double> counterDrawFPS = null!;
+
+        private Container mainContent = null!;
+
+        private Container background = null!;
+
+        private Container counters = null!;
+
+        private const float idle_background_alpha = 0.4f;
+
+        private readonly BindableBool showFpsDisplay = new BindableBool(true);
+
+        [Resolved]
+        private OsuColour colours { get; set; } = null!;
+
+        public FPSCounter()
+        {
+            AutoSizeAxes = Axes.Both;
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuConfigManager config)
+        {
+            InternalChildren = new Drawable[]
+            {
+                mainContent = new Container
+                {
+                    Alpha = 0,
+                    Height = 26,
+                    Children = new Drawable[]
+                    {
+                        background = new Container
+                        {
+                            RelativeSizeAxes = Axes.Both,
+                            CornerRadius = 5,
+                            CornerExponent = 5f,
+                            Masking = true,
+                            Alpha = idle_background_alpha,
+                            Children = new Drawable[]
+                            {
+                                new Box
+                                {
+                                    Colour = colours.Gray0,
+                                    RelativeSizeAxes = Axes.Both,
+                                },
+                            }
+                        },
+                        counters = new Container
+                        {
+                            Anchor = Anchor.TopRight,
+                            Origin = Anchor.TopRight,
+                            AutoSizeAxes = Axes.Both,
+                            Children = new Drawable[]
+                            {
+                                counterUpdateFrameTime = new FrameTimeCounter
+                                {
+                                    Anchor = Anchor.TopRight,
+                                    Origin = Anchor.TopRight,
+                                    Margin = new MarginPadding(1),
+                                    Y = -2,
+                                },
+                                counterDrawFPS = new FramesPerSecondCounter
+                                {
+                                    Anchor = Anchor.TopRight,
+                                    Origin = Anchor.TopRight,
+                                    Margin = new MarginPadding(2),
+                                    Y = 10,
+                                    Scale = new Vector2(0.8f),
+                                }
+                            }
+                        },
+                    }
+                },
+            };
+
+            config.BindWith(OsuSetting.ShowFpsDisplay, showFpsDisplay);
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            displayTemporarily();
+
+            showFpsDisplay.BindValueChanged(showFps =>
+            {
+                State.Value = showFps.NewValue ? Visibility.Visible : Visibility.Hidden;
+                if (showFps.NewValue)
+                    displayTemporarily();
+            }, true);
+
+            State.BindValueChanged(state => showFpsDisplay.Value = state.NewValue == Visibility.Visible);
+        }
+
+        protected override void PopIn() => this.FadeIn(100);
+
+        protected override void PopOut() => this.FadeOut(100);
+
+        protected override bool OnHover(HoverEvent e)
+        {
+            background.FadeTo(1, 200);
+            displayTemporarily();
+            return base.OnHover(e);
+        }
+
+        protected override void OnHoverLost(HoverLostEvent e)
+        {
+            background.FadeTo(idle_background_alpha, 200);
+            displayTemporarily();
+            base.OnHoverLost(e);
+        }
+
+        private bool isDisplayed;
+
+        private ScheduledDelegate? fadeOutDelegate;
+
+        private double aimDrawFPS;
+        private double aimUpdateFPS;
+
+        private void displayTemporarily()
+        {
+            if (!isDisplayed)
+            {
+                mainContent.FadeTo(1, 300, Easing.OutQuint);
+                isDisplayed = true;
+            }
+
+            fadeOutDelegate?.Cancel();
+            fadeOutDelegate = null;
+
+            if (!IsHovered)
+            {
+                fadeOutDelegate = Scheduler.AddDelayed(() =>
+                {
+                    mainContent.FadeTo(0, 300, Easing.OutQuint);
+                    isDisplayed = false;
+                }, 2000);
+            }
+        }
+
+        [Resolved]
+        private GameHost gameHost { get; set; } = null!;
+
+        protected override void Update()
+        {
+            base.Update();
+
+            mainContent.Width = Math.Max(mainContent.Width, counters.DrawWidth);
+
+            // Handle the case where the window has become inactive or the user changed the
+            // frame limiter (we want to show the FPS as it's changing, even if it isn't an outlier).
+            bool aimRatesChanged = updateAimFPS();
+
+            // TODO: this is wrong (elapsed clock time, not actual run time).
+            double newUpdateFrameTime = gameHost.UpdateThread.Clock.ElapsedFrameTime;
+            double newDrawFrameTime = gameHost.DrawThread.Clock.ElapsedFrameTime;
+            double newDrawFps = gameHost.DrawThread.Clock.FramesPerSecond;
+
+            const double spike_time_ms = 20;
+
+            bool hasUpdateSpike = counterUpdateFrameTime.Current.Value < spike_time_ms && newUpdateFrameTime > spike_time_ms;
+            // use elapsed frame time rather then FramesPerSecond to better catch stutter frames.
+            bool hasDrawSpike = counterDrawFPS.Current.Value > (1000 / spike_time_ms) && newDrawFrameTime > spike_time_ms;
+
+            // If the frame time spikes up, make sure it shows immediately on the counter.
+            if (hasUpdateSpike)
+                counterUpdateFrameTime.SetCountWithoutRolling(newUpdateFrameTime);
+            else
+                counterUpdateFrameTime.Current.Value = newUpdateFrameTime;
+
+            if (hasDrawSpike)
+                // show spike time using raw elapsed value, to account for `FramesPerSecond` being so averaged spike frames don't show.
+                counterDrawFPS.SetCountWithoutRolling(1000 / newDrawFrameTime);
+            else
+                counterDrawFPS.Current.Value = newDrawFps;
+
+            counterDrawFPS.Colour = getColour(counterDrawFPS.DisplayedCount / aimDrawFPS);
+
+            double displayedUpdateFPS = 1000 / counterUpdateFrameTime.DisplayedCount;
+            counterUpdateFrameTime.Colour = getColour(displayedUpdateFPS / aimUpdateFPS);
+
+            bool hasSignificantChanges = aimRatesChanged
+                                         || hasDrawSpike
+                                         || hasUpdateSpike
+                                         || counterDrawFPS.DisplayedCount < aimDrawFPS * 0.8
+                                         || displayedUpdateFPS < aimUpdateFPS * 0.8;
+
+            if (hasSignificantChanges)
+                displayTemporarily();
+        }
+
+        private bool updateAimFPS()
+        {
+            if (gameHost.UpdateThread.Clock.Throttling)
+            {
+                double newAimDrawFPS = gameHost.DrawThread.Clock.MaximumUpdateHz;
+                double newAimUpdateFPS = gameHost.UpdateThread.Clock.MaximumUpdateHz;
+
+                if (aimDrawFPS != newAimDrawFPS || aimUpdateFPS != newAimUpdateFPS)
+                {
+                    aimDrawFPS = newAimDrawFPS;
+                    aimUpdateFPS = newAimUpdateFPS;
+                    return true;
+                }
+            }
+            else
+            {
+                double newAimFPS = gameHost.InputThread.Clock.MaximumUpdateHz;
+
+                if (aimDrawFPS != newAimFPS || aimUpdateFPS != newAimFPS)
+                {
+                    aimUpdateFPS = aimDrawFPS = newAimFPS;
+                    return true;
+                }
+            }
+
+            return false;
+        }
+
+        private ColourInfo getColour(double performanceRatio)
+        {
+            if (performanceRatio < 0.5f)
+                return Interpolation.ValueAt(performanceRatio, colours.Red, colours.Orange2, 0, 0.5);
+
+            return Interpolation.ValueAt(performanceRatio, colours.Orange2, colours.Lime0, 0.5, 0.9);
+        }
+
+        public ITooltip GetCustomTooltip() => new FPSCounterTooltip();
+
+        public object TooltipContent => this;
+
+        public class FramesPerSecondCounter : RollingCounter<double>
+        {
+            protected override double RollingDuration => 1000;
+
+            protected override OsuSpriteText CreateSpriteText()
+            {
+                return new OsuSpriteText
+                {
+                    Anchor = Anchor.TopRight,
+                    Origin = Anchor.TopRight,
+                    Font = OsuFont.Default.With(fixedWidth: true, size: 16, weight: FontWeight.SemiBold),
+                    Spacing = new Vector2(-2),
+                };
+            }
+
+            protected override LocalisableString FormatCount(double count)
+            {
+                return $"{count:#,0}fps";
+            }
+        }
+
+        public class FrameTimeCounter : RollingCounter<double>
+        {
+            protected override double RollingDuration => 1000;
+
+            protected override OsuSpriteText CreateSpriteText()
+            {
+                return new OsuSpriteText
+                {
+                    Anchor = Anchor.TopRight,
+                    Origin = Anchor.TopRight,
+                    Font = OsuFont.Default.With(fixedWidth: true, size: 16, weight: FontWeight.SemiBold),
+                    Spacing = new Vector2(-1),
+                };
+            }
+
+            protected override LocalisableString FormatCount(double count)
+            {
+                if (count < 1)
+                    return $"{count:N1}ms";
+
+                return $"{count:N0}ms";
+            }
+        }
+    }
+}

osu.Game/Graphics/UserInterface/FPSCounterTooltip.cs

@@ -0,0 +1,97 @@
+// 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.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Cursor;
+using osu.Framework.Graphics.Shapes;
+using osu.Framework.Platform;
+using osu.Game.Graphics.Containers;
+using osuTK;
+
+namespace osu.Game.Graphics.UserInterface
+{
+    public class FPSCounterTooltip : CompositeDrawable, ITooltip
+    {
+        private OsuTextFlowContainer textFlow = null!;
+
+        [Resolved]
+        private GameHost gameHost { get; set; } = null!;
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour colours)
+        {
+            AutoSizeAxes = Axes.Both;
+
+            CornerRadius = 15;
+            Masking = true;
+
+            InternalChildren = new Drawable[]
+            {
+                new Box
+                {
+                    Colour = colours.Gray1,
+                    Alpha = 1,
+                    RelativeSizeAxes = Axes.Both,
+                },
+                new OsuTextFlowContainer(cp =>
+                {
+                    cp.Font = OsuFont.Default.With(weight: FontWeight.SemiBold);
+                })
+                {
+                    AutoSizeAxes = Axes.Both,
+                    TextAnchor = Anchor.TopRight,
+                    Margin = new MarginPadding { Left = 5, Vertical = 10 },
+                    Text = string.Join('\n', gameHost.Threads.Select(t => t.Name))
+                },
+                textFlow = new OsuTextFlowContainer(cp =>
+                {
+                    cp.Font = OsuFont.Default.With(fixedWidth: true, weight: FontWeight.Regular);
+                    cp.Spacing = new Vector2(-1);
+                })
+                {
+                    Width = 190,
+                    Margin = new MarginPadding { Left = 35, Right = 10, Vertical = 10 },
+                    AutoSizeAxes = Axes.Y,
+                    TextAnchor = Anchor.TopRight,
+                },
+            };
+        }
+
+        private int lastUpdate;
+
+        protected override void Update()
+        {
+            int currentSecond = (int)(Clock.CurrentTime / 100);
+
+            if (currentSecond != lastUpdate)
+            {
+                lastUpdate = currentSecond;
+
+                textFlow.Clear();
+
+                foreach (var thread in gameHost.Threads)
+                {
+                    var clock = thread.Clock;
+
+                    string maximum = clock.Throttling
+                        ? $"/{(clock.MaximumUpdateHz > 0 && clock.MaximumUpdateHz < 10000 ? clock.MaximumUpdateHz.ToString("0") : "∞"),4}"
+                        : string.Empty;
+
+                    textFlow.AddParagraph($"{clock.FramesPerSecond:0}{maximum}fps ({clock.ElapsedFrameTime:0.00}ms)");
+                }
+            }
+        }
+
+        public void SetContent(object content)
+        {
+        }
+
+        public void Move(Vector2 pos)
+        {
+            Position = pos;
+        }
+    }
+}

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/Input/Bindings/GlobalActionContainer.cs

@@ -45,6 +45,7 @@ namespace osu.Game.Input.Bindings
             new KeyBinding(InputKey.F9, GlobalAction.ToggleSocial),
             new KeyBinding(InputKey.F10, GlobalAction.ToggleGameplayMouseButtons),
             new KeyBinding(InputKey.F12, GlobalAction.TakeScreenshot),
+            new KeyBinding(new[] { InputKey.Control, InputKey.Shift, InputKey.F }, GlobalAction.ToggleFPSDisplay),
 
             new KeyBinding(new[] { InputKey.Control, InputKey.Alt, InputKey.R }, GlobalAction.ResetInputSettings),
             new KeyBinding(new[] { InputKey.Control, InputKey.T }, GlobalAction.ToggleToolbar),
@@ -328,5 +329,8 @@ namespace osu.Game.Input.Bindings
 
         [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.EditorTapForBPM))]
         EditorTapForBPM,
+
+        [LocalisableDescription(typeof(GlobalActionKeyBindingStrings), nameof(GlobalActionKeyBindingStrings.ToggleFPSCounter))]
+        ToggleFPSDisplay,
     }
 }

osu.Game/Localisation/GlobalActionKeyBindingStrings.cs

@@ -274,6 +274,11 @@ namespace osu.Game.Localisation
         /// </summary>
         public static LocalisableString ToggleSkinEditor => new TranslatableString(getKey(@"toggle_skin_editor"), @"Toggle skin editor");
 
+        /// <summary>
+        /// "Toggle FPS counter"
+        /// </summary>
+        public static LocalisableString ToggleFPSCounter => new TranslatableString(getKey(@"toggle_fps_counter"), @"Toggle FPS counter");
+
         /// <summary>
         /// "Previous volume meter"
         /// </summary>

osu.Game/Localisation/Language.cs

@@ -2,9 +2,11 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System.ComponentModel;
+using JetBrains.Annotations;
 
 namespace osu.Game.Localisation
 {
+    [UsedImplicitly(ImplicitUseTargetFlags.WithMembers)]
     public enum Language
     {
         [Description(@"English")]

osu.Game/Localisation/ToastStrings.cs

@@ -34,6 +34,16 @@ namespace osu.Game.Localisation
         /// </summary>
         public static LocalisableString RestartTrack => new TranslatableString(getKey(@"restart_track"), @"Restart track");
 
+        /// <summary>
+        /// "Beatmap saved"
+        /// </summary>
+        public static LocalisableString BeatmapSaved => new TranslatableString(getKey(@"beatmap_saved"), @"Beatmap saved");
+
+        /// <summary>
+        /// "Skin saved"
+        /// </summary>
+        public static LocalisableString SkinSaved => new TranslatableString(getKey(@"skin_saved"), @"Skin saved");
+
         private static string getKey(string key) => $@"{prefix}:{key}";
     }
 }

osu.Game/Models/RealmUser.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.Game.Database;
 using osu.Game.Users;
@@ -17,6 +15,16 @@ namespace osu.Game.Models
 
         public string Username { get; set; } = string.Empty;
 
+        [Ignored]
+        public CountryCode CountryCode
+        {
+            get => Enum.TryParse(CountryString, out CountryCode country) ? country : CountryCode.Unknown;
+            set => CountryString = value.ToString();
+        }
+
+        [MapTo(nameof(CountryCode))]
+        public string CountryString { get; set; } = default(CountryCode).ToString();
+
         public bool IsBot => false;
 
         public bool Equals(RealmUser other)

osu.Game/Online/API/APIMod.cs

@@ -5,13 +5,14 @@
 
 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;
 
@@ -44,11 +45,11 @@ 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());
             }
         }
 
-        public Mod ToMod(Ruleset ruleset)
+        public Mod ToMod([NotNull] Ruleset ruleset)
         {
             Mod resultMod = ruleset.CreateModFromAcronym(Acronym);
 
@@ -62,10 +63,17 @@ 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;
 
-                    resultMod.CopyAdjustedSetting((IBindable)property.GetValue(resultMod), settingValue);
+                    try
+                    {
+                        resultMod.CopyAdjustedSetting((IBindable)property.GetValue(resultMod), settingValue);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.Log($"Failed to copy mod setting value '{settingValue ?? "null"}' to \"{property.Name}\": {ex.Message}");
+                    }
                 }
             }