Merge branch 'master' into fix-multiplayer-mod-propagation-race

osu.Android.props

@@ -51,7 +51,7 @@
     <Reference Include="Java.Interop" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.211.0" />
+    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.211.1" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.128.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.215.0" />
   </ItemGroup>
 </Project>

osu.Android/OsuGameActivity.cs

@@ -20,7 +20,7 @@ namespace osu.Android
     [Activity(Theme = "@android:style/Theme.NoTitleBar", MainLauncher = true, ScreenOrientation = ScreenOrientation.FullUser, SupportsPictureInPicture = false, ConfigurationChanges = ConfigChanges.Orientation | ConfigChanges.ScreenSize, HardwareAccelerated = false, LaunchMode = LaunchMode.SingleInstance)]
     [IntentFilter(new[] { Intent.ActionView }, Categories = new[] { Intent.CategoryDefault }, DataScheme = "content", DataPathPattern = ".*\\\\.osz", DataHost = "*", DataMimeType = "*/*")]
     [IntentFilter(new[] { Intent.ActionView }, Categories = new[] { Intent.CategoryDefault }, DataScheme = "content", DataPathPattern = ".*\\\\.osk", DataHost = "*", DataMimeType = "*/*")]
-    [IntentFilter(new[] { Intent.ActionSend, Intent.ActionSendMultiple }, Categories = new[] { Intent.CategoryDefault }, DataMimeTypes = new[] { "application/zip", "application/octet-stream" })]
+    [IntentFilter(new[] { Intent.ActionSend, Intent.ActionSendMultiple }, Categories = new[] { Intent.CategoryDefault }, DataMimeTypes = new[] { "application/zip", "application/octet-stream", "application/download", "application/x-zip", "application/x-zip-compressed" })]
     [IntentFilter(new[] { Intent.ActionView }, Categories = new[] { Intent.CategoryBrowsable, Intent.CategoryDefault }, DataSchemes = new[] { "osu", "osump" })]
     public class OsuGameActivity : AndroidGameActivity
     {

osu.Desktop/OsuGameDesktop.cs

@@ -18,6 +18,7 @@ using osu.Framework.Screens;
 using osu.Game.Screens.Menu;
 using osu.Game.Updater;
 using osu.Desktop.Windows;
+using osu.Game.IO;
 
 namespace osu.Desktop
 {
@@ -32,7 +33,7 @@ namespace osu.Desktop
             noVersionOverlay = args?.Any(a => a == "--no-version-overlay") ?? false;
         }
 
-        public override Storage GetStorageForStableInstall()
+        public override StableStorage GetStorageForStableInstall()
         {
             try
             {
@@ -40,7 +41,7 @@ namespace osu.Desktop
                 {
                     string stablePath = getStableInstallPath();
                     if (!string.IsNullOrEmpty(stablePath))
-                        return new DesktopStorage(stablePath, desktopHost);
+                        return new StableStorage(stablePath, desktopHost);
                 }
             }
             catch (Exception)

osu.Game.Benchmarks/osu.Game.Benchmarks.csproj

@@ -8,7 +8,7 @@
 
   <ItemGroup>
     <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
-    <PackageReference Include="nunit" Version="3.12.0" />
+    <PackageReference Include="nunit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
   </ItemGroup>
 

osu.Game.Rulesets.Catch.Tests/osu.Game.Rulesets.Catch.Tests.csproj

@@ -3,7 +3,7 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>

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

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Catch.Replays;
@@ -12,7 +13,7 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModAutoplay : ModAutoplay<CatchHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "osu!salad!" } },
             Replay = new CatchAutoGenerator(beatmap).Generate(),

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

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Catch.Replays;
@@ -12,7 +13,7 @@ namespace osu.Game.Rulesets.Catch.Mods
 {
     public class CatchModCinema : ModCinema<CatchHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "osu!salad!" } },
             Replay = new CatchAutoGenerator(beatmap).Generate(),

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

@@ -12,7 +12,7 @@ namespace osu.Game.Rulesets.Catch.Mods
     public class CatchModDifficultyAdjust : ModDifficultyAdjust
     {
         [SettingSource("Circle Size", "Override a beatmap's set CS.", FIRST_SETTING_ORDER - 1)]
-        public BindableNumber<float> CircleSize { get; } = new BindableFloat
+        public BindableNumber<float> CircleSize { get; } = new BindableFloatWithLimitExtension
         {
             Precision = 0.1f,
             MinValue = 1,
@@ -22,7 +22,7 @@ namespace osu.Game.Rulesets.Catch.Mods
         };
 
         [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1)]
-        public BindableNumber<float> ApproachRate { get; } = new BindableFloat
+        public BindableNumber<float> ApproachRate { get; } = new BindableFloatWithLimitExtension
         {
             Precision = 0.1f,
             MinValue = 1,
@@ -31,6 +31,14 @@ namespace osu.Game.Rulesets.Catch.Mods
             Value = 5,
         };
 
+        protected override void ApplyLimits(bool extended)
+        {
+            base.ApplyLimits(extended);
+
+            CircleSize.MaxValue = extended ? 11 : 10;
+            ApproachRate.MaxValue = extended ? 11 : 10;
+        }
+
         public override string SettingDescription
         {
             get

osu.Game.Rulesets.Mania.Tests/osu.Game.Rulesets.Mania.Tests.csproj

@@ -3,7 +3,7 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>

osu.Game.Rulesets.Mania/Mods/ManiaModAutoplay.cs

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mania.Beatmaps;
 using osu.Game.Rulesets.Mania.Objects;
@@ -13,7 +14,7 @@ namespace osu.Game.Rulesets.Mania.Mods
 {
     public class ManiaModAutoplay : ModAutoplay<ManiaHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "osu!topus!" } },
             Replay = new ManiaAutoGenerator((ManiaBeatmap)beatmap).Generate(),

osu.Game.Rulesets.Mania/Mods/ManiaModCinema.cs

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mania.Beatmaps;
 using osu.Game.Rulesets.Mania.Objects;
@@ -13,7 +14,7 @@ namespace osu.Game.Rulesets.Mania.Mods
 {
     public class ManiaModCinema : ModCinema<ManiaHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "osu!topus!" } },
             Replay = new ManiaAutoGenerator((ManiaBeatmap)beatmap).Generate(),

osu.Game.Rulesets.Mania/Skinning/Legacy/ManiaLegacySkinTransformer.cs

@@ -140,11 +140,11 @@ namespace osu.Game.Rulesets.Mania.Skinning.Legacy
             return animation == null ? null : new LegacyManiaJudgementPiece(result, animation);
         }
 
-        public override SampleChannel GetSample(ISampleInfo sampleInfo)
+        public override Sample GetSample(ISampleInfo sampleInfo)
         {
             // layered hit sounds never play in mania
             if (sampleInfo is ConvertHitObjectParser.LegacyHitSampleInfo legacySample && legacySample.IsLayered)
-                return new SampleChannelVirtual();
+                return new SampleVirtual();
 
             return Source.GetSample(sampleInfo);
         }

osu.Game.Rulesets.Osu.Tests/Mods/TestSceneOsuModAutoplay.cs

@@ -0,0 +1,65 @@
+// 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 NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Framework.Utils;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Osu.Mods;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.Skinning.Default;
+using osu.Game.Rulesets.Osu.UI;
+
+namespace osu.Game.Rulesets.Osu.Tests.Mods
+{
+    public class TestSceneOsuModAutoplay : OsuModTestScene
+    {
+        [Test]
+        public void TestSpmUnaffectedByRateAdjust()
+            => runSpmTest(new OsuModDaycore
+            {
+                SpeedChange = { Value = 0.88 }
+            });
+
+        [Test]
+        public void TestSpmUnaffectedByTimeRamp()
+            => runSpmTest(new ModWindUp
+            {
+                InitialRate = { Value = 0.7 },
+                FinalRate = { Value = 1.3 }
+            });
+
+        private void runSpmTest(Mod mod)
+        {
+            SpinnerSpmCounter spmCounter = null;
+
+            CreateModTest(new ModTestData
+            {
+                Autoplay = true,
+                Mod = mod,
+                Beatmap = new Beatmap
+                {
+                    HitObjects =
+                    {
+                        new Spinner
+                        {
+                            Duration = 2000,
+                            Position = OsuPlayfield.BASE_SIZE / 2
+                        }
+                    }
+                },
+                PassCondition = () => Player.ScoreProcessor.JudgedHits >= 1
+            });
+
+            AddUntilStep("fetch SPM counter", () =>
+            {
+                spmCounter = this.ChildrenOfType<SpinnerSpmCounter>().SingleOrDefault();
+                return spmCounter != null;
+            });
+
+            AddUntilStep("SPM is correct", () => Precision.AlmostEquals(spmCounter.SpinsPerMinute, 477, 5));
+        }
+    }
+}

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

@@ -98,7 +98,7 @@ namespace osu.Game.Rulesets.Osu.Tests
                 return null;
             }
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => throw new NotImplementedException();
 

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

@@ -1,9 +1,11 @@
 // 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.Collections.Generic;
 using NUnit.Framework;
 using osu.Game.Beatmaps;
 using osu.Game.Replays;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.Beatmaps;
 using osu.Game.Rulesets.Osu.Mods;
 using osu.Game.Rulesets.Osu.Objects;
@@ -65,10 +67,10 @@ namespace osu.Game.Rulesets.Osu.Tests
 
         private class TestAutoMod : OsuModAutoplay
         {
-            public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+            public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
             {
                 ScoreInfo = new ScoreInfo { User = new User { Username = "Autoplay" } },
-                Replay = new MissingAutoGenerator(beatmap).Generate()
+                Replay = new MissingAutoGenerator(beatmap, mods).Generate()
             };
         }
 
@@ -76,8 +78,8 @@ namespace osu.Game.Rulesets.Osu.Tests
         {
             public new OsuBeatmap Beatmap => (OsuBeatmap)base.Beatmap;
 
-            public MissingAutoGenerator(IBeatmap beatmap)
+            public MissingAutoGenerator(IBeatmap beatmap, IReadOnlyList<Mod> mods)
-                : base(beatmap)
+                : base(beatmap, mods)
             {
             }
 

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

@@ -0,0 +1,491 @@
+// 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.Extensions.TypeExtensions;
+using osu.Framework.Screens;
+using osu.Framework.Utils;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Replays;
+using osu.Game.Rulesets.Judgements;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Rulesets.Osu.Mods;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.Replays;
+using osu.Game.Rulesets.Replays;
+using osu.Game.Rulesets.Scoring;
+using osu.Game.Scoring;
+using osu.Game.Screens.Play;
+using osu.Game.Tests.Visual;
+using osuTK;
+
+namespace osu.Game.Rulesets.Osu.Tests
+{
+    public class TestSceneObjectOrderedHitPolicy : RateAdjustedBeatmapTestScene
+    {
+        private const double early_miss_window = 1000; // time after -1000 to -500 is considered a miss
+        private const double late_miss_window = 500; // time after +500 is considered a miss
+
+        /// <summary>
+        /// Tests clicking a future circle before the first circle's start time, while the first circle HAS NOT been judged.
+        /// </summary>
+        [Test]
+        public void TestClickSecondCircleBeforeFirstCircleTime()
+        {
+            const double time_first_circle = 1500;
+            const double time_second_circle = 1600;
+            Vector2 positionFirstCircle = Vector2.Zero;
+            Vector2 positionSecondCircle = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_first_circle,
+                    Position = positionFirstCircle
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_second_circle,
+                    Position = positionSecondCircle
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_first_circle - 100, Position = positionSecondCircle, Actions = { OsuAction.LeftButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Miss);
+            addJudgementAssert(hitObjects[1], HitResult.Miss);
+            addJudgementOffsetAssert(hitObjects[0], late_miss_window);
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle at the first circle's start time, while the first circle HAS NOT been judged.
+        /// </summary>
+        [Test]
+        public void TestClickSecondCircleAtFirstCircleTime()
+        {
+            const double time_first_circle = 1500;
+            const double time_second_circle = 1600;
+            Vector2 positionFirstCircle = Vector2.Zero;
+            Vector2 positionSecondCircle = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_first_circle,
+                    Position = positionFirstCircle
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_second_circle,
+                    Position = positionSecondCircle
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_first_circle, Position = positionSecondCircle, Actions = { OsuAction.LeftButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Miss);
+            addJudgementAssert(hitObjects[1], HitResult.Miss);
+            addJudgementOffsetAssert(hitObjects[0], late_miss_window);
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle after the first circle's start time, while the first circle HAS NOT been judged.
+        /// </summary>
+        [Test]
+        public void TestClickSecondCircleAfterFirstCircleTime()
+        {
+            const double time_first_circle = 1500;
+            const double time_second_circle = 1600;
+            Vector2 positionFirstCircle = Vector2.Zero;
+            Vector2 positionSecondCircle = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_first_circle,
+                    Position = positionFirstCircle
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_second_circle,
+                    Position = positionSecondCircle
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_first_circle + 100, Position = positionSecondCircle, Actions = { OsuAction.LeftButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Miss);
+            addJudgementAssert(hitObjects[1], HitResult.Miss);
+            addJudgementOffsetAssert(hitObjects[0], late_miss_window);
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle before the first circle's start time, while the first circle HAS been judged.
+        /// </summary>
+        [Test]
+        public void TestClickSecondCircleBeforeFirstCircleTimeWithFirstCircleJudged()
+        {
+            const double time_first_circle = 1500;
+            const double time_second_circle = 1600;
+            Vector2 positionFirstCircle = Vector2.Zero;
+            Vector2 positionSecondCircle = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_first_circle,
+                    Position = positionFirstCircle
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_second_circle,
+                    Position = positionSecondCircle
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_first_circle - 200, Position = positionFirstCircle, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_first_circle - 100, Position = positionSecondCircle, Actions = { OsuAction.RightButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Great);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+            addJudgementOffsetAssert(hitObjects[0], -200); // time_first_circle - 200
+            addJudgementOffsetAssert(hitObjects[0], -200); // time_second_circle - first_circle_time - 100
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle after the first circle's start time, while the first circle HAS been judged.
+        /// </summary>
+        [Test]
+        public void TestClickSecondCircleAfterFirstCircleTimeWithFirstCircleJudged()
+        {
+            const double time_first_circle = 1500;
+            const double time_second_circle = 1600;
+            Vector2 positionFirstCircle = Vector2.Zero;
+            Vector2 positionSecondCircle = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_first_circle,
+                    Position = positionFirstCircle
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_second_circle,
+                    Position = positionSecondCircle
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_first_circle - 200, Position = positionFirstCircle, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_first_circle, Position = positionSecondCircle, Actions = { OsuAction.RightButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Great);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+            addJudgementOffsetAssert(hitObjects[0], -200); // time_first_circle - 200
+            addJudgementOffsetAssert(hitObjects[1], -100); // time_second_circle - first_circle_time
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle after a slider's start time, but hitting all slider ticks.
+        /// </summary>
+        [Test]
+        public void TestMissSliderHeadAndHitAllSliderTicks()
+        {
+            const double time_slider = 1500;
+            const double time_circle = 1510;
+            Vector2 positionCircle = Vector2.Zero;
+            Vector2 positionSlider = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_circle,
+                    Position = positionCircle
+                },
+                new TestSlider
+                {
+                    StartTime = time_slider,
+                    Position = positionSlider,
+                    Path = new SliderPath(PathType.Linear, new[]
+                    {
+                        Vector2.Zero,
+                        new Vector2(25, 0),
+                    })
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_slider, Position = positionCircle, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_slider + 10, Position = positionSlider, Actions = { OsuAction.RightButton } }
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Miss);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+            addJudgementAssert("slider head", () => ((Slider)hitObjects[1]).HeadCircle, HitResult.LargeTickHit);
+            addJudgementAssert("slider tick", () => ((Slider)hitObjects[1]).NestedHitObjects[1] as SliderTick, HitResult.LargeTickHit);
+        }
+
+        /// <summary>
+        /// Tests clicking hitting future slider ticks before a circle.
+        /// </summary>
+        [Test]
+        public void TestHitSliderTicksBeforeCircle()
+        {
+            const double time_slider = 1500;
+            const double time_circle = 1510;
+            Vector2 positionCircle = Vector2.Zero;
+            Vector2 positionSlider = new Vector2(30);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_circle,
+                    Position = positionCircle
+                },
+                new TestSlider
+                {
+                    StartTime = time_slider,
+                    Position = positionSlider,
+                    Path = new SliderPath(PathType.Linear, new[]
+                    {
+                        Vector2.Zero,
+                        new Vector2(25, 0),
+                    })
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_slider, Position = positionSlider, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_circle + late_miss_window - 100, Position = positionCircle, Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_circle + late_miss_window - 90, Position = positionSlider, Actions = { OsuAction.LeftButton } },
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Great);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+            addJudgementAssert("slider head", () => ((Slider)hitObjects[1]).HeadCircle, HitResult.LargeTickHit);
+            addJudgementAssert("slider tick", () => ((Slider)hitObjects[1]).NestedHitObjects[1] as SliderTick, HitResult.LargeTickHit);
+        }
+
+        /// <summary>
+        /// Tests clicking a future circle before a spinner.
+        /// </summary>
+        [Test]
+        public void TestHitCircleBeforeSpinner()
+        {
+            const double time_spinner = 1500;
+            const double time_circle = 1800;
+            Vector2 positionCircle = Vector2.Zero;
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestSpinner
+                {
+                    StartTime = time_spinner,
+                    Position = new Vector2(256, 192),
+                    EndTime = time_spinner + 1000,
+                },
+                new TestHitCircle
+                {
+                    StartTime = time_circle,
+                    Position = positionCircle
+                },
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_spinner - 100, Position = positionCircle, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_spinner + 10, Position = new Vector2(236, 192), Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_spinner + 20, Position = new Vector2(256, 172), Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_spinner + 30, Position = new Vector2(276, 192), Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_spinner + 40, Position = new Vector2(256, 212), Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_spinner + 50, Position = new Vector2(236, 192), Actions = { OsuAction.RightButton } },
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Great);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+        }
+
+        [Test]
+        public void TestHitSliderHeadBeforeHitCircle()
+        {
+            const double time_circle = 1000;
+            const double time_slider = 1200;
+            Vector2 positionCircle = Vector2.Zero;
+            Vector2 positionSlider = new Vector2(80);
+
+            var hitObjects = new List<OsuHitObject>
+            {
+                new TestHitCircle
+                {
+                    StartTime = time_circle,
+                    Position = positionCircle
+                },
+                new TestSlider
+                {
+                    StartTime = time_slider,
+                    Position = positionSlider,
+                    Path = new SliderPath(PathType.Linear, new[]
+                    {
+                        Vector2.Zero,
+                        new Vector2(25, 0),
+                    })
+                }
+            };
+
+            performTest(hitObjects, new List<ReplayFrame>
+            {
+                new OsuReplayFrame { Time = time_circle - 100, Position = positionSlider, Actions = { OsuAction.LeftButton } },
+                new OsuReplayFrame { Time = time_circle, Position = positionCircle, Actions = { OsuAction.RightButton } },
+                new OsuReplayFrame { Time = time_slider, Position = positionSlider, Actions = { OsuAction.LeftButton } },
+            });
+
+            addJudgementAssert(hitObjects[0], HitResult.Great);
+            addJudgementAssert(hitObjects[1], HitResult.Great);
+        }
+
+        private void addJudgementAssert(OsuHitObject hitObject, HitResult result)
+        {
+            AddAssert($"({hitObject.GetType().ReadableName()} @ {hitObject.StartTime}) judgement is {result}",
+                () => judgementResults.Single(r => r.HitObject == hitObject).Type == result);
+        }
+
+        private void addJudgementAssert(string name, Func<OsuHitObject> hitObject, HitResult result)
+        {
+            AddAssert($"{name} judgement is {result}",
+                () => judgementResults.Single(r => r.HitObject == hitObject()).Type == result);
+        }
+
+        private void addJudgementOffsetAssert(OsuHitObject hitObject, double offset)
+        {
+            AddAssert($"({hitObject.GetType().ReadableName()} @ {hitObject.StartTime}) judged at {offset}",
+                () => Precision.AlmostEquals(judgementResults.Single(r => r.HitObject == hitObject).TimeOffset, offset, 100));
+        }
+
+        private ScoreAccessibleReplayPlayer currentPlayer;
+        private List<JudgementResult> judgementResults;
+
+        private void performTest(List<OsuHitObject> hitObjects, List<ReplayFrame> frames)
+        {
+            AddStep("load player", () =>
+            {
+                Beatmap.Value = CreateWorkingBeatmap(new Beatmap<OsuHitObject>
+                {
+                    HitObjects = hitObjects,
+                    BeatmapInfo =
+                    {
+                        BaseDifficulty = new BeatmapDifficulty { SliderTickRate = 3 },
+                        Ruleset = new OsuRuleset().RulesetInfo
+                    },
+                });
+
+                Beatmap.Value.Beatmap.ControlPointInfo.Add(0, new DifficultyControlPoint { SpeedMultiplier = 0.1f });
+
+                SelectedMods.Value = new[] { new OsuModClassic() };
+
+                var p = new ScoreAccessibleReplayPlayer(new Score { Replay = new Replay { Frames = frames } });
+
+                p.OnLoadComplete += _ =>
+                {
+                    p.ScoreProcessor.NewJudgement += result =>
+                    {
+                        if (currentPlayer == p) judgementResults.Add(result);
+                    };
+                };
+
+                LoadScreen(currentPlayer = p);
+                judgementResults = new List<JudgementResult>();
+            });
+
+            AddUntilStep("Beatmap at 0", () => Beatmap.Value.Track.CurrentTime == 0);
+            AddUntilStep("Wait until player is loaded", () => currentPlayer.IsCurrentScreen());
+            AddUntilStep("Wait for completion", () => currentPlayer.ScoreProcessor.HasCompleted.Value);
+        }
+
+        private class TestHitCircle : HitCircle
+        {
+            protected override HitWindows CreateHitWindows() => new TestHitWindows();
+        }
+
+        private class TestSlider : Slider
+        {
+            public TestSlider()
+            {
+                DefaultsApplied += _ =>
+                {
+                    HeadCircle.HitWindows = new TestHitWindows();
+                    TailCircle.HitWindows = new TestHitWindows();
+
+                    HeadCircle.HitWindows.SetDifficulty(0);
+                    TailCircle.HitWindows.SetDifficulty(0);
+                };
+            }
+        }
+
+        private class TestSpinner : Spinner
+        {
+            protected override void ApplyDefaultsToSelf(ControlPointInfo controlPointInfo, BeatmapDifficulty difficulty)
+            {
+                base.ApplyDefaultsToSelf(controlPointInfo, difficulty);
+                SpinsRequired = 1;
+            }
+        }
+
+        private class TestHitWindows : HitWindows
+        {
+            private static readonly DifficultyRange[] ranges =
+            {
+                new DifficultyRange(HitResult.Great, 500, 500, 500),
+                new DifficultyRange(HitResult.Miss, early_miss_window, early_miss_window, early_miss_window),
+            };
+
+            public override bool IsHitResultAllowed(HitResult result) => result == HitResult.Great || result == HitResult.Miss;
+
+            protected override DifficultyRange[] GetRanges() => ranges;
+        }
+
+        private class ScoreAccessibleReplayPlayer : ReplayPlayer
+        {
+            public new ScoreProcessor ScoreProcessor => base.ScoreProcessor;
+
+            protected override bool PauseOnFocusLost => false;
+
+            public ScoreAccessibleReplayPlayer(Score score)
+                : base(score, new PlayerConfiguration
+                {
+                    AllowPause = false,
+                    ShowResults = false,
+                })
+            {
+            }
+        }
+    }
+}

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

@@ -162,7 +162,7 @@ namespace osu.Game.Rulesets.Osu.Tests
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => null;
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => null;
+            public Sample GetSample(ISampleInfo sampleInfo) => null;
 
             public TValue GetValue<TConfiguration, TValue>(Func<TConfiguration, TValue> query) where TConfiguration : SkinConfiguration => default;
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => null;

osu.Game.Rulesets.Osu.Tests/osu.Game.Rulesets.Osu.Tests.csproj

@@ -3,7 +3,7 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>

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

@@ -27,7 +27,7 @@ namespace osu.Game.Rulesets.Osu.Edit.Blueprints.Sliders
         {
             base.Update();
 
-            CirclePiece.UpdateFrom(position == SliderPosition.Start ? HitObject.HeadCircle : HitObject.TailCircle);
+            CirclePiece.UpdateFrom(position == SliderPosition.Start ? (HitCircle)HitObject.HeadCircle : HitObject.TailCircle);
         }
 
         // Todo: This is temporary, since the slider circle masks don't do anything special yet. In the future they will handle input.

osu.Game.Rulesets.Osu/Judgements/SliderTickJudgement.cs

@@ -0,0 +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 osu.Game.Rulesets.Scoring;
+
+namespace osu.Game.Rulesets.Osu.Judgements
+{
+    public class SliderTickJudgement : OsuJudgement
+    {
+        public override HitResult MaxResult => HitResult.LargeTickHit;
+    }
+}

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

@@ -62,7 +62,7 @@ namespace osu.Game.Rulesets.Osu.Mods
             inputManager.AllowUserCursorMovement = false;
 
             // Generate the replay frames the cursor should follow
-            replayFrames = new OsuAutoGenerator(drawableRuleset.Beatmap).Generate().Frames.Cast<OsuReplayFrame>().ToList();
+            replayFrames = new OsuAutoGenerator(drawableRuleset.Beatmap, drawableRuleset.Mods).Generate().Frames.Cast<OsuReplayFrame>().ToList();
         }
     }
 }

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

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
@@ -16,10 +17,10 @@ namespace osu.Game.Rulesets.Osu.Mods
     {
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(OsuModAutopilot)).Append(typeof(OsuModSpunOut)).ToArray();
 
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "Autoplay" } },
-            Replay = new OsuAutoGenerator(beatmap).Generate()
+            Replay = new OsuAutoGenerator(beatmap, mods).Generate()
         };
     }
 }

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

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System;
+using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
@@ -16,10 +17,10 @@ namespace osu.Game.Rulesets.Osu.Mods
     {
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(OsuModAutopilot)).Append(typeof(OsuModSpunOut)).ToArray();
 
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "Autoplay" } },
-            Replay = new OsuAutoGenerator(beatmap).Generate()
+            Replay = new OsuAutoGenerator(beatmap, mods).Generate()
         };
     }
 }

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

@@ -0,0 +1,86 @@
+// 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.Collections.Generic;
+using System.Linq;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics.Sprites;
+using osu.Game.Configuration;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.Objects.Drawables;
+using osu.Game.Rulesets.Osu.UI;
+using osu.Game.Rulesets.UI;
+
+namespace osu.Game.Rulesets.Osu.Mods
+{
+    public class OsuModClassic : Mod, IApplicableToHitObject, IApplicableToDrawableHitObjects, IApplicableToDrawableRuleset<OsuHitObject>
+    {
+        public override string Name => "Classic";
+
+        public override string Acronym => "CL";
+
+        public override double ScoreMultiplier => 1;
+
+        public override IconUsage? Icon => FontAwesome.Solid.History;
+
+        public override string Description => "Feeling nostalgic?";
+
+        public override bool Ranked => false;
+
+        public override ModType Type => ModType.Conversion;
+
+        [SettingSource("No slider head accuracy requirement", "Scores sliders proportionally to the number of ticks hit.")]
+        public Bindable<bool> NoSliderHeadAccuracy { get; } = new BindableBool(true);
+
+        [SettingSource("No slider head movement", "Pins slider heads at their starting position, regardless of time.")]
+        public Bindable<bool> NoSliderHeadMovement { get; } = new BindableBool(true);
+
+        [SettingSource("Apply classic note lock", "Applies note lock to the full hit window.")]
+        public Bindable<bool> ClassicNoteLock { get; } = new BindableBool(true);
+
+        [SettingSource("Use fixed slider follow circle hit area", "Makes the slider follow circle track its final size at all times.")]
+        public Bindable<bool> FixedFollowCircleHitArea { get; } = new BindableBool(true);
+
+        public void ApplyToHitObject(HitObject hitObject)
+        {
+            switch (hitObject)
+            {
+                case Slider slider:
+                    slider.OnlyJudgeNestedObjects = !NoSliderHeadAccuracy.Value;
+
+                    foreach (var head in slider.NestedHitObjects.OfType<SliderHeadCircle>())
+                        head.JudgeAsNormalHitCircle = !NoSliderHeadAccuracy.Value;
+
+                    break;
+            }
+        }
+
+        public void ApplyToDrawableRuleset(DrawableRuleset<OsuHitObject> drawableRuleset)
+        {
+            var osuRuleset = (DrawableOsuRuleset)drawableRuleset;
+
+            if (ClassicNoteLock.Value)
+                osuRuleset.Playfield.HitPolicy = new ObjectOrderedHitPolicy();
+        }
+
+        public void ApplyToDrawableHitObjects(IEnumerable<DrawableHitObject> drawables)
+        {
+            foreach (var obj in drawables)
+            {
+                switch (obj)
+                {
+                    case DrawableSlider slider:
+                        slider.Ball.InputTracksVisualSize = !FixedFollowCircleHitArea.Value;
+                        break;
+
+                    case DrawableSliderHead head:
+                        head.TrackFollowCircle = !NoSliderHeadMovement.Value;
+                        break;
+                }
+            }
+        }
+    }
+}

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

@@ -12,7 +12,7 @@ namespace osu.Game.Rulesets.Osu.Mods
     public class OsuModDifficultyAdjust : ModDifficultyAdjust
     {
         [SettingSource("Circle Size", "Override a beatmap's set CS.", FIRST_SETTING_ORDER - 1)]
-        public BindableNumber<float> CircleSize { get; } = new BindableFloat
+        public BindableNumber<float> CircleSize { get; } = new BindableFloatWithLimitExtension
         {
             Precision = 0.1f,
             MinValue = 0,
@@ -22,7 +22,7 @@ namespace osu.Game.Rulesets.Osu.Mods
         };
 
         [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1)]
-        public BindableNumber<float> ApproachRate { get; } = new BindableFloat
+        public BindableNumber<float> ApproachRate { get; } = new BindableFloatWithLimitExtension
         {
             Precision = 0.1f,
             MinValue = 0,
@@ -31,6 +31,14 @@ namespace osu.Game.Rulesets.Osu.Mods
             Value = 5,
         };
 
+        protected override void ApplyLimits(bool extended)
+        {
+            base.ApplyLimits(extended);
+
+            CircleSize.MaxValue = extended ? 11 : 10;
+            ApproachRate.MaxValue = extended ? 11 : 10;
+        }
+
         public override string SettingDescription
         {
             get

osu.Game.Rulesets.Osu/Objects/Drawables/Connections/FollowPointConnection.cs

@@ -110,8 +110,13 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
             double startTime = start.GetEndTime();
             double duration = end.StartTime - startTime;
 
+            // Preempt time can go below 800ms. Normally, this is achieved via the DT mod which uniformly speeds up all animations game wide regardless of AR.
+            // This uniform speedup is hard to match 1:1, however we can at least make AR>10 (via mods) feel good by extending the upper linear preempt function (see: OsuHitObject).
+            // Note that this doesn't exactly match the AR>10 visuals as they're classically known, but it feels good.
+            double preempt = PREEMPT * Math.Min(1, start.TimePreempt / OsuHitObject.PREEMPT_MIN);
+
             fadeOutTime = startTime + fraction * duration;
-            fadeInTime = fadeOutTime - PREEMPT;
+            fadeInTime = fadeOutTime - preempt;
         }
     }
 }

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableHitCircle.cs

@@ -123,7 +123,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                 return;
             }
 
-            var result = HitObject.HitWindows.ResultFor(timeOffset);
+            var result = ResultFor(timeOffset);
 
             if (result == HitResult.None || CheckHittable?.Invoke(this, Time.Current) == false)
             {
@@ -146,6 +146,13 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             });
         }
 
+        /// <summary>
+        /// Retrieves the <see cref="HitResult"/> for a time offset.
+        /// </summary>
+        /// <param name="timeOffset">The time offset.</param>
+        /// <returns>The hit result, or <see cref="HitResult.None"/> if <paramref name="timeOffset"/> doesn't result in a judgement.</returns>
+        protected virtual HitResult ResultFor(double timeOffset) => HitObject.HitWindows.ResultFor(timeOffset);
+
         protected override void UpdateInitialTransforms()
         {
             base.UpdateInitialTransforms();

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableOsuJudgement.cs

@@ -39,7 +39,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
             if (JudgedObject?.HitObject is OsuHitObject osuObject)
             {
-                Position = osuObject.StackedPosition;
+                Position = osuObject.StackedEndPosition;
                 Scale = new Vector2(osuObject.Scale);
             }
         }

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableSlider.cs

@@ -15,6 +15,7 @@ using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Osu.Skinning;
 using osu.Game.Rulesets.Osu.Skinning.Default;
 using osu.Game.Rulesets.Osu.UI;
+using osu.Game.Rulesets.Scoring;
 using osuTK.Graphics;
 using osu.Game.Skinning;
 
@@ -30,7 +31,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         public SliderBall Ball { get; private set; }
         public SkinnableDrawable Body { get; private set; }
 
-        public override bool DisplayResult => false;
+        public override bool DisplayResult => !HitObject.OnlyJudgeNestedObjects;
 
         private PlaySliderBody sliderBody => Body.Drawable as PlaySliderBody;
 
@@ -249,7 +250,30 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             if (userTriggered || Time.Current < HitObject.EndTime)
                 return;
 
+            // If only the nested hitobjects are judged, then the slider's own judgement is ignored for scoring purposes.
+            // But the slider needs to still be judged with a reasonable hit/miss result for visual purposes (hit/miss transforms, etc).
+            if (HitObject.OnlyJudgeNestedObjects)
+            {
                 ApplyResult(r => r.Type = NestedHitObjects.Any(h => h.Result.IsHit) ? r.Judgement.MaxResult : r.Judgement.MinResult);
+                return;
+            }
+
+            // Otherwise, if this slider also needs to be judged, apply judgement proportionally to the number of nested hitobjects hit. This is the classic osu!stable scoring.
+            ApplyResult(r =>
+            {
+                int totalTicks = NestedHitObjects.Count;
+                int hitTicks = NestedHitObjects.Count(h => h.IsHit);
+
+                if (hitTicks == totalTicks)
+                    r.Type = HitResult.Great;
+                else if (hitTicks == 0)
+                    r.Type = HitResult.Miss;
+                else
+                {
+                    double hitFraction = (double)hitTicks / totalTicks;
+                    r.Type = hitFraction >= 0.5 ? HitResult.Ok : HitResult.Meh;
+                }
+            });
         }
 
         public override void PlaySamples()

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableSliderHead.cs

@@ -7,16 +7,27 @@ using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Rulesets.Scoring;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables
 {
     public class DrawableSliderHead : DrawableHitCircle
     {
+        public new SliderHeadCircle HitObject => (SliderHeadCircle)base.HitObject;
+
         [CanBeNull]
         public Slider Slider => DrawableSlider?.HitObject;
 
         protected DrawableSlider DrawableSlider => (DrawableSlider)ParentHitObject;
 
+        public override bool DisplayResult => HitObject?.JudgeAsNormalHitCircle ?? base.DisplayResult;
+
+        /// <summary>
+        /// Makes this <see cref="DrawableSliderHead"/> track the follow circle when the start time is reached.
+        /// If <c>false</c>, this <see cref="DrawableSliderHead"/> will be pinned to its initial position in the slider.
+        /// </summary>
+        public bool TrackFollowCircle = true;
+
         private readonly IBindable<int> pathVersion = new Bindable<int>();
 
         protected override OsuSkinComponents CirclePieceComponent => OsuSkinComponents.SliderHeadHitCircle;
@@ -59,13 +70,29 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             base.Update();
 
             Debug.Assert(Slider != null);
+            Debug.Assert(HitObject != null);
 
+            if (TrackFollowCircle)
+            {
                 double completionProgress = Math.Clamp((Time.Current - Slider.StartTime) / Slider.Duration, 0, 1);
 
                 //todo: we probably want to reconsider this before adding scoring, but it looks and feels nice.
                 if (!IsHit)
                     Position = Slider.CurvePositionAt(completionProgress);
             }
+        }
+
+        protected override HitResult ResultFor(double timeOffset)
+        {
+            Debug.Assert(HitObject != null);
+
+            if (HitObject.JudgeAsNormalHitCircle)
+                return base.ResultFor(timeOffset);
+
+            // If not judged as a normal hitcircle, judge as a slider tick instead. This is the classic osu!stable scoring.
+            var result = base.ResultFor(timeOffset);
+            return result.IsHit() ? HitResult.LargeTickHit : HitResult.LargeTickMiss;
+        }
 
         public Action<double> OnShake;
 

osu.Game.Rulesets.Osu/Objects/Drawables/DrawableSpinner.cs

@@ -130,7 +130,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         {
             if (tracking.NewValue)
             {
-                spinningSample?.Play(!spinningSample.IsPlaying);
+                if (!spinningSample.IsPlaying)
+                    spinningSample?.Play();
                 spinningSample?.VolumeTo(1, 300);
             }
             else

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

@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using System.Linq;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
@@ -25,6 +26,11 @@ namespace osu.Game.Rulesets.Osu.Objects
         /// </summary>
         internal const float BASE_SCORING_DISTANCE = 100;
 
+        /// <summary>
+        /// Minimum preempt time at AR=10.
+        /// </summary>
+        public const double PREEMPT_MIN = 450;
+
         public double TimePreempt = 600;
         public double TimeFadeIn = 400;
 
@@ -112,8 +118,13 @@ namespace osu.Game.Rulesets.Osu.Objects
         {
             base.ApplyDefaultsToSelf(controlPointInfo, difficulty);
 
-            TimePreempt = (float)BeatmapDifficulty.DifficultyRange(difficulty.ApproachRate, 1800, 1200, 450);
+            TimePreempt = (float)BeatmapDifficulty.DifficultyRange(difficulty.ApproachRate, 1800, 1200, PREEMPT_MIN);
-            TimeFadeIn = 400; // as per osu-stable
+
+            // Preempt time can go below 450ms. Normally, this is achieved via the DT mod which uniformly speeds up all animations game wide regardless of AR.
+            // This uniform speedup is hard to match 1:1, however we can at least make AR>10 (via mods) feel good by extending the upper linear function above.
+            // Note that this doesn't exactly match the AR>10 visuals as they're classically known, but it feels good.
+            // This adjustment is necessary for AR>10, otherwise TimePreempt can become smaller leading to hitcircles not fully fading in.
+            TimeFadeIn = 400 * Math.Min(1, TimePreempt / PREEMPT_MIN);
 
             Scale = (1.0f - 0.7f * (difficulty.CircleSize - 5) / 5) / 2;
         }

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

@@ -114,8 +114,14 @@ namespace osu.Game.Rulesets.Osu.Objects
         /// </summary>
         public double TickDistanceMultiplier = 1;
 
+        /// <summary>
+        /// Whether this <see cref="Slider"/>'s judgement is fully handled by its nested <see cref="HitObject"/>s.
+        /// If <c>false</c>, this <see cref="Slider"/> will be judged proportionally to the number of nested <see cref="HitObject"/>s hit.
+        /// </summary>
+        public bool OnlyJudgeNestedObjects = true;
+
         [JsonIgnore]
-        public HitCircle HeadCircle { get; protected set; }
+        public SliderHeadCircle HeadCircle { get; protected set; }
 
         [JsonIgnore]
         public SliderTailCircle TailCircle { get; protected set; }
@@ -140,7 +146,8 @@ namespace osu.Game.Rulesets.Osu.Objects
 
             // The samples should be attached to the slider tail, however this can only be done after LegacyLastTick is removed otherwise they would play earlier than they're intended to.
             // For now, the samples are attached to and played by the slider itself at the correct end time.
-            Samples = this.GetNodeSamples(repeatCount + 1);
+            // ToArray call is required as GetNodeSamples may fallback to Samples itself (without it it will get cleared due to the list reference being live).
+            Samples = this.GetNodeSamples(repeatCount + 1).ToArray();
         }
 
         protected override void CreateNestedHitObjects(CancellationToken cancellationToken)
@@ -233,7 +240,7 @@ namespace osu.Game.Rulesets.Osu.Objects
                 HeadCircle.Samples = this.GetNodeSamples(0);
         }
 
-        public override Judgement CreateJudgement() => new OsuIgnoreJudgement();
+        public override Judgement CreateJudgement() => OnlyJudgeNestedObjects ? new OsuIgnoreJudgement() : new OsuJudgement();
 
         protected override HitWindows CreateHitWindows() => HitWindows.Empty;
     }

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

@@ -1,9 +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.Judgements;
+using osu.Game.Rulesets.Osu.Judgements;
+
 namespace osu.Game.Rulesets.Osu.Objects
 {
     public class SliderHeadCircle : HitCircle
     {
+        /// <summary>
+        /// Whether to treat this <see cref="SliderHeadCircle"/> as a normal <see cref="HitCircle"/> for judgement purposes.
+        /// If <c>false</c>, this <see cref="SliderHeadCircle"/> will be judged as a <see cref="SliderTick"/> instead.
+        /// </summary>
+        public bool JudgeAsNormalHitCircle = true;
+
+        public override Judgement CreateJudgement() => JudgeAsNormalHitCircle ? base.CreateJudgement() : new SliderTickJudgement();
     }
 }

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

@@ -33,10 +33,5 @@ namespace osu.Game.Rulesets.Osu.Objects
         protected override HitWindows CreateHitWindows() => HitWindows.Empty;
 
         public override Judgement CreateJudgement() => new SliderTickJudgement();
-
-        public class SliderTickJudgement : OsuJudgement
-        {
-            public override HitResult MaxResult => HitResult.LargeTickHit;
-        }
     }
 }

osu.Game.Rulesets.Osu/OsuRuleset.cs

@@ -163,6 +163,7 @@ namespace osu.Game.Rulesets.Osu
                     {
                         new OsuModTarget(),
                         new OsuModDifficultyAdjust(),
+                        new OsuModClassic()
                     };
 
                 case ModType.Automation:

osu.Game.Rulesets.Osu/Replays/OsuAutoGenerator.cs

@@ -6,10 +6,12 @@ using osu.Framework.Utils;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Osu.Objects;
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
 using osu.Framework.Graphics;
 using osu.Game.Replays;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Osu.Beatmaps;
 using osu.Game.Rulesets.Osu.Scoring;
@@ -33,11 +35,6 @@ namespace osu.Game.Rulesets.Osu.Replays
 
         #region Constants
 
-        /// <summary>
-        /// The "reaction time" in ms between "seeing" a new hit object and moving to "react" to it.
-        /// </summary>
-        private readonly double reactionTime;
-
         private readonly HitWindows defaultHitWindows;
 
         /// <summary>
@@ -49,12 +46,9 @@ namespace osu.Game.Rulesets.Osu.Replays
 
         #region Construction / Initialisation
 
-        public OsuAutoGenerator(IBeatmap beatmap)
+        public OsuAutoGenerator(IBeatmap beatmap, IReadOnlyList<Mod> mods)
-            : base(beatmap)
+            : base(beatmap, mods)
         {
-            // Already superhuman, but still somewhat realistic
-            reactionTime = ApplyModsToRate(100);
-
             defaultHitWindows = new OsuHitWindows();
             defaultHitWindows.SetDifficulty(Beatmap.BeatmapInfo.BaseDifficulty.OverallDifficulty);
         }
@@ -240,7 +234,7 @@ namespace osu.Game.Rulesets.Osu.Replays
             OsuReplayFrame lastFrame = (OsuReplayFrame)Frames[^1];
 
             // Wait until Auto could "see and react" to the next note.
-            double waitTime = h.StartTime - Math.Max(0.0, h.TimePreempt - reactionTime);
+            double waitTime = h.StartTime - Math.Max(0.0, h.TimePreempt - getReactionTime(h.StartTime - h.TimePreempt));
 
             if (waitTime > lastFrame.Time)
             {
@@ -250,7 +244,7 @@ namespace osu.Game.Rulesets.Osu.Replays
 
             Vector2 lastPosition = lastFrame.Position;
 
-            double timeDifference = ApplyModsToTime(h.StartTime - lastFrame.Time);
+            double timeDifference = ApplyModsToTimeDelta(lastFrame.Time, h.StartTime);
 
             // Only "snap" to hitcircles if they are far enough apart. As the time between hitcircles gets shorter the snapping threshold goes up.
             if (timeDifference > 0 && // Sanity checks
@@ -258,7 +252,7 @@ namespace osu.Game.Rulesets.Osu.Replays
                  timeDifference >= 266)) // ... or the beats are slow enough to tap anyway.
             {
                 // Perform eased movement
-                for (double time = lastFrame.Time + FrameDelay; time < h.StartTime; time += FrameDelay)
+                for (double time = lastFrame.Time + GetFrameDelay(lastFrame.Time); time < h.StartTime; time += GetFrameDelay(time))
                 {
                     Vector2 currentPosition = Interpolation.ValueAt(time, lastPosition, targetPos, lastFrame.Time, h.StartTime, easing);
                     AddFrameToReplay(new OsuReplayFrame((int)time, new Vector2(currentPosition.X, currentPosition.Y)) { Actions = lastFrame.Actions });
@@ -272,6 +266,14 @@ namespace osu.Game.Rulesets.Osu.Replays
             }
         }
 
+        /// <summary>
+        /// Calculates the "reaction time" in ms between "seeing" a new hit object and moving to "react" to it.
+        /// </summary>
+        /// <remarks>
+        /// Already superhuman, but still somewhat realistic.
+        /// </remarks>
+        private double getReactionTime(double timeInstant) => ApplyModsToRate(timeInstant, 100);
+
         // Add frames to click the hitobject
         private void addHitObjectClickFrames(OsuHitObject h, Vector2 startPosition, float spinnerDirection)
         {
@@ -341,17 +343,23 @@ namespace osu.Game.Rulesets.Osu.Replays
                     float angle = radius == 0 ? 0 : MathF.Atan2(difference.Y, difference.X);
 
                     double t;
+                    double previousFrame = h.StartTime;
 
-                    for (double j = h.StartTime + FrameDelay; j < spinner.EndTime; j += FrameDelay)
+                    for (double nextFrame = h.StartTime + GetFrameDelay(h.StartTime); nextFrame < spinner.EndTime; nextFrame += GetFrameDelay(nextFrame))
                     {
-                        t = ApplyModsToTime(j - h.StartTime) * spinnerDirection;
+                        t = ApplyModsToTimeDelta(previousFrame, nextFrame) * spinnerDirection;
+                        angle += (float)t / 20;
 
-                        Vector2 pos = SPINNER_CENTRE + CirclePosition(t / 20 + angle, SPIN_RADIUS);
+                        Vector2 pos = SPINNER_CENTRE + CirclePosition(angle, SPIN_RADIUS);
-                        AddFrameToReplay(new OsuReplayFrame((int)j, new Vector2(pos.X, pos.Y), action));
+                        AddFrameToReplay(new OsuReplayFrame((int)nextFrame, new Vector2(pos.X, pos.Y), action));
+
+                        previousFrame = nextFrame;
                     }
 
-                    t = ApplyModsToTime(spinner.EndTime - h.StartTime) * spinnerDirection;
+                    t = ApplyModsToTimeDelta(previousFrame, spinner.EndTime) * spinnerDirection;
-                    Vector2 endPosition = SPINNER_CENTRE + CirclePosition(t / 20 + angle, SPIN_RADIUS);
+                    angle += (float)t / 20;
+
+                    Vector2 endPosition = SPINNER_CENTRE + CirclePosition(angle, SPIN_RADIUS);
 
                     AddFrameToReplay(new OsuReplayFrame(spinner.EndTime, new Vector2(endPosition.X, endPosition.Y), action));
 
@@ -359,7 +367,7 @@ namespace osu.Game.Rulesets.Osu.Replays
                     break;
 
                 case Slider slider:
-                    for (double j = FrameDelay; j < slider.Duration; j += FrameDelay)
+                    for (double j = GetFrameDelay(slider.StartTime); j < slider.Duration; j += GetFrameDelay(slider.StartTime + j))
                     {
                         Vector2 pos = slider.StackedPositionAt(j / slider.Duration);
                         AddFrameToReplay(new OsuReplayFrame(h.StartTime + j, new Vector2(pos.X, pos.Y), action));

osu.Game.Rulesets.Osu/Replays/OsuAutoGeneratorBase.cs

@@ -5,7 +5,9 @@ using osuTK;
 using osu.Game.Beatmaps;
 using System;
 using System.Collections.Generic;
+using System.Linq;
 using osu.Game.Replays;
+using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Osu.UI;
 using osu.Game.Rulesets.Replays;
 
@@ -22,33 +24,61 @@ namespace osu.Game.Rulesets.Osu.Replays
 
         public const float SPIN_RADIUS = 50;
 
-        /// <summary>
-        /// The time in ms between each ReplayFrame.
-        /// </summary>
-        protected readonly double FrameDelay;
-
         #endregion
 
         #region Construction / Initialisation
 
         protected Replay Replay;
         protected List<ReplayFrame> Frames => Replay.Frames;
+        private readonly IReadOnlyList<IApplicableToRate> timeAffectingMods;
 
-        protected OsuAutoGeneratorBase(IBeatmap beatmap)
+        protected OsuAutoGeneratorBase(IBeatmap beatmap, IReadOnlyList<Mod> mods)
             : base(beatmap)
         {
             Replay = new Replay();
 
-            // We are using ApplyModsToRate and not ApplyModsToTime to counteract the speed up / slow down from HalfTime / DoubleTime so that we remain at a constant framerate of 60 fps.
+            timeAffectingMods = mods.OfType<IApplicableToRate>().ToList();
-            FrameDelay = ApplyModsToRate(1000.0 / 60.0);
         }
 
         #endregion
 
         #region Utilities
 
-        protected double ApplyModsToTime(double v) => v;
+        /// <summary>
-        protected double ApplyModsToRate(double v) => v;
+        /// Returns the real duration of time between <paramref name="startTime"/> and <paramref name="endTime"/>
+        /// after applying rate-affecting mods.
+        /// </summary>
+        /// <remarks>
+        /// This method should only be used when <paramref name="startTime"/> and <paramref name="endTime"/> are very close.
+        /// That is because the track rate might be changing with time,
+        /// and the method used here is a rough instantaneous approximation.
+        /// </remarks>
+        /// <param name="startTime">The start time of the time delta, in original track time.</param>
+        /// <param name="endTime">The end time of the time delta, in original track time.</param>
+        protected double ApplyModsToTimeDelta(double startTime, double endTime)
+        {
+            double delta = endTime - startTime;
+
+            foreach (var mod in timeAffectingMods)
+                delta /= mod.ApplyToRate(startTime);
+
+            return delta;
+        }
+
+        protected double ApplyModsToRate(double time, double rate)
+        {
+            foreach (var mod in timeAffectingMods)
+                rate = mod.ApplyToRate(time, rate);
+            return rate;
+        }
+
+        /// <summary>
+        /// Calculates the interval after which the next <see cref="ReplayFrame"/> should be generated,
+        /// in milliseconds.
+        /// </summary>
+        /// <param name="time">The time of the previous frame.</param>
+        protected double GetFrameDelay(double time)
+            => ApplyModsToRate(time, 1000.0 / 60);
 
         private class ReplayFrameComparer : IComparer<ReplayFrame>
         {

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

@@ -21,6 +21,8 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
         [Resolved(CanBeNull = true)]
         private OsuRulesetConfigManager config { get; set; }
 
+        private readonly Bindable<bool> configSnakingOut = new Bindable<bool>();
+
         [BackgroundDependencyLoader]
         private void load(ISkinSource skin, DrawableHitObject drawableObject)
         {
@@ -36,10 +38,28 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
             accentColour.BindValueChanged(accent => updateAccentColour(skin, accent.NewValue), true);
 
             config?.BindWith(OsuRulesetSetting.SnakingInSliders, SnakingIn);
-            config?.BindWith(OsuRulesetSetting.SnakingOutSliders, SnakingOut);
+            config?.BindWith(OsuRulesetSetting.SnakingOutSliders, configSnakingOut);
+
+            SnakingOut.BindTo(configSnakingOut);
 
             BorderSize = skin.GetConfig<OsuSkinConfiguration, float>(OsuSkinConfiguration.SliderBorderSize)?.Value ?? 1;
             BorderColour = skin.GetConfig<OsuSkinColour, Color4>(OsuSkinColour.SliderBorder)?.Value ?? Color4.White;
+
+            drawableObject.HitObjectApplied += onHitObjectApplied;
+        }
+
+        private void onHitObjectApplied(DrawableHitObject obj)
+        {
+            var drawableSlider = (DrawableSlider)obj;
+            if (drawableSlider.HitObject == null)
+                return;
+
+            // When not tracking the follow circle, unbind from the config and forcefully disable snaking out - it looks better that way.
+            if (!drawableSlider.HeadCircle.TrackFollowCircle)
+            {
+                SnakingOut.UnbindFrom(configSnakingOut);
+                SnakingOut.Value = false;
+            }
         }
 
         private void updateAccentColour(ISkinSource skin, Color4 defaultAccentColour)

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

@@ -31,6 +31,12 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
             set => ball.Colour = value;
         }
 
+        /// <summary>
+        /// Whether to track accurately to the visual size of this <see cref="SliderBall"/>.
+        /// If <c>false</c>, tracking will be performed at the final scale at all times.
+        /// </summary>
+        public bool InputTracksVisualSize = true;
+
         private readonly Drawable followCircle;
         private readonly DrawableSlider drawableSlider;
         private readonly Drawable ball;
@@ -94,7 +100,14 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
 
                 tracking = value;
 
+                if (InputTracksVisualSize)
                     followCircle.ScaleTo(tracking ? 2.4f : 1f, 300, Easing.OutQuint);
+                else
+                {
+                    // We need to always be tracking the final size, at both endpoints. For now, this is achieved by removing the scale duration.
+                    followCircle.ScaleTo(tracking ? 2.4f : 1f);
+                }
+
                 followCircle.FadeTo(tracking ? 1f : 0, 300, Easing.OutQuint);
             }
         }

osu.Game.Rulesets.Osu/UI/ObjectOrderedHitPolicy.cs

@@ -0,0 +1,54 @@
+// 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.Collections.Generic;
+using System.Linq;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.Osu.Objects.Drawables;
+using osu.Game.Rulesets.UI;
+
+namespace osu.Game.Rulesets.Osu.UI
+{
+    /// <summary>
+    /// Ensures that <see cref="HitObject"/>s are hit in order of appearance. The classic note lock.
+    /// <remarks>
+    /// Hits will be blocked until the previous <see cref="HitObject"/>s have been judged.
+    /// </remarks>
+    /// </summary>
+    public class ObjectOrderedHitPolicy : IHitPolicy
+    {
+        public IHitObjectContainer HitObjectContainer { get; set; }
+
+        public bool IsHittable(DrawableHitObject hitObject, double time) => enumerateHitObjectsUpTo(hitObject.HitObject.StartTime).All(obj => obj.AllJudged);
+
+        public void HandleHit(DrawableHitObject hitObject)
+        {
+        }
+
+        private IEnumerable<DrawableHitObject> enumerateHitObjectsUpTo(double targetTime)
+        {
+            foreach (var obj in HitObjectContainer.AliveObjects)
+            {
+                if (obj.HitObject.StartTime >= targetTime)
+                    yield break;
+
+                switch (obj)
+                {
+                    case DrawableSpinner _:
+                        continue;
+
+                    case DrawableSlider slider:
+                        yield return slider.HeadCircle;
+
+                        break;
+
+                    default:
+                        yield return obj;
+
+                        break;
+                }
+            }
+        }
+    }
+}

osu.Game.Rulesets.Osu/UI/OsuPlayfield.cs

@@ -31,7 +31,6 @@ namespace osu.Game.Rulesets.Osu.UI
         private readonly ProxyContainer spinnerProxies;
         private readonly JudgementContainer<DrawableOsuJudgement> judgementLayer;
         private readonly FollowPointRenderer followPoints;
-        private readonly StartTimeOrderedHitPolicy hitPolicy;
 
         public static readonly Vector2 BASE_SIZE = new Vector2(512, 384);
 
@@ -54,10 +53,9 @@ namespace osu.Game.Rulesets.Osu.UI
                 approachCircles = new ProxyContainer { RelativeSizeAxes = Axes.Both },
             };
 
-            hitPolicy = new StartTimeOrderedHitPolicy { HitObjectContainer = HitObjectContainer };
+            HitPolicy = new StartTimeOrderedHitPolicy();
 
             var hitWindows = new OsuHitWindows();
-
             foreach (var result in Enum.GetValues(typeof(HitResult)).OfType<HitResult>().Where(r => r > HitResult.None && hitWindows.IsHitResultAllowed(r)))
                 poolDictionary.Add(result, new DrawableJudgementPool(result, onJudgmentLoaded));
 
@@ -66,6 +64,18 @@ namespace osu.Game.Rulesets.Osu.UI
             NewResult += onNewResult;
         }
 
+        private IHitPolicy hitPolicy;
+
+        public IHitPolicy HitPolicy
+        {
+            get => hitPolicy;
+            set
+            {
+                hitPolicy = value ?? throw new ArgumentNullException(nameof(value));
+                hitPolicy.HitObjectContainer = HitObjectContainer;
+            }
+        }
+
         protected override void OnNewDrawableHitObject(DrawableHitObject drawable)
         {
             ((DrawableOsuHitObject)drawable).CheckHittable = hitPolicy.IsHittable;

osu.Game.Rulesets.Taiko.Tests/osu.Game.Rulesets.Taiko.Tests.csproj

@@ -3,7 +3,7 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>

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

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Taiko.Objects;
@@ -12,7 +13,7 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModAutoplay : ModAutoplay<TaikoHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "mekkadosu!" } },
             Replay = new TaikoAutoGenerator(beatmap).Generate(),

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

@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Taiko.Objects;
@@ -12,7 +13,7 @@ namespace osu.Game.Rulesets.Taiko.Mods
 {
     public class TaikoModCinema : ModCinema<TaikoHitObject>
     {
-        public override Score CreateReplayScore(IBeatmap beatmap) => new Score
+        public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {
             ScoreInfo = new ScoreInfo { User = new User { Username = "mekkadosu!" } },
             Replay = new TaikoAutoGenerator(beatmap).Generate(),

osu.Game.Rulesets.Taiko/Skinning/Legacy/TaikoLegacySkinTransformer.cs

@@ -152,7 +152,7 @@ namespace osu.Game.Rulesets.Taiko.Skinning.Legacy
             throw new ArgumentOutOfRangeException(nameof(component), $"Invalid component type: {component}");
         }
 
-        public override SampleChannel GetSample(ISampleInfo sampleInfo) => Source.GetSample(new LegacyTaikoSampleInfo(sampleInfo));
+        public override Sample GetSample(ISampleInfo sampleInfo) => Source.GetSample(new LegacyTaikoSampleInfo(sampleInfo));
 
         public override IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => Source.GetConfig<TLookup, TValue>(lookup);
 

osu.Game.Tests/Chat/MessageFormatterTests.cs

@@ -21,6 +21,27 @@ namespace osu.Game.Tests.Chat
             Assert.AreEqual(36, result.Links[0].Length);
         }
 
+        [TestCase(LinkAction.OpenBeatmap, "456", "https://dev.ppy.sh/beatmapsets/123#osu/456")]
+        [TestCase(LinkAction.OpenBeatmap, "456", "https://dev.ppy.sh/beatmapsets/123#osu/456?whatever")]
+        [TestCase(LinkAction.OpenBeatmap, "456", "https://dev.ppy.sh/beatmapsets/123/456")]
+        [TestCase(LinkAction.External, null, "https://dev.ppy.sh/beatmapsets/abc/def")]
+        [TestCase(LinkAction.OpenBeatmapSet, "123", "https://dev.ppy.sh/beatmapsets/123")]
+        [TestCase(LinkAction.OpenBeatmapSet, "123", "https://dev.ppy.sh/beatmapsets/123/whatever")]
+        [TestCase(LinkAction.External, null, "https://dev.ppy.sh/beatmapsets/abc")]
+        public void TestBeatmapLinks(LinkAction expectedAction, string expectedArg, string link)
+        {
+            MessageFormatter.WebsiteRootUrl = "dev.ppy.sh";
+
+            Message result = MessageFormatter.FormatMessage(new Message { Content = link });
+
+            Assert.AreEqual(result.Content, result.DisplayContent);
+            Assert.AreEqual(1, result.Links.Count);
+            Assert.AreEqual(expectedAction, result.Links[0].Action);
+            Assert.AreEqual(expectedArg, result.Links[0].Argument);
+            if (expectedAction == LinkAction.External)
+                Assert.AreEqual(link, result.Links[0].Url);
+        }
+
         [Test]
         public void TestMultipleComplexLinks()
         {

osu.Game.Tests/Gameplay/TestSceneHitObjectAccentColour.cs

@@ -121,7 +121,7 @@ namespace osu.Game.Tests.Gameplay
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => throw new NotImplementedException();
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup)
             {

osu.Game.Tests/Gameplay/TestSceneStoryboardSamples.cs

@@ -35,7 +35,7 @@ namespace osu.Game.Tests.Gameplay
         public void TestRetrieveTopLevelSample()
         {
             ISkin skin = null;
-            SampleChannel channel = null;
+            Sample channel = null;
 
             AddStep("create skin", () => skin = new TestSkin("test-sample", this));
             AddStep("retrieve sample", () => channel = skin.GetSample(new SampleInfo("test-sample")));
@@ -47,7 +47,7 @@ namespace osu.Game.Tests.Gameplay
         public void TestRetrieveSampleInSubFolder()
         {
             ISkin skin = null;
-            SampleChannel channel = null;
+            Sample channel = null;
 
             AddStep("create skin", () => skin = new TestSkin("folder/test-sample", this));
             AddStep("retrieve sample", () => channel = skin.GetSample(new SampleInfo("folder/test-sample")));

osu.Game.Tests/NonVisual/Skinning/LegacySkinAnimationTest.cs

@@ -59,7 +59,7 @@ namespace osu.Game.Tests.NonVisual.Skinning
             }
 
             public Drawable GetDrawableComponent(ISkinComponent component) => throw new NotSupportedException();
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotSupportedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotSupportedException();
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => throw new NotSupportedException();
         }
 

osu.Game.Tests/Online/TestAPIModJsonSerialization.cs

@@ -68,12 +68,29 @@ namespace osu.Game.Tests.Online
             Assert.That(converted.FinalRate.Value, Is.EqualTo(0.25));
         }
 
+        [Test]
+        public void TestDeserialiseDifficultyAdjustModWithExtendedLimits()
+        {
+            var apiMod = new APIMod(new TestModDifficultyAdjust
+            {
+                OverallDifficulty = { Value = 11 },
+                ExtendedLimits = { Value = true }
+            });
+
+            var deserialised = JsonConvert.DeserializeObject<APIMod>(JsonConvert.SerializeObject(apiMod));
+            var converted = (TestModDifficultyAdjust)deserialised.ToMod(new TestRuleset());
+
+            Assert.That(converted.ExtendedLimits.Value, Is.True);
+            Assert.That(converted.OverallDifficulty.Value, Is.EqualTo(11));
+        }
+
         private class TestRuleset : Ruleset
         {
             public override IEnumerable<Mod> GetModsFor(ModType type) => new Mod[]
             {
                 new TestMod(),
                 new TestModTimeRamp(),
+                new TestModDifficultyAdjust()
             };
 
             public override DrawableRuleset CreateDrawableRulesetWith(IBeatmap beatmap, IReadOnlyList<Mod> mods = null) => throw new System.NotImplementedException();
@@ -135,5 +152,9 @@ namespace osu.Game.Tests.Online
                 Value = true
             };
         }
+
+        private class TestModDifficultyAdjust : ModDifficultyAdjust
+        {
+        }
     }
 }

osu.Game.Tests/Rulesets/TestSceneDrawableRulesetDependencies.cs

@@ -105,9 +105,9 @@ namespace osu.Game.Tests.Rulesets
                 IsDisposed = true;
             }
 
-            public SampleChannel Get(string name) => null;
+            public Sample Get(string name) => null;
 
-            public Task<SampleChannel> GetAsync(string name) => null;
+            public Task<Sample> GetAsync(string name) => null;
 
             public Stream GetStream(string name) => null;
 

osu.Game.Tests/Skins/TestSceneSkinConfigurationLookup.cs

@@ -219,7 +219,7 @@ namespace osu.Game.Tests.Skins
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => skin.GetTexture(componentName, wrapModeS, wrapModeT);
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => skin.GetSample(sampleInfo);
+            public Sample GetSample(ISampleInfo sampleInfo) => skin.GetSample(sampleInfo);
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => skin.GetConfig<TLookup, TValue>(lookup);
         }

osu.Game.Tests/Visual/Editing/TestSceneEditorSamplePlayback.cs

@@ -3,11 +3,11 @@
 
 using System.Linq;
 using NUnit.Framework;
-using osu.Framework.Graphics.Audio;
 using osu.Framework.Testing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Osu;
 using osu.Game.Rulesets.Osu.Objects.Drawables;
+using osu.Game.Skinning;
 
 namespace osu.Game.Tests.Visual.Editing
 {
@@ -19,14 +19,14 @@ namespace osu.Game.Tests.Visual.Editing
         public void TestSlidingSampleStopsOnSeek()
         {
             DrawableSlider slider = null;
-            DrawableSample[] loopingSamples = null;
+            PoolableSkinnableSample[] loopingSamples = null;
-            DrawableSample[] onceOffSamples = null;
+            PoolableSkinnableSample[] onceOffSamples = null;
 
             AddStep("get first slider", () =>
             {
                 slider = Editor.ChildrenOfType<DrawableSlider>().OrderBy(s => s.HitObject.StartTime).First();
-                onceOffSamples = slider.ChildrenOfType<DrawableSample>().Where(s => !s.Looping).ToArray();
+                onceOffSamples = slider.ChildrenOfType<PoolableSkinnableSample>().Where(s => !s.Looping).ToArray();
-                loopingSamples = slider.ChildrenOfType<DrawableSample>().Where(s => s.Looping).ToArray();
+                loopingSamples = slider.ChildrenOfType<PoolableSkinnableSample>().Where(s => s.Looping).ToArray();
             });
 
             AddStep("start playback", () => EditorClock.Start());

osu.Game.Tests/Visual/Gameplay/TestSceneGameplaySamplePlayback.cs

@@ -4,7 +4,6 @@
 using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
-using osu.Framework.Graphics.Audio;
 using osu.Framework.Testing;
 using osu.Game.Rulesets;
 using osu.Game.Rulesets.Osu;
@@ -20,14 +19,14 @@ namespace osu.Game.Tests.Visual.Gameplay
         public void TestAllSamplesStopDuringSeek()
         {
             DrawableSlider slider = null;
-            DrawableSample[] samples = null;
+            PoolableSkinnableSample[] samples = null;
             ISamplePlaybackDisabler sampleDisabler = null;
 
             AddUntilStep("get variables", () =>
             {
                 sampleDisabler = Player;
                 slider = Player.ChildrenOfType<DrawableSlider>().OrderBy(s => s.HitObject.StartTime).FirstOrDefault();
-                samples = slider?.ChildrenOfType<DrawableSample>().ToArray();
+                samples = slider?.ChildrenOfType<PoolableSkinnableSample>().ToArray();
 
                 return slider != null;
             });

osu.Game.Tests/Visual/Gameplay/TestSceneReplay.cs

@@ -19,7 +19,7 @@ namespace osu.Game.Tests.Visual.Gameplay
         {
             var beatmap = Beatmap.Value.GetPlayableBeatmap(ruleset.RulesetInfo, Array.Empty<Mod>());
 
-            return new ScoreAccessibleReplayPlayer(ruleset.GetAutoplayMod()?.CreateReplayScore(beatmap));
+            return new ScoreAccessibleReplayPlayer(ruleset.GetAutoplayMod()?.CreateReplayScore(beatmap, Array.Empty<Mod>()));
         }
 
         protected override void AddCheckSteps()

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableDrawable.cs

@@ -298,7 +298,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => throw new NotImplementedException();
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => throw new NotImplementedException();
         }
@@ -309,7 +309,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => throw new NotImplementedException();
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => throw new NotImplementedException();
         }
@@ -321,7 +321,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => throw new NotImplementedException();
 
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
+            public Sample GetSample(ISampleInfo sampleInfo) => throw new NotImplementedException();
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => throw new NotImplementedException();
 

osu.Game.Tests/Visual/Gameplay/TestSceneSkinnableSound.cs

@@ -43,70 +43,60 @@ namespace osu.Game.Tests.Visual.Gameplay
         [Test]
         public void TestStoppedSoundDoesntResumeAfterPause()
         {
-            DrawableSample sample = null;
             AddStep("start sample with looping", () =>
             {
-                sample = skinnableSound.ChildrenOfType<DrawableSample>().First();
-
                 skinnableSound.Looping = true;
                 skinnableSound.Play();
             });
 
-            AddUntilStep("wait for sample to start playing", () => sample.Playing);
+            AddUntilStep("wait for sample to start playing", () => skinnableSound.IsPlaying);
 
             AddStep("stop sample", () => skinnableSound.Stop());
 
-            AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
+            AddUntilStep("wait for sample to stop playing", () => !skinnableSound.IsPlaying);
 
             AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
 
             AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
             AddWaitStep("wait a bit", 5);
-            AddAssert("sample not playing", () => !sample.Playing);
+            AddAssert("sample not playing", () => !skinnableSound.IsPlaying);
         }
 
         [Test]
         public void TestLoopingSoundResumesAfterPause()
         {
-            DrawableSample sample = null;
             AddStep("start sample with looping", () =>
             {
                 skinnableSound.Looping = true;
                 skinnableSound.Play();
-                sample = skinnableSound.ChildrenOfType<DrawableSample>().First();
             });
 
-            AddUntilStep("wait for sample to start playing", () => sample.Playing);
+            AddUntilStep("wait for sample to start playing", () => skinnableSound.IsPlaying);
 
             AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
-            AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
+            AddUntilStep("wait for sample to stop playing", () => !skinnableSound.IsPlaying);
 
             AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
-            AddUntilStep("wait for sample to start playing", () => sample.Playing);
+            AddUntilStep("wait for sample to start playing", () => skinnableSound.IsPlaying);
         }
 
         [Test]
         public void TestNonLoopingStopsWithPause()
         {
-            DrawableSample sample = null;
+            AddStep("start sample", () => skinnableSound.Play());
-            AddStep("start sample", () =>
-            {
-                skinnableSound.Play();
-                sample = skinnableSound.ChildrenOfType<DrawableSample>().First();
-            });
 
-            AddAssert("sample playing", () => sample.Playing);
+            AddAssert("sample playing", () => skinnableSound.IsPlaying);
 
             AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
 
-            AddUntilStep("sample not playing", () => !sample.Playing);
+            AddUntilStep("sample not playing", () => !skinnableSound.IsPlaying);
 
             AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
-            AddAssert("sample not playing", () => !sample.Playing);
+            AddAssert("sample not playing", () => !skinnableSound.IsPlaying);
-            AddAssert("sample not playing", () => !sample.Playing);
+            AddAssert("sample not playing", () => !skinnableSound.IsPlaying);
-            AddAssert("sample not playing", () => !sample.Playing);
+            AddAssert("sample not playing", () => !skinnableSound.IsPlaying);
         }
 
         [Test]
@@ -119,10 +109,10 @@ namespace osu.Game.Tests.Visual.Gameplay
                 sample = skinnableSound.ChildrenOfType<DrawableSample>().Single();
             });
 
-            AddAssert("sample playing", () => sample.Playing);
+            AddAssert("sample playing", () => skinnableSound.IsPlaying);
 
             AddStep("disable sample playback", () => skinSource.SamplePlaybackDisabled.Value = true);
-            AddUntilStep("wait for sample to stop playing", () => !sample.Playing);
+            AddUntilStep("wait for sample to stop playing", () => !skinnableSound.IsPlaying);
 
             AddStep("trigger skin change", () => skinSource.TriggerSourceChanged());
 
@@ -133,11 +123,11 @@ namespace osu.Game.Tests.Visual.Gameplay
                 return sample != oldSample;
             });
 
-            AddAssert("new sample stopped", () => !sample.Playing);
+            AddAssert("new sample stopped", () => !skinnableSound.IsPlaying);
             AddStep("enable sample playback", () => skinSource.SamplePlaybackDisabled.Value = false);
 
             AddWaitStep("wait a bit", 5);
-            AddAssert("new sample not played", () => !sample.Playing);
+            AddAssert("new sample not played", () => !skinnableSound.IsPlaying);
         }
 
         [Cached(typeof(ISkinSource))]
@@ -155,7 +145,7 @@ namespace osu.Game.Tests.Visual.Gameplay
 
             public Drawable GetDrawableComponent(ISkinComponent component) => source?.GetDrawableComponent(component);
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => source?.GetTexture(componentName, wrapModeS, wrapModeT);
-            public SampleChannel GetSample(ISampleInfo sampleInfo) => source?.GetSample(sampleInfo);
+            public Sample GetSample(ISampleInfo sampleInfo) => source?.GetSample(sampleInfo);
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => source?.GetConfig<TLookup, TValue>(lookup);
 
             public void TriggerSourceChanged()

osu.Game.Tests/Visual/Gameplay/TestSceneSpectator.cs

@@ -3,7 +3,6 @@
 
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading.Tasks;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
@@ -244,11 +243,6 @@ namespace osu.Game.Tests.Visual.Gameplay
             {
             }
 
-            protected override Task Connect()
-            {
-                return Task.CompletedTask;
-            }
-
             public void StartPlay(int beatmapId)
             {
                 this.beatmapId = beatmapId;

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

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using System.Threading.Tasks;
 using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
@@ -163,8 +162,6 @@ namespace osu.Game.Tests.Visual.Multiplayer
                     ((ISpectatorClient)this).UserSentFrames(userId, new FrameDataBundle(header, Array.Empty<LegacyReplayFrame>()));
                 }
             }
-
-            protected override Task Connect() => Task.CompletedTask;
         }
     }
 }

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

@@ -103,26 +103,26 @@ namespace osu.Game.Tests.Visual.Online
         private void testLinksGeneral()
         {
             addMessageWithChecks("test!");
-            addMessageWithChecks("osu.ppy.sh!");
+            addMessageWithChecks("dev.ppy.sh!");
-            addMessageWithChecks("https://osu.ppy.sh!", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("https://dev.ppy.sh!", 1, expectedActions: LinkAction.External);
             addMessageWithChecks("00:12:345 (1,2) - Test?", 1, expectedActions: LinkAction.OpenEditorTimestamp);
             addMessageWithChecks("Wiki link for tasty [[Performance Points]]", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("(osu forums)[https://osu.ppy.sh/forum] (old link format)", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("(osu forums)[https://dev.ppy.sh/forum] (old link format)", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("[https://osu.ppy.sh/home New site] (new link format)", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("[https://dev.ppy.sh/home New site] (new link format)", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("[osu forums](https://osu.ppy.sh/forum) (new link format 2)", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("[osu forums](https://dev.ppy.sh/forum) (new link format 2)", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("[https://osu.ppy.sh/home This is only a link to the new osu webpage but this is supposed to test word wrap.]", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("[https://dev.ppy.sh/home This is only a link to the new osu webpage but this is supposed to test word wrap.]", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("is now listening to [https://osu.ppy.sh/s/93523 IMAGE -MATERIAL- <Version 0>]", 1, true, expectedActions: LinkAction.OpenBeatmapSet);
+            addMessageWithChecks("is now listening to [https://dev.ppy.sh/s/93523 IMAGE -MATERIAL- <Version 0>]", 1, true, expectedActions: LinkAction.OpenBeatmapSet);
-            addMessageWithChecks("is now playing [https://osu.ppy.sh/b/252238 IMAGE -MATERIAL- <Version 0>]", 1, true, expectedActions: LinkAction.OpenBeatmap);
+            addMessageWithChecks("is now playing [https://dev.ppy.sh/b/252238 IMAGE -MATERIAL- <Version 0>]", 1, true, expectedActions: LinkAction.OpenBeatmap);
-            addMessageWithChecks("Let's (try)[https://osu.ppy.sh/home] [https://osu.ppy.sh/b/252238 multiple links] https://osu.ppy.sh/home", 3,
+            addMessageWithChecks("Let's (try)[https://dev.ppy.sh/home] [https://dev.ppy.sh/b/252238 multiple links] https://dev.ppy.sh/home", 3,
                 expectedActions: new[] { LinkAction.External, LinkAction.OpenBeatmap, LinkAction.External });
-            addMessageWithChecks("[https://osu.ppy.sh/home New link format with escaped [and \\[ paired] braces]", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("[https://dev.ppy.sh/home New link format with escaped [and \\[ paired] braces]", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("[Markdown link format with escaped [and \\[ paired] braces](https://osu.ppy.sh/home)", 1, expectedActions: LinkAction.External);
+            addMessageWithChecks("[Markdown link format with escaped [and \\[ paired] braces](https://dev.ppy.sh/home)", 1, expectedActions: LinkAction.External);
-            addMessageWithChecks("(Old link format with escaped (and \\( paired) parentheses)[https://osu.ppy.sh/home] and [[also a rogue wiki link]]", 2, expectedActions: new[] { LinkAction.External, LinkAction.External });
+            addMessageWithChecks("(Old link format with escaped (and \\( paired) parentheses)[https://dev.ppy.sh/home] and [[also a rogue wiki link]]", 2, expectedActions: new[] { LinkAction.External, LinkAction.External });
             // note that there's 0 links here (they get removed if a channel is not found)
             addMessageWithChecks("#lobby or #osu would be blue (and work) in the ChatDisplay test (when a proper ChatOverlay is present).");
             addMessageWithChecks("I am important!", 0, false, true);
             addMessageWithChecks("feels important", 0, true, true);
-            addMessageWithChecks("likes to post this [https://osu.ppy.sh/home link].", 1, true, true, expectedActions: LinkAction.External);
+            addMessageWithChecks("likes to post this [https://dev.ppy.sh/home link].", 1, true, true, expectedActions: LinkAction.External);
             addMessageWithChecks("Join my multiplayer game osump://12346.", 1, expectedActions: LinkAction.JoinMultiplayerMatch);
             addMessageWithChecks("Join my [multiplayer game](osump://12346).", 1, expectedActions: LinkAction.JoinMultiplayerMatch);
             addMessageWithChecks("Join my [#english](osu://chan/#english).", 1, expectedActions: LinkAction.OpenChannel);
@@ -136,9 +136,9 @@ namespace osu.Game.Tests.Visual.Online
             int echoCounter = 0;
 
             addEchoWithWait("sent!", "received!");
-            addEchoWithWait("https://osu.ppy.sh/home", null, 500);
+            addEchoWithWait("https://dev.ppy.sh/home", null, 500);
-            addEchoWithWait("[https://osu.ppy.sh/forum let's try multiple words too!]");
+            addEchoWithWait("[https://dev.ppy.sh/forum let's try multiple words too!]");
-            addEchoWithWait("(long loading times! clickable while loading?)[https://osu.ppy.sh/home]", null, 5000);
+            addEchoWithWait("(long loading times! clickable while loading?)[https://dev.ppy.sh/home]", null, 5000);
 
             void addEchoWithWait(string text, string completeText = null, double delay = 250)
             {

osu.Game.Tests/osu.Game.Tests.csproj

@@ -4,7 +4,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="DeepEqual" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
     <PackageReference Include="Moq" Version="4.16.0" />

osu.Game.Tournament.Tests/TournamentTestBrowser.cs

@@ -13,6 +13,8 @@ namespace osu.Game.Tournament.Tests
         {
             base.LoadComplete();
 
+            BracketLoadTask.ContinueWith(_ => Schedule(() =>
+            {
                 LoadComponentAsync(new Background("Menu/menu-background-0")
                 {
                     Colour = OsuColour.Gray(0.5f),
@@ -22,6 +24,7 @@ namespace osu.Game.Tournament.Tests
                 // Have to construct this here, rather than in the constructor, because
                 // we depend on some dependencies to be loaded within OsuGameBase.load().
                 Add(new TestBrowser());
+            }));
         }
     }
 }

osu.Game.Tournament.Tests/TournamentTestScene.cs

@@ -2,6 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using System.Linq;
+using System.Threading;
 using osu.Framework.Allocation;
 using osu.Framework.Platform;
 using osu.Framework.Testing;
@@ -153,14 +154,23 @@ namespace osu.Game.Tournament.Tests
             private TestSceneTestRunner.TestRunner runner;
 
             protected override void LoadAsyncComplete()
+            {
+                BracketLoadTask.ContinueWith(_ => Schedule(() =>
                 {
                     // this has to be run here rather than LoadComplete because
                     // TestScene.cs is checking the IsLoaded state (on another thread) and expects
                     // the runner to be loaded at that point.
                     Add(runner = new TestSceneTestRunner.TestRunner());
+                }));
             }
 
-            public void RunTestBlocking(TestScene test) => runner.RunTestBlocking(test);
+            public void RunTestBlocking(TestScene test)
+            {
+                while (runner?.IsLoaded != true && Host.ExecutionState == ExecutionState.Running)
+                    Thread.Sleep(10);
+
+                runner?.RunTestBlocking(test);
+            }
         }
     }
 }

osu.Game.Tournament.Tests/osu.Game.Tournament.Tests.csproj

@@ -6,7 +6,7 @@
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.8.3" />
-    <PackageReference Include="NUnit" Version="3.12.0" />
+    <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
   </ItemGroup>
   <PropertyGroup Label="Project">

osu.Game.Tournament/TournamentGame.cs

@@ -13,6 +13,7 @@ using osu.Framework.Graphics.Colour;
 using osu.Game.Graphics.Cursor;
 using osu.Game.Tournament.Models;
 using osu.Game.Graphics;
+using osu.Game.Graphics.UserInterface;
 using osuTK;
 using osuTK.Graphics;
 
@@ -32,25 +33,24 @@ namespace osu.Game.Tournament
         private Drawable heightWarning;
         private Bindable<Size> windowSize;
         private Bindable<WindowMode> windowMode;
+        private LoadingSpinner loadingSpinner;
 
         [BackgroundDependencyLoader]
         private void load(FrameworkConfigManager frameworkConfig)
         {
             windowSize = frameworkConfig.GetBindable<Size>(FrameworkSetting.WindowedSize);
-            windowSize.BindValueChanged(size => ScheduleAfterChildren(() =>
-            {
-                var minWidth = (int)(size.NewValue.Height / 768f * TournamentSceneManager.REQUIRED_WIDTH) - 1;
-
-                heightWarning.Alpha = size.NewValue.Width < minWidth ? 1 : 0;
-            }), true);
-
             windowMode = frameworkConfig.GetBindable<WindowMode>(FrameworkSetting.WindowMode);
-            windowMode.BindValueChanged(mode => ScheduleAfterChildren(() =>
-            {
-                windowMode.Value = WindowMode.Windowed;
-            }), true);
 
-            AddRange(new[]
+            Add(loadingSpinner = new LoadingSpinner(true, true)
+            {
+                Anchor = Anchor.BottomRight,
+                Origin = Anchor.BottomRight,
+                Margin = new MarginPadding(40),
+            });
+
+            loadingSpinner.Show();
+
+            BracketLoadTask.ContinueWith(_ => LoadComponentsAsync(new[]
             {
                 new Container
                 {
@@ -93,7 +93,24 @@ namespace osu.Game.Tournament
                     RelativeSizeAxes = Axes.Both,
                     Child = new TournamentSceneManager()
                 }
-            });
+            }, drawables =>
+            {
+                loadingSpinner.Hide();
+                loadingSpinner.Expire();
+
+                AddRange(drawables);
+
+                windowSize.BindValueChanged(size => ScheduleAfterChildren(() =>
+                {
+                    var minWidth = (int)(size.NewValue.Height / 768f * TournamentSceneManager.REQUIRED_WIDTH) - 1;
+                    heightWarning.Alpha = size.NewValue.Width < minWidth ? 1 : 0;
+                }), true);
+
+                windowMode.BindValueChanged(mode => ScheduleAfterChildren(() =>
+                {
+                    windowMode.Value = WindowMode.Windowed;
+                }), true);
+            }));
         }
     }
 }

osu.Game.Tournament/TournamentGameBase.cs

@@ -4,6 +4,7 @@
 using System;
 using System.IO;
 using System.Linq;
+using System.Threading.Tasks;
 using Newtonsoft.Json;
 using osu.Framework.Allocation;
 using osu.Framework.Graphics.Textures;
@@ -29,6 +30,10 @@ namespace osu.Game.Tournament
         private DependencyContainer dependencies;
         private FileBasedIPC ipc;
 
+        protected Task BracketLoadTask => taskCompletionSource.Task;
+
+        private readonly TaskCompletionSource<bool> taskCompletionSource = new TaskCompletionSource<bool>();
+
         protected override IReadOnlyDependencyContainer CreateChildDependencies(IReadOnlyDependencyContainer parent)
         {
             return dependencies = new DependencyContainer(base.CreateChildDependencies(parent));
@@ -46,14 +51,9 @@ namespace osu.Game.Tournament
 
             Textures.AddStore(new TextureLoaderStore(new StorageBackedResourceStore(storage)));
 
-            readBracket();
-
-            ladder.CurrentMatch.Value = ladder.Matches.FirstOrDefault(p => p.Current.Value);
-
             dependencies.CacheAs(new StableInfo(storage));
 
-            dependencies.CacheAs<MatchIPCInfo>(ipc = new FileBasedIPC());
+            Task.Run(readBracket);
-            Add(ipc);
         }
 
         private void readBracket()
@@ -68,10 +68,6 @@ namespace osu.Game.Tournament
             ladder ??= new LadderInfo();
             ladder.Ruleset.Value ??= RulesetStore.AvailableRulesets.First();
 
-            Ruleset.BindTo(ladder.Ruleset);
-
-            dependencies.Cache(ladder);
-
             bool addedInfo = false;
 
             // assign teams
@@ -127,6 +123,19 @@ namespace osu.Game.Tournament
 
             if (addedInfo)
                 SaveChanges();
+
+            ladder.CurrentMatch.Value = ladder.Matches.FirstOrDefault(p => p.Current.Value);
+
+            Schedule(() =>
+            {
+                Ruleset.BindTo(ladder.Ruleset);
+
+                dependencies.Cache(ladder);
+                dependencies.CacheAs<MatchIPCInfo>(ipc = new FileBasedIPC());
+                Add(ipc);
+
+                taskCompletionSource.SetResult(true);
+            });
         }
 
         /// <summary>

osu.Game/Beatmaps/BeatmapManager.cs

@@ -64,7 +64,9 @@ namespace osu.Game.Beatmaps
 
         protected override string[] HashableFileTypes => new[] { ".osu" };
 
-        protected override string ImportFromStablePath => "Songs";
+        protected override string ImportFromStablePath => ".";
+
+        protected override Storage PrepareStableStorage(StableStorage stableStorage) => stableStorage.GetSongStorage();
 
         private readonly RulesetStore rulesets;
         private readonly BeatmapStore beatmaps;

osu.Game/Beatmaps/Drawables/UpdateableBeatmapBackgroundSprite.cs

@@ -34,8 +34,8 @@ namespace osu.Game.Beatmaps.Drawables
         /// </summary>
         protected virtual double UnloadDelay => 10000;
 
-        protected override DelayedLoadWrapper CreateDelayedLoadWrapper(Func<Drawable> createContentFunc, double timeBeforeLoad)
+        protected override DelayedLoadWrapper CreateDelayedLoadWrapper(Func<Drawable> createContentFunc, double timeBeforeLoad) =>
-            => new DelayedLoadUnloadWrapper(createContentFunc, timeBeforeLoad, UnloadDelay);
+            new DelayedLoadUnloadWrapper(createContentFunc, timeBeforeLoad, UnloadDelay) { RelativeSizeAxes = Axes.Both };
 
         protected override double TransformDuration => 400;
 

osu.Game/Configuration/ModSettingChangeTracker.cs

@@ -0,0 +1,52 @@
+// 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 osu.Game.Overlays.Settings;
+using osu.Game.Rulesets.Mods;
+
+namespace osu.Game.Configuration
+{
+    /// <summary>
+    /// A helper class for tracking changes to the settings of a set of <see cref="Mod"/>s.
+    /// </summary>
+    /// <remarks>
+    /// Ensure to dispose when usage is finished.
+    /// </remarks>
+    public class ModSettingChangeTracker : IDisposable
+    {
+        /// <summary>
+        /// Notifies that the setting of a <see cref="Mod"/> has changed.
+        /// </summary>
+        public Action<Mod> SettingChanged;
+
+        private readonly List<ISettingsItem> settings = new List<ISettingsItem>();
+
+        /// <summary>
+        /// Creates a new <see cref="ModSettingChangeTracker"/> for a set of <see cref="Mod"/>s.
+        /// </summary>
+        /// <param name="mods">The set of <see cref="Mod"/>s whose settings need to be tracked.</param>
+        public ModSettingChangeTracker(IEnumerable<Mod> mods)
+        {
+            foreach (var mod in mods)
+            {
+                foreach (var setting in mod.CreateSettingsControls().OfType<ISettingsItem>())
+                {
+                    setting.SettingChanged += () => SettingChanged?.Invoke(mod);
+                    settings.Add(setting);
+                }
+            }
+        }
+
+        public void Dispose()
+        {
+            SettingChanged = null;
+
+            foreach (var r in settings)
+                r.Dispose();
+            settings.Clear();
+        }
+    }
+}

osu.Game/Configuration/SettingSourceAttribute.cs

@@ -57,6 +57,7 @@ namespace osu.Game.Configuration
                         yield return new SettingsSlider<float>
                         {
                             LabelText = attr.Label,
+                            TooltipText = attr.Description,
                             Current = bNumber,
                             KeyboardStep = 0.1f,
                         };
@@ -67,6 +68,7 @@ namespace osu.Game.Configuration
                         yield return new SettingsSlider<double>
                         {
                             LabelText = attr.Label,
+                            TooltipText = attr.Description,
                             Current = bNumber,
                             KeyboardStep = 0.1f,
                         };
@@ -77,6 +79,7 @@ namespace osu.Game.Configuration
                         yield return new SettingsSlider<int>
                         {
                             LabelText = attr.Label,
+                            TooltipText = attr.Description,
                             Current = bNumber
                         };
 
@@ -86,6 +89,7 @@ namespace osu.Game.Configuration
                         yield return new SettingsCheckbox
                         {
                             LabelText = attr.Label,
+                            TooltipText = attr.Description,
                             Current = bBool
                         };
 
@@ -95,6 +99,7 @@ namespace osu.Game.Configuration
                         yield return new SettingsTextBox
                         {
                             LabelText = attr.Label,
+                            TooltipText = attr.Description,
                             Current = bString
                         };
 
@@ -105,6 +110,7 @@ namespace osu.Game.Configuration
                         var dropdown = (Drawable)Activator.CreateInstance(dropdownType);
 
                         dropdownType.GetProperty(nameof(SettingsDropdown<object>.LabelText))?.SetValue(dropdown, attr.Label);
+                        dropdownType.GetProperty(nameof(SettingsDropdown<object>.TooltipText))?.SetValue(dropdown, attr.Description);
                         dropdownType.GetProperty(nameof(SettingsDropdown<object>.Current))?.SetValue(dropdown, bindable);
 
                         yield return dropdown;

osu.Game/Database/ArchiveModelManager.cs

@@ -625,7 +625,7 @@ namespace osu.Game.Database
         /// <summary>
         /// Set a storage with access to an osu-stable install for import purposes.
         /// </summary>
-        public Func<Storage> GetStableStorage { private get; set; }
+        public Func<StableStorage> GetStableStorage { private get; set; }
 
         /// <summary>
         /// Denotes whether an osu-stable installation is present to perform automated imports from.
@@ -638,9 +638,10 @@ namespace osu.Game.Database
         protected virtual string ImportFromStablePath => null;
 
         /// <summary>
-        /// Select paths to import from stable. Default implementation iterates all directories in <see cref="ImportFromStablePath"/>.
+        /// Select paths to import from stable where all paths should be absolute. Default implementation iterates all directories in <see cref="ImportFromStablePath"/>.
         /// </summary>
-        protected virtual IEnumerable<string> GetStableImportPaths(Storage stableStoage) => stableStoage.GetDirectories(ImportFromStablePath);
+        protected virtual IEnumerable<string> GetStableImportPaths(Storage storage) => storage.GetDirectories(ImportFromStablePath)
+                                                                                              .Select(path => storage.GetFullPath(path));
 
         /// <summary>
         /// Whether this specified path should be removed after successful import.
@@ -654,24 +655,33 @@ namespace osu.Game.Database
         /// </summary>
         public Task ImportFromStableAsync()
         {
-            var stable = GetStableStorage?.Invoke();
+            var stableStorage = GetStableStorage?.Invoke();
 
-            if (stable == null)
+            if (stableStorage == null)
             {
                 Logger.Log("No osu!stable installation available!", LoggingTarget.Information, LogLevel.Error);
                 return Task.CompletedTask;
             }
 
-            if (!stable.ExistsDirectory(ImportFromStablePath))
+            var storage = PrepareStableStorage(stableStorage);
+
+            if (!storage.ExistsDirectory(ImportFromStablePath))
             {
                 // This handles situations like when the user does not have a Skins folder
                 Logger.Log($"No {ImportFromStablePath} folder available in osu!stable installation", LoggingTarget.Information, LogLevel.Error);
                 return Task.CompletedTask;
             }
 
-            return Task.Run(async () => await Import(GetStableImportPaths(GetStableStorage()).Select(f => stable.GetFullPath(f)).ToArray()));
+            return Task.Run(async () => await Import(GetStableImportPaths(storage).ToArray()));
         }
 
+        /// <summary>
+        /// Run any required traversal operations on the stable storage location before performing operations.
+        /// </summary>
+        /// <param name="stableStorage">The stable storage.</param>
+        /// <returns>The usable storage. Return the unchanged <paramref name="stableStorage"/> if no traversal is required.</returns>
+        protected virtual Storage PrepareStableStorage(StableStorage stableStorage) => stableStorage;
+
         #endregion
 
         /// <summary>

osu.Game/Graphics/Containers/LinkFlowContainer.cs

@@ -38,7 +38,12 @@ namespace osu.Game.Graphics.Containers
             foreach (var link in links)
             {
                 AddText(text[previousLinkEnd..link.Index]);
-                AddLink(text.Substring(link.Index, link.Length), link.Action, link.Argument ?? link.Url);
+
+                string displayText = text.Substring(link.Index, link.Length);
+                string linkArgument = link.Argument ?? link.Url;
+                string tooltip = displayText == link.Url ? null : link.Url;
+
+                AddLink(displayText, link.Action, linkArgument, tooltip);
                 previousLinkEnd = link.Index + link.Length;
             }
 
@@ -52,7 +57,7 @@ namespace osu.Game.Graphics.Containers
             => createLink(AddText(text, creationParameters), new LinkDetails(LinkAction.Custom, null), tooltipText, action);
 
         public void AddLink(string text, LinkAction action, string argument, string tooltipText = null, Action<SpriteText> creationParameters = null)
-            => createLink(AddText(text, creationParameters), new LinkDetails(action, argument), null);
+            => createLink(AddText(text, creationParameters), new LinkDetails(action, argument), tooltipText);
 
         public void AddLink(IEnumerable<SpriteText> text, LinkAction action = LinkAction.External, string linkArgument = null, string tooltipText = null)
         {

osu.Game/Graphics/Containers/OsuFocusedOverlayContainer.cs

@@ -18,8 +18,8 @@ namespace osu.Game.Graphics.Containers
     [Cached(typeof(IPreviewTrackOwner))]
     public abstract class OsuFocusedOverlayContainer : FocusedOverlayContainer, IPreviewTrackOwner, IKeyBindingHandler<GlobalAction>
     {
-        private SampleChannel samplePopIn;
+        private Sample samplePopIn;
-        private SampleChannel samplePopOut;
+        private Sample samplePopOut;
         protected virtual string PopInSampleName => "UI/overlay-pop-in";
         protected virtual string PopOutSampleName => "UI/overlay-pop-out";
 

osu.Game/Graphics/ScreenshotManager.cs

@@ -44,7 +44,7 @@ namespace osu.Game.Graphics
         [Resolved]
         private NotificationOverlay notificationOverlay { get; set; }
 
-        private SampleChannel shutter;
+        private Sample shutter;
 
         [BackgroundDependencyLoader]
         private void load(OsuConfigManager config, Storage storage, AudioManager audio)

osu.Game/Graphics/UserInterface/DrawableOsuMenuItem.cs

@@ -22,8 +22,8 @@ namespace osu.Game.Graphics.UserInterface
         private const int text_size = 17;
         private const int transition_length = 80;
 
-        private SampleChannel sampleClick;
+        private Sample sampleClick;
-        private SampleChannel sampleHover;
+        private Sample sampleHover;
 
         private TextContainer text;
 

osu.Game/Graphics/UserInterface/HoverClickSounds.cs

@@ -17,7 +17,7 @@ namespace osu.Game.Graphics.UserInterface
     /// </summary>
     public class HoverClickSounds : HoverSounds
     {
-        private SampleChannel sampleClick;
+        private Sample sampleClick;
         private readonly MouseButton[] buttons;
 
         /// <summary>

osu.Game/Graphics/UserInterface/HoverSampleDebounceComponent.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 osu.Framework.Allocation;
+using osu.Framework.Audio;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Input.Events;
+using osu.Game.Configuration;
+
+namespace osu.Game.Graphics.UserInterface
+{
+    /// <summary>
+    /// Handles debouncing hover sounds at a global level to ensure the effects are not overwhelming.
+    /// </summary>
+    public abstract class HoverSampleDebounceComponent : CompositeDrawable
+    {
+        /// <summary>
+        /// Length of debounce for hover sound playback, in milliseconds.
+        /// </summary>
+        public double HoverDebounceTime { get; } = 20;
+
+        private Bindable<double?> lastPlaybackTime;
+
+        [BackgroundDependencyLoader]
+        private void load(AudioManager audio, SessionStatics statics)
+        {
+            lastPlaybackTime = statics.GetBindable<double?>(Static.LastHoverSoundPlaybackTime);
+        }
+
+        protected override bool OnHover(HoverEvent e)
+        {
+            // hover sounds shouldn't be played during scroll operations.
+            if (e.HasAnyButtonPressed)
+                return false;
+
+            bool enoughTimePassedSinceLastPlayback = !lastPlaybackTime.Value.HasValue || Time.Current - lastPlaybackTime.Value >= HoverDebounceTime;
+
+            if (enoughTimePassedSinceLastPlayback)
+            {
+                PlayHoverSample();
+                lastPlaybackTime.Value = Time.Current;
+            }
+
+            return false;
+        }
+
+        public abstract void PlayHoverSample();
+    }
+}

osu.Game/Graphics/UserInterface/HoverSounds.cs

@@ -5,11 +5,8 @@ using System.ComponentModel;
 using osu.Framework.Allocation;
 using osu.Framework.Audio;
 using osu.Framework.Audio.Sample;
-using osu.Framework.Bindables;
 using osu.Framework.Extensions;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Framework.Input.Events;
 using osu.Game.Configuration;
 using osu.Framework.Utils;
 
@@ -19,19 +16,12 @@ namespace osu.Game.Graphics.UserInterface
     /// Adds hover sounds to a drawable.
     /// Does not draw anything.
     /// </summary>
-    public class HoverSounds : CompositeDrawable
+    public class HoverSounds : HoverSampleDebounceComponent
     {
-        private SampleChannel sampleHover;
+        private Sample sampleHover;
-
-        /// <summary>
-        /// Length of debounce for hover sound playback, in milliseconds.
-        /// </summary>
-        public double HoverDebounceTime { get; } = 20;
 
         protected readonly HoverSampleSet SampleSet;
 
-        private Bindable<double?> lastPlaybackTime;
-
         public HoverSounds(HoverSampleSet sampleSet = HoverSampleSet.Normal)
         {
             SampleSet = sampleSet;
@@ -41,27 +31,13 @@ namespace osu.Game.Graphics.UserInterface
         [BackgroundDependencyLoader]
         private void load(AudioManager audio, SessionStatics statics)
         {
-            lastPlaybackTime = statics.GetBindable<double?>(Static.LastHoverSoundPlaybackTime);
-
             sampleHover = audio.Samples.Get($@"UI/generic-hover{SampleSet.GetDescription()}");
         }
 
-        protected override bool OnHover(HoverEvent e)
+        public override void PlayHoverSample()
-        {
-            if (sampleHover == null)
-                return false;
-
-            bool enoughTimePassedSinceLastPlayback = !lastPlaybackTime.Value.HasValue || Time.Current - lastPlaybackTime.Value >= HoverDebounceTime;
-
-            if (enoughTimePassedSinceLastPlayback)
         {
             sampleHover.Frequency.Value = 0.96 + RNG.NextDouble(0.08);
             sampleHover.Play();
-
-                lastPlaybackTime.Value = Time.Current;
-            }
-
-            return false;
         }
     }
 

osu.Game/Graphics/UserInterface/OsuCheckbox.cs

@@ -46,8 +46,8 @@ namespace osu.Game.Graphics.UserInterface
         protected readonly Nub Nub;
 
         private readonly OsuTextFlowContainer labelText;
-        private SampleChannel sampleChecked;
+        private Sample sampleChecked;
-        private SampleChannel sampleUnchecked;
+        private Sample sampleUnchecked;
 
         public OsuCheckbox(bool nubOnRight = true)
         {
@@ -64,7 +64,7 @@ namespace osu.Game.Graphics.UserInterface
                     RelativeSizeAxes = Axes.X,
                 },
                 Nub = new Nub(),
-                new HoverClickSounds()
+                new HoverSounds()
             };
 
             if (nubOnRight)

osu.Game/Graphics/UserInterface/OsuSliderBar.cs

@@ -25,7 +25,7 @@ namespace osu.Game.Graphics.UserInterface
         /// </summary>
         private const int max_decimal_digits = 5;
 
-        private SampleChannel sample;
+        private Sample sample;
         private double lastSampleTime;
         private T lastSampleValue;
 
@@ -155,16 +155,15 @@ namespace osu.Game.Graphics.UserInterface
                 return;
 
             lastSampleValue = value;
-
             lastSampleTime = Clock.CurrentTime;
-            sample.Frequency.Value = 1 + NormalizedValue * 0.2f;
 
+            var channel = sample.Play();
+
+            channel.Frequency.Value = 1 + NormalizedValue * 0.2f;
             if (NormalizedValue == 0)
-                sample.Frequency.Value -= 0.4f;
+                channel.Frequency.Value -= 0.4f;
             else if (NormalizedValue == 1)
-                sample.Frequency.Value += 0.4f;
+                channel.Frequency.Value += 0.4f;
-
-            sample.Play();
         }
 
         private void updateTooltipText(T value)

osu.Game/Graphics/UserInterface/OsuTextBox.cs

@@ -23,11 +23,11 @@ namespace osu.Game.Graphics.UserInterface
 {
     public class OsuTextBox : BasicTextBox
     {
-        private readonly SampleChannel[] textAddedSamples = new SampleChannel[4];
+        private readonly Sample[] textAddedSamples = new Sample[4];
-        private SampleChannel capsTextAddedSample;
+        private Sample capsTextAddedSample;
-        private SampleChannel textRemovedSample;
+        private Sample textRemovedSample;
-        private SampleChannel textCommittedSample;
+        private Sample textCommittedSample;
-        private SampleChannel caretMovedSample;
+        private Sample caretMovedSample;
 
         /// <summary>
         /// Whether to allow playing a different samples based on the type of character.

osu.Game/IO/StableStorage.cs

@@ -0,0 +1,62 @@
+// 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.IO;
+using System.Linq;
+using osu.Framework.Platform;
+
+namespace osu.Game.IO
+{
+    /// <summary>
+    /// A storage pointing to an osu-stable installation.
+    /// Provides methods for handling installations with a custom Song folder location.
+    /// </summary>
+    public class StableStorage : DesktopStorage
+    {
+        private const string stable_default_songs_path = "Songs";
+
+        private readonly DesktopGameHost host;
+        private readonly Lazy<string> songsPath;
+
+        public StableStorage(string path, DesktopGameHost host)
+            : base(path, host)
+        {
+            this.host = host;
+
+            songsPath = new Lazy<string>(locateSongsDirectory);
+        }
+
+        /// <summary>
+        /// Returns a <see cref="Storage"/> pointing to the osu-stable Songs directory.
+        /// </summary>
+        public Storage GetSongStorage() => new DesktopStorage(songsPath.Value, host);
+
+        private string locateSongsDirectory()
+        {
+            var configFile = GetFiles(".", $"osu!.{Environment.UserName}.cfg").SingleOrDefault();
+
+            if (configFile != null)
+            {
+                using (var stream = GetStream(configFile))
+                using (var textReader = new StreamReader(stream))
+                {
+                    string line;
+
+                    while ((line = textReader.ReadLine()) != null)
+                    {
+                        if (!line.StartsWith("BeatmapDirectory", StringComparison.OrdinalIgnoreCase)) continue;
+
+                        var customDirectory = line.Split('=').LastOrDefault()?.Trim();
+                        if (customDirectory != null && Path.IsPathFullyQualified(customDirectory))
+                            return customDirectory;
+
+                        break;
+                    }
+                }
+            }
+
+            return GetFullPath(stable_default_songs_path);
+        }
+    }
+}

osu.Game/Online/API/APIAccess.cs

@@ -25,6 +25,8 @@ namespace osu.Game.Online.API
     {
         private readonly OsuConfigManager config;
 
+        private readonly string versionHash;
+
         private readonly OAuth authentication;
 
         private readonly Queue<APIRequest> queue = new Queue<APIRequest>();
@@ -56,9 +58,10 @@ namespace osu.Game.Online.API
 
         private readonly Logger log;
 
-        public APIAccess(OsuConfigManager config, EndpointConfiguration endpointConfiguration)
+        public APIAccess(OsuConfigManager config, EndpointConfiguration endpointConfiguration, string versionHash)
         {
             this.config = config;
+            this.versionHash = versionHash;
 
             APIEndpointUrl = endpointConfiguration.APIEndpointUrl;
             WebsiteRootUrl = endpointConfiguration.WebsiteRootUrl;
@@ -243,6 +246,8 @@ namespace osu.Game.Online.API
             this.password = password;
         }
 
+        public IHubClientConnector GetHubConnector(string clientName, string endpoint) => new HubClientConnector(clientName, endpoint, this, versionHash);
+
         public RegistrationRequest.RegistrationRequestErrors CreateAccount(string email, string username, string password)
         {
             Debug.Assert(State.Value == APIState.Offline);

osu.Game/Online/API/DummyAPIAccess.cs

@@ -83,6 +83,8 @@ namespace osu.Game.Online.API
             state.Value = APIState.Offline;
         }
 
+        public IHubClientConnector GetHubConnector(string clientName, string endpoint) => null;
+
         public RegistrationRequest.RegistrationRequestErrors CreateAccount(string email, string username, string password)
         {
             Thread.Sleep(200);

osu.Game/Online/API/IAPIProvider.cs

@@ -1,6 +1,8 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+#nullable enable
+
 using System.Threading.Tasks;
 using osu.Framework.Bindables;
 using osu.Game.Users;
@@ -95,6 +97,13 @@ namespace osu.Game.Online.API
         /// </summary>
         void Logout();
 
+        /// <summary>
+        /// Constructs a new <see cref="IHubClientConnector"/>. May be null if not supported.
+        /// </summary>
+        /// <param name="clientName">The name of the client this connector connects for, used for logging.</param>
+        /// <param name="endpoint">The endpoint to the hub.</param>
+        IHubClientConnector? GetHubConnector(string clientName, string endpoint);
+
         /// <summary>
         /// Create a new user account. This is a blocking operation.
         /// </summary>
@@ -102,6 +111,6 @@ namespace osu.Game.Online.API
         /// <param name="username">The username to create the account with.</param>
         /// <param name="password">The password to create the account with.</param>
         /// <returns>Any errors encoutnered during account creation.</returns>
-        RegistrationRequest.RegistrationRequestErrors CreateAccount(string email, string username, string password);
+        RegistrationRequest.RegistrationRequestErrors? CreateAccount(string email, string username, string password);
     }
 }

osu.Game/Online/Chat/MessageFormatter.cs

@@ -49,6 +49,18 @@ namespace osu.Game.Online.Chat
         // Unicode emojis
         private static readonly Regex emoji_regex = new Regex(@"(\uD83D[\uDC00-\uDE4F])");
 
+        /// <summary>
+        /// The root URL for the website, used for chat link matching.
+        /// </summary>
+        public static string WebsiteRootUrl
+        {
+            set => websiteRootUrl = value
+                                    .Trim('/') // trim potential trailing slash/
+                                    .Split('/').Last(); // only keep domain name, ignoring protocol.
+        }
+
+        private static string websiteRootUrl = "osu.ppy.sh";
+
         private static void handleMatches(Regex regex, string display, string link, MessageFormatterResult result, int startIndex = 0, LinkAction? linkActionOverride = null, char[] escapeChars = null)
         {
             int captureOffset = 0;
@@ -119,22 +131,42 @@ namespace osu.Game.Online.Chat
                 case "http":
                 case "https":
                     // length > 3 since all these links need another argument to work
-                    if (args.Length > 3 && args[1] == "osu.ppy.sh")
+                    if (args.Length > 3 && args[1].EndsWith(websiteRootUrl, StringComparison.OrdinalIgnoreCase))
                     {
+                        var mainArg = args[3];
+
                         switch (args[2])
                         {
+                            // old site only
                             case "b":
                             case "beatmaps":
-                                return new LinkDetails(LinkAction.OpenBeatmap, args[3]);
+                            {
+                                string trimmed = mainArg.Split('?').First();
+                                if (int.TryParse(trimmed, out var id))
+                                    return new LinkDetails(LinkAction.OpenBeatmap, id.ToString());
+
+                                break;
+                            }
 
                             case "s":
                             case "beatmapsets":
                             case "d":
-                                return new LinkDetails(LinkAction.OpenBeatmapSet, args[3]);
+                            {
+                                if (args.Length > 4 && int.TryParse(args[4], out var id))
+                                    // https://osu.ppy.sh/beatmapsets/1154158#osu/2768184
+                                    return new LinkDetails(LinkAction.OpenBeatmap, id.ToString());
+
+                                // https://osu.ppy.sh/beatmapsets/1154158#whatever
+                                string trimmed = mainArg.Split('#').First();
+                                if (int.TryParse(trimmed, out id))
+                                    return new LinkDetails(LinkAction.OpenBeatmapSet, id.ToString());
+
+                                break;
+                            }
 
                             case "u":
                             case "users":
-                                return new LinkDetails(LinkAction.OpenUserProfile, args[3]);
+                                return new LinkDetails(LinkAction.OpenUserProfile, mainArg);
                         }
                     }
 
@@ -183,10 +215,9 @@ namespace osu.Game.Online.Chat
 
                 case "osump":
                     return new LinkDetails(LinkAction.JoinMultiplayerMatch, args[1]);
-
-                default:
-                    return new LinkDetails(LinkAction.External, null);
             }
+
+            return new LinkDetails(LinkAction.External, null);
         }
 
         private static MessageFormatterResult format(string toFormat, int startIndex = 0, int space = 3)
@@ -259,8 +290,9 @@ namespace osu.Game.Online.Chat
 
     public class LinkDetails
     {
-        public LinkAction Action;
+        public readonly LinkAction Action;
-        public string Argument;
+
+        public readonly string Argument;
 
         public LinkDetails(LinkAction action, string argument)
         {

osu.Game/Online/HubClientConnector.cs

@@ -0,0 +1,208 @@
+// 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 enable
+
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.SignalR.Client;
+using Microsoft.Extensions.DependencyInjection;
+using Newtonsoft.Json;
+using osu.Framework;
+using osu.Framework.Bindables;
+using osu.Framework.Logging;
+using osu.Game.Online.API;
+
+namespace osu.Game.Online
+{
+    public class HubClientConnector : IHubClientConnector
+    {
+        /// <summary>
+        /// Invoked whenever a new hub connection is built, to configure it before it's started.
+        /// </summary>
+        public Action<HubConnection>? ConfigureConnection { get; set; }
+
+        private readonly string clientName;
+        private readonly string endpoint;
+        private readonly string versionHash;
+        private readonly IAPIProvider api;
+
+        /// <summary>
+        /// The current connection opened by this connector.
+        /// </summary>
+        public HubConnection? CurrentConnection { get; private set; }
+
+        /// <summary>
+        /// Whether this is connected to the hub, use <see cref="CurrentConnection"/> to access the connection, if this is <c>true</c>.
+        /// </summary>
+        public IBindable<bool> IsConnected => isConnected;
+
+        private readonly Bindable<bool> isConnected = new Bindable<bool>();
+        private readonly SemaphoreSlim connectionLock = new SemaphoreSlim(1);
+        private CancellationTokenSource connectCancelSource = new CancellationTokenSource();
+
+        private readonly IBindable<APIState> apiState = new Bindable<APIState>();
+
+        /// <summary>
+        /// Constructs a new <see cref="HubClientConnector"/>.
+        /// </summary>
+        /// <param name="clientName">The name of the client this connector connects for, used for logging.</param>
+        /// <param name="endpoint">The endpoint to the hub.</param>
+        /// <param name="api"> An API provider used to react to connection state changes.</param>
+        /// <param name="versionHash">The hash representing the current game version, used for verification purposes.</param>
+        public HubClientConnector(string clientName, string endpoint, IAPIProvider api, string versionHash)
+        {
+            this.clientName = clientName;
+            this.endpoint = endpoint;
+            this.api = api;
+            this.versionHash = versionHash;
+
+            apiState.BindTo(api.State);
+            apiState.BindValueChanged(state =>
+            {
+                switch (state.NewValue)
+                {
+                    case APIState.Failing:
+                    case APIState.Offline:
+                        Task.Run(() => disconnect(true));
+                        break;
+
+                    case APIState.Online:
+                        Task.Run(connect);
+                        break;
+                }
+            }, true);
+        }
+
+        private async Task connect()
+        {
+            cancelExistingConnect();
+
+            if (!await connectionLock.WaitAsync(10000))
+                throw new TimeoutException("Could not obtain a lock to connect. A previous attempt is likely stuck.");
+
+            try
+            {
+                while (apiState.Value == APIState.Online)
+                {
+                    // ensure any previous connection was disposed.
+                    // this will also create a new cancellation token source.
+                    await disconnect(false);
+
+                    // this token will be valid for the scope of this connection.
+                    // if cancelled, we can be sure that a disconnect or reconnect is handled elsewhere.
+                    var cancellationToken = connectCancelSource.Token;
+
+                    cancellationToken.ThrowIfCancellationRequested();
+
+                    Logger.Log($"{clientName} connecting...", LoggingTarget.Network);
+
+                    try
+                    {
+                        // importantly, rebuild the connection each attempt to get an updated access token.
+                        CurrentConnection = buildConnection(cancellationToken);
+
+                        await CurrentConnection.StartAsync(cancellationToken);
+
+                        Logger.Log($"{clientName} connected!", LoggingTarget.Network);
+                        isConnected.Value = true;
+                        return;
+                    }
+                    catch (OperationCanceledException)
+                    {
+                        //connection process was cancelled.
+                        throw;
+                    }
+                    catch (Exception e)
+                    {
+                        Logger.Log($"{clientName} connection error: {e}", LoggingTarget.Network);
+
+                        // retry on any failure.
+                        await Task.Delay(5000, cancellationToken);
+                    }
+                }
+            }
+            finally
+            {
+                connectionLock.Release();
+            }
+        }
+
+        private HubConnection buildConnection(CancellationToken cancellationToken)
+        {
+            var builder = new HubConnectionBuilder()
+                .WithUrl(endpoint, options =>
+                {
+                    options.Headers.Add("Authorization", $"Bearer {api.AccessToken}");
+                    options.Headers.Add("OsuVersionHash", versionHash);
+                });
+
+            if (RuntimeInfo.SupportsJIT)
+                builder.AddMessagePackProtocol();
+            else
+            {
+                // eventually we will precompile resolvers for messagepack, but this isn't working currently
+                // see https://github.com/neuecc/MessagePack-CSharp/issues/780#issuecomment-768794308.
+                builder.AddNewtonsoftJsonProtocol(options => { options.PayloadSerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; });
+            }
+
+            var newConnection = builder.Build();
+
+            ConfigureConnection?.Invoke(newConnection);
+
+            newConnection.Closed += ex => onConnectionClosed(ex, cancellationToken);
+            return newConnection;
+        }
+
+        private Task onConnectionClosed(Exception? ex, CancellationToken cancellationToken)
+        {
+            isConnected.Value = false;
+
+            Logger.Log(ex != null ? $"{clientName} lost connection: {ex}" : $"{clientName} disconnected", LoggingTarget.Network);
+
+            // make sure a disconnect wasn't triggered (and this is still the active connection).
+            if (!cancellationToken.IsCancellationRequested)
+                Task.Run(connect, default);
+
+            return Task.CompletedTask;
+        }
+
+        private async Task disconnect(bool takeLock)
+        {
+            cancelExistingConnect();
+
+            if (takeLock)
+            {
+                if (!await connectionLock.WaitAsync(10000))
+                    throw new TimeoutException("Could not obtain a lock to disconnect. A previous attempt is likely stuck.");
+            }
+
+            try
+            {
+                if (CurrentConnection != null)
+                    await CurrentConnection.DisposeAsync();
+            }
+            finally
+            {
+                CurrentConnection = null;
+                if (takeLock)
+                    connectionLock.Release();
+            }
+        }
+
+        private void cancelExistingConnect()
+        {
+            connectCancelSource.Cancel();
+            connectCancelSource = new CancellationTokenSource();
+        }
+
+        public override string ToString() => $"Connector for {clientName} ({(IsConnected.Value ? "connected" : "not connected")}";
+
+        public void Dispose()
+        {
+            apiState.UnbindAll();
+            cancelExistingConnect();
+        }
+    }
+}

osu.Game/Online/IHubClientConnector.cs

@@ -0,0 +1,34 @@
+// 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 enable
+
+using System;
+using Microsoft.AspNetCore.SignalR.Client;
+using osu.Framework.Bindables;
+using osu.Game.Online.API;
+
+namespace osu.Game.Online
+{
+    /// <summary>
+    /// A component that manages the life cycle of a connection to a SignalR Hub.
+    /// Should generally be retrieved from an <see cref="IAPIProvider"/>.
+    /// </summary>
+    public interface IHubClientConnector : IDisposable
+    {
+        /// <summary>
+        /// The current connection opened by this connector.
+        /// </summary>
+        HubConnection? CurrentConnection { get; }
+
+        /// <summary>
+        /// Whether this is connected to the hub, use <see cref="CurrentConnection"/> to access the connection, if this is <c>true</c>.
+        /// </summary>
+        IBindable<bool> IsConnected { get; }
+
+        /// <summary>
+        /// Invoked whenever a new hub connection is built, to configure it before it's started.
+        /// </summary>
+        public Action<HubConnection>? ConfigureConnection { get; set; }
+    }
+}

osu.Game/Online/Multiplayer/MultiplayerClient.cs

@@ -3,17 +3,12 @@
 
 #nullable enable
 
-using System;
 using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.SignalR.Client;
-using Microsoft.Extensions.DependencyInjection;
-using Newtonsoft.Json;
-using osu.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
-using osu.Framework.Logging;
 using osu.Game.Online.API;
 using osu.Game.Online.Rooms;
 
@@ -21,106 +16,50 @@ namespace osu.Game.Online.Multiplayer
 {
     public class MultiplayerClient : StatefulMultiplayerClient
     {
-        public override IBindable<bool> IsConnected => isConnected;
-
-        private readonly Bindable<bool> isConnected = new Bindable<bool>();
-        private readonly IBindable<APIState> apiState = new Bindable<APIState>();
-
-        private readonly SemaphoreSlim connectionLock = new SemaphoreSlim(1);
-
-        [Resolved]
-        private IAPIProvider api { get; set; } = null!;
-
-        private HubConnection? connection;
-
-        private CancellationTokenSource connectCancelSource = new CancellationTokenSource();
-
         private readonly string endpoint;
 
+        private IHubClientConnector? connector;
+
+        public override IBindable<bool> IsConnected { get; } = new BindableBool();
+
+        private HubConnection? connection => connector?.CurrentConnection;
+
         public MultiplayerClient(EndpointConfiguration endpoints)
         {
             endpoint = endpoints.MultiplayerEndpointUrl;
         }
 
         [BackgroundDependencyLoader]
-        private void load()
+        private void load(IAPIProvider api)
         {
-            apiState.BindTo(api.State);
+            connector = api.GetHubConnector(nameof(MultiplayerClient), endpoint);
-            apiState.BindValueChanged(apiStateChanged, true);
-        }
 
-        private void apiStateChanged(ValueChangedEvent<APIState> state)
+            if (connector != null)
             {
-            switch (state.NewValue)
+                connector.ConfigureConnection = connection =>
                 {
-                case APIState.Failing:
+                    // this is kind of SILLY
-                case APIState.Offline:
+                    // https://github.com/dotnet/aspnetcore/issues/15198
-                    Task.Run(() => disconnect(true));
+                    connection.On<MultiplayerRoomState>(nameof(IMultiplayerClient.RoomStateChanged), ((IMultiplayerClient)this).RoomStateChanged);
-                    break;
+                    connection.On<MultiplayerRoomUser>(nameof(IMultiplayerClient.UserJoined), ((IMultiplayerClient)this).UserJoined);
+                    connection.On<MultiplayerRoomUser>(nameof(IMultiplayerClient.UserLeft), ((IMultiplayerClient)this).UserLeft);
+                    connection.On<int>(nameof(IMultiplayerClient.HostChanged), ((IMultiplayerClient)this).HostChanged);
+                    connection.On<MultiplayerRoomSettings>(nameof(IMultiplayerClient.SettingsChanged), ((IMultiplayerClient)this).SettingsChanged);
+                    connection.On<int, MultiplayerUserState>(nameof(IMultiplayerClient.UserStateChanged), ((IMultiplayerClient)this).UserStateChanged);
+                    connection.On(nameof(IMultiplayerClient.LoadRequested), ((IMultiplayerClient)this).LoadRequested);
+                    connection.On(nameof(IMultiplayerClient.MatchStarted), ((IMultiplayerClient)this).MatchStarted);
+                    connection.On(nameof(IMultiplayerClient.ResultsReady), ((IMultiplayerClient)this).ResultsReady);
+                    connection.On<int, IEnumerable<APIMod>>(nameof(IMultiplayerClient.UserModsChanged), ((IMultiplayerClient)this).UserModsChanged);
+                    connection.On<int, BeatmapAvailability>(nameof(IMultiplayerClient.UserBeatmapAvailabilityChanged), ((IMultiplayerClient)this).UserBeatmapAvailabilityChanged);
+                };
 
-                case APIState.Online:
+                IsConnected.BindTo(connector.IsConnected);
-                    Task.Run(connect);
-                    break;
-            }
-        }
-
-        private async Task connect()
-        {
-            cancelExistingConnect();
-
-            if (!await connectionLock.WaitAsync(10000))
-                throw new TimeoutException("Could not obtain a lock to connect. A previous attempt is likely stuck.");
-
-            try
-            {
-                while (api.State.Value == APIState.Online)
-                {
-                    // ensure any previous connection was disposed.
-                    // this will also create a new cancellation token source.
-                    await disconnect(false);
-
-                    // this token will be valid for the scope of this connection.
-                    // if cancelled, we can be sure that a disconnect or reconnect is handled elsewhere.
-                    var cancellationToken = connectCancelSource.Token;
-
-                    cancellationToken.ThrowIfCancellationRequested();
-
-                    Logger.Log("Multiplayer client connecting...", LoggingTarget.Network);
-
-                    try
-                    {
-                        // importantly, rebuild the connection each attempt to get an updated access token.
-                        connection = createConnection(cancellationToken);
-
-                        await connection.StartAsync(cancellationToken);
-
-                        Logger.Log("Multiplayer client connected!", LoggingTarget.Network);
-                        isConnected.Value = true;
-                        return;
-                    }
-                    catch (OperationCanceledException)
-                    {
-                        //connection process was cancelled.
-                        throw;
-                    }
-                    catch (Exception e)
-                    {
-                        Logger.Log($"Multiplayer client connection error: {e}", LoggingTarget.Network);
-
-                        // retry on any failure.
-                        await Task.Delay(5000, cancellationToken);
-                    }
-                }
-            }
-            finally
-            {
-                connectionLock.Release();
             }
         }
 
         protected override Task<MultiplayerRoom> JoinRoom(long roomId)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.FromCanceled<MultiplayerRoom>(new CancellationToken(true));
 
             return connection.InvokeAsync<MultiplayerRoom>(nameof(IMultiplayerServer.JoinRoom), roomId);
@@ -128,7 +67,7 @@ namespace osu.Game.Online.Multiplayer
 
         protected override Task LeaveRoomInternal()
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.FromCanceled(new CancellationToken(true));
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.LeaveRoom));
@@ -136,7 +75,7 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task TransferHost(int userId)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.TransferHost), userId);
@@ -144,7 +83,7 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task ChangeSettings(MultiplayerRoomSettings settings)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.ChangeSettings), settings);
@@ -152,7 +91,7 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task ChangeState(MultiplayerUserState newState)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.ChangeState), newState);
@@ -160,7 +99,7 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task ChangeBeatmapAvailability(BeatmapAvailability newBeatmapAvailability)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.ChangeBeatmapAvailability), newBeatmapAvailability);
@@ -168,7 +107,7 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task ChangeUserMods(IEnumerable<APIMod> newMods)
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.ChangeUserMods), newMods);
@@ -176,91 +115,16 @@ namespace osu.Game.Online.Multiplayer
 
         public override Task StartMatch()
         {
-            if (!isConnected.Value)
+            if (!IsConnected.Value)
                 return Task.CompletedTask;
 
             return connection.InvokeAsync(nameof(IMultiplayerServer.StartMatch));
         }
 
-        private async Task disconnect(bool takeLock)
-        {
-            cancelExistingConnect();
-
-            if (takeLock)
-            {
-                if (!await connectionLock.WaitAsync(10000))
-                    throw new TimeoutException("Could not obtain a lock to disconnect. A previous attempt is likely stuck.");
-            }
-
-            try
-            {
-                if (connection != null)
-                    await connection.DisposeAsync();
-            }
-            finally
-            {
-                connection = null;
-                if (takeLock)
-                    connectionLock.Release();
-            }
-        }
-
-        private void cancelExistingConnect()
-        {
-            connectCancelSource.Cancel();
-            connectCancelSource = new CancellationTokenSource();
-        }
-
-        private HubConnection createConnection(CancellationToken cancellationToken)
-        {
-            var builder = new HubConnectionBuilder()
-                .WithUrl(endpoint, options => { options.Headers.Add("Authorization", $"Bearer {api.AccessToken}"); });
-
-            if (RuntimeInfo.SupportsJIT)
-                builder.AddMessagePackProtocol();
-            else
-            {
-                // eventually we will precompile resolvers for messagepack, but this isn't working currently
-                // see https://github.com/neuecc/MessagePack-CSharp/issues/780#issuecomment-768794308.
-                builder.AddNewtonsoftJsonProtocol(options => { options.PayloadSerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; });
-            }
-
-            var newConnection = builder.Build();
-
-            // this is kind of SILLY
-            // https://github.com/dotnet/aspnetcore/issues/15198
-            newConnection.On<MultiplayerRoomState>(nameof(IMultiplayerClient.RoomStateChanged), ((IMultiplayerClient)this).RoomStateChanged);
-            newConnection.On<MultiplayerRoomUser>(nameof(IMultiplayerClient.UserJoined), ((IMultiplayerClient)this).UserJoined);
-            newConnection.On<MultiplayerRoomUser>(nameof(IMultiplayerClient.UserLeft), ((IMultiplayerClient)this).UserLeft);
-            newConnection.On<int>(nameof(IMultiplayerClient.HostChanged), ((IMultiplayerClient)this).HostChanged);
-            newConnection.On<MultiplayerRoomSettings>(nameof(IMultiplayerClient.SettingsChanged), ((IMultiplayerClient)this).SettingsChanged);
-            newConnection.On<int, MultiplayerUserState>(nameof(IMultiplayerClient.UserStateChanged), ((IMultiplayerClient)this).UserStateChanged);
-            newConnection.On(nameof(IMultiplayerClient.LoadRequested), ((IMultiplayerClient)this).LoadRequested);
-            newConnection.On(nameof(IMultiplayerClient.MatchStarted), ((IMultiplayerClient)this).MatchStarted);
-            newConnection.On(nameof(IMultiplayerClient.ResultsReady), ((IMultiplayerClient)this).ResultsReady);
-            newConnection.On<int, IEnumerable<APIMod>>(nameof(IMultiplayerClient.UserModsChanged), ((IMultiplayerClient)this).UserModsChanged);
-            newConnection.On<int, BeatmapAvailability>(nameof(IMultiplayerClient.UserBeatmapAvailabilityChanged), ((IMultiplayerClient)this).UserBeatmapAvailabilityChanged);
-
-            newConnection.Closed += ex =>
-            {
-                isConnected.Value = false;
-
-                Logger.Log(ex != null ? $"Multiplayer client lost connection: {ex}" : "Multiplayer client disconnected", LoggingTarget.Network);
-
-                // make sure a disconnect wasn't triggered (and this is still the active connection).
-                if (!cancellationToken.IsCancellationRequested)
-                    Task.Run(connect, default);
-
-                return Task.CompletedTask;
-            };
-            return newConnection;
-        }
-
         protected override void Dispose(bool isDisposing)
         {
             base.Dispose(isDisposing);
-
+            connector?.Dispose();
-            cancelExistingConnect();
         }
     }
 }

osu.Game/Online/Multiplayer/StatefulMultiplayerClient.cs

@@ -97,7 +97,8 @@ namespace osu.Game.Online.Multiplayer
         // Todo: This is temporary, until the multiplayer server returns the item id on match start or otherwise.
         private int playlistItemId;
 
-        protected StatefulMultiplayerClient()
+        [BackgroundDependencyLoader]
+        private void load()
         {
             IsConnected.BindValueChanged(connected =>
             {

osu.Game/Online/Spectator/SpectatorStreamingClient.cs

@@ -8,13 +8,9 @@ using System.Linq;
 using System.Threading.Tasks;
 using JetBrains.Annotations;
 using Microsoft.AspNetCore.SignalR.Client;
-using Microsoft.Extensions.DependencyInjection;
-using Newtonsoft.Json;
-using osu.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Framework.Logging;
 using osu.Game.Beatmaps;
 using osu.Game.Online.API;
 using osu.Game.Replays.Legacy;
@@ -34,7 +30,14 @@ namespace osu.Game.Online.Spectator
         /// </summary>
         public const double TIME_BETWEEN_SENDS = 200;
 
-        private HubConnection connection;
+        private readonly string endpoint;
+
+        [CanBeNull]
+        private IHubClientConnector connector;
+
+        private readonly IBindable<bool> isConnected = new BindableBool();
+
+        private HubConnection connection => connector?.CurrentConnection;
 
         private readonly List<int> watchingUsers = new List<int>();
 
@@ -44,13 +47,6 @@ namespace osu.Game.Online.Spectator
 
         private readonly BindableList<int> playingUsers = new BindableList<int>();
 
-        private readonly IBindable<APIState> apiState = new Bindable<APIState>();
-
-        private bool isConnected;
-
-        [Resolved]
-        private IAPIProvider api { get; set; }
-
         [CanBeNull]
         private IBeatmap currentBeatmap;
 
@@ -82,85 +78,32 @@ namespace osu.Game.Online.Spectator
         /// </summary>
         public event Action<int, SpectatorState> OnUserFinishedPlaying;
 
-        private readonly string endpoint;
-
         public SpectatorStreamingClient(EndpointConfiguration endpoints)
         {
             endpoint = endpoints.SpectatorEndpointUrl;
         }
 
         [BackgroundDependencyLoader]
-        private void load()
+        private void load(IAPIProvider api)
         {
-            apiState.BindTo(api.State);
+            connector = api.GetHubConnector(nameof(SpectatorStreamingClient), endpoint);
-            apiState.BindValueChanged(apiStateChanged, true);
-        }
 
-        private void apiStateChanged(ValueChangedEvent<APIState> state)
+            if (connector != null)
             {
-            switch (state.NewValue)
+                connector.ConfigureConnection = connection =>
                 {
-                case APIState.Failing:
+                    // until strong typed client support is added, each method must be manually bound
-                case APIState.Offline:
+                    // (see https://github.com/dotnet/aspnetcore/issues/15198)
-                    connection?.StopAsync();
-                    connection = null;
-                    break;
-
-                case APIState.Online:
-                    Task.Run(Connect);
-                    break;
-            }
-        }
-
-        protected virtual async Task Connect()
-        {
-            if (connection != null)
-                return;
-
-            var builder = new HubConnectionBuilder()
-                .WithUrl(endpoint, options => { options.Headers.Add("Authorization", $"Bearer {api.AccessToken}"); });
-
-            if (RuntimeInfo.SupportsJIT)
-                builder.AddMessagePackProtocol();
-            else
-            {
-                // eventually we will precompile resolvers for messagepack, but this isn't working currently
-                // see https://github.com/neuecc/MessagePack-CSharp/issues/780#issuecomment-768794308.
-                builder.AddNewtonsoftJsonProtocol(options => { options.PayloadSerializerSettings.ReferenceLoopHandling = ReferenceLoopHandling.Ignore; });
-            }
-
-            connection = builder.Build();
-            // until strong typed client support is added, each method must be manually bound (see https://github.com/dotnet/aspnetcore/issues/15198)
                     connection.On<int, SpectatorState>(nameof(ISpectatorClient.UserBeganPlaying), ((ISpectatorClient)this).UserBeganPlaying);
                     connection.On<int, FrameDataBundle>(nameof(ISpectatorClient.UserSentFrames), ((ISpectatorClient)this).UserSentFrames);
                     connection.On<int, SpectatorState>(nameof(ISpectatorClient.UserFinishedPlaying), ((ISpectatorClient)this).UserFinishedPlaying);
-
-            connection.Closed += async ex =>
-            {
-                isConnected = false;
-                playingUsers.Clear();
-
-                if (ex != null)
-                {
-                    Logger.Log($"Spectator client lost connection: {ex}", LoggingTarget.Network);
-                    await tryUntilConnected();
-                }
                 };
 
-            await tryUntilConnected();
+                isConnected.BindTo(connector.IsConnected);
-
+                isConnected.BindValueChanged(connected =>
-            async Task tryUntilConnected()
                 {
-                Logger.Log("Spectator client connecting...", LoggingTarget.Network);
+                    if (connected.NewValue)
-
-                while (api.State.Value == APIState.Online)
                     {
-                    try
-                    {
-                        // reconnect on any failure
-                        await connection.StartAsync();
-                        Logger.Log("Spectator client connected!", LoggingTarget.Network);
-
                         // get all the users that were previously being watched
                         int[] users;
 
@@ -170,25 +113,19 @@ namespace osu.Game.Online.Spectator
                             watchingUsers.Clear();
                         }
 
-                        // success
+                        // resubscribe to watched users.
-                        isConnected = true;
-
-                        // resubscribe to watched users
                         foreach (var userId in users)
                             WatchUser(userId);
 
                         // re-send state in case it wasn't received
                         if (isPlaying)
                             beginPlaying();
-
-                        break;
                     }
-                    catch (Exception e)
+                    else
                     {
-                        Logger.Log($"Spectator client connection error: {e}", LoggingTarget.Network);
+                        playingUsers.Clear();
-                        await Task.Delay(5000);
-                    }
                     }
+                }, true);
             }
         }
 
@@ -240,14 +177,14 @@ namespace osu.Game.Online.Spectator
         {
             Debug.Assert(isPlaying);
 
-            if (!isConnected) return;
+            if (!isConnected.Value) return;
 
             connection.SendAsync(nameof(ISpectatorServer.BeginPlaySession), currentState);
         }
 
         public void SendFrames(FrameDataBundle data)
         {
-            if (!isConnected) return;
+            if (!isConnected.Value) return;
 
             lastSend = connection.SendAsync(nameof(ISpectatorServer.SendFrameData), data);
         }
@@ -257,7 +194,7 @@ namespace osu.Game.Online.Spectator
             isPlaying = false;
             currentBeatmap = null;
 
-            if (!isConnected) return;
+            if (!isConnected.Value) return;
 
             connection.SendAsync(nameof(ISpectatorServer.EndPlaySession), currentState);
         }
@@ -271,7 +208,7 @@ namespace osu.Game.Online.Spectator
 
                 watchingUsers.Add(userId);
 
-                if (!isConnected)
+                if (!isConnected.Value)
                     return;
             }
 
@@ -284,7 +221,7 @@ namespace osu.Game.Online.Spectator
             {
                 watchingUsers.Remove(userId);
 
-                if (!isConnected)
+                if (!isConnected.Value)
                     return;
             }
 

osu.Game/OsuGame.cs

@@ -28,7 +28,6 @@ using osu.Framework.Graphics.Sprites;
 using osu.Framework.Input;
 using osu.Framework.Input.Bindings;
 using osu.Framework.Input.Events;
-using osu.Framework.Platform;
 using osu.Framework.Threading;
 using osu.Game.Beatmaps;
 using osu.Game.Collections;
@@ -52,6 +51,7 @@ using osu.Game.Updater;
 using osu.Game.Utils;
 using LogLevel = osu.Framework.Logging.LogLevel;
 using osu.Game.Database;
+using osu.Game.IO;
 
 namespace osu.Game
 {
@@ -88,7 +88,7 @@ namespace osu.Game
 
         protected SentryLogger SentryLogger;
 
-        public virtual Storage GetStorageForStableInstall() => null;
+        public virtual StableStorage GetStorageForStableInstall() => null;
 
         public float ToolbarOffset => (Toolbar?.Position.Y ?? 0) + (Toolbar?.DrawHeight ?? 0);
 

osu.Game/OsuGameBase.cs

@@ -31,6 +31,7 @@ using osu.Game.Input;
 using osu.Game.Input.Bindings;
 using osu.Game.IO;
 using osu.Game.Online;
+using osu.Game.Online.Chat;
 using osu.Game.Online.Multiplayer;
 using osu.Game.Online.Spectator;
 using osu.Game.Overlays;
@@ -155,6 +156,8 @@ namespace osu.Game
 
         protected override UserInputManager CreateUserInputManager() => new OsuUserInputManager();
 
+        private readonly BindableNumber<double> globalTrackVolumeAdjust = new BindableNumber<double>(0.5f);
+
         [BackgroundDependencyLoader]
         private void load()
         {
@@ -223,7 +226,9 @@ namespace osu.Game
 
             EndpointConfiguration endpoints = UseDevelopmentServer ? (EndpointConfiguration)new DevelopmentEndpointConfiguration() : new ProductionEndpointConfiguration();
 
-            dependencies.CacheAs(API ??= new APIAccess(LocalConfig, endpoints));
+            MessageFormatter.WebsiteRootUrl = endpoints.WebsiteRootUrl;
+
+            dependencies.CacheAs(API ??= new APIAccess(LocalConfig, endpoints, VersionHash));
 
             dependencies.CacheAs(spectatorStreaming = new SpectatorStreamingClient(endpoints));
             dependencies.CacheAs(multiplayerClient = new MultiplayerClient(endpoints));
@@ -278,9 +283,10 @@ namespace osu.Game
             RegisterImportHandler(ScoreManager);
             RegisterImportHandler(SkinManager);
 
-            // tracks play so loud our samples can't keep up.
+            // drop track volume game-wide to leave some head-room for UI effects / samples.
-            // this adds a global reduction of track volume for the time being.
+            // this means that for the time being, gameplay sample playback is louder relative to the audio track, compared to stable.
-            Audio.Tracks.AddAdjustment(AdjustableProperty.Volume, new BindableDouble(0.8));
+            // we may want to revisit this if users notice or complain about the difference (consider this a bit of a trial).
+            Audio.Tracks.AddAdjustment(AdjustableProperty.Volume, globalTrackVolumeAdjust);
 
             Beatmap = new NonNullableBindable<WorkingBeatmap>(defaultBeatmap);
 

osu.Game/Overlays/ChangelogOverlay.cs

@@ -23,7 +23,7 @@ namespace osu.Game.Overlays
     {
         public readonly Bindable<APIChangelogBuild> Current = new Bindable<APIChangelogBuild>();
 
-        private SampleChannel sampleBack;
+        private Sample sampleBack;
 
         private List<APIChangelogBuild> builds;
 

osu.Game/Overlays/MedalOverlay.cs

@@ -39,7 +39,7 @@ namespace osu.Game.Overlays
         private readonly Sprite innerSpin, outerSpin;
         private DrawableMedal drawableMedal;
 
-        private SampleChannel getSample;
+        private Sample getSample;
 
         private readonly Container content;
 

osu.Game/Overlays/Mods/ModSelectOverlay.cs

@@ -51,6 +51,11 @@ namespace osu.Game.Overlays.Mods
         /// </summary>
         protected virtual bool Stacked => true;
 
+        /// <summary>
+        /// Whether configurable <see cref="Mod"/>s can be configured by the local user.
+        /// </summary>
+        protected virtual bool AllowConfiguration => true;
+
         [NotNull]
         private Func<Mod, bool> isValidMod = m => true;
 
@@ -82,7 +87,7 @@ namespace osu.Game.Overlays.Mods
         private const float content_width = 0.8f;
         private const float footer_button_spacing = 20;
 
-        private SampleChannel sampleOn, sampleOff;
+        private Sample sampleOn, sampleOff;
 
         protected ModSelectOverlay()
         {
@@ -300,6 +305,7 @@ namespace osu.Game.Overlays.Mods
                                                 Text = "Customisation",
                                                 Action = () => ModSettingsContainer.ToggleVisibility(),
                                                 Enabled = { Value = false },
+                                                Alpha = AllowConfiguration ? 1 : 0,
                                                 Origin = Anchor.CentreLeft,
                                                 Anchor = Anchor.CentreLeft,
                                             },
@@ -512,7 +518,8 @@ namespace osu.Game.Overlays.Mods
 
                 OnModSelected(selectedMod);
 
-                if (selectedMod.RequiresConfiguration) ModSettingsContainer.Show();
+                if (selectedMod.RequiresConfiguration && AllowConfiguration)
+                    ModSettingsContainer.Show();
             }
             else
             {

osu.Game/Overlays/Mods/ModSettingsContainer.cs

@@ -52,6 +52,7 @@ namespace osu.Game.Overlays.Mods
                     new OsuScrollContainer
                     {
                         RelativeSizeAxes = Axes.Both,
+                        ScrollbarVisible = false,
                         Child = modSettingsContent = new FillFlowContainer<ModControlSection>
                         {
                             Anchor = Anchor.TopCentre,

osu.Game/Overlays/Notifications/Notification.cs

@@ -42,8 +42,8 @@ namespace osu.Game.Overlays.Notifications
         /// </summary>
         public virtual bool DisplayOnTop => true;
 
-        private SampleChannel samplePopIn;
+        private Sample samplePopIn;
-        private SampleChannel samplePopOut;
+        private Sample samplePopOut;
         protected virtual string PopInSampleName => "UI/notification-pop-in";
         protected virtual string PopOutSampleName => "UI/overlay-pop-out"; // TODO: replace with a unique sample?
 

osu.Game/Overlays/OSD/TrackedSettingToast.cs

@@ -24,9 +24,9 @@ namespace osu.Game.Overlays.OSD
         private readonly int optionCount;
         private readonly int selectedOption = -1;
 
-        private SampleChannel sampleOn;
+        private Sample sampleOn;
-        private SampleChannel sampleOff;
+        private Sample sampleOff;
-        private SampleChannel sampleChange;
+        private Sample sampleChange;
 
         public TrackedSettingToast(SettingDescription description)
             : base(description.Name, description.Value, description.Shortcut)