Merge branch 'master' into realm-key-binding-store

.editorconfig

@@ -10,14 +10,6 @@ trim_trailing_whitespace = true
 
 #Roslyn naming styles
 
-#PascalCase for public and protected members
-dotnet_naming_style.pascalcase.capitalization = pascal_case
-dotnet_naming_symbols.public_members.applicable_accessibilities = public,internal,protected,protected_internal,private_protected
-dotnet_naming_symbols.public_members.applicable_kinds = property,method,field,event
-dotnet_naming_rule.public_members_pascalcase.severity = error
-dotnet_naming_rule.public_members_pascalcase.symbols = public_members
-dotnet_naming_rule.public_members_pascalcase.style = pascalcase
-
 #camelCase for private members
 dotnet_naming_style.camelcase.capitalization = camel_case
 

.github/ISSUE_TEMPLATE/02-feature-request-issues.md

@@ -1,7 +0,0 @@
----
-name: Feature Request
-about: Propose a feature you would like to see in the game!
----
-**Describe the new feature:** 
-
-**Proposal designs of the feature:** 

.github/ISSUE_TEMPLATE/config.yml

@@ -1,5 +1,12 @@
 blank_issues_enabled: false
 contact_links:
+    - name: Suggestions or feature request
+      url: https://github.com/ppy/osu/discussions/categories/ideas
+      about: Got something you think should change or be added? Search for or start a new discussion!
+    - name: Help
+      url: https://github.com/ppy/osu/discussions/categories/q-a
+      about: osu! not working as you'd expect? Not sure it's a bug? Check the Q&A section!
     - name: osu!stable issues
       url: https://github.com/ppy/osu-stable-issues
-      about: For issues regarding osu!stable (not osu!lazer), open them here.
+      about: For osu!stable bugs (not osu!lazer), check out the dedicated repository. Note that we only accept serious bug reports.
+

README.md

@@ -97,7 +97,7 @@ Before committing your code, please run a code formatter. This can be achieved b
 
 We have adopted some cross-platform, compiler integrated analyzers. They can provide warnings when you are editing, building inside IDE or from command line, as-if they are provided by the compiler itself.
 
-JetBrains ReSharper InspectCode is also used for wider rule sets. You can run it from PowerShell with `.\InspectCode.ps1`, which is [only supported on Windows](https://youtrack.jetbrains.com/issue/RSRP-410004). Alternatively, you can install ReSharper or use Rider to get inline support in your IDE of choice.
+JetBrains ReSharper InspectCode is also used for wider rule sets. You can run it from PowerShell with `.\InspectCode.ps1`. Alternatively, you can install ReSharper or use Rider to get inline support in your IDE of choice.
 
 ## Contributing
 

Templates/Rulesets/ruleset-empty/osu.Game.Rulesets.EmptyFreeform.Tests/osu.Game.Rulesets.EmptyFreeform.Tests.csproj

@@ -10,7 +10,7 @@
     </PropertyGroup>
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

Templates/Rulesets/ruleset-empty/osu.Game.Rulesets.EmptyFreeform/EmptyFreeformDifficultyCalculator.cs

@@ -25,6 +25,6 @@ namespace osu.Game.Rulesets.EmptyFreeform
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[0];
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[0];
     }
 }

Templates/Rulesets/ruleset-empty/osu.Game.Rulesets.EmptyFreeform/Mods/EmptyFreeformModAutoplay.cs

@@ -3,7 +3,6 @@
 
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
-using osu.Game.Rulesets.EmptyFreeform.Objects;
 using osu.Game.Rulesets.EmptyFreeform.Replays;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Scoring;
@@ -11,7 +10,7 @@ using osu.Game.Users;
 
 namespace osu.Game.Rulesets.EmptyFreeform.Mods
 {
-    public class EmptyFreeformModAutoplay : ModAutoplay<EmptyFreeformHitObject>
+    public class EmptyFreeformModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

Templates/Rulesets/ruleset-example/osu.Game.Rulesets.Pippidon.Tests/osu.Game.Rulesets.Pippidon.Tests.csproj

@@ -10,7 +10,7 @@
   </PropertyGroup>
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

Templates/Rulesets/ruleset-example/osu.Game.Rulesets.Pippidon/Mods/PippidonModAutoplay.cs

@@ -4,14 +4,13 @@
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
-using osu.Game.Rulesets.Pippidon.Objects;
 using osu.Game.Rulesets.Pippidon.Replays;
 using osu.Game.Scoring;
 using osu.Game.Users;
 
 namespace osu.Game.Rulesets.Pippidon.Mods
 {
-    public class PippidonModAutoplay : ModAutoplay<PippidonHitObject>
+    public class PippidonModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

Templates/Rulesets/ruleset-example/osu.Game.Rulesets.Pippidon/PippidonDifficultyCalculator.cs

@@ -25,6 +25,6 @@ namespace osu.Game.Rulesets.Pippidon
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[0];
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[0];
     }
 }

Templates/Rulesets/ruleset-scrolling-empty/osu.Game.Rulesets.EmptyScrolling.Tests/osu.Game.Rulesets.EmptyScrolling.Tests.csproj

@@ -10,7 +10,7 @@
   </PropertyGroup>
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

Templates/Rulesets/ruleset-scrolling-empty/osu.Game.Rulesets.EmptyScrolling/EmptyScrollingDifficultyCalculator.cs

@@ -25,6 +25,6 @@ namespace osu.Game.Rulesets.EmptyScrolling
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[0];
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[0];
     }
 }

Templates/Rulesets/ruleset-scrolling-empty/osu.Game.Rulesets.EmptyScrolling/Mods/EmptyScrollingModAutoplay.cs

@@ -3,7 +3,6 @@
 
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
-using osu.Game.Rulesets.EmptyScrolling.Objects;
 using osu.Game.Rulesets.EmptyScrolling.Replays;
 using osu.Game.Scoring;
 using osu.Game.Users;
@@ -11,7 +10,7 @@ using System.Collections.Generic;
 
 namespace osu.Game.Rulesets.EmptyScrolling.Mods
 {
-    public class EmptyScrollingModAutoplay : ModAutoplay<EmptyScrollingHitObject>
+    public class EmptyScrollingModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

Templates/Rulesets/ruleset-scrolling-example/osu.Game.Rulesets.Pippidon.Tests/osu.Game.Rulesets.Pippidon.Tests.csproj

@@ -10,7 +10,7 @@
   </PropertyGroup>
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

Templates/Rulesets/ruleset-scrolling-example/osu.Game.Rulesets.Pippidon/Mods/PippidonModAutoplay.cs

@@ -4,14 +4,13 @@
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
-using osu.Game.Rulesets.Pippidon.Objects;
 using osu.Game.Rulesets.Pippidon.Replays;
 using osu.Game.Scoring;
 using osu.Game.Users;
 
 namespace osu.Game.Rulesets.Pippidon.Mods
 {
-    public class PippidonModAutoplay : ModAutoplay<PippidonHitObject>
+    public class PippidonModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

Templates/Rulesets/ruleset-scrolling-example/osu.Game.Rulesets.Pippidon/PippidonDifficultyCalculator.cs

@@ -25,6 +25,6 @@ namespace osu.Game.Rulesets.Pippidon
 
         protected override IEnumerable<DifficultyHitObject> CreateDifficultyHitObjects(IBeatmap beatmap, double clockRate) => Enumerable.Empty<DifficultyHitObject>();
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[0];
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[0];
     }
 }

osu.Android.props

@@ -51,7 +51,7 @@
     <Reference Include="Java.Interop" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.422.0" />
+    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.525.0" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.524.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.609.0" />
   </ItemGroup>
 </Project>

osu.Android/OsuGameActivity.cs

@@ -20,7 +20,8 @@ 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, Exported = true)]
     [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", "application/download", "application/x-zip", "application/x-zip-compressed" })]
+    [IntentFilter(new[] { Intent.ActionView }, Categories = new[] { Intent.CategoryDefault }, DataScheme = "content", DataMimeType = "application/x-osu-archive")]
+    [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", "application/x-osu-archive" })]
     [IntentFilter(new[] { Intent.ActionView }, Categories = new[] { Intent.CategoryBrowsable, Intent.CategoryDefault }, DataSchemes = new[] { "osu", "osump" })]
     public class OsuGameActivity : AndroidGameActivity
     {

osu.Desktop/OsuGameDesktop.cs

@@ -57,7 +57,7 @@ namespace osu.Desktop
 
         private string getStableInstallPath()
         {
-            static bool checkExists(string p) => Directory.Exists(Path.Combine(p, "Songs"));
+            static bool checkExists(string p) => Directory.Exists(Path.Combine(p, "Songs")) || File.Exists(Path.Combine(p, "osu!.cfg"));
 
             string stableInstallPath;
 

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

@@ -7,7 +7,7 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
+    <PackageReference Include="BenchmarkDotNet" Version="0.13.0" />
     <PackageReference Include="nunit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
   </ItemGroup>

osu.Game.Rulesets.Catch.Tests/TestSceneCatchModHidden.cs

@@ -4,10 +4,8 @@
 using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
-using osu.Framework.Allocation;
 using osu.Framework.Testing;
 using osu.Game.Beatmaps;
-using osu.Game.Configuration;
 using osu.Game.Rulesets.Catch.Mods;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Catch.Objects.Drawables;
@@ -21,12 +19,6 @@ namespace osu.Game.Rulesets.Catch.Tests
 {
     public class TestSceneCatchModHidden : ModTestScene
     {
-        [BackgroundDependencyLoader]
-        private void load()
-        {
-            LocalConfig.SetValue(OsuSetting.IncreaseFirstObjectVisibility, false);
-        }
-
         [Test]
         public void TestJuiceStream()
         {

osu.Game.Rulesets.Catch.Tests/TestSceneCatchPlayerLegacySkin.cs

@@ -1,8 +1,16 @@
 // 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.Extensions.IEnumerableExtensions;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Screens;
+using osu.Framework.Testing;
+using osu.Game.Screens.Play.HUD;
+using osu.Game.Skinning;
 using osu.Game.Tests.Visual;
+using osuTK;
 
 namespace osu.Game.Rulesets.Catch.Tests
 {
@@ -10,5 +18,22 @@ namespace osu.Game.Rulesets.Catch.Tests
     public class TestSceneCatchPlayerLegacySkin : LegacySkinPlayerTestScene
     {
         protected override Ruleset CreatePlayerRuleset() => new CatchRuleset();
+
+        [Test]
+        public void TestLegacyHUDComboCounterHidden([Values] bool withModifiedSkin)
+        {
+            if (withModifiedSkin)
+            {
+                AddStep("change component scale", () => Player.ChildrenOfType<LegacyScoreCounter>().First().Scale = new Vector2(2f));
+                AddStep("update target", () => Player.ChildrenOfType<SkinnableTargetContainer>().ForEach(LegacySkin.UpdateDrawableTarget));
+                AddStep("exit player", () => Player.Exit());
+                CreateTest(null);
+            }
+
+            AddAssert("legacy HUD combo counter hidden", () =>
+            {
+                return Player.ChildrenOfType<LegacyComboCounter>().All(c => c.ChildrenOfType<Container>().Single().Alpha == 0f);
+            });
+        }
     }
 }

osu.Game.Rulesets.Catch.Tests/TestSceneCatcher.cs

@@ -216,7 +216,7 @@ namespace osu.Game.Rulesets.Catch.Tests
             AddStep("enable hit lighting", () => config.SetValue(OsuSetting.HitLighting, true));
             AddStep("catch fruit", () => attemptCatch(new Fruit()));
             AddAssert("correct hit lighting colour", () =>
-                catcher.ChildrenOfType<HitExplosion>().First()?.ObjectColour == fruitColour);
+                catcher.ChildrenOfType<HitExplosion>().First()?.Entry?.ObjectColour == fruitColour);
         }
 
         [Test]

osu.Game.Rulesets.Catch.Tests/TestSceneCatcherArea.cs

@@ -95,7 +95,7 @@ namespace osu.Game.Rulesets.Catch.Tests
                 CircleSize = circleSize
             };
 
-            SetContents(() =>
+            SetContents(_ =>
             {
                 var droppedObjectContainer = new Container<CaughtObject>
                 {

osu.Game.Rulesets.Catch.Tests/TestSceneComboCounter.cs

@@ -26,7 +26,7 @@ namespace osu.Game.Rulesets.Catch.Tests
         {
             scoreProcessor = new ScoreProcessor();
 
-            SetContents(() => new CatchComboDisplay
+            SetContents(_ => new CatchComboDisplay
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Catch.Tests/TestSceneFruitObjects.cs

@@ -19,22 +19,22 @@ namespace osu.Game.Rulesets.Catch.Tests
         {
             base.LoadComplete();
 
-            AddStep("show pear", () => SetContents(() => createDrawableFruit(0)));
+            AddStep("show pear", () => SetContents(_ => createDrawableFruit(0)));
-            AddStep("show grape", () => SetContents(() => createDrawableFruit(1)));
+            AddStep("show grape", () => SetContents(_ => createDrawableFruit(1)));
-            AddStep("show pineapple / apple", () => SetContents(() => createDrawableFruit(2)));
+            AddStep("show pineapple / apple", () => SetContents(_ => createDrawableFruit(2)));
-            AddStep("show raspberry / orange", () => SetContents(() => createDrawableFruit(3)));
+            AddStep("show raspberry / orange", () => SetContents(_ => createDrawableFruit(3)));
 
-            AddStep("show banana", () => SetContents(createDrawableBanana));
+            AddStep("show banana", () => SetContents(_ => createDrawableBanana()));
 
-            AddStep("show droplet", () => SetContents(() => createDrawableDroplet()));
+            AddStep("show droplet", () => SetContents(_ => createDrawableDroplet()));
-            AddStep("show tiny droplet", () => SetContents(createDrawableTinyDroplet));
+            AddStep("show tiny droplet", () => SetContents(_ => createDrawableTinyDroplet()));
 
-            AddStep("show hyperdash pear", () => SetContents(() => createDrawableFruit(0, true)));
+            AddStep("show hyperdash pear", () => SetContents(_ => createDrawableFruit(0, true)));
-            AddStep("show hyperdash grape", () => SetContents(() => createDrawableFruit(1, true)));
+            AddStep("show hyperdash grape", () => SetContents(_ => createDrawableFruit(1, true)));
-            AddStep("show hyperdash pineapple / apple", () => SetContents(() => createDrawableFruit(2, true)));
+            AddStep("show hyperdash pineapple / apple", () => SetContents(_ => createDrawableFruit(2, true)));
-            AddStep("show hyperdash raspberry / orange", () => SetContents(() => createDrawableFruit(3, true)));
+            AddStep("show hyperdash raspberry / orange", () => SetContents(_ => createDrawableFruit(3, true)));
 
-            AddStep("show hyperdash droplet", () => SetContents(() => createDrawableDroplet(true)));
+            AddStep("show hyperdash droplet", () => SetContents(_ => createDrawableDroplet(true)));
         }
 
         private Drawable createDrawableFruit(int indexInBeatmap, bool hyperdash = false) =>

osu.Game.Rulesets.Catch.Tests/TestSceneFruitVisualChange.cs

@@ -14,13 +14,13 @@ namespace osu.Game.Rulesets.Catch.Tests
 
         protected override void LoadComplete()
         {
-            AddStep("fruit changes visual and hyper", () => SetContents(() => new TestDrawableCatchHitObjectSpecimen(new DrawableFruit(new Fruit
+            AddStep("fruit changes visual and hyper", () => SetContents(_ => new TestDrawableCatchHitObjectSpecimen(new DrawableFruit(new Fruit
             {
                 IndexInBeatmapBindable = { BindTarget = indexInBeatmap },
                 HyperDashBindable = { BindTarget = hyperDash },
             }))));
 
-            AddStep("droplet changes hyper", () => SetContents(() => new TestDrawableCatchHitObjectSpecimen(new DrawableDroplet(new Droplet
+            AddStep("droplet changes hyper", () => SetContents(_ => new TestDrawableCatchHitObjectSpecimen(new DrawableDroplet(new Droplet
             {
                 HyperDashBindable = { BindTarget = hyperDash },
             }))));

osu.Game.Rulesets.Catch.Tests/TestSceneLegacyBeatmapSkin.cs

@@ -32,28 +32,28 @@ namespace osu.Game.Rulesets.Catch.Tests
         [TestCase(true, false)]
         [TestCase(false, true)]
         [TestCase(false, false)]
-        public override void TestBeatmapComboColours(bool userHasCustomColours, bool useBeatmapSkin)
+        public void TestBeatmapComboColours(bool userHasCustomColours, bool useBeatmapSkin)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColours(userHasCustomColours, useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, true, userHasCustomColours);
             AddAssert("is beatmap skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestBeatmapSkin.Colours));
         }
 
         [TestCase(true)]
         [TestCase(false)]
-        public override void TestBeatmapComboColoursOverride(bool useBeatmapSkin)
+        public void TestBeatmapComboColoursOverride(bool useBeatmapSkin)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColoursOverride(useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, false, true);
             AddAssert("is user custom skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestSkin.Colours));
         }
 
         [TestCase(true)]
         [TestCase(false)]
-        public override void TestBeatmapComboColoursOverrideWithDefaultColours(bool useBeatmapSkin)
+        public void TestBeatmapComboColoursOverrideWithDefaultColours(bool useBeatmapSkin)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColoursOverrideWithDefaultColours(useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, false, false);
             AddAssert("is default user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(SkinConfiguration.DefaultComboColours));
         }
 
@@ -61,10 +61,10 @@ namespace osu.Game.Rulesets.Catch.Tests
         [TestCase(false, true)]
         [TestCase(true, false)]
         [TestCase(false, false)]
-        public override void TestBeatmapNoComboColours(bool useBeatmapSkin, bool useBeatmapColour)
+        public void TestBeatmapNoComboColours(bool useBeatmapSkin, bool useBeatmapColour)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, false);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, false));
-            base.TestBeatmapNoComboColours(useBeatmapSkin, useBeatmapColour);
+            ConfigureTest(useBeatmapSkin, useBeatmapColour, false);
             AddAssert("is default user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(SkinConfiguration.DefaultComboColours));
         }
 
@@ -72,10 +72,10 @@ namespace osu.Game.Rulesets.Catch.Tests
         [TestCase(false, true)]
         [TestCase(true, false)]
         [TestCase(false, false)]
-        public override void TestBeatmapNoComboColoursSkinOverride(bool useBeatmapSkin, bool useBeatmapColour)
+        public void TestBeatmapNoComboColoursSkinOverride(bool useBeatmapSkin, bool useBeatmapColour)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, false);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, false));
-            base.TestBeatmapNoComboColoursSkinOverride(useBeatmapSkin, useBeatmapColour);
+            ConfigureTest(useBeatmapSkin, useBeatmapColour, true);
             AddAssert("is custom user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestSkin.Colours));
         }
 
@@ -83,7 +83,7 @@ namespace osu.Game.Rulesets.Catch.Tests
         [TestCase(false)]
         public void TestBeatmapHyperDashColours(bool useBeatmapSkin)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, true));
             ConfigureTest(useBeatmapSkin, true, true);
             AddAssert("is custom hyper dash colours", () => ((CatchExposedPlayer)TestPlayer).UsableHyperDashColour == TestBeatmapSkin.HYPER_DASH_COLOUR);
             AddAssert("is custom hyper dash after image colours", () => ((CatchExposedPlayer)TestPlayer).UsableHyperDashAfterImageColour == TestBeatmapSkin.HYPER_DASH_AFTER_IMAGE_COLOUR);
@@ -94,7 +94,7 @@ namespace osu.Game.Rulesets.Catch.Tests
         [TestCase(false)]
         public void TestBeatmapHyperDashColoursOverride(bool useBeatmapSkin)
         {
-            TestBeatmap = new CatchCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new CatchCustomSkinWorkingBeatmap(audio, true));
             ConfigureTest(useBeatmapSkin, false, true);
             AddAssert("is custom hyper dash colours", () => ((CatchExposedPlayer)TestPlayer).UsableHyperDashColour == TestSkin.HYPER_DASH_COLOUR);
             AddAssert("is custom hyper dash after image colours", () => ((CatchExposedPlayer)TestPlayer).UsableHyperDashAfterImageColour == TestSkin.HYPER_DASH_AFTER_IMAGE_COLOUR);

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

@@ -2,7 +2,7 @@
   <Import Project="..\osu.TestProject.props" />
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

osu.Game.Rulesets.Catch/CatchRuleset.cs

@@ -161,13 +161,13 @@ namespace osu.Game.Rulesets.Catch
             switch (result)
             {
                 case HitResult.LargeTickHit:
-                    return "large droplet";
+                    return "Large droplet";
 
                 case HitResult.SmallTickHit:
-                    return "small droplet";
+                    return "Small droplet";
 
                 case HitResult.LargeBonus:
-                    return "banana";
+                    return "Banana";
             }
 
             return base.GetDisplayNameForHitResult(result);

osu.Game.Rulesets.Catch/Difficulty/CatchDifficultyCalculator.cs

@@ -67,7 +67,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty
             }
         }
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods)
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate)
         {
             halfCatcherWidth = Catcher.CalculateCatchWidth(beatmap.BeatmapInfo.BaseDifficulty) * 0.5f;
 
@@ -76,7 +76,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty
 
             return new Skill[]
             {
-                new Movement(mods, halfCatcherWidth),
+                new Movement(mods, halfCatcherWidth, clockRate),
             };
         }
 

osu.Game.Rulesets.Catch/Difficulty/Preprocessing/CatchDifficultyHitObject.cs

@@ -24,8 +24,6 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Preprocessing
         /// </summary>
         public readonly double StrainTime;
 
-        public readonly double ClockRate;
-
         public CatchDifficultyHitObject(HitObject hitObject, HitObject lastObject, double clockRate, float halfCatcherWidth)
             : base(hitObject, lastObject, clockRate)
         {
@@ -37,7 +35,6 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Preprocessing
 
             // Every strain interval is hard capped at the equivalent of 375 BPM streaming speed as a safety measure
             StrainTime = Math.Max(40, DeltaTime);
-            ClockRate = clockRate;
         }
     }
 }

osu.Game.Rulesets.Catch/Difficulty/Skills/Movement.cs

@@ -28,10 +28,21 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Skills
         private float lastDistanceMoved;
         private double lastStrainTime;
 
-        public Movement(Mod[] mods, float halfCatcherWidth)
+        /// <summary>
+        /// The speed multiplier applied to the player's catcher.
+        /// </summary>
+        private readonly double catcherSpeedMultiplier;
+
+        public Movement(Mod[] mods, float halfCatcherWidth, double clockRate)
             : base(mods)
         {
             HalfCatcherWidth = halfCatcherWidth;
+
+            // In catch, clockrate adjustments do not only affect the timings of hitobjects,
+            // but also the speed of the player's catcher, which has an impact on difficulty
+            // TODO: Support variable clockrates caused by mods such as ModTimeRamp
+            //  (perhaps by using IApplicableToRate within the CatchDifficultyHitObject constructor to set a catcher speed for each object before processing)
+            catcherSpeedMultiplier = clockRate;
         }
 
         protected override double StrainValueOf(DifficultyHitObject current)
@@ -48,7 +59,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Skills
 
             float distanceMoved = playerPosition - lastPlayerPosition.Value;
 
-            double weightedStrainTime = catchCurrent.StrainTime + 13 + (3 / catchCurrent.ClockRate);
+            double weightedStrainTime = catchCurrent.StrainTime + 13 + (3 / catcherSpeedMultiplier);
 
             double distanceAddition = (Math.Pow(Math.Abs(distanceMoved), 1.3) / 510);
             double sqrtStrain = Math.Sqrt(weightedStrainTime);
@@ -81,7 +92,7 @@ namespace osu.Game.Rulesets.Catch.Difficulty.Skills
                     playerPosition = catchCurrent.NormalizedPosition;
                 }
 
-                distanceAddition *= 1.0 + edgeDashBonus * ((20 - catchCurrent.LastObject.DistanceToHyperDash) / 20) * Math.Pow((Math.Min(catchCurrent.StrainTime * catchCurrent.ClockRate, 265) / 265), 1.5); // Edge Dashes are easier at lower ms values
+                distanceAddition *= 1.0 + edgeDashBonus * ((20 - catchCurrent.LastObject.DistanceToHyperDash) / 20) * Math.Pow((Math.Min(catchCurrent.StrainTime * catcherSpeedMultiplier, 265) / 265), 1.5); // Edge Dashes are easier at lower ms values
             }
 
             lastPlayerPosition = playerPosition;

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

@@ -3,7 +3,6 @@
 
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
-using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Catch.Replays;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Scoring;
@@ -11,7 +10,7 @@ using osu.Game.Users;
 
 namespace osu.Game.Rulesets.Catch.Mods
 {
-    public class CatchModAutoplay : ModAutoplay<CatchHitObject>
+    public class CatchModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

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

@@ -29,8 +29,7 @@ namespace osu.Game.Rulesets.Catch.Mods
         }
 
         protected override void ApplyIncreasedVisibilityState(DrawableHitObject hitObject, ArmedState state)
-        {
+            => ApplyNormalVisibilityState(hitObject, state);
-        }
 
         protected override void ApplyNormalVisibilityState(DrawableHitObject hitObject, ArmedState state)
         {

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtFruit.cs

@@ -1,7 +1,6 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
-using osu.Framework.Bindables;
 using osu.Game.Rulesets.Catch.Skinning.Default;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables
@@ -9,21 +8,11 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
     /// <summary>
     /// Represents a <see cref="Fruit"/> caught by the catcher.
     /// </summary>
-    public class CaughtFruit : CaughtObject, IHasFruitState
+    public class CaughtFruit : CaughtObject
     {
-        public Bindable<FruitVisualRepresentation> VisualRepresentation { get; } = new Bindable<FruitVisualRepresentation>();
-
         public CaughtFruit()
             : base(CatchSkinComponents.Fruit, _ => new FruitPiece())
         {
         }
-
-        public override void CopyStateFrom(IHasCatchObjectState objectState)
-        {
-            base.CopyStateFrom(objectState);
-
-            var fruitState = (IHasFruitState)objectState;
-            VisualRepresentation.Value = fruitState.VisualRepresentation.Value;
-        }
     }
 }

osu.Game.Rulesets.Catch/Objects/Drawables/CaughtObject.cs

@@ -20,6 +20,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         public PalpableCatchHitObject HitObject { get; private set; }
         public Bindable<Color4> AccentColour { get; } = new Bindable<Color4>();
         public Bindable<bool> HyperDash { get; } = new Bindable<bool>();
+        public Bindable<int> IndexInBeatmap { get; } = new Bindable<int>();
 
         public Vector2 DisplaySize => Size * Scale;
 
@@ -51,6 +52,7 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
             Rotation = objectState.DisplayRotation;
             AccentColour.Value = objectState.AccentColour.Value;
             HyperDash.Value = objectState.HyperDash.Value;
+            IndexInBeatmap.Value = objectState.IndexInBeatmap.Value;
         }
 
         protected override void FreeAfterUse()

osu.Game.Rulesets.Catch/Objects/Drawables/DrawableFruit.cs

@@ -3,17 +3,14 @@
 
 using JetBrains.Annotations;
 using osu.Framework.Allocation;
-using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Game.Rulesets.Catch.Skinning.Default;
 using osu.Game.Skinning;
 
 namespace osu.Game.Rulesets.Catch.Objects.Drawables
 {
-    public class DrawableFruit : DrawablePalpableCatchHitObject, IHasFruitState
+    public class DrawableFruit : DrawablePalpableCatchHitObject
     {
-        public Bindable<FruitVisualRepresentation> VisualRepresentation { get; } = new Bindable<FruitVisualRepresentation>();
-
         public DrawableFruit()
             : this(null)
         {
@@ -27,11 +24,6 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
         [BackgroundDependencyLoader]
         private void load()
         {
-            IndexInBeatmap.BindValueChanged(change =>
-            {
-                VisualRepresentation.Value = (FruitVisualRepresentation)(change.NewValue % 4);
-            }, true);
-
             ScalingContainer.Child = new SkinnableDrawable(
                 new CatchSkinComponent(CatchSkinComponents.Fruit),
                 _ => new FruitPiece());
@@ -44,12 +36,4 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
             ScalingContainer.RotateTo((RandomSingle(1) - 0.5f) * 40);
         }
     }
-
-    public enum FruitVisualRepresentation
-    {
-        Pear,
-        Grape,
-        Pineapple,
-        Raspberry,
-    }
 }

osu.Game.Rulesets.Catch/Objects/Drawables/IHasCatchObjectState.cs

@@ -18,6 +18,8 @@ namespace osu.Game.Rulesets.Catch.Objects.Drawables
 
         Bindable<bool> HyperDash { get; }
 
+        Bindable<int> IndexInBeatmap { get; }
+
         Vector2 DisplaySize { get; }
 
         float DisplayRotation { get; }

osu.Game.Rulesets.Catch/Objects/Drawables/IHasFruitState.cs

@@ -1,15 +0,0 @@
-// 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.Bindables;
-
-namespace osu.Game.Rulesets.Catch.Objects.Drawables
-{
-    /// <summary>
-    /// Provides a visual state of a <see cref="Fruit"/>.
-    /// </summary>
-    public interface IHasFruitState : IHasCatchObjectState
-    {
-        Bindable<FruitVisualRepresentation> VisualRepresentation { get; }
-    }
-}

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

@@ -9,5 +9,7 @@ namespace osu.Game.Rulesets.Catch.Objects
     public class Fruit : PalpableCatchHitObject
     {
         public override Judgement CreateJudgement() => new CatchJudgement();
+
+        public static FruitVisualRepresentation GetVisualRepresentation(int indexInBeatmap) => (FruitVisualRepresentation)(indexInBeatmap % 4);
     }
 }

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

@@ -0,0 +1,13 @@
+// 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.
+
+namespace osu.Game.Rulesets.Catch.Objects
+{
+    public enum FruitVisualRepresentation
+    {
+        Pear,
+        Grape,
+        Pineapple,
+        Raspberry,
+    }
+}

osu.Game.Rulesets.Catch/Scoring/CatchHitWindows.cs

@@ -1,22 +0,0 @@
-// 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.Catch.Scoring
-{
-    public class CatchHitWindows : HitWindows
-    {
-        public override bool IsHitResultAllowed(HitResult result)
-        {
-            switch (result)
-            {
-                case HitResult.Great:
-                case HitResult.Miss:
-                    return true;
-            }
-
-            return false;
-        }
-    }
-}

osu.Game.Rulesets.Catch/Skinning/Default/CatchHitObjectPiece.cs

@@ -15,6 +15,7 @@ namespace osu.Game.Rulesets.Catch.Skinning.Default
     {
         public readonly Bindable<Color4> AccentColour = new Bindable<Color4>();
         public readonly Bindable<bool> HyperDash = new Bindable<bool>();
+        public readonly Bindable<int> IndexInBeatmap = new Bindable<int>();
 
         [Resolved]
         protected IHasCatchObjectState ObjectState { get; private set; }
@@ -37,6 +38,7 @@ namespace osu.Game.Rulesets.Catch.Skinning.Default
 
             AccentColour.BindTo(ObjectState.AccentColour);
             HyperDash.BindTo(ObjectState.HyperDash);
+            IndexInBeatmap.BindTo(ObjectState.IndexInBeatmap);
 
             HyperDash.BindValueChanged(hyper =>
             {

osu.Game.Rulesets.Catch/Skinning/Default/FruitPiece.cs

@@ -3,7 +3,7 @@
 
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
-using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Catch.Objects;
 
 namespace osu.Game.Rulesets.Catch.Skinning.Default
 {
@@ -39,8 +39,10 @@ namespace osu.Game.Rulesets.Catch.Skinning.Default
         {
             base.LoadComplete();
 
-            var fruitState = (IHasFruitState)ObjectState;
+            IndexInBeatmap.BindValueChanged(index =>
-            VisualRepresentation.BindTo(fruitState.VisualRepresentation);
+            {
+                VisualRepresentation.Value = Fruit.GetVisualRepresentation(index.NewValue);
+            }, true);
         }
     }
 }

osu.Game.Rulesets.Catch/Skinning/Default/FruitPulpFormation.cs

@@ -2,7 +2,7 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using osu.Framework.Bindables;
-using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Catch.Objects;
 using osuTK;
 
 namespace osu.Game.Rulesets.Catch.Skinning.Default

osu.Game.Rulesets.Catch/Skinning/Legacy/CatchLegacySkinTransformer.cs

@@ -1,8 +1,10 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System.Linq;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
+using osu.Game.Screens.Play.HUD;
 using osu.Game.Skinning;
 using osuTK.Graphics;
 
@@ -22,38 +24,46 @@ namespace osu.Game.Rulesets.Catch.Skinning.Legacy
 
         public override Drawable GetDrawableComponent(ISkinComponent component)
         {
-            if (component is HUDSkinComponent hudComponent)
+            if (component is SkinnableTargetComponent targetComponent)
             {
-                switch (hudComponent.Component)
+                switch (targetComponent.Target)
+                {
+                    case SkinnableTarget.MainHUDComponents:
+                        var components = Source.GetDrawableComponent(component) as SkinnableTargetComponentsContainer;
+
+                        if (providesComboCounter && components != null)
                         {
-                    case HUDSkinComponents.ComboCounter:
                             // catch may provide its own combo counter; hide the default.
-                        return providesComboCounter ? Drawable.Empty() : null;
+                            // todo: this should be done in an elegant way per ruleset, defining which HUD skin components should be displayed.
+                            foreach (var legacyComboCounter in components.OfType<LegacyComboCounter>())
+                                legacyComboCounter.HiddenByRulesetImplementation = false;
+                        }
+
+                        return components;
                 }
             }
 
-            if (!(component is CatchSkinComponent catchSkinComponent))
+            if (component is CatchSkinComponent catchSkinComponent)
-                return null;
+            {
-
                 switch (catchSkinComponent.Component)
                 {
                     case CatchSkinComponents.Fruit:
                         if (GetTexture("fruit-pear") != null)
                             return new LegacyFruitPiece();
 
-                    break;
+                        return null;
 
                     case CatchSkinComponents.Banana:
                         if (GetTexture("fruit-bananas") != null)
                             return new LegacyBananaPiece();
 
-                    break;
+                        return null;
 
                     case CatchSkinComponents.Droplet:
                         if (GetTexture("fruit-drop") != null)
                             return new LegacyDropletPiece();
 
-                    break;
+                        return null;
 
                     case CatchSkinComponents.CatcherIdle:
                         return this.GetAnimation("fruit-catcher-idle", true, true, true) ??
@@ -71,10 +81,11 @@ namespace osu.Game.Rulesets.Catch.Skinning.Legacy
                         if (providesComboCounter)
                             return new LegacyCatchComboCounter(Source);
 
-                    break;
+                        return null;
+                }
             }
 
-            return null;
+            return Source.GetDrawableComponent(component);
         }
 
         public override IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup)

osu.Game.Rulesets.Catch/Skinning/Legacy/LegacyBananaPiece.cs

@@ -3,7 +3,7 @@
 
 using osu.Framework.Graphics.Textures;
 
-namespace osu.Game.Rulesets.Catch.Skinning
+namespace osu.Game.Rulesets.Catch.Skinning.Legacy
 {
     public class LegacyBananaPiece : LegacyCatchHitObjectPiece
     {

osu.Game.Rulesets.Catch/Skinning/Legacy/LegacyCatchHitObjectPiece.cs

@@ -13,12 +13,13 @@ using osu.Game.Skinning;
 using osuTK;
 using osuTK.Graphics;
 
-namespace osu.Game.Rulesets.Catch.Skinning
+namespace osu.Game.Rulesets.Catch.Skinning.Legacy
 {
     public abstract class LegacyCatchHitObjectPiece : PoolableDrawable
     {
         public readonly Bindable<Color4> AccentColour = new Bindable<Color4>();
         public readonly Bindable<bool> HyperDash = new Bindable<bool>();
+        public readonly Bindable<int> IndexInBeatmap = new Bindable<int>();
 
         private readonly Sprite colouredSprite;
         private readonly Sprite overlaySprite;
@@ -64,6 +65,7 @@ namespace osu.Game.Rulesets.Catch.Skinning
 
             AccentColour.BindTo(ObjectState.AccentColour);
             HyperDash.BindTo(ObjectState.HyperDash);
+            IndexInBeatmap.BindTo(ObjectState.IndexInBeatmap);
 
             hyperSprite.Colour = Skin.GetConfig<CatchSkinColour, Color4>(CatchSkinColour.HyperDashFruit)?.Value ??
                                  Skin.GetConfig<CatchSkinColour, Color4>(CatchSkinColour.HyperDash)?.Value ??

osu.Game.Rulesets.Catch/Skinning/Legacy/LegacyDropletPiece.cs

@@ -4,7 +4,7 @@
 using osu.Framework.Graphics.Textures;
 using osuTK;
 
-namespace osu.Game.Rulesets.Catch.Skinning
+namespace osu.Game.Rulesets.Catch.Skinning.Legacy
 {
     public class LegacyDropletPiece : LegacyCatchHitObjectPiece
     {

osu.Game.Rulesets.Catch/Skinning/Legacy/LegacyFruitPiece.cs

@@ -1,23 +1,20 @@
 // 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.Bindables;
+using osu.Game.Rulesets.Catch.Objects;
-using osu.Game.Rulesets.Catch.Objects.Drawables;
 
 namespace osu.Game.Rulesets.Catch.Skinning.Legacy
 {
     internal class LegacyFruitPiece : LegacyCatchHitObjectPiece
     {
-        public readonly Bindable<FruitVisualRepresentation> VisualRepresentation = new Bindable<FruitVisualRepresentation>();
-
         protected override void LoadComplete()
         {
             base.LoadComplete();
 
-            var fruitState = (IHasFruitState)ObjectState;
+            IndexInBeatmap.BindValueChanged(index =>
-            VisualRepresentation.BindTo(fruitState.VisualRepresentation);
+            {
-
+                setTexture(Fruit.GetVisualRepresentation(index.NewValue));
-            VisualRepresentation.BindValueChanged(visual => setTexture(visual.NewValue), true);
+            }, true);
         }
 
         private void setTexture(FruitVisualRepresentation visualRepresentation)

osu.Game.Rulesets.Catch/UI/CatchComboDisplay.cs

@@ -25,9 +25,9 @@ namespace osu.Game.Rulesets.Catch.UI
         {
         }
 
-        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        protected override void SkinChanged(ISkinSource skin)
         {
-            base.SkinChanged(skin, allowFallback);
+            base.SkinChanged(skin);
             ComboCounter?.UpdateCombo(currentCombo);
         }
 

osu.Game.Rulesets.Catch/UI/Catcher.cs

@@ -126,8 +126,7 @@ namespace osu.Game.Rulesets.Catch.UI
         private float hyperDashTargetPosition;
         private Bindable<bool> hitLighting;
 
-        private readonly DrawablePool<HitExplosion> hitExplosionPool;
+        private readonly HitExplosionContainer hitExplosionContainer;
-        private readonly Container<HitExplosion> hitExplosionContainer;
 
         private readonly DrawablePool<CaughtFruit> caughtFruitPool;
         private readonly DrawablePool<CaughtBanana> caughtBananaPool;
@@ -148,7 +147,6 @@ namespace osu.Game.Rulesets.Catch.UI
 
             InternalChildren = new Drawable[]
             {
-                hitExplosionPool = new DrawablePool<HitExplosion>(10),
                 caughtFruitPool = new DrawablePool<CaughtFruit>(50),
                 caughtBananaPool = new DrawablePool<CaughtBanana>(100),
                 // less capacity is needed compared to fruit because droplet is not stacked
@@ -173,7 +171,7 @@ namespace osu.Game.Rulesets.Catch.UI
                     Anchor = Anchor.TopCentre,
                     Alpha = 0,
                 },
-                hitExplosionContainer = new Container<HitExplosion>
+                hitExplosionContainer = new HitExplosionContainer
                 {
                     Anchor = Anchor.TopCentre,
                     Origin = Anchor.BottomCentre,
@@ -297,7 +295,6 @@ namespace osu.Game.Rulesets.Catch.UI
 
             caughtObjectContainer.RemoveAll(d => d.HitObject == drawableObject.HitObject);
             droppedObjectTarget.RemoveAll(d => d.HitObject == drawableObject.HitObject);
-            hitExplosionContainer.RemoveAll(d => d.HitObject == drawableObject.HitObject);
         }
 
         /// <summary>
@@ -399,9 +396,9 @@ namespace osu.Game.Rulesets.Catch.UI
 
         private void updateTrailVisibility() => trails.DisplayTrail = Dashing || HyperDashing;
 
-        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        protected override void SkinChanged(ISkinSource skin)
         {
-            base.SkinChanged(skin, allowFallback);
+            base.SkinChanged(skin);
 
             hyperDashColour =
                 skin.GetConfig<CatchSkinColour, Color4>(CatchSkinColour.HyperDash)?.Value ??
@@ -508,15 +505,8 @@ namespace osu.Game.Rulesets.Catch.UI
             return position;
         }
 
-        private void addLighting(CatchHitObject hitObject, float x, Color4 colour)
+        private void addLighting(CatchHitObject hitObject, float x, Color4 colour) =>
-        {
+            hitExplosionContainer.Add(new HitExplosionEntry(Time.Current, x, hitObject.Scale, colour, hitObject.RandomSeed));
-            HitExplosion hitExplosion = hitExplosionPool.Get();
-            hitExplosion.HitObject = hitObject;
-            hitExplosion.X = x;
-            hitExplosion.Scale = new Vector2(hitObject.Scale);
-            hitExplosion.ObjectColour = colour;
-            hitExplosionContainer.Add(hitExplosion);
-        }
 
         private CaughtObject getCaughtObject(PalpableCatchHitObject source)
         {

osu.Game.Rulesets.Catch/UI/HitExplosion.cs

@@ -5,31 +5,16 @@ using osu.Framework.Extensions.Color4Extensions;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Effects;
-using osu.Framework.Graphics.Pooling;
 using osu.Framework.Utils;
-using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Objects.Pooling;
+using osu.Game.Utils;
 using osuTK;
 using osuTK.Graphics;
 
 namespace osu.Game.Rulesets.Catch.UI
 {
-    public class HitExplosion : PoolableDrawable
+    public class HitExplosion : PoolableDrawableWithLifetime<HitExplosionEntry>
     {
-        private Color4 objectColour;
-        public CatchHitObject HitObject;
-
-        public Color4 ObjectColour
-        {
-            get => objectColour;
-            set
-            {
-                if (objectColour == value) return;
-
-                objectColour = value;
-                onColourChanged();
-            }
-        }
-
         private readonly CircularContainer largeFaint;
         private readonly CircularContainer smallFaint;
         private readonly CircularContainer directionalGlow1;
@@ -83,9 +68,19 @@ namespace osu.Game.Rulesets.Catch.UI
             };
         }
 
-        protected override void PrepareForUse()
+        protected override void OnApply(HitExplosionEntry entry)
         {
-            base.PrepareForUse();
+            X = entry.Position;
+            Scale = new Vector2(entry.Scale);
+            setColour(entry.ObjectColour);
+
+            using (BeginAbsoluteSequence(entry.LifetimeStart))
+                applyTransforms(entry.RNGSeed);
+        }
+
+        private void applyTransforms(int randomSeed)
+        {
+            ClearTransforms(true);
 
             const double duration = 400;
 
@@ -96,14 +91,13 @@ namespace osu.Game.Rulesets.Catch.UI
                 .FadeOut(duration * 2);
 
             const float angle_variangle = 15; // should be less than 45
-            directionalGlow1.Rotation = RNG.NextSingle(-angle_variangle, angle_variangle);
+            directionalGlow1.Rotation = StatelessRNG.NextSingle(-angle_variangle, angle_variangle, randomSeed, 4);
-            directionalGlow2.Rotation = RNG.NextSingle(-angle_variangle, angle_variangle);
+            directionalGlow2.Rotation = StatelessRNG.NextSingle(-angle_variangle, angle_variangle, randomSeed, 5);
 
-            this.FadeInFromZero(50).Then().FadeOut(duration, Easing.Out);
+            this.FadeInFromZero(50).Then().FadeOut(duration, Easing.Out).Expire();
-            Expire(true);
         }
 
-        private void onColourChanged()
+        private void setColour(Color4 objectColour)
         {
             const float roundness = 100;
 

osu.Game.Rulesets.Catch/UI/HitExplosionContainer.cs

@@ -0,0 +1,22 @@
+// 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.Graphics.Pooling;
+using osu.Game.Rulesets.Objects.Pooling;
+
+namespace osu.Game.Rulesets.Catch.UI
+{
+    public class HitExplosionContainer : PooledDrawableWithLifetimeContainer<HitExplosionEntry, HitExplosion>
+    {
+        protected override bool RemoveRewoundEntry => true;
+
+        private readonly DrawablePool<HitExplosion> pool;
+
+        public HitExplosionContainer()
+        {
+            AddInternal(pool = new DrawablePool<HitExplosion>(10));
+        }
+
+        protected override HitExplosion GetDrawable(HitExplosionEntry entry) => pool.Get(d => d.Apply(entry));
+    }
+}

osu.Game.Rulesets.Catch/UI/HitExplosionEntry.cs

@@ -0,0 +1,25 @@
+// 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.Graphics.Performance;
+using osuTK.Graphics;
+
+namespace osu.Game.Rulesets.Catch.UI
+{
+    public class HitExplosionEntry : LifetimeEntry
+    {
+        public readonly float Position;
+        public readonly float Scale;
+        public readonly Color4 ObjectColour;
+        public readonly int RNGSeed;
+
+        public HitExplosionEntry(double startTime, float position, float scale, Color4 objectColour, int rngSeed)
+        {
+            LifetimeStart = startTime;
+            Position = position;
+            Scale = scale;
+            ObjectColour = objectColour;
+            RNGSeed = rngSeed;
+        }
+    }
+}

osu.Game.Rulesets.Mania.Tests/Skinning/ManiaHitObjectTestScene.cs

@@ -18,7 +18,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [SetUp]
         public void SetUp() => Schedule(() =>
         {
-            SetContents(() => new FillFlowContainer
+            SetContents(_ => new FillFlowContainer
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneColumnBackground.cs

@@ -15,7 +15,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() => new FillFlowContainer
+            SetContents(_ => new FillFlowContainer
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneColumnHitObjectArea.cs

@@ -15,7 +15,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() => new FillFlowContainer
+            SetContents(_ => new FillFlowContainer
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneDrawableJudgement.cs

@@ -23,7 +23,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
             {
                 if (hitWindows.IsHitResultAllowed(result))
                 {
-                    AddStep("Show " + result.GetDescription(), () => SetContents(() =>
+                    AddStep("Show " + result.GetDescription(), () => SetContents(_ =>
                         new DrawableManiaJudgement(new JudgementResult(new HitObject { StartTime = Time.Current }, new Judgement())
                         {
                             Type = result

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneHitExplosion.cs

@@ -53,7 +53,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() =>
+            SetContents(_ =>
             {
                 var pool = new DrawablePool<PoolableHitExplosion>(5);
                 hitExplosionPools.Add(pool);

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneKeyArea.cs

@@ -15,7 +15,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() => new FillFlowContainer
+            SetContents(_ => new FillFlowContainer
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/Skinning/TestScenePlayfield.cs

@@ -23,7 +23,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
                     new StageDefinition { Columns = 2 }
                 };
 
-                SetContents(() => new ManiaPlayfield(stageDefinitions));
+                SetContents(_ => new ManiaPlayfield(stageDefinitions));
             });
         }
 
@@ -38,7 +38,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
                     new StageDefinition { Columns = 2 }
                 };
 
-                SetContents(() => new ManiaPlayfield(stageDefinitions));
+                SetContents(_ => new ManiaPlayfield(stageDefinitions));
             });
         }
 

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneStage.cs

@@ -12,7 +12,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() =>
+            SetContents(_ =>
             {
                 ManiaAction normalAction = ManiaAction.Key1;
                 ManiaAction specialAction = ManiaAction.Special1;

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneStageBackground.cs

@@ -14,7 +14,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() => new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageBackground, stageDefinition: new StageDefinition { Columns = 4 }),
+            SetContents(_ => new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageBackground, stageDefinition: new StageDefinition { Columns = 4 }),
                 _ => new DefaultStageBackground())
             {
                 Anchor = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/Skinning/TestSceneStageForeground.cs

@@ -13,7 +13,7 @@ namespace osu.Game.Rulesets.Mania.Tests.Skinning
         [BackgroundDependencyLoader]
         private void load()
         {
-            SetContents(() => new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageForeground, stageDefinition: new StageDefinition { Columns = 4 }), _ => null)
+            SetContents(_ => new SkinnableDrawable(new ManiaSkinComponent(ManiaSkinComponents.StageForeground, stageDefinition: new StageDefinition { Columns = 4 }), _ => null)
             {
                 Anchor = Anchor.Centre,
                 Origin = Anchor.Centre,

osu.Game.Rulesets.Mania.Tests/TestSceneManiaHitObjectSamples.cs

@@ -11,7 +11,7 @@ namespace osu.Game.Rulesets.Mania.Tests
     public class TestSceneManiaHitObjectSamples : HitObjectSampleTest
     {
         protected override Ruleset CreatePlayerRuleset() => new ManiaRuleset();
-        protected override IResourceStore<byte[]> Resources => new DllResourceStore(Assembly.GetAssembly(typeof(TestSceneManiaHitObjectSamples)));
+        protected override IResourceStore<byte[]> RulesetResources => new DllResourceStore(Assembly.GetAssembly(typeof(TestSceneManiaHitObjectSamples)));
 
         /// <summary>
         /// Tests that when a normal sample bank is used, the normal hitsound will be looked up.

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

@@ -2,7 +2,7 @@
   <Import Project="..\osu.TestProject.props" />
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

osu.Game.Rulesets.Mania/Difficulty/ManiaDifficultyCalculator.cs

@@ -68,7 +68,7 @@ namespace osu.Game.Rulesets.Mania.Difficulty
         // Sorting is done in CreateDifficultyHitObjects, since the full list of hitobjects is required.
         protected override IEnumerable<DifficultyHitObject> SortObjects(IEnumerable<DifficultyHitObject> input) => input;
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[]
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[]
         {
             new Strain(mods, ((ManiaBeatmap)beatmap).TotalColumns)
         };

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

@@ -4,7 +4,6 @@
 using System.Collections.Generic;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mania.Beatmaps;
-using osu.Game.Rulesets.Mania.Objects;
 using osu.Game.Rulesets.Mania.Replays;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Scoring;
@@ -12,7 +11,7 @@ using osu.Game.Users;
 
 namespace osu.Game.Rulesets.Mania.Mods
 {
-    public class ManiaModAutoplay : ModAutoplay<ManiaHitObject>
+    public class ManiaModAutoplay : ModAutoplay
     {
         public override Score CreateReplayScore(IBeatmap beatmap, IReadOnlyList<Mod> mods) => new Score
         {

osu.Game.Rulesets.Mania/Mods/ManiaModRandom.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.Extensions.IEnumerableExtensions;
 using osu.Framework.Utils;
@@ -17,8 +18,11 @@ namespace osu.Game.Rulesets.Mania.Mods
 
         public void ApplyToBeatmap(IBeatmap beatmap)
         {
+            Seed.Value ??= RNG.Next();
+            var rng = new Random((int)Seed.Value);
+
             var availableColumns = ((ManiaBeatmap)beatmap).TotalColumns;
-            var shuffledColumns = Enumerable.Range(0, availableColumns).OrderBy(item => RNG.Next()).ToList();
+            var shuffledColumns = Enumerable.Range(0, availableColumns).OrderBy(item => rng.Next()).ToList();
 
             beatmap.HitObjects.OfType<ManiaHitObject>().ForEach(h => h.Column = shuffledColumns[h.Column]);
         }

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

@@ -69,10 +69,10 @@ namespace osu.Game.Rulesets.Mania.Skinning.Legacy
 
         private void sourceChanged()
         {
-            isLegacySkin = new Lazy<bool>(() => Source.GetConfig<LegacySkinConfiguration.LegacySetting, decimal>(LegacySkinConfiguration.LegacySetting.Version) != null);
+            isLegacySkin = new Lazy<bool>(() => FindProvider(s => s.GetConfig<LegacySkinConfiguration.LegacySetting, decimal>(LegacySkinConfiguration.LegacySetting.Version) != null) != null);
-            hasKeyTexture = new Lazy<bool>(() => Source.GetAnimation(
+            hasKeyTexture = new Lazy<bool>(() => FindProvider(s => s.GetAnimation(
-                this.GetManiaSkinConfig<string>(LegacyManiaSkinConfigurationLookups.KeyImage, 0)?.Value
+                s.GetManiaSkinConfig<string>(LegacyManiaSkinConfigurationLookups.KeyImage, 0)?.Value
-                ?? "mania-key1", true, true) != null);
+                ?? "mania-key1", true, true) != null) != null);
         }
 
         public override Drawable GetDrawableComponent(ISkinComponent component)
@@ -125,7 +125,7 @@ namespace osu.Game.Rulesets.Mania.Skinning.Legacy
                     break;
             }
 
-            return null;
+            return Source.GetDrawableComponent(component);
         }
 
         private Drawable getResult(HitResult result)

osu.Game.Rulesets.Mania/UI/Components/HitObjectArea.cs

@@ -33,9 +33,9 @@ namespace osu.Game.Rulesets.Mania.UI.Components
             Direction.BindValueChanged(onDirectionChanged, true);
         }
 
-        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        protected override void SkinChanged(ISkinSource skin)
         {
-            base.SkinChanged(skin, allowFallback);
+            base.SkinChanged(skin);
             UpdateHitPosition();
         }
 

osu.Game.Rulesets.Osu.Tests/Resources/SampleLookups/osu-hitobject-beatmap-custom-sample-bank.osu

@@ -0,0 +1,10 @@
+osu file format v14
+
+[General]
+Mode: 0
+
+[TimingPoints]
+0,300,4,1,2,100,1,0
+
+[HitObjects]
+444,320,1000,5,0,0:0:0:0:

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

@@ -39,18 +39,28 @@ namespace osu.Game.Rulesets.Osu.Tests
         [Test]
         public void TestLegacySmoothCursorTrail()
         {
-            createTest(() => new LegacySkinContainer(false)
+            createTest(() =>
             {
-                Child = new LegacyCursorTrail()
+                var skinContainer = new LegacySkinContainer(false);
+                var legacyCursorTrail = new LegacyCursorTrail(skinContainer);
+
+                skinContainer.Child = legacyCursorTrail;
+
+                return skinContainer;
             });
         }
 
         [Test]
         public void TestLegacyDisjointCursorTrail()
         {
-            createTest(() => new LegacySkinContainer(true)
+            createTest(() =>
             {
-                Child = new LegacyCursorTrail()
+                var skinContainer = new LegacySkinContainer(true);
+                var legacyCursorTrail = new LegacyCursorTrail(skinContainer);
+
+                skinContainer.Child = legacyCursorTrail;
+
+                return skinContainer;
             });
         }
 
@@ -102,6 +112,8 @@ namespace osu.Game.Rulesets.Osu.Tests
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => null;
 
+            public ISkin FindProvider(Func<ISkin, bool> lookupFunction) => null;
+
             public event Action SourceChanged
             {
                 add { }

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

@@ -64,7 +64,7 @@ namespace osu.Game.Rulesets.Osu.Tests
             {
                 int poolIndex = 0;
 
-                SetContents(() =>
+                SetContents(_ =>
                 {
                     DrawablePool<TestDrawableOsuJudgement> pool;
 

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

@@ -97,7 +97,7 @@ namespace osu.Game.Rulesets.Osu.Tests
 
         private void loadContent(bool automated = true, Func<SkinProvidingContainer> skinProvider = null)
         {
-            SetContents(() =>
+            SetContents(_ =>
             {
                 var inputManager = automated ? (InputManager)new MovingCursorInputManager() : new OsuInputManager(new OsuRuleset().RulesetInfo);
                 var skinContainer = skinProvider?.Invoke() ?? new SkinProvidingContainer(null);
@@ -113,6 +113,7 @@ namespace osu.Game.Rulesets.Osu.Tests
             public Drawable GetDrawableComponent(ISkinComponent component) => null;
             public Texture GetTexture(string componentName, WrapMode wrapModeS, WrapMode wrapModeT) => null;
             public ISample GetSample(ISampleInfo sampleInfo) => null;
+            public ISkin FindProvider(Func<ISkin, bool> lookupFunction) => null;
 
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup)
             {

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

@@ -23,18 +23,18 @@ namespace osu.Game.Rulesets.Osu.Tests
         [Test]
         public void TestVariousHitCircles()
         {
-            AddStep("Miss Big Single", () => SetContents(() => testSingle(2)));
+            AddStep("Miss Big Single", () => SetContents(_ => testSingle(2)));
-            AddStep("Miss Medium Single", () => SetContents(() => testSingle(5)));
+            AddStep("Miss Medium Single", () => SetContents(_ => testSingle(5)));
-            AddStep("Miss Small Single", () => SetContents(() => testSingle(7)));
+            AddStep("Miss Small Single", () => SetContents(_ => testSingle(7)));
-            AddStep("Hit Big Single", () => SetContents(() => testSingle(2, true)));
+            AddStep("Hit Big Single", () => SetContents(_ => testSingle(2, true)));
-            AddStep("Hit Medium Single", () => SetContents(() => testSingle(5, true)));
+            AddStep("Hit Medium Single", () => SetContents(_ => testSingle(5, true)));
-            AddStep("Hit Small Single", () => SetContents(() => testSingle(7, true)));
+            AddStep("Hit Small Single", () => SetContents(_ => testSingle(7, true)));
-            AddStep("Miss Big Stream", () => SetContents(() => testStream(2)));
+            AddStep("Miss Big Stream", () => SetContents(_ => testStream(2)));
-            AddStep("Miss Medium Stream", () => SetContents(() => testStream(5)));
+            AddStep("Miss Medium Stream", () => SetContents(_ => testStream(5)));
-            AddStep("Miss Small Stream", () => SetContents(() => testStream(7)));
+            AddStep("Miss Small Stream", () => SetContents(_ => testStream(7)));
-            AddStep("Hit Big Stream", () => SetContents(() => testStream(2, true)));
+            AddStep("Hit Big Stream", () => SetContents(_ => testStream(2, true)));
-            AddStep("Hit Medium Stream", () => SetContents(() => testStream(5, true)));
+            AddStep("Hit Medium Stream", () => SetContents(_ => testStream(5, true)));
-            AddStep("Hit Small Stream", () => SetContents(() => testStream(7, true)));
+            AddStep("Hit Small Stream", () => SetContents(_ => testStream(7, true)));
         }
 
         private Drawable testSingle(float circleSize, bool auto = false, double timeOffset = 0, Vector2? positionOffset = null)

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

@@ -0,0 +1,30 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using NUnit.Framework;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+
+namespace osu.Game.Rulesets.Osu.Tests
+{
+    [TestFixture]
+    public class TestSceneHitCircleKiai : TestSceneHitCircle
+    {
+        [SetUp]
+        public void SetUp() => Schedule(() =>
+        {
+            var controlPointInfo = new ControlPointInfo();
+
+            controlPointInfo.Add(0, new TimingControlPoint { BeatLength = 500 });
+            controlPointInfo.Add(0, new EffectControlPoint { KiaiMode = true });
+
+            Beatmap.Value = CreateWorkingBeatmap(new Beatmap
+            {
+                ControlPointInfo = controlPointInfo
+            });
+
+            // track needs to be playing for BeatSyncedContainer to work.
+            Beatmap.Value.Track.Start();
+        });
+    }
+}

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

@@ -30,28 +30,28 @@ namespace osu.Game.Rulesets.Osu.Tests
         [TestCase(true, false)]
         [TestCase(false, true)]
         [TestCase(false, false)]
-        public override void TestBeatmapComboColours(bool userHasCustomColours, bool useBeatmapSkin)
+        public void TestBeatmapComboColours(bool userHasCustomColours, bool useBeatmapSkin)
         {
-            TestBeatmap = new OsuCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new OsuCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColours(userHasCustomColours, useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, true, userHasCustomColours);
             AddAssert("is beatmap skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestBeatmapSkin.Colours));
         }
 
         [TestCase(true)]
         [TestCase(false)]
-        public override void TestBeatmapComboColoursOverride(bool useBeatmapSkin)
+        public void TestBeatmapComboColoursOverride(bool useBeatmapSkin)
         {
-            TestBeatmap = new OsuCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new OsuCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColoursOverride(useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, false, true);
             AddAssert("is user custom skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestSkin.Colours));
         }
 
         [TestCase(true)]
         [TestCase(false)]
-        public override void TestBeatmapComboColoursOverrideWithDefaultColours(bool useBeatmapSkin)
+        public void TestBeatmapComboColoursOverrideWithDefaultColours(bool useBeatmapSkin)
         {
-            TestBeatmap = new OsuCustomSkinWorkingBeatmap(audio, true);
+            PrepareBeatmap(() => new OsuCustomSkinWorkingBeatmap(audio, true));
-            base.TestBeatmapComboColoursOverrideWithDefaultColours(useBeatmapSkin);
+            ConfigureTest(useBeatmapSkin, false, false);
             AddAssert("is default user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(SkinConfiguration.DefaultComboColours));
         }
 
@@ -59,10 +59,10 @@ namespace osu.Game.Rulesets.Osu.Tests
         [TestCase(false, true)]
         [TestCase(true, false)]
         [TestCase(false, false)]
-        public override void TestBeatmapNoComboColours(bool useBeatmapSkin, bool useBeatmapColour)
+        public void TestBeatmapNoComboColours(bool useBeatmapSkin, bool useBeatmapColour)
         {
-            TestBeatmap = new OsuCustomSkinWorkingBeatmap(audio, false);
+            PrepareBeatmap(() => new OsuCustomSkinWorkingBeatmap(audio, false));
-            base.TestBeatmapNoComboColours(useBeatmapSkin, useBeatmapColour);
+            ConfigureTest(useBeatmapSkin, useBeatmapColour, false);
             AddAssert("is default user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(SkinConfiguration.DefaultComboColours));
         }
 
@@ -70,10 +70,10 @@ namespace osu.Game.Rulesets.Osu.Tests
         [TestCase(false, true)]
         [TestCase(true, false)]
         [TestCase(false, false)]
-        public override void TestBeatmapNoComboColoursSkinOverride(bool useBeatmapSkin, bool useBeatmapColour)
+        public void TestBeatmapNoComboColoursSkinOverride(bool useBeatmapSkin, bool useBeatmapColour)
         {
-            TestBeatmap = new OsuCustomSkinWorkingBeatmap(audio, false);
+            PrepareBeatmap(() => new OsuCustomSkinWorkingBeatmap(audio, false));
-            base.TestBeatmapNoComboColoursSkinOverride(useBeatmapSkin, useBeatmapColour);
+            ConfigureTest(useBeatmapSkin, useBeatmapColour, true);
             AddAssert("is custom user skin colours", () => TestPlayer.UsableComboColours.SequenceEqual(TestSkin.Colours));
         }
 

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

@@ -0,0 +1,49 @@
+// 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.Reflection;
+using NUnit.Framework;
+using osu.Framework.IO.Stores;
+using osu.Game.Tests.Beatmaps;
+
+namespace osu.Game.Rulesets.Osu.Tests
+{
+    public class TestSceneOsuHitObjectSamples : HitObjectSampleTest
+    {
+        protected override Ruleset CreatePlayerRuleset() => new OsuRuleset();
+
+        protected override IResourceStore<byte[]> RulesetResources => new DllResourceStore(Assembly.GetAssembly(typeof(TestSceneOsuHitObjectSamples)));
+
+        [TestCase("normal-hitnormal")]
+        [TestCase("hitnormal")]
+        public void TestDefaultCustomSampleFromBeatmap(string expectedSample)
+        {
+            SetupSkins(expectedSample, expectedSample);
+
+            CreateTestWithBeatmap("osu-hitobject-beatmap-custom-sample-bank.osu");
+
+            AssertBeatmapLookup(expectedSample);
+        }
+
+        [TestCase("normal-hitnormal")]
+        [TestCase("hitnormal")]
+        public void TestDefaultCustomSampleFromUserSkinFallback(string expectedSample)
+        {
+            SetupSkins(string.Empty, expectedSample);
+
+            CreateTestWithBeatmap("osu-hitobject-beatmap-custom-sample-bank.osu");
+
+            AssertUserLookup(expectedSample);
+        }
+
+        [TestCase("normal-hitnormal2")]
+        public void TestUserSkinLookupIgnoresSampleBank(string unwantedSample)
+        {
+            SetupSkins(string.Empty, unwantedSample);
+
+            CreateTestWithBeatmap("osu-hitobject-beatmap-custom-sample-bank.osu");
+
+            AssertNoLookup(unwantedSample);
+        }
+    }
+}

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

@@ -166,6 +166,7 @@ namespace osu.Game.Rulesets.Osu.Tests
 
             public TValue GetValue<TConfiguration, TValue>(Func<TConfiguration, TValue> query) where TConfiguration : SkinConfiguration => default;
             public IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup) => null;
+            public ISkin FindProvider(Func<ISkin, bool> lookupFunction) => null;
 
             public event Action SourceChanged;
 

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

@@ -30,54 +30,54 @@ namespace osu.Game.Rulesets.Osu.Tests
         [Test]
         public void TestVariousSliders()
         {
-            AddStep("Big Single", () => SetContents(() => testSimpleBig()));
+            AddStep("Big Single", () => SetContents(_ => testSimpleBig()));
-            AddStep("Medium Single", () => SetContents(() => testSimpleMedium()));
+            AddStep("Medium Single", () => SetContents(_ => testSimpleMedium()));
-            AddStep("Small Single", () => SetContents(() => testSimpleSmall()));
+            AddStep("Small Single", () => SetContents(_ => testSimpleSmall()));
-            AddStep("Big 1 Repeat", () => SetContents(() => testSimpleBig(1)));
+            AddStep("Big 1 Repeat", () => SetContents(_ => testSimpleBig(1)));
-            AddStep("Medium 1 Repeat", () => SetContents(() => testSimpleMedium(1)));
+            AddStep("Medium 1 Repeat", () => SetContents(_ => testSimpleMedium(1)));
-            AddStep("Small 1 Repeat", () => SetContents(() => testSimpleSmall(1)));
+            AddStep("Small 1 Repeat", () => SetContents(_ => testSimpleSmall(1)));
-            AddStep("Big 2 Repeats", () => SetContents(() => testSimpleBig(2)));
+            AddStep("Big 2 Repeats", () => SetContents(_ => testSimpleBig(2)));
-            AddStep("Medium 2 Repeats", () => SetContents(() => testSimpleMedium(2)));
+            AddStep("Medium 2 Repeats", () => SetContents(_ => testSimpleMedium(2)));
-            AddStep("Small 2 Repeats", () => SetContents(() => testSimpleSmall(2)));
+            AddStep("Small 2 Repeats", () => SetContents(_ => testSimpleSmall(2)));
 
-            AddStep("Slow Slider", () => SetContents(testSlowSpeed)); // slow long sliders take ages already so no repeat steps
+            AddStep("Slow Slider", () => SetContents(_ => testSlowSpeed())); // slow long sliders take ages already so no repeat steps
-            AddStep("Slow Short Slider", () => SetContents(() => testShortSlowSpeed()));
+            AddStep("Slow Short Slider", () => SetContents(_ => testShortSlowSpeed()));
-            AddStep("Slow Short Slider 1 Repeats", () => SetContents(() => testShortSlowSpeed(1)));
+            AddStep("Slow Short Slider 1 Repeats", () => SetContents(_ => testShortSlowSpeed(1)));
-            AddStep("Slow Short Slider 2 Repeats", () => SetContents(() => testShortSlowSpeed(2)));
+            AddStep("Slow Short Slider 2 Repeats", () => SetContents(_ => testShortSlowSpeed(2)));
 
-            AddStep("Fast Slider", () => SetContents(() => testHighSpeed()));
+            AddStep("Fast Slider", () => SetContents(_ => testHighSpeed()));
-            AddStep("Fast Slider 1 Repeat", () => SetContents(() => testHighSpeed(1)));
+            AddStep("Fast Slider 1 Repeat", () => SetContents(_ => testHighSpeed(1)));
-            AddStep("Fast Slider 2 Repeats", () => SetContents(() => testHighSpeed(2)));
+            AddStep("Fast Slider 2 Repeats", () => SetContents(_ => testHighSpeed(2)));
-            AddStep("Fast Short Slider", () => SetContents(() => testShortHighSpeed()));
+            AddStep("Fast Short Slider", () => SetContents(_ => testShortHighSpeed()));
-            AddStep("Fast Short Slider 1 Repeat", () => SetContents(() => testShortHighSpeed(1)));
+            AddStep("Fast Short Slider 1 Repeat", () => SetContents(_ => testShortHighSpeed(1)));
-            AddStep("Fast Short Slider 2 Repeats", () => SetContents(() => testShortHighSpeed(2)));
+            AddStep("Fast Short Slider 2 Repeats", () => SetContents(_ => testShortHighSpeed(2)));
-            AddStep("Fast Short Slider 6 Repeats", () => SetContents(() => testShortHighSpeed(6)));
+            AddStep("Fast Short Slider 6 Repeats", () => SetContents(_ => testShortHighSpeed(6)));
 
-            AddStep("Perfect Curve", () => SetContents(() => testPerfect()));
+            AddStep("Perfect Curve", () => SetContents(_ => testPerfect()));
-            AddStep("Perfect Curve 1 Repeat", () => SetContents(() => testPerfect(1)));
+            AddStep("Perfect Curve 1 Repeat", () => SetContents(_ => testPerfect(1)));
-            AddStep("Perfect Curve 2 Repeats", () => SetContents(() => testPerfect(2)));
+            AddStep("Perfect Curve 2 Repeats", () => SetContents(_ => testPerfect(2)));
 
-            AddStep("Linear Slider", () => SetContents(() => testLinear()));
+            AddStep("Linear Slider", () => SetContents(_ => testLinear()));
-            AddStep("Linear Slider 1 Repeat", () => SetContents(() => testLinear(1)));
+            AddStep("Linear Slider 1 Repeat", () => SetContents(_ => testLinear(1)));
-            AddStep("Linear Slider 2 Repeats", () => SetContents(() => testLinear(2)));
+            AddStep("Linear Slider 2 Repeats", () => SetContents(_ => testLinear(2)));
 
-            AddStep("Bezier Slider", () => SetContents(() => testBezier()));
+            AddStep("Bezier Slider", () => SetContents(_ => testBezier()));
-            AddStep("Bezier Slider 1 Repeat", () => SetContents(() => testBezier(1)));
+            AddStep("Bezier Slider 1 Repeat", () => SetContents(_ => testBezier(1)));
-            AddStep("Bezier Slider 2 Repeats", () => SetContents(() => testBezier(2)));
+            AddStep("Bezier Slider 2 Repeats", () => SetContents(_ => testBezier(2)));
 
-            AddStep("Linear Overlapping", () => SetContents(() => testLinearOverlapping()));
+            AddStep("Linear Overlapping", () => SetContents(_ => testLinearOverlapping()));
-            AddStep("Linear Overlapping 1 Repeat", () => SetContents(() => testLinearOverlapping(1)));
+            AddStep("Linear Overlapping 1 Repeat", () => SetContents(_ => testLinearOverlapping(1)));
-            AddStep("Linear Overlapping 2 Repeats", () => SetContents(() => testLinearOverlapping(2)));
+            AddStep("Linear Overlapping 2 Repeats", () => SetContents(_ => testLinearOverlapping(2)));
 
-            AddStep("Catmull Slider", () => SetContents(() => testCatmull()));
+            AddStep("Catmull Slider", () => SetContents(_ => testCatmull()));
-            AddStep("Catmull Slider 1 Repeat", () => SetContents(() => testCatmull(1)));
+            AddStep("Catmull Slider 1 Repeat", () => SetContents(_ => testCatmull(1)));
-            AddStep("Catmull Slider 2 Repeats", () => SetContents(() => testCatmull(2)));
+            AddStep("Catmull Slider 2 Repeats", () => SetContents(_ => testCatmull(2)));
 
-            AddStep("Big Single, Large StackOffset", () => SetContents(() => testSimpleBigLargeStackOffset()));
+            AddStep("Big Single, Large StackOffset", () => SetContents(_ => testSimpleBigLargeStackOffset()));
-            AddStep("Big 1 Repeat, Large StackOffset", () => SetContents(() => testSimpleBigLargeStackOffset(1)));
+            AddStep("Big 1 Repeat, Large StackOffset", () => SetContents(_ => testSimpleBigLargeStackOffset(1)));
 
-            AddStep("Distance Overflow", () => SetContents(() => testDistanceOverflow()));
+            AddStep("Distance Overflow", () => SetContents(_ => testDistanceOverflow()));
-            AddStep("Distance Overflow 1 Repeat", () => SetContents(() => testDistanceOverflow(1)));
+            AddStep("Distance Overflow 1 Repeat", () => SetContents(_ => testDistanceOverflow(1)));
         }
 
         [Test]

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

@@ -29,15 +29,15 @@ namespace osu.Game.Rulesets.Osu.Tests
         public void TestVariousSpinners(bool autoplay)
         {
             string term = autoplay ? "Hit" : "Miss";
-            AddStep($"{term} Big", () => SetContents(() => testSingle(2, autoplay)));
+            AddStep($"{term} Big", () => SetContents(_ => testSingle(2, autoplay)));
-            AddStep($"{term} Medium", () => SetContents(() => testSingle(5, autoplay)));
+            AddStep($"{term} Medium", () => SetContents(_ => testSingle(5, autoplay)));
-            AddStep($"{term} Small", () => SetContents(() => testSingle(7, autoplay)));
+            AddStep($"{term} Small", () => SetContents(_ => testSingle(7, autoplay)));
         }
 
         [Test]
         public void TestSpinningSamplePitchShift()
         {
-            AddStep("Add spinner", () => SetContents(() => testSingle(5, true, 4000)));
+            AddStep("Add spinner", () => SetContents(_ => testSingle(5, true, 4000)));
             AddUntilStep("Pitch starts low", () => getSpinningSample().Frequency.Value < 0.8);
             AddUntilStep("Pitch increases", () => getSpinningSample().Frequency.Value > 0.8);
 
@@ -48,7 +48,7 @@ namespace osu.Game.Rulesets.Osu.Tests
         [TestCase(true)]
         public void TestLongSpinner(bool autoplay)
         {
-            AddStep("Very long spinner", () => SetContents(() => testSingle(5, autoplay, 4000)));
+            AddStep("Very long spinner", () => SetContents(_ => testSingle(5, autoplay, 4000)));
             AddUntilStep("Wait for completion", () => drawableSpinner.Result.HasResult);
             AddUntilStep("Check correct progress", () => drawableSpinner.Progress == (autoplay ? 1 : 0));
         }
@@ -57,7 +57,7 @@ namespace osu.Game.Rulesets.Osu.Tests
         [TestCase(true)]
         public void TestSuperShortSpinner(bool autoplay)
         {
-            AddStep("Very short spinner", () => SetContents(() => testSingle(5, autoplay, 200)));
+            AddStep("Very short spinner", () => SetContents(_ => testSingle(5, autoplay, 200)));
             AddUntilStep("Wait for completion", () => drawableSpinner.Result.HasResult);
             AddUntilStep("Short spinner implicitly completes", () => drawableSpinner.Progress == 1);
         }

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

@@ -2,7 +2,7 @@
   <Import Project="..\osu.TestProject.props" />
   <ItemGroup Label="Package References">
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.9.4" />
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
     <PackageReference Include="NUnit" Version="3.13.2" />
     <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />

osu.Game.Rulesets.Osu/Difficulty/OsuDifficultyCalculator.cs

@@ -79,7 +79,7 @@ namespace osu.Game.Rulesets.Osu.Difficulty
             }
         }
 
-        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods) => new Skill[]
+        protected override Skill[] CreateSkills(IBeatmap beatmap, Mod[] mods, double clockRate) => new Skill[]
         {
             new Aim(mods),
             new Speed(mods)

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

@@ -6,14 +6,13 @@ using System.Collections.Generic;
 using System.Linq;
 using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Mods;
-using osu.Game.Rulesets.Osu.Objects;
 using osu.Game.Rulesets.Osu.Replays;
 using osu.Game.Scoring;
 using osu.Game.Users;
 
 namespace osu.Game.Rulesets.Osu.Mods
 {
-    public class OsuModAutoplay : ModAutoplay<OsuHitObject>
+    public class OsuModAutoplay : ModAutoplay
     {
         public override Type[] IncompatibleMods => base.IncompatibleMods.Append(typeof(OsuModAutopilot)).Append(typeof(OsuModSpunOut)).ToArray();
 

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

@@ -0,0 +1,274 @@
+// 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.Framework.Graphics;
+using osu.Framework.Utils;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Osu.Beatmaps;
+using osu.Game.Rulesets.Osu.Objects;
+using osu.Game.Rulesets.Osu.UI;
+using osuTK;
+
+namespace osu.Game.Rulesets.Osu.Mods
+{
+    /// <summary>
+    /// Mod that randomises the positions of the <see cref="HitObject"/>s
+    /// </summary>
+    public class OsuModRandom : ModRandom, IApplicableToBeatmap
+    {
+        public override string Description => "It never gets boring!";
+        public override bool Ranked => false;
+
+        // The relative distance to the edge of the playfield before objects' positions should start to "turn around" and curve towards the middle.
+        // The closer the hit objects draw to the border, the sharper the turn
+        private const float playfield_edge_ratio = 0.375f;
+
+        private static readonly float border_distance_x = OsuPlayfield.BASE_SIZE.X * playfield_edge_ratio;
+        private static readonly float border_distance_y = OsuPlayfield.BASE_SIZE.Y * playfield_edge_ratio;
+
+        private static readonly Vector2 playfield_middle = OsuPlayfield.BASE_SIZE / 2;
+
+        private static readonly float playfield_diagonal = OsuPlayfield.BASE_SIZE.LengthFast;
+
+        private Random rng;
+
+        public void ApplyToBeatmap(IBeatmap beatmap)
+        {
+            if (!(beatmap is OsuBeatmap osuBeatmap))
+                return;
+
+            var hitObjects = osuBeatmap.HitObjects;
+
+            Seed.Value ??= RNG.Next();
+
+            rng = new Random((int)Seed.Value);
+
+            RandomObjectInfo previous = null;
+
+            float rateOfChangeMultiplier = 0;
+
+            for (int i = 0; i < hitObjects.Count; i++)
+            {
+                var hitObject = hitObjects[i];
+
+                var current = new RandomObjectInfo(hitObject);
+
+                // rateOfChangeMultiplier only changes every i iterations to prevent shaky-line-shaped streams
+                if (i % 3 == 0)
+                    rateOfChangeMultiplier = (float)rng.NextDouble() * 2 - 1;
+
+                if (hitObject is Spinner)
+                {
+                    previous = null;
+                    continue;
+                }
+
+                applyRandomisation(rateOfChangeMultiplier, previous, current);
+
+                hitObject.Position = current.PositionRandomised;
+
+                // update end position as it may have changed as a result of the position update.
+                current.EndPositionRandomised = current.PositionRandomised;
+
+                if (hitObject is Slider slider)
+                    moveSliderIntoPlayfield(slider, current);
+
+                previous = current;
+            }
+        }
+
+        /// <summary>
+        /// Returns the final position of the hit object
+        /// </summary>
+        /// <returns>Final position of the hit object</returns>
+        private void applyRandomisation(float rateOfChangeMultiplier, RandomObjectInfo previous, RandomObjectInfo current)
+        {
+            if (previous == null)
+            {
+                var playfieldSize = OsuPlayfield.BASE_SIZE;
+
+                current.AngleRad = (float)(rng.NextDouble() * 2 * Math.PI - Math.PI);
+                current.PositionRandomised = new Vector2((float)rng.NextDouble() * playfieldSize.X, (float)rng.NextDouble() * playfieldSize.Y);
+
+                return;
+            }
+
+            float distanceToPrev = Vector2.Distance(previous.EndPositionOriginal, current.PositionOriginal);
+
+            // The max. angle (relative to the angle of the vector pointing from the 2nd last to the last hit object)
+            // is proportional to the distance between the last and the current hit object
+            // to allow jumps and prevent too sharp turns during streams.
+            var randomAngleRad = rateOfChangeMultiplier * 2 * Math.PI * distanceToPrev / playfield_diagonal;
+
+            current.AngleRad = (float)randomAngleRad + previous.AngleRad;
+            if (current.AngleRad < 0)
+                current.AngleRad += 2 * (float)Math.PI;
+
+            var posRelativeToPrev = new Vector2(
+                distanceToPrev * (float)Math.Cos(current.AngleRad),
+                distanceToPrev * (float)Math.Sin(current.AngleRad)
+            );
+
+            posRelativeToPrev = getRotatedVector(previous.EndPositionRandomised, posRelativeToPrev);
+
+            current.AngleRad = (float)Math.Atan2(posRelativeToPrev.Y, posRelativeToPrev.X);
+
+            var position = previous.EndPositionRandomised + posRelativeToPrev;
+
+            // Move hit objects back into the playfield if they are outside of it,
+            // which would sometimes happen during big jumps otherwise.
+            position.X = MathHelper.Clamp(position.X, 0, OsuPlayfield.BASE_SIZE.X);
+            position.Y = MathHelper.Clamp(position.Y, 0, OsuPlayfield.BASE_SIZE.Y);
+
+            current.PositionRandomised = position;
+        }
+
+        /// <summary>
+        /// Moves the <see cref="Slider"/> and all necessary nested <see cref="OsuHitObject"/>s into the <see cref="OsuPlayfield"/> if they aren't already.
+        /// </summary>
+        private void moveSliderIntoPlayfield(Slider slider, RandomObjectInfo currentObjectInfo)
+        {
+            var minMargin = getMinSliderMargin(slider);
+
+            slider.Position = new Vector2(
+                Math.Clamp(slider.Position.X, minMargin.Left, OsuPlayfield.BASE_SIZE.X - minMargin.Right),
+                Math.Clamp(slider.Position.Y, minMargin.Top, OsuPlayfield.BASE_SIZE.Y - minMargin.Bottom)
+            );
+
+            currentObjectInfo.PositionRandomised = slider.Position;
+            currentObjectInfo.EndPositionRandomised = slider.EndPosition;
+
+            shiftNestedObjects(slider, currentObjectInfo.PositionRandomised - currentObjectInfo.PositionOriginal);
+        }
+
+        /// <summary>
+        /// Calculates the min. distances from the <see cref="Slider"/>'s position to the playfield border for the slider to be fully inside of the playfield.
+        /// </summary>
+        private MarginPadding getMinSliderMargin(Slider slider)
+        {
+            var pathPositions = new List<Vector2>();
+            slider.Path.GetPathToProgress(pathPositions, 0, 1);
+
+            var minMargin = new MarginPadding();
+
+            foreach (var pos in pathPositions)
+            {
+                minMargin.Left = Math.Max(minMargin.Left, -pos.X);
+                minMargin.Right = Math.Max(minMargin.Right, pos.X);
+                minMargin.Top = Math.Max(minMargin.Top, -pos.Y);
+                minMargin.Bottom = Math.Max(minMargin.Bottom, pos.Y);
+            }
+
+            minMargin.Left = Math.Min(minMargin.Left, OsuPlayfield.BASE_SIZE.X - minMargin.Right);
+            minMargin.Top = Math.Min(minMargin.Top, OsuPlayfield.BASE_SIZE.Y - minMargin.Bottom);
+
+            return minMargin;
+        }
+
+        /// <summary>
+        /// Shifts all nested <see cref="SliderTick"/>s and <see cref="SliderRepeat"/>s by the specified shift.
+        /// </summary>
+        /// <param name="slider"><see cref="Slider"/> whose nested <see cref="SliderTick"/>s and <see cref="SliderRepeat"/>s should be shifted</param>
+        /// <param name="shift">The <see cref="Vector2"/> the <see cref="Slider"/>'s nested <see cref="SliderTick"/>s and <see cref="SliderRepeat"/>s should be shifted by</param>
+        private void shiftNestedObjects(Slider slider, Vector2 shift)
+        {
+            foreach (var hitObject in slider.NestedHitObjects.Where(o => o is SliderTick || o is SliderRepeat))
+            {
+                if (!(hitObject is OsuHitObject osuHitObject))
+                    continue;
+
+                osuHitObject.Position += shift;
+            }
+        }
+
+        /// <summary>
+        /// Determines the position of the current hit object relative to the previous one.
+        /// </summary>
+        /// <returns>The position of the current hit object relative to the previous one</returns>
+        private Vector2 getRotatedVector(Vector2 prevPosChanged, Vector2 posRelativeToPrev)
+        {
+            var relativeRotationDistance = 0f;
+
+            if (prevPosChanged.X < playfield_middle.X)
+            {
+                relativeRotationDistance = Math.Max(
+                    (border_distance_x - prevPosChanged.X) / border_distance_x,
+                    relativeRotationDistance
+                );
+            }
+            else
+            {
+                relativeRotationDistance = Math.Max(
+                    (prevPosChanged.X - (OsuPlayfield.BASE_SIZE.X - border_distance_x)) / border_distance_x,
+                    relativeRotationDistance
+                );
+            }
+
+            if (prevPosChanged.Y < playfield_middle.Y)
+            {
+                relativeRotationDistance = Math.Max(
+                    (border_distance_y - prevPosChanged.Y) / border_distance_y,
+                    relativeRotationDistance
+                );
+            }
+            else
+            {
+                relativeRotationDistance = Math.Max(
+                    (prevPosChanged.Y - (OsuPlayfield.BASE_SIZE.Y - border_distance_y)) / border_distance_y,
+                    relativeRotationDistance
+                );
+            }
+
+            return rotateVectorTowardsVector(posRelativeToPrev, playfield_middle - prevPosChanged, relativeRotationDistance / 2);
+        }
+
+        /// <summary>
+        /// Rotates vector "initial" towards vector "destinantion"
+        /// </summary>
+        /// <param name="initial">Vector to rotate to "destination"</param>
+        /// <param name="destination">Vector "initial" should be rotated to</param>
+        /// <param name="relativeDistance">The angle the vector should be rotated relative to the difference between the angles of the the two vectors.</param>
+        /// <returns>Resulting vector</returns>
+        private Vector2 rotateVectorTowardsVector(Vector2 initial, Vector2 destination, float relativeDistance)
+        {
+            var initialAngleRad = Math.Atan2(initial.Y, initial.X);
+            var destAngleRad = Math.Atan2(destination.Y, destination.X);
+
+            var diff = destAngleRad - initialAngleRad;
+
+            while (diff < -Math.PI) diff += 2 * Math.PI;
+
+            while (diff > Math.PI) diff -= 2 * Math.PI;
+
+            var finalAngleRad = initialAngleRad + relativeDistance * diff;
+
+            return new Vector2(
+                initial.Length * (float)Math.Cos(finalAngleRad),
+                initial.Length * (float)Math.Sin(finalAngleRad)
+            );
+        }
+
+        private class RandomObjectInfo
+        {
+            public float AngleRad { get; set; }
+
+            public Vector2 PositionOriginal { get; }
+            public Vector2 PositionRandomised { get; set; }
+
+            public Vector2 EndPositionOriginal { get; }
+            public Vector2 EndPositionRandomised { get; set; }
+
+            public RandomObjectInfo(OsuHitObject hitObject)
+            {
+                PositionRandomised = PositionOriginal = hitObject.Position;
+                EndPositionRandomised = EndPositionOriginal = hitObject.EndPosition;
+                AngleRad = 0;
+            }
+        }
+    }
+}

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

@@ -5,6 +5,7 @@ using System;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Pooling;
 using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Pooling;
 using osuTK;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
@@ -12,34 +13,29 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
     /// <summary>
     /// Visualises the <see cref="FollowPoint"/>s between two <see cref="DrawableOsuHitObject"/>s.
     /// </summary>
-    public class FollowPointConnection : PoolableDrawable
+    public class FollowPointConnection : PoolableDrawableWithLifetime<FollowPointLifetimeEntry>
     {
         // Todo: These shouldn't be constants
         public const int SPACING = 32;
         public const double PREEMPT = 800;
 
-        public FollowPointLifetimeEntry Entry;
         public DrawablePool<FollowPoint> Pool;
 
-        protected override void PrepareForUse()
+        protected override void OnApply(FollowPointLifetimeEntry entry)
         {
-            base.PrepareForUse();
+            base.OnApply(entry);
-
-            Entry.Invalidated += onEntryInvalidated;
 
+            entry.Invalidated += onEntryInvalidated;
             refreshPoints();
         }
 
-        protected override void FreeAfterUse()
+        protected override void OnFree(FollowPointLifetimeEntry entry)
         {
-            base.FreeAfterUse();
+            base.OnFree(entry);
-
-            Entry.Invalidated -= onEntryInvalidated;
 
+            entry.Invalidated -= onEntryInvalidated;
             // Return points to the pool.
             ClearInternal(false);
-
-            Entry = null;
         }
 
         private void onEntryInvalidated() => Scheduler.AddOnce(refreshPoints);
@@ -48,8 +44,11 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
         {
             ClearInternal(false);
 
-            OsuHitObject start = Entry.Start;
+            var entry = Entry;
-            OsuHitObject end = Entry.End;
+            if (entry?.End == null) return;
+
+            OsuHitObject start = entry.Start;
+            OsuHitObject end = entry.End;
 
             double startTime = start.GetEndTime();
 
@@ -87,14 +86,13 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
                     fp.FadeIn(end.TimeFadeIn);
                     fp.ScaleTo(end.Scale, end.TimeFadeIn, Easing.Out);
                     fp.MoveTo(pointEndPosition, end.TimeFadeIn, Easing.Out);
-                    fp.Delay(fadeOutTime - fadeInTime).FadeOut(end.TimeFadeIn);
+                    fp.Delay(fadeOutTime - fadeInTime).FadeOut(end.TimeFadeIn).Expire();
 
-                    finalTransformEndTime = fadeOutTime + end.TimeFadeIn;
+                    finalTransformEndTime = fp.LifetimeEnd;
                 }
             }
 
-            // todo: use Expire() on FollowPoints and take lifetime from them when https://github.com/ppy/osu-framework/issues/3300 is fixed.
+            entry.LifetimeEnd = finalTransformEndTime;
-            Entry.LifetimeEnd = finalTransformEndTime;
         }
 
         /// <summary>

osu.Game.Rulesets.Osu/Objects/Drawables/Connections/FollowPointLifetimeEntry.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;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics.Performance;
@@ -11,7 +13,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
 {
     public class FollowPointLifetimeEntry : LifetimeEntry
     {
-        public event Action Invalidated;
+        public event Action? Invalidated;
         public readonly OsuHitObject Start;
 
         public FollowPointLifetimeEntry(OsuHitObject start)
@@ -22,9 +24,9 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
             bindEvents();
         }
 
-        private OsuHitObject end;
+        private OsuHitObject? end;
 
-        public OsuHitObject End
+        public OsuHitObject? End
         {
             get => end;
             set
@@ -55,12 +57,9 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
         }
 
         public void UnbindEvents()
-        {
-            if (Start != null)
         {
             Start.DefaultsApplied -= onDefaultsApplied;
             Start.PositionBindable.ValueChanged -= onPositionChanged;
-            }
 
             if (End != null)
             {

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

@@ -6,43 +6,32 @@ using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Extensions;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
-using osu.Framework.Graphics.Performance;
 using osu.Framework.Graphics.Pooling;
 using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Pooling;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
 {
     /// <summary>
     /// Visualises connections between <see cref="DrawableOsuHitObject"/>s.
     /// </summary>
-    public class FollowPointRenderer : CompositeDrawable
+    public class FollowPointRenderer : PooledDrawableWithLifetimeContainer<FollowPointLifetimeEntry, FollowPointConnection>
     {
-        public override bool RemoveCompletedTransforms => false;
+        public new IReadOnlyList<FollowPointLifetimeEntry> Entries => lifetimeEntries;
-
-        public IReadOnlyList<FollowPointLifetimeEntry> Entries => lifetimeEntries;
 
         private DrawablePool<FollowPointConnection> connectionPool;
         private DrawablePool<FollowPoint> pointPool;
 
         private readonly List<FollowPointLifetimeEntry> lifetimeEntries = new List<FollowPointLifetimeEntry>();
-        private readonly Dictionary<LifetimeEntry, FollowPointConnection> connectionsInUse = new Dictionary<LifetimeEntry, FollowPointConnection>();
         private readonly Dictionary<HitObject, IBindable> startTimeMap = new Dictionary<HitObject, IBindable>();
-        private readonly LifetimeEntryManager lifetimeManager = new LifetimeEntryManager();
-
-        public FollowPointRenderer()
-        {
-            lifetimeManager.EntryBecameAlive += onEntryBecameAlive;
-            lifetimeManager.EntryBecameDead += onEntryBecameDead;
-        }
 
         [BackgroundDependencyLoader]
         private void load()
         {
             InternalChildren = new Drawable[]
             {
-                connectionPool = new DrawablePoolNoLifetime<FollowPointConnection>(1, 200),
+                connectionPool = new DrawablePool<FollowPointConnection>(1, 200),
-                pointPool = new DrawablePoolNoLifetime<FollowPoint>(50, 1000)
+                pointPool = new DrawablePool<FollowPoint>(50, 1000)
             };
         }
 
@@ -107,7 +96,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
                 previousEntry.End = newEntry.Start;
             }
 
-            lifetimeManager.AddEntry(newEntry);
+            Add(newEntry);
         }
 
         private void removeEntry(OsuHitObject hitObject)
@@ -118,7 +107,7 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
             entry.UnbindEvents();
 
             lifetimeEntries.RemoveAt(index);
-            lifetimeManager.RemoveEntry(entry);
+            Remove(entry);
 
             if (index > 0)
             {
@@ -131,30 +120,12 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
             }
         }
 
-        protected override bool CheckChildrenLife()
+        protected override FollowPointConnection GetDrawable(FollowPointLifetimeEntry entry)
         {
-            bool anyAliveChanged = base.CheckChildrenLife();
+            var connection = connectionPool.Get();
-            anyAliveChanged |= lifetimeManager.Update(Time.Current);
+            connection.Pool = pointPool;
-            return anyAliveChanged;
+            connection.Apply(entry);
-        }
+            return connection;
-
-        private void onEntryBecameAlive(LifetimeEntry entry)
-        {
-            var connection = connectionPool.Get(c =>
-            {
-                c.Entry = (FollowPointLifetimeEntry)entry;
-                c.Pool = pointPool;
-            });
-
-            connectionsInUse[entry] = connection;
-
-            AddInternal(connection);
-        }
-
-        private void onEntryBecameDead(LifetimeEntry entry)
-        {
-            RemoveInternal(connectionsInUse[entry]);
-            connectionsInUse.Remove(entry);
         }
 
         private void onStartTimeChanged(OsuHitObject hitObject)
@@ -171,16 +142,5 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables.Connections
                 entry.UnbindEvents();
             lifetimeEntries.Clear();
         }
-
-        private class DrawablePoolNoLifetime<T> : DrawablePool<T>
-            where T : PoolableDrawable, new()
-        {
-            public override bool RemoveWhenNotAlive => false;
-
-            public DrawablePoolNoLifetime(int initialSize, int? maximumSize = null)
-                : base(initialSize, maximumSize)
-            {
-            }
-        }
     }
 }

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

@@ -182,8 +182,6 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             // todo: temporary / arbitrary, used for lifetime optimisation.
             this.Delay(800).FadeOut();
 
-            (CirclePiece.Drawable as IMainCirclePiece)?.Animate(state);
-
             switch (state)
             {
                 case ArmedState.Idle:

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

@@ -97,8 +97,6 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         {
             base.UpdateHitStateTransforms(state);
 
-            (CirclePiece.Drawable as IMainCirclePiece)?.Animate(state);
-
             switch (state)
             {
                 case ArmedState.Idle:
@@ -154,7 +152,8 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
             while (Math.Abs(aimRotation - Arrow.Rotation) > 180)
                 aimRotation += aimRotation < Arrow.Rotation ? 360 : -360;
 
-            if (!hasRotation)
+            // The clock may be paused in a scenario like the editor.
+            if (!hasRotation || !Clock.IsRunning)
             {
                 Arrow.Rotation = aimRotation;
                 hasRotation = true;

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

@@ -7,13 +7,14 @@ using osu.Framework.Allocation;
 using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Osu.Skinning.Default;
 using osu.Game.Skinning;
 using osuTK;
 
 namespace osu.Game.Rulesets.Osu.Objects.Drawables
 {
-    public class DrawableSliderTail : DrawableOsuHitObject, IRequireTracking, ITrackSnaking, IHasMainCirclePiece
+    public class DrawableSliderTail : DrawableOsuHitObject, IRequireTracking, IHasMainCirclePiece
     {
         public new SliderTailCircle HitObject => (SliderTailCircle)base.HitObject;
 
@@ -86,8 +87,6 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
 
             Debug.Assert(HitObject.HitWindows != null);
 
-            (CirclePiece.Drawable as IMainCirclePiece)?.Animate(state);
-
             switch (state)
             {
                 case ArmedState.Idle:
@@ -111,7 +110,12 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
                 ApplyResult(r => r.Type = Tracking ? r.Judgement.MaxResult : r.Judgement.MinResult);
         }
 
-        public void UpdateSnakingPosition(Vector2 start, Vector2 end) =>
+        protected override void OnApply()
-            Position = HitObject.RepeatIndex % 2 == 0 ? end : start;
+        {
+            base.OnApply();
+
+            if (Slider != null)
+                Position = Slider.CurvePositionAt(HitObject.RepeatIndex % 2 == 0 ? 1 : 0);
+        }
     }
 }

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

@@ -18,9 +18,9 @@ namespace osu.Game.Rulesets.Osu.Objects.Drawables
         {
         }
 
-        protected override void SkinChanged(ISkinSource skin, bool allowFallback)
+        protected override void SkinChanged(ISkinSource skin)
         {
-            base.SkinChanged(skin, allowFallback);
+            base.SkinChanged(skin);
             updateColour();
         }
 

osu.Game.Rulesets.Osu/OsuRuleset.cs

@@ -164,7 +164,8 @@ namespace osu.Game.Rulesets.Osu
                     {
                         new OsuModTarget(),
                         new OsuModDifficultyAdjust(),
-                        new OsuModClassic()
+                        new OsuModClassic(),
+                        new OsuModRandom(),
                     };
 
                 case ModType.Automation:

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

@@ -42,6 +42,10 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
                     Origin = Anchor.Centre,
                     Texture = textures.Get(@"Gameplay/osu/disc"),
                 },
+                new KiaiFlash
+                {
+                    RelativeSizeAxes = Axes.Both,
+                },
                 triangles = new TrianglesPiece
                 {
                     RelativeSizeAxes = Axes.Both,

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

@@ -128,5 +128,13 @@ namespace osu.Game.Rulesets.Osu.Skinning.Default
                     spmContainer.FadeIn(drawableSpinner.HitObject.TimeFadeIn);
             }
         }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            if (drawableSpinner != null)
+                drawableSpinner.ApplyCustomUpdateState -= updateStateTransforms;
+        }
     }
 }

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

@@ -1,17 +0,0 @@
-// 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.Objects.Drawables;
-using osu.Game.Rulesets.Osu.Objects.Drawables;
-
-namespace osu.Game.Rulesets.Osu.Skinning.Default
-{
-    public interface IMainCirclePiece
-    {
-        /// <summary>
-        /// Begins animating this <see cref="IMainCirclePiece"/>.
-        /// </summary>
-        /// <param name="state">The <see cref="ArmedState"/> of the related <see cref="DrawableHitCircle"/>.</param>
-        void Animate(ArmedState state);
-    }
-}

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

@@ -0,0 +1,43 @@
+// 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.Audio.Track;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Shapes;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Graphics.Containers;
+using osuTK.Graphics;
+
+namespace osu.Game.Rulesets.Osu.Skinning.Default
+{
+    public class KiaiFlash : BeatSyncedContainer
+    {
+        private const double fade_length = 80;
+
+        private const float flash_opacity = 0.25f;
+
+        public KiaiFlash()
+        {
+            EarlyActivationMilliseconds = 80;
+            Blending = BlendingParameters.Additive;
+
+            Child = new Box
+            {
+                RelativeSizeAxes = Axes.Both,
+                Colour = Color4.White,
+                Alpha = 0f,
+            };
+        }
+
+        protected override void OnNewBeat(int beatIndex, TimingControlPoint timingPoint, EffectControlPoint effectPoint, ChannelAmplitudes amplitudes)
+        {
+            if (!effectPoint.KiaiMode)
+                return;
+
+            Child
+                .FadeTo(flash_opacity, EarlyActivationMilliseconds, Easing.OutQuint)
+                .Then()
+                .FadeOut(timingPoint.BeatLength - fade_length, Easing.OutSine);
+        }
+    }
+}