Merge branch 'master' into diffspike-balance

.config/dotnet-tools.json

@@ -2,12 +2,6 @@
   "version": 1,
   "isRoot": true,
   "tools": {
-    "cake.tool": {
-      "version": "0.35.0",
-      "commands": [
-        "dotnet-cake"
-      ]
-    },
     "dotnet-format": {
       "version": "3.1.37601",
       "commands": [
@@ -20,20 +14,20 @@
         "jb"
       ]
     },
-    "nvika": {
+    "smoogipoo.nvika": {
-      "version": "2.0.0",
+      "version": "1.0.1",
       "commands": [
         "nvika"
       ]
     },
     "codefilesanity": {
-      "version": "15.0.0",
+      "version": "0.0.36",
       "commands": [
         "CodeFileSanity"
       ]
     },
     "ppy.localisationanalyser.tools": {
-      "version": "2021.524.0",
+      "version": "2021.705.0",
       "commands": [
         "localisation"
       ]

.editorconfig

@@ -157,7 +157,7 @@ csharp_style_unused_value_assignment_preference = discard_variable:warning
 
 #Style - variable declaration
 csharp_style_inlined_variable_declaration = true:warning
-csharp_style_deconstructed_variable_declaration = true:warning
+csharp_style_deconstructed_variable_declaration = false:silent
 
 #Style - other C# 7.x features
 dotnet_style_prefer_inferred_tuple_names = true:warning
@@ -168,8 +168,8 @@ dotnet_style_prefer_is_null_check_over_reference_equality_method = true:silent
 #Style - C# 8 features
 csharp_prefer_static_local_function = true:warning
 csharp_prefer_simple_using_statement = true:silent
-csharp_style_prefer_index_operator = true:warning
+csharp_style_prefer_index_operator = false:silent
-csharp_style_prefer_range_operator = true:warning
+csharp_style_prefer_range_operator = false:silent
 csharp_style_prefer_switch_expression = false:none
 
 #Supressing roslyn built-in analyzers

.github/workflows/ci.yml

@@ -0,0 +1,94 @@
+on: [push, pull_request]
+name: Continuous Integration
+
+jobs:
+  test:
+    name: Test
+    runs-on: ${{matrix.os.fullname}}
+    env:
+      OSU_EXECUTION_MODE: ${{matrix.threadingMode}}
+    strategy:
+       fail-fast: false
+       matrix:
+          os:
+            - { prettyname: Windows, fullname: windows-latest }
+            - { prettyname: macOS, fullname: macos-latest }
+            - { prettyname: Linux, fullname: ubuntu-latest }
+          threadingMode: ['SingleThread', 'MultiThreaded']
+    timeout-minutes: 60
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      - name: Install .NET 5.0.x
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: "5.0.x"
+
+      # FIXME: libavformat is not included in Ubuntu. Let's fix that.
+      # https://github.com/ppy/osu-framework/issues/4349
+      # Remove this once https://github.com/actions/virtual-environments/issues/3306 has been resolved.
+      - name: Install libavformat-dev
+        if: ${{matrix.os.fullname == 'ubuntu-latest'}}
+        run: |
+         sudo apt-get update && \
+         sudo apt-get -y install libavformat-dev
+
+      - name: Compile
+        run: dotnet build -c Debug -warnaserror osu.Desktop.slnf
+
+      - name: Test
+        run: dotnet test $pwd/*.Tests/bin/Debug/*/*.Tests.dll --logger "trx;LogFileName=TestResults-${{matrix.os.prettyname}}-${{matrix.threadingMode}}.trx"
+        shell: pwsh
+
+      # Attempt to upload results even if test fails.
+      # https://docs.github.com/en/actions/reference/context-and-expression-syntax-for-github-actions#always
+      - name: Upload Test Results
+        uses: actions/upload-artifact@v2
+        if: ${{ always() }}
+        with:
+          name: osu-test-results-${{matrix.os.prettyname}}-${{matrix.threadingMode}}
+          path: ${{github.workspace}}/TestResults/TestResults-${{matrix.os.prettyname}}-${{matrix.threadingMode}}.trx
+
+  inspect-code:
+    name: Code Quality
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+
+      # FIXME: Tools won't run in .NET 5.0 unless you install 3.1.x LTS side by side.
+      # https://itnext.io/how-to-support-multiple-net-sdks-in-github-actions-workflows-b988daa884e
+      - name: Install .NET 3.1.x LTS
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: "3.1.x"
+
+      - name: Install .NET 5.0.x
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: "5.0.x"
+
+      - name: Restore Tools
+        run: dotnet tool restore
+
+      - name: Restore Packages
+        run: dotnet restore
+
+      - name: CodeFileSanity
+        run: |
+          # TODO: Add ignore filters and GitHub Workflow Command Reporting in CFS. That way we don't have to do this workaround.
+          # FIXME: Suppress warnings from templates project
+          dotnet codefilesanity | while read -r line; do
+            echo "::warning::$line"
+          done
+
+      # Temporarily disabled due to test failures, but it won't work anyway until the tool is upgraded.
+      # - name: .NET Format (Dry Run)
+      #   run: dotnet format --dry-run --check
+
+      - name: InspectCode
+        run: dotnet jb inspectcode $(pwd)/osu.Desktop.slnf --output=$(pwd)/inspectcodereport.xml --cachesDir=$(pwd)/inspectcode --verbosity=WARN
+
+      - name: NVika
+        run: dotnet nvika parsereport "${{github.workspace}}/inspectcodereport.xml" --treatwarningsaserrors

.github/workflows/report-nunit.yml

@@ -0,0 +1,32 @@
+# This is a workaround to allow PRs to report their coverage. This will run inside the base repository.
+# See:
+#   * https://github.com/dorny/test-reporter#recommended-setup-for-public-repositories
+#   * https://docs.github.com/en/actions/reference/authentication-in-a-workflow#permissions-for-the-github_token
+name: Annotate CI run with test results
+on:
+  workflow_run:
+    workflows: ["Continuous Integration"]
+    types:
+      - completed
+jobs:
+  annotate:
+    name: Annotate CI run with test results
+    runs-on: ubuntu-latest
+    if: ${{ github.event.workflow_run.conclusion != 'cancelled' }}
+    strategy:
+       fail-fast: false
+       matrix:
+          os:
+            - { prettyname: Windows }
+            - { prettyname: macOS }
+            - { prettyname: Linux }
+          threadingMode: ['SingleThread', 'MultiThreaded']
+    timeout-minutes: 5
+    steps:
+      - name: Annotate CI run with test results
+        uses: dorny/test-reporter@v1.4.2
+        with:
+          artifact: osu-test-results-${{matrix.os.prettyname}}-${{matrix.threadingMode}}
+          name: Test Results (${{matrix.os.prettyname}}, ${{matrix.threadingMode}})
+          path: "*.trx"
+          reporter: dotnet-trx

.gitignore

@@ -336,3 +336,6 @@ inspectcode
 /BenchmarkDotNet.Artifacts
 
 *.GeneratedMSBuildEditorConfig.editorconfig
+
+# Fody (pulled in by Realm) - schema file
+FodyWeavers.xsd

.idea/.idea.osu.Desktop/.idea/dataSources.xml

@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="DataSourceManagerImpl" format="xml" multifile-model="true">
-    <data-source source="LOCAL" name="osu-client-sqlite" uuid="1aa4b9be-cd8d-47ae-8186-30a13cd724a5">
-      <driver-ref>sqlite.xerial</driver-ref>
-      <synchronize>true</synchronize>
-      <jdbc-driver>org.sqlite.JDBC</jdbc-driver>
-      <jdbc-url>jdbc:sqlite:$USER_HOME$/.local/share/osu/client.db</jdbc-url>
-      <driver-properties>
-        <property name="enable_load_extension" value="true" />
-      </driver-properties>
-    </data-source>
-  </component>
-</project>

.vscode/launch.json

@@ -113,20 +113,6 @@
             "cwd": "${workspaceRoot}",
             "preLaunchTask": "Build benchmarks",
             "console": "internalConsole"
-        },
-        {
-            "name": "Cake: Debug Script",
-            "type": "coreclr",
-            "request": "launch",
-            "program": "${workspaceRoot}/build/tools/Cake.CoreCLR/0.30.0/Cake.dll",
-            "args": [
-                "${workspaceRoot}/build/build.cake",
-                "--debug",
-                "--verbosity=diagnostic"
-            ],
-            "cwd": "${workspaceRoot}/build",
-            "stopAtEntry": true,
-            "externalConsole": false
         }
     ]
 }

CodeAnalysis/BannedSymbols.txt

@@ -3,6 +3,7 @@ M:System.Object.Equals(System.Object)~System.Boolean;Don't use object.Equals. Us
 M:System.ValueType.Equals(System.Object)~System.Boolean;Don't use object.Equals(Fallbacks to ValueType). Use IEquatable<T> or EqualityComparer<T>.Default instead.
 M:System.Nullable`1.Equals(System.Object)~System.Boolean;Use == instead.
 T:System.IComparable;Don't use non-generic IComparable. Use generic version instead.
+T:SixLabors.ImageSharp.IDeepCloneable`1;Use osu.Game.Utils.IDeepCloneable<T> instead.
 M:osu.Framework.Graphics.Sprites.SpriteText.#ctor;Use OsuSpriteText.
 M:osu.Framework.Bindables.IBindableList`1.GetBoundCopy();Fails on iOS. Use manual ctor + BindTo instead. (see https://github.com/mono/mono/issues/19900)
 T:Microsoft.EntityFrameworkCore.Internal.EnumerableExtensions;Don't use internal extension methods.

FodyWeavers.xml

@@ -0,0 +1,3 @@
+<Weavers xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="FodyWeavers.xsd">
+  <Realm DisableAnalytics="true" />
+</Weavers>

InspectCode.ps1

@@ -1,27 +1,11 @@
-[CmdletBinding()]
-Param(
-    [string]$Target,
-    [string]$Configuration,
-    [ValidateSet("Quiet", "Minimal", "Normal", "Verbose", "Diagnostic")]
-    [string]$Verbosity,
-    [switch]$ShowDescription,
-    [Alias("WhatIf", "Noop")]
-    [switch]$DryRun,
-    [Parameter(Position = 0, Mandatory = $false, ValueFromRemainingArguments = $true)]
-    [string[]]$ScriptArgs
-)
-
-# Build Cake arguments
-$cakeArguments = "";
-if ($Target) { $cakeArguments += "-target=$Target" }
-if ($Configuration) { $cakeArguments += "-configuration=$Configuration" }
-if ($Verbosity) { $cakeArguments += "-verbosity=$Verbosity" }
-if ($ShowDescription) { $cakeArguments += "-showdescription" }
-if ($DryRun) { $cakeArguments += "-dryrun" }
-if ($Experimental) { $cakeArguments += "-experimental" }
-$cakeArguments += $ScriptArgs
-
 dotnet tool restore
-dotnet cake ./build/InspectCode.cake --bootstrap
+
-dotnet cake ./build/InspectCode.cake $cakeArguments
+# Temporarily disabled until the tool is upgraded to 5.0.
+  # The version specified in .config/dotnet-tools.json (3.1.37601) won't run on .NET hosts >=5.0.7.
+  # - cmd: dotnet format --dry-run --check
+
+dotnet CodeFileSanity
+dotnet jb inspectcode "osu.Desktop.slnf" --output="inspectcodereport.xml" --caches-home="inspectcode" --verbosity=WARN
+dotnet nvika parsereport "inspectcodereport.xml" --treatwarningsaserrors
+
 exit $LASTEXITCODE

InspectCode.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+dotnet tool restore
+dotnet CodeFileSanity
+dotnet jb inspectcode "osu.Desktop.slnf" --output="inspectcodereport.xml" --caches-home="inspectcode" --verbosity=WARN
+dotnet nvika parsereport "inspectcodereport.xml" --treatwarningsaserrors

README.md

@@ -11,7 +11,7 @@
 
 A free-to-win rhythm game. Rhythm is just a *click* away!
 
-The future of [osu!](https://osu.ppy.sh) and the beginning of an open era! Commonly known by the codename *osu!lazer*. Pew pew.
+The future of [osu!](https://osu.ppy.sh) and the beginning of an open era! Currently known by and released under the codename "*lazer*". As in sharper than cutting-edge.
 
 ## Status
 
@@ -23,7 +23,7 @@ We are accepting bug reports (please report with as much detail as possible and
 
 - Detailed release changelogs are available on the [official osu! site](https://osu.ppy.sh/home/changelog/lazer).
 - You can learn more about our approach to [project management](https://github.com/ppy/osu/wiki/Project-management).
-- Read peppy's [latest blog post](https://blog.ppy.sh/a-definitive-lazer-faq/) exploring where lazer is currently and the roadmap going forward.
+- Read peppy's [blog post](https://blog.ppy.sh/a-definitive-lazer-faq/) exploring where the project is currently and the roadmap going forward.
 
 ## Running osu!
 
@@ -43,7 +43,7 @@ If your platform is not listed above, there is still a chance you can manually b
 
 osu! is designed to have extensible modular gameplay modes, called "rulesets". Building one of these allows a developer to harness the power of osu! for their own game style. To get started working on a ruleset, we have some templates available [here](https://github.com/ppy/osu/tree/master/Templates).
 
-You can see some examples of custom rulesets by visiting the [custom ruleset directory](https://github.com/ppy/osu/issues/5852).
+You can see some examples of custom rulesets by visiting the [custom ruleset directory](https://github.com/ppy/osu/discussions/13096).
 
 ## Developing osu!
 

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

@@ -12,7 +12,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <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 Include="NUnit3TestAdapter" Version="4.0.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>
   <ItemGroup>

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

@@ -12,7 +12,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <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 Include="NUnit3TestAdapter" Version="4.0.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>
   <ItemGroup>

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

@@ -12,7 +12,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <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 Include="NUnit3TestAdapter" Version="4.0.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>
   <ItemGroup>

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

@@ -12,7 +12,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <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 Include="NUnit3TestAdapter" Version="4.0.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>
   <ItemGroup>

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];
     }
 }

appveyor.yml

@@ -1,24 +1,27 @@
 clone_depth: 1
 version: '{branch}-{build}'
 image: Visual Studio 2019
+cache:
+  - '%LOCALAPPDATA%\NuGet\v3-cache -> appveyor.yml'
+
 dotnet_csproj:
   patch: true
   file: 'osu.Game\osu.Game.csproj' # Use wildcard when it's able to exclude Xamarin projects
   version: '0.0.{build}'
-cache:
+
-  - '%LOCALAPPDATA%\NuGet\v3-cache -> appveyor.yml'
 before_build:
-  - ps: dotnet --info # Useful when version mismatch between CI and local
+  - cmd: dotnet --info # Useful when version mismatch between CI and local
-  - ps: nuget restore -verbosity quiet # Only nuget.exe knows both new (.NET Core) and old (Xamarin) projects
+  - cmd: nuget restore -verbosity quiet # Only nuget.exe knows both new (.NET Core) and old (Xamarin) projects
+
 build:
   project: osu.sln
   parallel: true
   verbosity: minimal
   publish_nuget: true
+
 after_build:
-  - ps: dotnet tool restore
-  - ps: dotnet format --dry-run --check
   - ps: .\InspectCode.ps1
+
 test:
   assemblies:
     except:

build/Desktop.proj

@@ -1,17 +0,0 @@
-<Project Sdk="Microsoft.Build.Traversal">
-  <ItemGroup>
-    <ProjectReference Include="..\osu.Desktop\osu.Desktop.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Catch.Tests\osu.Game.Rulesets.Catch.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Catch\osu.Game.Rulesets.Catch.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Mania.Tests\osu.Game.Rulesets.Mania.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Mania\osu.Game.Rulesets.Mania.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Osu.Tests\osu.Game.Rulesets.Osu.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Osu\osu.Game.Rulesets.Osu.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Taiko.Tests\osu.Game.Rulesets.Taiko.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Rulesets.Taiko\osu.Game.Rulesets.Taiko.csproj" />
-    <ProjectReference Include="..\osu.Game.Tests\osu.Game.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Tournament.Tests\osu.Game.Tournament.Tests.csproj" />
-    <ProjectReference Include="..\osu.Game.Tournament\osu.Game.Tournament.csproj" />
-    <ProjectReference Include="..\osu.Game\osu.Game.csproj" />
-  </ItemGroup>
-</Project>

build/InspectCode.cake

@@ -1,41 +0,0 @@
-#addin "nuget:?package=CodeFileSanity&version=0.0.36"
-
-///////////////////////////////////////////////////////////////////////////////
-// ARGUMENTS
-///////////////////////////////////////////////////////////////////////////////
-
-var target = Argument("target", "CodeAnalysis");
-var configuration = Argument("configuration", "Release");
-
-var rootDirectory = new DirectoryPath("..");
-var sln = rootDirectory.CombineWithFilePath("osu.sln");
-var desktopSlnf = rootDirectory.CombineWithFilePath("osu.Desktop.slnf");
-
-///////////////////////////////////////////////////////////////////////////////
-// TASKS
-///////////////////////////////////////////////////////////////////////////////
-
-Task("InspectCode")
-    .Does(() => {
-        var inspectcodereport = "inspectcodereport.xml";
-        var cacheDir = "inspectcode";
-        var verbosity = AppVeyor.IsRunningOnAppVeyor ? "WARN" : "INFO"; // Don't flood CI output
-
-        DotNetCoreTool(rootDirectory.FullPath,
-            "jb", $@"inspectcode ""{desktopSlnf}"" --output=""{inspectcodereport}"" --caches-home=""{cacheDir}"" --verbosity={verbosity}");
-        DotNetCoreTool(rootDirectory.FullPath, "nvika", $@"parsereport ""{inspectcodereport}"" --treatwarningsaserrors");
-    });
-
-Task("CodeFileSanity")
-    .Does(() => {
-        ValidateCodeSanity(new ValidateCodeSanitySettings {
-            RootDirectory = rootDirectory.FullPath,
-            IsAppveyorBuild = AppVeyor.IsRunningOnAppVeyor
-        });
-    });
-
-Task("CodeAnalysis")
-    .IsDependentOn("CodeFileSanity")
-    .IsDependentOn("InspectCode");
-
-RunTarget(target);

cake.config

@@ -1,5 +0,0 @@
-
-[Nuget]
-Source=https://api.nuget.org/v3/index.json
-UseInProcessClient=true
-LoadDependencies=true

osu.Android.props

@@ -51,7 +51,11 @@
     <Reference Include="Java.Interop" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.525.0" />
+    <PackageReference Include="ppy.osu.Game.Resources" Version="2021.706.0" />
-    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.601.0" />
+    <PackageReference Include="ppy.osu.Framework.Android" Version="2021.714.0" />
+  </ItemGroup>
+  <ItemGroup Label="Transitive Dependencies">
+    <!-- Realm needs to be directly referenced in all Xamarin projects, as it will not pull in its transitive dependencies otherwise. -->
+    <PackageReference Include="Realm" Version="10.3.0" />
   </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/Updater/SquirrelUpdateManager.cs

@@ -68,6 +68,8 @@ namespace osu.Desktop.Updater
                     return false;
                 }
 
+                scheduleRecheck = false;
+
                 if (notification == null)
                 {
                     notification = new UpdateProgressNotification(this) { State = ProgressNotificationState.Active };
@@ -98,7 +100,6 @@ namespace osu.Desktop.Updater
                         // could fail if deltas are unavailable for full update path (https://github.com/Squirrel/Squirrel.Windows/issues/959)
                         // try again without deltas.
                         await checkForUpdateAsync(false, notification).ConfigureAwait(false);
-                        scheduleRecheck = false;
                     }
                     else
                     {
@@ -110,13 +111,14 @@ namespace osu.Desktop.Updater
             catch (Exception)
             {
                 // we'll ignore this and retry later. can be triggered by no internet connection or thread abortion.
+                scheduleRecheck = true;
             }
             finally
             {
                 if (scheduleRecheck)
                 {
                     // check again in 30 minutes.
-                    Scheduler.AddDelayed(async () => await checkForUpdateAsync().ConfigureAwait(false), 60000 * 30);
+                    Scheduler.AddDelayed(() => Task.Run(async () => await checkForUpdateAsync().ConfigureAwait(false)), 60000 * 30);
                 }
             }
 
@@ -141,7 +143,7 @@ namespace osu.Desktop.Updater
                 Activated = () =>
                 {
                     updateManager.PrepareUpdateAsync()
-                                 .ContinueWith(_ => updateManager.Schedule(() => game.GracefullyExit()));
+                                 .ContinueWith(_ => updateManager.Schedule(() => game?.GracefullyExit()));
                     return true;
                 };
             }

osu.Desktop/osu.Desktop.csproj

@@ -5,8 +5,8 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <Description>A free-to-win rhythm game. Rhythm is just a *click* away!</Description>
     <AssemblyName>osu!</AssemblyName>
-    <Title>osu!lazer</Title>
+    <Title>osu!</Title>
-    <Product>osu!lazer</Product>
+    <Product>osu!(lazer)</Product>
     <ApplicationIcon>lazer.ico</ApplicationIcon>
     <ApplicationManifest>app.manifest</ApplicationManifest>
     <Version>0.0.0</Version>

osu.Desktop/osu.nuspec

@@ -3,7 +3,7 @@
     <metadata>
         <id>osulazer</id>
         <version>0.0.0</version>
-        <title>osu!lazer</title>
+        <title>osu!</title>
         <authors>ppy Pty Ltd</authors>
         <owners>Dean Herbert</owners>
         <projectUrl>https://osu.ppy.sh/</projectUrl>
@@ -20,4 +20,3 @@
       <file src="**.config" target="lib\net45\"/>
     </files>
 </package>
-

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

@@ -9,7 +9,7 @@
   <ItemGroup>
     <PackageReference Include="BenchmarkDotNet" Version="0.13.0" />
     <PackageReference Include="nunit" Version="3.13.2" />
-    <PackageReference Include="NUnit3TestAdapter" Version="3.17.0" />
+    <PackageReference Include="NUnit3TestAdapter" Version="4.0.0" />
   </ItemGroup>
 
   <ItemGroup>

osu.Game.Rulesets.Catch.Tests/Editor/CatchEditorTestSceneContainer.cs

@@ -0,0 +1,66 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Timing;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Catch.Edit;
+using osu.Game.Rulesets.Catch.UI;
+using osu.Game.Rulesets.UI;
+using osu.Game.Rulesets.UI.Scrolling;
+using osu.Game.Tests.Visual;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public class CatchEditorTestSceneContainer : Container
+    {
+        [Cached(typeof(Playfield))]
+        public readonly ScrollingPlayfield Playfield;
+
+        protected override Container<Drawable> Content { get; }
+
+        public CatchEditorTestSceneContainer()
+        {
+            Anchor = Anchor.Centre;
+            Origin = Anchor.Centre;
+            Width = CatchPlayfield.WIDTH;
+            Height = 1000;
+            Padding = new MarginPadding
+            {
+                Bottom = 100
+            };
+
+            InternalChildren = new Drawable[]
+            {
+                new ScrollingTestContainer(ScrollingDirection.Down)
+                {
+                    TimeRange = 1000,
+                    RelativeSizeAxes = Axes.Both,
+                    Child = Playfield = new TestCatchPlayfield
+                    {
+                        RelativeSizeAxes = Axes.Both
+                    }
+                },
+                new PlayfieldBorder
+                {
+                    PlayfieldBorderStyle = { Value = PlayfieldBorderStyle.Full },
+                    Clock = new FramedClock(new StopwatchClock(true))
+                },
+                Content = new Container
+                {
+                    RelativeSizeAxes = Axes.Both
+                }
+            };
+        }
+
+        private class TestCatchPlayfield : CatchEditorPlayfield
+        {
+            public TestCatchPlayfield()
+                : base(new BeatmapDifficulty { CircleSize = 0 })
+            {
+            }
+        }
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/CatchPlacementBlueprintTestScene.cs

@@ -0,0 +1,79 @@
+// 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 NUnit.Framework;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Testing;
+using osu.Framework.Timing;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Objects.Drawables;
+using osu.Game.Rulesets.UI.Scrolling;
+using osu.Game.Tests.Visual;
+using osuTK;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public abstract class CatchPlacementBlueprintTestScene : PlacementBlueprintTestScene
+    {
+        protected const double TIME_SNAP = 100;
+
+        protected DrawableCatchHitObject LastObject;
+
+        protected new ScrollingHitObjectContainer HitObjectContainer => contentContainer.Playfield.HitObjectContainer;
+
+        protected override Container<Drawable> Content => contentContainer;
+
+        private readonly CatchEditorTestSceneContainer contentContainer;
+
+        protected CatchPlacementBlueprintTestScene()
+        {
+            base.Content.Add(contentContainer = new CatchEditorTestSceneContainer());
+
+            contentContainer.Playfield.Clock = new FramedClock(new ManualClock());
+        }
+
+        [SetUp]
+        public void Setup() => Schedule(() =>
+        {
+            HitObjectContainer.Clear();
+            ResetPlacement();
+            LastObject = null;
+        });
+
+        protected void AddMoveStep(double time, float x) => AddStep($"move to time={time}, x={x}", () =>
+        {
+            float y = HitObjectContainer.PositionAtTime(time);
+            Vector2 pos = HitObjectContainer.ToScreenSpace(new Vector2(x, y + HitObjectContainer.DrawHeight));
+            InputManager.MoveMouseTo(pos);
+        });
+
+        protected void AddClickStep(MouseButton button) => AddStep($"click {button}", () =>
+        {
+            InputManager.Click(button);
+        });
+
+        protected IEnumerable<FruitOutline> FruitOutlines => Content.ChildrenOfType<FruitOutline>();
+
+        // Unused because AddHitObject is overriden
+        protected override Container CreateHitObjectContainer() => new Container();
+
+        protected override void AddHitObject(DrawableHitObject hitObject)
+        {
+            LastObject = (DrawableCatchHitObject)hitObject;
+            contentContainer.Playfield.HitObjectContainer.Add(hitObject);
+        }
+
+        protected override SnapResult SnapForBlueprint(PlacementBlueprint blueprint)
+        {
+            var result = base.SnapForBlueprint(blueprint);
+            result.Time = Math.Round(HitObjectContainer.TimeAtScreenSpacePosition(result.ScreenSpacePosition) / TIME_SNAP) * TIME_SNAP;
+            return result;
+        }
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/CatchSelectionBlueprintTestScene.cs

@@ -0,0 +1,24 @@
+// 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;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Rulesets.UI.Scrolling;
+using osu.Game.Tests.Visual;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public abstract class CatchSelectionBlueprintTestScene : SelectionBlueprintTestScene
+    {
+        protected ScrollingHitObjectContainer HitObjectContainer => contentContainer.Playfield.HitObjectContainer;
+
+        protected override Container<Drawable> Content => contentContainer;
+
+        private readonly CatchEditorTestSceneContainer contentContainer;
+
+        protected CatchSelectionBlueprintTestScene()
+        {
+            base.Content.Add(contentContainer = new CatchEditorTestSceneContainer());
+        }
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/TestSceneBananaShowerPlacementBlueprint.cs

@@ -0,0 +1,87 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Testing;
+using osu.Framework.Utils;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Rulesets.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Drawables;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public class TestSceneBananaShowerPlacementBlueprint : CatchPlacementBlueprintTestScene
+    {
+        protected override DrawableHitObject CreateHitObject(HitObject hitObject) => new DrawableBananaShower((BananaShower)hitObject);
+
+        protected override PlacementBlueprint CreateBlueprint() => new BananaShowerPlacementBlueprint();
+
+        protected override void AddHitObject(DrawableHitObject hitObject)
+        {
+            // Create nested bananas (but positions are not randomized because beatmap processing is not done).
+            hitObject.HitObject.ApplyDefaults(new ControlPointInfo(), Beatmap.Value.BeatmapInfo.BaseDifficulty);
+
+            base.AddHitObject(hitObject);
+        }
+
+        [Test]
+        public void TestBasicPlacement()
+        {
+            const double start_time = 100;
+            const double end_time = 500;
+
+            AddMoveStep(start_time, 0);
+            AddClickStep(MouseButton.Left);
+            AddMoveStep(end_time, 0);
+            AddClickStep(MouseButton.Right);
+            AddAssert("banana shower is placed", () => LastObject is DrawableBananaShower);
+            AddAssert("start time is correct", () => Precision.AlmostEquals(LastObject.HitObject.StartTime, start_time));
+            AddAssert("end time is correct", () => Precision.AlmostEquals(LastObject.HitObject.GetEndTime(), end_time));
+        }
+
+        [Test]
+        public void TestReversePlacement()
+        {
+            const double start_time = 100;
+            const double end_time = 500;
+
+            AddMoveStep(end_time, 0);
+            AddClickStep(MouseButton.Left);
+            AddMoveStep(start_time, 0);
+            AddClickStep(MouseButton.Right);
+            AddAssert("start time is correct", () => Precision.AlmostEquals(LastObject.HitObject.StartTime, start_time));
+            AddAssert("end time is correct", () => Precision.AlmostEquals(LastObject.HitObject.GetEndTime(), end_time));
+        }
+
+        [Test]
+        public void TestFinishWithZeroDuration()
+        {
+            AddMoveStep(100, 0);
+            AddClickStep(MouseButton.Left);
+            AddClickStep(MouseButton.Right);
+            AddAssert("banana shower is not placed", () => LastObject == null);
+            AddAssert("state is waiting", () => CurrentBlueprint?.PlacementActive == PlacementBlueprint.PlacementState.Waiting);
+        }
+
+        [Test]
+        public void TestOpacity()
+        {
+            AddMoveStep(100, 0);
+            AddClickStep(MouseButton.Left);
+            AddUntilStep("outline is semitransparent", () => Precision.DefinitelyBigger(1, timeSpanOutline.Alpha));
+            AddMoveStep(200, 0);
+            AddUntilStep("outline is opaque", () => Precision.AlmostEquals(timeSpanOutline.Alpha, 1));
+            AddMoveStep(100, 0);
+            AddUntilStep("outline is semitransparent", () => Precision.DefinitelyBigger(1, timeSpanOutline.Alpha));
+        }
+
+        private TimeSpanOutline timeSpanOutline => Content.ChildrenOfType<TimeSpanOutline>().Single();
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/TestSceneEditor.cs

@@ -0,0 +1,14 @@
+// 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.Tests.Visual;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    [TestFixture]
+    public class TestSceneEditor : EditorTestScene
+    {
+        protected override Ruleset CreateEditorRuleset() => new CatchRuleset();
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/TestSceneFruitPlacementBlueprint.cs

@@ -0,0 +1,44 @@
+// 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.Utils;
+using osu.Game.Rulesets.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Catch.UI;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Drawables;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public class TestSceneFruitPlacementBlueprint : CatchPlacementBlueprintTestScene
+    {
+        protected override DrawableHitObject CreateHitObject(HitObject hitObject) => new DrawableFruit((Fruit)hitObject);
+
+        protected override PlacementBlueprint CreateBlueprint() => new FruitPlacementBlueprint();
+
+        [Test]
+        public void TestFruitPlacementPosition()
+        {
+            const double time = 300;
+            const float x = CatchPlayfield.CENTER_X;
+
+            AddMoveStep(time, x);
+            AddClickStep(MouseButton.Left);
+
+            AddAssert("outline position is correct", () =>
+            {
+                var outline = FruitOutlines.Single();
+                return Precision.AlmostEquals(outline.X, x) &&
+                       Precision.AlmostEquals(outline.Y, HitObjectContainer.PositionAtTime(time));
+            });
+
+            AddAssert("fruit time is correct", () => Precision.AlmostEquals(LastObject.StartTimeBindable.Value, time));
+            AddAssert("fruit position is correct", () => Precision.AlmostEquals(LastObject.X, x));
+        }
+    }
+}

osu.Game.Rulesets.Catch.Tests/Editor/TestSceneJuiceStreamSelectionBlueprint.cs

@@ -0,0 +1,38 @@
+// 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.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Rulesets.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Tests.Editor
+{
+    public class TestSceneJuiceStreamSelectionBlueprint : CatchSelectionBlueprintTestScene
+    {
+        public TestSceneJuiceStreamSelectionBlueprint()
+        {
+            var hitObject = new JuiceStream
+            {
+                OriginalX = 100,
+                StartTime = 100,
+                Path = new SliderPath(PathType.PerfectCurve, new[]
+                {
+                    Vector2.Zero,
+                    new Vector2(200, 100),
+                    new Vector2(0, 200),
+                }),
+            };
+            var controlPoint = new ControlPointInfo();
+            controlPoint.Add(0, new TimingControlPoint
+            {
+                BeatLength = 100
+            });
+            hitObject.ApplyDefaults(controlPoint, new BeatmapDifficulty { CircleSize = 0 });
+            AddBlueprint(new JuiceStreamSelectionBlueprint(hitObject));
+        }
+    }
+}

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

@@ -0,0 +1,288 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using NUnit.Framework;
+using osu.Framework.Utils;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Tests
+{
+    [TestFixture]
+    public class JuiceStreamPathTest
+    {
+        [TestCase(1e3, true, false)]
+        // When the coordinates are large, the slope invariant fails within the specified absolute allowance due to the floating-number precision.
+        [TestCase(1e9, false, false)]
+        // Using discrete values sometimes discover more edge cases.
+        [TestCase(10, true, true)]
+        public void TestRandomInsertSetPosition(double scale, bool checkSlope, bool integralValues)
+        {
+            var rng = new Random(1);
+            var path = new JuiceStreamPath();
+
+            for (int iteration = 0; iteration < 100000; iteration++)
+            {
+                if (rng.Next(10) == 0)
+                    path.Clear();
+
+                int vertexCount = path.Vertices.Count;
+
+                switch (rng.Next(2))
+                {
+                    case 0:
+                    {
+                        double distance = rng.NextDouble() * scale * 2 - scale;
+                        if (integralValues)
+                            distance = Math.Round(distance);
+
+                        float oldX = path.PositionAtDistance(distance);
+                        int index = path.InsertVertex(distance);
+                        Assert.That(path.Vertices.Count, Is.EqualTo(vertexCount + 1));
+                        Assert.That(path.Vertices[index].Distance, Is.EqualTo(distance));
+                        Assert.That(path.Vertices[index].X, Is.EqualTo(oldX));
+                        break;
+                    }
+
+                    case 1:
+                    {
+                        int index = rng.Next(path.Vertices.Count);
+                        double distance = path.Vertices[index].Distance;
+                        float newX = (float)(rng.NextDouble() * scale * 2 - scale);
+                        if (integralValues)
+                            newX = MathF.Round(newX);
+
+                        path.SetVertexPosition(index, newX);
+                        Assert.That(path.Vertices.Count, Is.EqualTo(vertexCount));
+                        Assert.That(path.Vertices[index].Distance, Is.EqualTo(distance));
+                        Assert.That(path.Vertices[index].X, Is.EqualTo(newX));
+                        break;
+                    }
+                }
+
+                assertInvariants(path.Vertices, checkSlope);
+            }
+        }
+
+        [Test]
+        public void TestRemoveVertices()
+        {
+            var path = new JuiceStreamPath();
+            path.Add(10, 5);
+            path.Add(20, -5);
+
+            int removeCount = path.RemoveVertices((v, i) => v.Distance == 10 && i == 1);
+            Assert.That(removeCount, Is.EqualTo(1));
+            Assert.That(path.Vertices, Is.EqualTo(new[]
+            {
+                new JuiceStreamPathVertex(0, 0),
+                new JuiceStreamPathVertex(20, -5)
+            }));
+
+            removeCount = path.RemoveVertices((_, i) => i == 0);
+            Assert.That(removeCount, Is.EqualTo(1));
+            Assert.That(path.Vertices, Is.EqualTo(new[]
+            {
+                new JuiceStreamPathVertex(20, -5)
+            }));
+
+            removeCount = path.RemoveVertices((_, i) => true);
+            Assert.That(removeCount, Is.EqualTo(1));
+            Assert.That(path.Vertices, Is.EqualTo(new[]
+            {
+                new JuiceStreamPathVertex()
+            }));
+        }
+
+        [Test]
+        public void TestResampleVertices()
+        {
+            var path = new JuiceStreamPath();
+            path.Add(-100, -10);
+            path.Add(100, 50);
+            path.ResampleVertices(new double[]
+            {
+                -50,
+                0,
+                70,
+                120
+            });
+            Assert.That(path.Vertices, Is.EqualTo(new[]
+            {
+                new JuiceStreamPathVertex(-100, -10),
+                new JuiceStreamPathVertex(-50, -5),
+                new JuiceStreamPathVertex(0, 0),
+                new JuiceStreamPathVertex(70, 35),
+                new JuiceStreamPathVertex(100, 50),
+                new JuiceStreamPathVertex(100, 50),
+            }));
+
+            path.Clear();
+            path.SetVertexPosition(0, 10);
+            path.ResampleVertices(Array.Empty<double>());
+            Assert.That(path.Vertices, Is.EqualTo(new[]
+            {
+                new JuiceStreamPathVertex(0, 10)
+            }));
+        }
+
+        [Test]
+        public void TestRandomConvertFromSliderPath()
+        {
+            var rng = new Random(1);
+            var path = new JuiceStreamPath();
+            var sliderPath = new SliderPath();
+
+            for (int iteration = 0; iteration < 10000; iteration++)
+            {
+                sliderPath.ControlPoints.Clear();
+
+                do
+                {
+                    int start = sliderPath.ControlPoints.Count;
+
+                    do
+                    {
+                        float x = (float)(rng.NextDouble() * 1e3);
+                        float y = (float)(rng.NextDouble() * 1e3);
+                        sliderPath.ControlPoints.Add(new PathControlPoint(new Vector2(x, y)));
+                    } while (rng.Next(2) != 0);
+
+                    int length = sliderPath.ControlPoints.Count - start + 1;
+                    sliderPath.ControlPoints[start].Type.Value = length <= 2 ? PathType.Linear : length == 3 ? PathType.PerfectCurve : PathType.Bezier;
+                } while (rng.Next(3) != 0);
+
+                if (rng.Next(5) == 0)
+                    sliderPath.ExpectedDistance.Value = rng.NextDouble() * 3e3;
+                else
+                    sliderPath.ExpectedDistance.Value = null;
+
+                path.ConvertFromSliderPath(sliderPath);
+                Assert.That(path.Vertices[0].Distance, Is.EqualTo(0));
+                Assert.That(path.Distance, Is.EqualTo(sliderPath.Distance).Within(1e-3));
+                assertInvariants(path.Vertices, true);
+
+                double[] sampleDistances = Enumerable.Range(0, 10)
+                                                     .Select(_ => rng.NextDouble() * sliderPath.Distance)
+                                                     .ToArray();
+
+                foreach (double distance in sampleDistances)
+                {
+                    float expected = sliderPath.PositionAt(distance / sliderPath.Distance).X;
+                    Assert.That(path.PositionAtDistance(distance), Is.EqualTo(expected).Within(1e-3));
+                }
+
+                path.ResampleVertices(sampleDistances);
+                assertInvariants(path.Vertices, true);
+
+                foreach (double distance in sampleDistances)
+                {
+                    float expected = sliderPath.PositionAt(distance / sliderPath.Distance).X;
+                    Assert.That(path.PositionAtDistance(distance), Is.EqualTo(expected).Within(1e-3));
+                }
+            }
+        }
+
+        [Test]
+        public void TestRandomConvertToSliderPath()
+        {
+            var rng = new Random(1);
+            var path = new JuiceStreamPath();
+            var sliderPath = new SliderPath();
+
+            for (int iteration = 0; iteration < 10000; iteration++)
+            {
+                path.Clear();
+
+                do
+                {
+                    double distance = rng.NextDouble() * 1e3;
+                    float x = (float)(rng.NextDouble() * 1e3);
+                    path.Add(distance, x);
+                } while (rng.Next(5) != 0);
+
+                float sliderStartY = (float)(rng.NextDouble() * JuiceStreamPath.OSU_PLAYFIELD_HEIGHT);
+
+                path.ConvertToSliderPath(sliderPath, sliderStartY);
+                Assert.That(sliderPath.Distance, Is.EqualTo(path.Distance).Within(1e-3));
+                Assert.That(sliderPath.ControlPoints[0].Position.Value.X, Is.EqualTo(path.Vertices[0].X));
+                assertInvariants(path.Vertices, true);
+
+                foreach (var point in sliderPath.ControlPoints)
+                {
+                    Assert.That(point.Type.Value, Is.EqualTo(PathType.Linear).Or.Null);
+                    Assert.That(sliderStartY + point.Position.Value.Y, Is.InRange(0, JuiceStreamPath.OSU_PLAYFIELD_HEIGHT));
+                }
+
+                for (int i = 0; i < 10; i++)
+                {
+                    double distance = rng.NextDouble() * path.Distance;
+                    float expected = path.PositionAtDistance(distance);
+                    Assert.That(sliderPath.PositionAt(distance / sliderPath.Distance).X, Is.EqualTo(expected).Within(1e-3));
+                }
+            }
+        }
+
+        [Test]
+        public void TestInvalidation()
+        {
+            var path = new JuiceStreamPath();
+            Assert.That(path.InvalidationID, Is.EqualTo(1));
+            int previousId = path.InvalidationID;
+
+            path.InsertVertex(10);
+            checkNewId();
+
+            path.SetVertexPosition(1, 5);
+            checkNewId();
+
+            path.Add(20, 0);
+            checkNewId();
+
+            path.RemoveVertices((v, _) => v.Distance == 20);
+            checkNewId();
+
+            path.ResampleVertices(new double[] { 5, 10, 15 });
+            checkNewId();
+
+            path.Clear();
+            checkNewId();
+
+            path.ConvertFromSliderPath(new SliderPath());
+            checkNewId();
+
+            void checkNewId()
+            {
+                Assert.That(path.InvalidationID, Is.Not.EqualTo(previousId));
+                previousId = path.InvalidationID;
+            }
+        }
+
+        private void assertInvariants(IReadOnlyList<JuiceStreamPathVertex> vertices, bool checkSlope)
+        {
+            Assert.That(vertices, Is.Not.Empty);
+
+            for (int i = 0; i < vertices.Count; i++)
+            {
+                Assert.That(double.IsFinite(vertices[i].Distance));
+                Assert.That(float.IsFinite(vertices[i].X));
+            }
+
+            for (int i = 1; i < vertices.Count; i++)
+            {
+                Assert.That(vertices[i].Distance, Is.GreaterThanOrEqualTo(vertices[i - 1].Distance));
+
+                if (!checkSlope) continue;
+
+                float xDiff = Math.Abs(vertices[i].X - vertices[i - 1].X);
+                double distanceDiff = vertices[i].Distance - vertices[i - 1].Distance;
+                Assert.That(xDiff, Is.LessThanOrEqualTo(distanceDiff).Within(Precision.FLOAT_EPSILON));
+            }
+        }
+    }
+}

osu.Game.Rulesets.Catch.Tests/Resources/old-skin/skin.ini

@@ -0,0 +1,2 @@
+[General]
+// no version specified means v1

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/TestSceneCatchSkinConfiguration.cs

@@ -0,0 +1,114 @@
+// 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.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Testing;
+using osu.Framework.Utils;
+using osu.Game.Beatmaps;
+using osu.Game.Beatmaps.ControlPoints;
+using osu.Game.Rulesets.Catch.Judgements;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Catch.Objects.Drawables;
+using osu.Game.Rulesets.Catch.Skinning;
+using osu.Game.Rulesets.Catch.UI;
+using osu.Game.Skinning;
+using osu.Game.Tests.Visual;
+using Direction = osu.Game.Rulesets.Catch.UI.Direction;
+
+namespace osu.Game.Rulesets.Catch.Tests
+{
+    public class TestSceneCatchSkinConfiguration : OsuTestScene
+    {
+        [Cached]
+        private readonly DroppedObjectContainer droppedObjectContainer;
+
+        private Catcher catcher;
+
+        private readonly Container container;
+
+        public TestSceneCatchSkinConfiguration()
+        {
+            Add(droppedObjectContainer = new DroppedObjectContainer());
+            Add(container = new Container { RelativeSizeAxes = Axes.Both });
+        }
+
+        [TestCase(false)]
+        [TestCase(true)]
+        public void TestCatcherPlateFlipping(bool flip)
+        {
+            AddStep("setup catcher", () =>
+            {
+                var skin = new TestSkin { FlipCatcherPlate = flip };
+                container.Child = new SkinProvidingContainer(skin)
+                {
+                    Child = catcher = new Catcher(new Container())
+                    {
+                        Anchor = Anchor.Centre
+                    }
+                };
+            });
+
+            Fruit fruit = new Fruit();
+
+            AddStep("catch fruit", () => catchFruit(fruit, 20));
+
+            float position = 0;
+
+            AddStep("record fruit position", () => position = getCaughtObjectPosition(fruit));
+
+            AddStep("face left", () => catcher.VisualDirection = Direction.Left);
+
+            if (flip)
+                AddAssert("fruit position changed", () => !Precision.AlmostEquals(getCaughtObjectPosition(fruit), position));
+            else
+                AddAssert("fruit position unchanged", () => Precision.AlmostEquals(getCaughtObjectPosition(fruit), position));
+
+            AddStep("face right", () => catcher.VisualDirection = Direction.Right);
+
+            AddAssert("fruit position restored", () => Precision.AlmostEquals(getCaughtObjectPosition(fruit), position));
+        }
+
+        private float getCaughtObjectPosition(Fruit fruit)
+        {
+            var caughtObject = catcher.ChildrenOfType<CaughtObject>().Single(c => c.HitObject == fruit);
+            return caughtObject.Parent.ToSpaceOfOtherDrawable(caughtObject.Position, catcher).X;
+        }
+
+        private void catchFruit(Fruit fruit, float x)
+        {
+            fruit.ApplyDefaults(new ControlPointInfo(), new BeatmapDifficulty());
+            var drawableFruit = new DrawableFruit(fruit) { X = x };
+            var judgement = fruit.CreateJudgement();
+            catcher.OnNewResult(drawableFruit, new CatchJudgementResult(fruit, judgement)
+            {
+                Type = judgement.MaxResult
+            });
+        }
+
+        private class TestSkin : DefaultSkin
+        {
+            public bool FlipCatcherPlate { get; set; }
+
+            public TestSkin()
+                : base(null)
+            {
+            }
+
+            public override IBindable<TValue> GetConfig<TLookup, TValue>(TLookup lookup)
+            {
+                if (lookup is CatchSkinConfiguration config)
+                {
+                    if (config == CatchSkinConfiguration.FlipCatcherPlate)
+                        return SkinUtils.As<TValue>(new Bindable<bool>(FlipCatcherPlate));
+                }
+
+                return base.GetConfig<TLookup, TValue>(lookup);
+            }
+        }
+    }
+}

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

@@ -6,8 +6,8 @@ using System.Collections.Generic;
 using System.Linq;
 using NUnit.Framework;
 using osu.Framework.Allocation;
-using osu.Game.Rulesets.Catch.UI;
 using osu.Framework.Graphics;
+using osu.Game.Rulesets.Catch.UI;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Testing;
 using osu.Framework.Utils;
@@ -31,10 +31,10 @@ namespace osu.Game.Rulesets.Catch.Tests
         [Resolved]
         private OsuConfigManager config { get; set; }
 
-        private Container<CaughtObject> droppedObjectContainer;
-
         private TestCatcher catcher;
 
+        private DroppedObjectContainer droppedObjectContainer;
+
         [SetUp]
         public void SetUp() => Schedule(() =>
         {
@@ -43,19 +43,24 @@ namespace osu.Game.Rulesets.Catch.Tests
                 CircleSize = 0,
             };
 
-            var trailContainer = new Container();
+            var trailContainer = new Container
-            droppedObjectContainer = new Container<CaughtObject>();
-            catcher = new TestCatcher(trailContainer, droppedObjectContainer, difficulty);
-
-            Child = new Container
             {
                 Anchor = Anchor.Centre,
+            };
+            droppedObjectContainer = new DroppedObjectContainer();
+            Child = new DependencyProvidingContainer
+            {
+                CachedDependencies = new (Type, object)[]
+                {
+                    (typeof(DroppedObjectContainer), droppedObjectContainer),
+                },
                 Children = new Drawable[]
                 {
-                    trailContainer,
                     droppedObjectContainer,
-                    catcher
+                    catcher = new TestCatcher(trailContainer, difficulty),
-                }
+                    trailContainer
+                },
+                Anchor = Anchor.Centre
             };
         });
 
@@ -188,9 +193,9 @@ namespace osu.Game.Rulesets.Catch.Tests
             AddStep("catch more fruits", () => attemptCatch(() => new Fruit(), 9));
             checkPlate(10);
             AddAssert("caught objects are stacked", () =>
-                catcher.CaughtObjects.All(obj => obj.Y <= Catcher.CAUGHT_FRUIT_VERTICAL_OFFSET) &&
+                catcher.CaughtObjects.All(obj => obj.Y <= 0) &&
-                catcher.CaughtObjects.Any(obj => obj.Y == Catcher.CAUGHT_FRUIT_VERTICAL_OFFSET) &&
+                catcher.CaughtObjects.Any(obj => obj.Y == 0) &&
-                catcher.CaughtObjects.Any(obj => obj.Y < -25));
+                catcher.CaughtObjects.Any(obj => obj.Y < 0));
         }
 
         [Test]
@@ -216,7 +221,7 @@ 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]
@@ -293,8 +298,8 @@ namespace osu.Game.Rulesets.Catch.Tests
         {
             public IEnumerable<CaughtObject> CaughtObjects => this.ChildrenOfType<CaughtObject>();
 
-            public TestCatcher(Container trailsTarget, Container<CaughtObject> droppedObjectTarget, BeatmapDifficulty difficulty)
+            public TestCatcher(Container trailsTarget, BeatmapDifficulty difficulty)
-                : base(trailsTarget, droppedObjectTarget, difficulty)
+                : base(trailsTarget, difficulty)
             {
             }
         }

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

@@ -6,7 +6,6 @@ using NUnit.Framework;
 using osu.Framework.Allocation;
 using osu.Framework.Extensions.IEnumerableExtensions;
 using osu.Framework.Graphics;
-using osu.Framework.Graphics.Containers;
 using osu.Framework.Testing;
 using osu.Framework.Threading;
 using osu.Framework.Utils;
@@ -97,18 +96,12 @@ namespace osu.Game.Rulesets.Catch.Tests
 
             SetContents(_ =>
             {
-                var droppedObjectContainer = new Container<CaughtObject>
-                {
-                    RelativeSizeAxes = Axes.Both
-                };
-
                 return new CatchInputManager(catchRuleset)
                 {
                     RelativeSizeAxes = Axes.Both,
                     Children = new Drawable[]
                     {
-                        droppedObjectContainer,
+                        new TestCatcherArea(beatmapDifficulty)
-                        new TestCatcherArea(droppedObjectContainer, beatmapDifficulty)
                         {
                             Anchor = Anchor.Centre,
                             Origin = Anchor.TopCentre,
@@ -126,9 +119,13 @@ namespace osu.Game.Rulesets.Catch.Tests
 
         private class TestCatcherArea : CatcherArea
         {
-            public TestCatcherArea(Container<CaughtObject> droppedObjectContainer, BeatmapDifficulty beatmapDifficulty)
+            [Cached]
-                : base(droppedObjectContainer, beatmapDifficulty)
+            private readonly DroppedObjectContainer droppedObjectContainer;
+
+            public TestCatcherArea(BeatmapDifficulty beatmapDifficulty)
+                : base(beatmapDifficulty)
             {
+                AddInternal(droppedObjectContainer = new DroppedObjectContainer());
             }
 
             public void ToggleHyperDash(bool status) => MovableCatcher.SetHyperDashState(status ? 2 : 1);

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

@@ -174,8 +174,8 @@ namespace osu.Game.Rulesets.Catch.Tests
 
         private void addToPlayfield(DrawableCatchHitObject drawable)
         {
-            foreach (var mod in SelectedMods.Value.OfType<IApplicableToDrawableHitObjects>())
+            foreach (var mod in SelectedMods.Value.OfType<IApplicableToDrawableHitObject>())
-                mod.ApplyToDrawableHitObjects(new[] { drawable });
+                mod.ApplyToDrawableHitObject(drawable);
 
             drawableRuleset.Playfield.Add(drawable);
         }

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

@@ -118,11 +118,10 @@ namespace osu.Game.Rulesets.Catch.Tests
 
             AddStep("create hyper-dashing catcher", () =>
             {
-                Child = setupSkinHierarchy(catcherArea = new CatcherArea(new Container<CaughtObject>())
+                Child = setupSkinHierarchy(catcherArea = new TestCatcherArea
                 {
                     Anchor = Anchor.Centre,
-                    Origin = Anchor.Centre,
+                    Origin = Anchor.Centre
-                    Scale = new Vector2(4f),
                 }, skin);
             });
 
@@ -139,7 +138,7 @@ namespace osu.Game.Rulesets.Catch.Tests
 
             AddStep("finish hyper-dashing", () =>
             {
-                catcherArea.MovableCatcher.SetHyperDashState(1);
+                catcherArea.MovableCatcher.SetHyperDashState();
                 catcherArea.MovableCatcher.FinishTransforms();
             });
 
@@ -206,5 +205,18 @@ namespace osu.Game.Rulesets.Catch.Tests
             {
             }
         }
+
+        private class TestCatcherArea : CatcherArea
+        {
+            [Cached]
+            private readonly DroppedObjectContainer droppedObjectContainer;
+
+            public TestCatcherArea()
+            {
+                Scale = new Vector2(4f);
+
+                AddInternal(droppedObjectContainer = new DroppedObjectContainer());
+            }
+        }
     }
 }

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

@@ -4,7 +4,7 @@
     <PackageReference Include="Appveyor.TestLogger" Version="2.0.0" />
     <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 Include="NUnit3TestAdapter" Version="4.0.0" />
     <PackageReference Update="Microsoft.EntityFrameworkCore.Sqlite" Version="2.1.4" />
   </ItemGroup>
   <PropertyGroup Label="Project">

osu.Game.Rulesets.Catch/Beatmaps/CatchBeatmapConverter.cs

@@ -23,7 +23,8 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
 
         protected override IEnumerable<CatchHitObject> ConvertHitObject(HitObject obj, IBeatmap beatmap, CancellationToken cancellationToken)
         {
-            var positionData = obj as IHasXPosition;
+            var xPositionData = obj as IHasXPosition;
+            var yPositionData = obj as IHasYPosition;
             var comboData = obj as IHasCombo;
 
             switch (obj)
@@ -36,10 +37,11 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
                         Path = curveData.Path,
                         NodeSamples = curveData.NodeSamples,
                         RepeatCount = curveData.RepeatCount,
-                        X = positionData?.X ?? 0,
+                        X = xPositionData?.X ?? 0,
                         NewCombo = comboData?.NewCombo ?? false,
                         ComboOffset = comboData?.ComboOffset ?? 0,
-                        LegacyLastTickOffset = (obj as IHasLegacyLastTickOffset)?.LegacyLastTickOffset ?? 0
+                        LegacyLastTickOffset = (obj as IHasLegacyLastTickOffset)?.LegacyLastTickOffset ?? 0,
+                        LegacyConvertedY = yPositionData?.Y ?? CatchHitObject.DEFAULT_LEGACY_CONVERT_Y
                     }.Yield();
 
                 case IHasDuration endTime:
@@ -59,7 +61,8 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
                         Samples = obj.Samples,
                         NewCombo = comboData?.NewCombo ?? false,
                         ComboOffset = comboData?.ComboOffset ?? 0,
-                        X = positionData?.X ?? 0
+                        X = xPositionData?.X ?? 0,
+                        LegacyConvertedY = yPositionData?.Y ?? CatchHitObject.DEFAULT_LEGACY_CONVERT_Y
                     }.Yield();
             }
         }

osu.Game.Rulesets.Catch/Beatmaps/CatchBeatmapProcessor.cs

@@ -8,7 +8,6 @@ using osu.Game.Beatmaps;
 using osu.Game.Rulesets.Catch.MathUtils;
 using osu.Game.Rulesets.Catch.Objects;
 using osu.Game.Rulesets.Catch.UI;
-using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Objects.Types;
 
 namespace osu.Game.Rulesets.Catch.Beatmaps
@@ -17,6 +16,8 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
     {
         public const int RNG_SEED = 1337;
 
+        public bool HardRockOffsets { get; set; }
+
         public CatchBeatmapProcessor(IBeatmap beatmap)
             : base(beatmap)
         {
@@ -43,11 +44,10 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
             }
         }
 
-        public static void ApplyPositionOffsets(IBeatmap beatmap, params Mod[] mods)
+        public void ApplyPositionOffsets(IBeatmap beatmap)
         {
             var rng = new FastRandom(RNG_SEED);
 
-            bool shouldApplyHardRockOffset = mods.Any(m => m is ModHardRock);
             float? lastPosition = null;
             double lastStartTime = 0;
 
@@ -58,7 +58,7 @@ namespace osu.Game.Rulesets.Catch.Beatmaps
                 switch (obj)
                 {
                     case Fruit fruit:
-                        if (shouldApplyHardRockOffset)
+                        if (HardRockOffsets)
                             applyHardRockOffset(fruit, ref lastPosition, ref lastStartTime, rng);
                         break;
 

osu.Game.Rulesets.Catch/CatchRuleset.cs

@@ -22,7 +22,9 @@ using osu.Game.Rulesets.Scoring;
 using osu.Game.Scoring;
 using System;
 using osu.Framework.Extensions.EnumExtensions;
+using osu.Game.Rulesets.Catch.Edit;
 using osu.Game.Rulesets.Catch.Skinning.Legacy;
+using osu.Game.Rulesets.Edit;
 using osu.Game.Skinning;
 
 namespace osu.Game.Rulesets.Catch
@@ -175,12 +177,14 @@ namespace osu.Game.Rulesets.Catch
 
         public override DifficultyCalculator CreateDifficultyCalculator(WorkingBeatmap beatmap) => new CatchDifficultyCalculator(this, beatmap);
 
-        public override ISkin CreateLegacySkinProvider(ISkinSource source, IBeatmap beatmap) => new CatchLegacySkinTransformer(source);
+        public override ISkin CreateLegacySkinProvider(ISkin skin, IBeatmap beatmap) => new CatchLegacySkinTransformer(skin);
 
         public override PerformanceCalculator CreatePerformanceCalculator(DifficultyAttributes attributes, ScoreInfo score) => new CatchPerformanceCalculator(this, attributes, score);
 
         public int LegacyID => 2;
 
         public override IConvertibleReplayFrame CreateConvertibleReplayFrame() => new CatchReplayFrame();
+
+        public override HitObjectComposer CreateHitObjectComposer() => new CatchHitObjectComposer(this);
     }
 }

osu.Game.Rulesets.Catch/CatchSkinComponents.cs

@@ -8,9 +8,7 @@ namespace osu.Game.Rulesets.Catch
         Fruit,
         Banana,
         Droplet,
-        CatcherIdle,
+        Catcher,
-        CatcherFail,
-        CatcherKiai,
         CatchComboCounter
     }
 }

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

@@ -7,6 +7,6 @@ namespace osu.Game.Rulesets.Catch.Difficulty
 {
     public class CatchDifficultyAttributes : DifficultyAttributes
     {
-        public double ApproachRate;
+        public double ApproachRate { get; set; }
     }
 }

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/CatchPerformanceCalculator.cs

@@ -4,7 +4,6 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using osu.Framework.Extensions;
 using osu.Game.Rulesets.Difficulty;
 using osu.Game.Rulesets.Mods;
 using osu.Game.Rulesets.Scoring;
@@ -33,15 +32,11 @@ namespace osu.Game.Rulesets.Catch.Difficulty
         {
             mods = Score.Mods;
 
-            fruitsHit = Score.Statistics.GetOrDefault(HitResult.Great);
+            fruitsHit = Score.Statistics.GetValueOrDefault(HitResult.Great);
-            ticksHit = Score.Statistics.GetOrDefault(HitResult.LargeTickHit);
+            ticksHit = Score.Statistics.GetValueOrDefault(HitResult.LargeTickHit);
-            tinyTicksHit = Score.Statistics.GetOrDefault(HitResult.SmallTickHit);
+            tinyTicksHit = Score.Statistics.GetValueOrDefault(HitResult.SmallTickHit);
-            tinyTicksMissed = Score.Statistics.GetOrDefault(HitResult.SmallTickMiss);
+            tinyTicksMissed = Score.Statistics.GetValueOrDefault(HitResult.SmallTickMiss);
-            misses = Score.Statistics.GetOrDefault(HitResult.Miss);
+            misses = Score.Statistics.GetValueOrDefault(HitResult.Miss);
-
-            // Don't count scores made with supposedly unranked mods
-            if (mods.Any(m => !m.Ranked))
-                return 0;
 
             // We are heavily relying on aim in catch the beat
             double value = Math.Pow(5.0 * Math.Max(1.0, Attributes.StarRating / 0.0049) - 4.0, 2.0) / 100000.0;

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/Edit/BananaShowerCompositionTool.cs

@@ -0,0 +1,24 @@
+// 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;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Edit.Tools;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class BananaShowerCompositionTool : HitObjectCompositionTool
+    {
+        public BananaShowerCompositionTool()
+            : base(nameof(BananaShower))
+        {
+        }
+
+        public override Drawable CreateIcon() => new BeatmapStatisticIcon(BeatmapStatisticsIconType.Spinners);
+
+        public override PlacementBlueprint CreatePlacementBlueprint() => new BananaShowerPlacementBlueprint();
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/BananaShowerPlacementBlueprint.cs

@@ -0,0 +1,73 @@
+// 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.Input.Events;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class BananaShowerPlacementBlueprint : CatchPlacementBlueprint<BananaShower>
+    {
+        private readonly TimeSpanOutline outline;
+
+        public BananaShowerPlacementBlueprint()
+        {
+            InternalChild = outline = new TimeSpanOutline();
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            outline.UpdateFrom(HitObjectContainer, HitObject);
+        }
+
+        protected override bool OnMouseDown(MouseDownEvent e)
+        {
+            switch (PlacementActive)
+            {
+                case PlacementState.Waiting:
+                    if (e.Button != MouseButton.Left) break;
+
+                    BeginPlacement(true);
+                    return true;
+
+                case PlacementState.Active:
+                    if (e.Button != MouseButton.Right) break;
+
+                    // If the duration is negative, swap the start and the end time to make the duration positive.
+                    if (HitObject.Duration < 0)
+                    {
+                        HitObject.StartTime = HitObject.EndTime;
+                        HitObject.Duration = -HitObject.Duration;
+                    }
+
+                    EndPlacement(HitObject.Duration > 0);
+                    return true;
+            }
+
+            return base.OnMouseDown(e);
+        }
+
+        public override void UpdateTimeAndPosition(SnapResult result)
+        {
+            base.UpdateTimeAndPosition(result);
+
+            if (!(result.Time is double time)) return;
+
+            switch (PlacementActive)
+            {
+                case PlacementState.Waiting:
+                    HitObject.StartTime = time;
+                    break;
+
+                case PlacementState.Active:
+                    HitObject.EndTime = time;
+                    break;
+            }
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/BananaShowerSelectionBlueprint.cs

@@ -0,0 +1,15 @@
+// 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.Catch.Objects;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class BananaShowerSelectionBlueprint : CatchSelectionBlueprint<BananaShower>
+    {
+        public BananaShowerSelectionBlueprint(BananaShower hitObject)
+            : base(hitObject)
+        {
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/CatchPlacementBlueprint.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 osu.Framework.Allocation;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.UI;
+using osu.Game.Rulesets.UI.Scrolling;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class CatchPlacementBlueprint<THitObject> : PlacementBlueprint
+        where THitObject : CatchHitObject, new()
+    {
+        protected new THitObject HitObject => (THitObject)base.HitObject;
+
+        protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
+
+        [Resolved]
+        private Playfield playfield { get; set; }
+
+        public CatchPlacementBlueprint()
+            : base(new THitObject())
+        {
+        }
+
+        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => true;
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/CatchSelectionBlueprint.cs

@@ -0,0 +1,39 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.UI;
+using osu.Game.Rulesets.UI.Scrolling;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public abstract class CatchSelectionBlueprint<THitObject> : HitObjectSelectionBlueprint<THitObject>
+        where THitObject : CatchHitObject
+    {
+        protected override bool AlwaysShowWhenSelected => true;
+
+        public override Vector2 ScreenSpaceSelectionPoint
+        {
+            get
+            {
+                Vector2 position = CatchHitObjectUtils.GetStartPosition(HitObjectContainer, HitObject);
+                return HitObjectContainer.ToScreenSpace(position + new Vector2(0, HitObjectContainer.DrawHeight));
+            }
+        }
+
+        public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => SelectionQuad.Contains(screenSpacePos);
+
+        protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
+
+        [Resolved]
+        private Playfield playfield { get; set; }
+
+        protected CatchSelectionBlueprint(THitObject hitObject)
+            : base(hitObject)
+        {
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/FruitOutline.cs

@@ -0,0 +1,34 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Game.Graphics;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Catch.Skinning.Default;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
+{
+    public class FruitOutline : CompositeDrawable
+    {
+        public FruitOutline()
+        {
+            Anchor = Anchor.BottomLeft;
+            Origin = Anchor.Centre;
+            InternalChild = new BorderPiece();
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour osuColour)
+        {
+            Colour = osuColour.Yellow;
+        }
+
+        public void UpdateFrom(CatchHitObject hitObject)
+        {
+            Scale = new Vector2(hitObject.Scale);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/NestedOutlineContainer.cs

@@ -0,0 +1,48 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Primitives;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.UI.Scrolling;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
+{
+    public class NestedOutlineContainer : CompositeDrawable
+    {
+        private readonly List<CatchHitObject> nestedHitObjects = new List<CatchHitObject>();
+
+        public NestedOutlineContainer()
+        {
+            Anchor = Anchor.BottomLeft;
+        }
+
+        public void UpdateNestedObjectsFrom(ScrollingHitObjectContainer hitObjectContainer, CatchHitObject parentHitObject)
+        {
+            nestedHitObjects.Clear();
+            nestedHitObjects.AddRange(parentHitObject.NestedHitObjects
+                                                     .OfType<CatchHitObject>()
+                                                     .Where(h => !(h is TinyDroplet)));
+
+            while (nestedHitObjects.Count < InternalChildren.Count)
+                RemoveInternal(InternalChildren[^1]);
+
+            while (InternalChildren.Count < nestedHitObjects.Count)
+                AddInternal(new FruitOutline());
+
+            for (int i = 0; i < nestedHitObjects.Count; i++)
+            {
+                var hitObject = nestedHitObjects[i];
+                var outline = (FruitOutline)InternalChildren[i];
+                outline.Position = CatchHitObjectUtils.GetStartPosition(hitObjectContainer, hitObject) - Position;
+                outline.UpdateFrom(hitObject);
+                outline.Scale *= hitObject is Droplet ? 0.5f : 1;
+            }
+        }
+
+        protected override bool ComputeIsMaskedAway(RectangleF maskingBounds) => false;
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/ScrollingPath.cs

@@ -0,0 +1,77 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using System.Linq;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Lines;
+using osu.Framework.Graphics.Primitives;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.UI.Scrolling;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
+{
+    public class ScrollingPath : CompositeDrawable
+    {
+        private readonly Path drawablePath;
+
+        private readonly List<(double Distance, float X)> vertices = new List<(double, float)>();
+
+        public ScrollingPath()
+        {
+            Anchor = Anchor.BottomLeft;
+
+            InternalChildren = new Drawable[]
+            {
+                drawablePath = new SmoothPath
+                {
+                    PathRadius = 2,
+                    Alpha = 0.5f
+                },
+            };
+        }
+
+        public void UpdatePathFrom(ScrollingHitObjectContainer hitObjectContainer, JuiceStream hitObject)
+        {
+            double distanceToYFactor = -hitObjectContainer.LengthAtTime(hitObject.StartTime, hitObject.StartTime + 1 / hitObject.Velocity);
+
+            computeDistanceXs(hitObject);
+            drawablePath.Vertices = vertices
+                                    .Select(v => new Vector2(v.X, (float)(v.Distance * distanceToYFactor)))
+                                    .ToArray();
+            drawablePath.OriginPosition = drawablePath.PositionInBoundingBox(Vector2.Zero);
+        }
+
+        private void computeDistanceXs(JuiceStream hitObject)
+        {
+            vertices.Clear();
+
+            var sliderVertices = new List<Vector2>();
+            hitObject.Path.GetPathToProgress(sliderVertices, 0, 1);
+
+            if (sliderVertices.Count == 0)
+                return;
+
+            double distance = 0;
+            Vector2 lastPosition = Vector2.Zero;
+
+            for (int repeat = 0; repeat < hitObject.RepeatCount + 1; repeat++)
+            {
+                foreach (var position in sliderVertices)
+                {
+                    distance += Vector2.Distance(lastPosition, position);
+                    lastPosition = position;
+
+                    vertices.Add((distance, position.X));
+                }
+
+                sliderVertices.Reverse();
+            }
+        }
+
+        // Because this has 0x0 size, the contents are otherwise masked away if the start position is outside the screen.
+        protected override bool ComputeIsMaskedAway(RectangleF maskingBounds) => false;
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/Components/TimeSpanOutline.cs

@@ -0,0 +1,63 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Game.Graphics;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.UI.Scrolling;
+using osuTK.Graphics;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints.Components
+{
+    public class TimeSpanOutline : CompositeDrawable
+    {
+        private const float border_width = 4;
+
+        private const float opacity_when_empty = 0.5f;
+
+        private bool isEmpty = true;
+
+        public TimeSpanOutline()
+        {
+            Anchor = Origin = Anchor.BottomLeft;
+            RelativeSizeAxes = Axes.X;
+
+            Masking = true;
+            BorderThickness = border_width;
+            Alpha = opacity_when_empty;
+
+            // A box is needed to make the border visible.
+            InternalChild = new Box
+            {
+                RelativeSizeAxes = Axes.Both,
+                Colour = Color4.Transparent
+            };
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(OsuColour osuColour)
+        {
+            BorderColour = osuColour.Yellow;
+        }
+
+        public void UpdateFrom(ScrollingHitObjectContainer hitObjectContainer, BananaShower hitObject)
+        {
+            float startY = hitObjectContainer.PositionAtTime(hitObject.StartTime);
+            float endY = hitObjectContainer.PositionAtTime(hitObject.EndTime);
+
+            Y = Math.Max(startY, endY);
+            float height = Math.Abs(startY - endY);
+
+            bool wasEmpty = isEmpty;
+            isEmpty = height == 0;
+            if (wasEmpty != isEmpty)
+                this.FadeTo(isEmpty ? opacity_when_empty : 1f, 150);
+
+            Height = Math.Max(height, border_width);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/FruitPlacementBlueprint.cs

@@ -0,0 +1,51 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Input.Events;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osuTK.Input;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class FruitPlacementBlueprint : CatchPlacementBlueprint<Fruit>
+    {
+        private readonly FruitOutline outline;
+
+        public FruitPlacementBlueprint()
+        {
+            InternalChild = outline = new FruitOutline();
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            BeginPlacement();
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            outline.Position = CatchHitObjectUtils.GetStartPosition(HitObjectContainer, HitObject);
+            outline.UpdateFrom(HitObject);
+        }
+
+        protected override bool OnMouseDown(MouseDownEvent e)
+        {
+            if (e.Button != MouseButton.Left) return base.OnMouseDown(e);
+
+            EndPlacement(true);
+            return true;
+        }
+
+        public override void UpdateTimeAndPosition(SnapResult result)
+        {
+            base.UpdateTimeAndPosition(result);
+
+            HitObject.X = ToLocalSpace(result.ScreenSpacePosition).X;
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/FruitSelectionBlueprint.cs

@@ -0,0 +1,29 @@
+// 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.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class FruitSelectionBlueprint : CatchSelectionBlueprint<Fruit>
+    {
+        private readonly FruitOutline outline;
+
+        public FruitSelectionBlueprint(Fruit hitObject)
+            : base(hitObject)
+        {
+            InternalChild = outline = new FruitOutline();
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            if (!IsSelected) return;
+
+            outline.Position = CatchHitObjectUtils.GetStartPosition(HitObjectContainer, HitObject);
+            outline.UpdateFrom(HitObject);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/Blueprints/JuiceStreamSelectionBlueprint.cs

@@ -0,0 +1,91 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Linq;
+using osu.Framework.Allocation;
+using osu.Framework.Caching;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Primitives;
+using osu.Game.Rulesets.Catch.Edit.Blueprints.Components;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Objects;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit.Blueprints
+{
+    public class JuiceStreamSelectionBlueprint : CatchSelectionBlueprint<JuiceStream>
+    {
+        public override Quad SelectionQuad => HitObjectContainer.ToScreenSpace(getBoundingBox().Offset(new Vector2(0, HitObjectContainer.DrawHeight)));
+
+        private float minNestedX;
+        private float maxNestedX;
+
+        private readonly ScrollingPath scrollingPath;
+
+        private readonly NestedOutlineContainer nestedOutlineContainer;
+
+        private readonly Cached pathCache = new Cached();
+
+        public JuiceStreamSelectionBlueprint(JuiceStream hitObject)
+            : base(hitObject)
+        {
+            InternalChildren = new Drawable[]
+            {
+                scrollingPath = new ScrollingPath(),
+                nestedOutlineContainer = new NestedOutlineContainer()
+            };
+        }
+
+        [BackgroundDependencyLoader]
+        private void load()
+        {
+            HitObject.DefaultsApplied += onDefaultsApplied;
+            computeObjectBounds();
+        }
+
+        protected override void Update()
+        {
+            base.Update();
+
+            if (!IsSelected) return;
+
+            nestedOutlineContainer.Position = scrollingPath.Position = CatchHitObjectUtils.GetStartPosition(HitObjectContainer, HitObject);
+
+            if (pathCache.IsValid) return;
+
+            scrollingPath.UpdatePathFrom(HitObjectContainer, HitObject);
+            nestedOutlineContainer.UpdateNestedObjectsFrom(HitObjectContainer, HitObject);
+
+            pathCache.Validate();
+        }
+
+        private void onDefaultsApplied(HitObject _)
+        {
+            computeObjectBounds();
+            pathCache.Invalidate();
+        }
+
+        private void computeObjectBounds()
+        {
+            minNestedX = HitObject.NestedHitObjects.OfType<CatchHitObject>().Min(nested => nested.OriginalX) - HitObject.OriginalX;
+            maxNestedX = HitObject.NestedHitObjects.OfType<CatchHitObject>().Max(nested => nested.OriginalX) - HitObject.OriginalX;
+        }
+
+        private RectangleF getBoundingBox()
+        {
+            float left = HitObject.OriginalX + minNestedX;
+            float right = HitObject.OriginalX + maxNestedX;
+            float top = HitObjectContainer.PositionAtTime(HitObject.EndTime);
+            float bottom = HitObjectContainer.PositionAtTime(HitObject.StartTime);
+            float objectRadius = CatchHitObject.OBJECT_RADIUS * HitObject.Scale;
+            return new RectangleF(left, top, right - left, bottom - top).Inflate(objectRadius);
+        }
+
+        protected override void Dispose(bool isDisposing)
+        {
+            base.Dispose(isDisposing);
+
+            HitObject.DefaultsApplied -= onDefaultsApplied;
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/CatchBlueprintContainer.cs

@@ -0,0 +1,38 @@
+// 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.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Screens.Edit.Compose.Components;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class CatchBlueprintContainer : ComposeBlueprintContainer
+    {
+        public CatchBlueprintContainer(CatchHitObjectComposer composer)
+            : base(composer)
+        {
+        }
+
+        protected override SelectionHandler<HitObject> CreateSelectionHandler() => new CatchSelectionHandler();
+
+        public override HitObjectSelectionBlueprint CreateHitObjectBlueprintFor(HitObject hitObject)
+        {
+            switch (hitObject)
+            {
+                case Fruit fruit:
+                    return new FruitSelectionBlueprint(fruit);
+
+                case JuiceStream juiceStream:
+                    return new JuiceStreamSelectionBlueprint(juiceStream);
+
+                case BananaShower bananaShower:
+                    return new BananaShowerSelectionBlueprint(bananaShower);
+            }
+
+            return base.CreateHitObjectBlueprintFor(hitObject);
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/CatchEditorPlayfield.cs

@@ -0,0 +1,27 @@
+// 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.Beatmaps;
+using osu.Game.Rulesets.Catch.UI;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class CatchEditorPlayfield : CatchPlayfield
+    {
+        // TODO fixme: the size of the catcher is not changed when circle size is changed in setup screen.
+        public CatchEditorPlayfield(BeatmapDifficulty difficulty)
+            : base(difficulty)
+        {
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            // TODO: honor "hit animation" setting?
+            CatcherArea.MovableCatcher.CatchFruitOnPlate = false;
+
+            // TODO: disable hit lighting as well
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/CatchHitObjectComposer.cs

@@ -0,0 +1,54 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using osu.Framework.Allocation;
+using osu.Framework.Graphics;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Edit.Tools;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.UI;
+using osu.Game.Screens.Edit.Compose.Components;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class CatchHitObjectComposer : HitObjectComposer<CatchHitObject>
+    {
+        public CatchHitObjectComposer(CatchRuleset ruleset)
+            : base(ruleset)
+        {
+        }
+
+        [BackgroundDependencyLoader]
+        private void load()
+        {
+            LayerBelowRuleset.Add(new PlayfieldBorder
+            {
+                RelativeSizeAxes = Axes.Both,
+                PlayfieldBorderStyle = { Value = PlayfieldBorderStyle.Corners }
+            });
+        }
+
+        protected override DrawableRuleset<CatchHitObject> CreateDrawableRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod> mods = null) =>
+            new DrawableCatchEditorRuleset(ruleset, beatmap, mods);
+
+        protected override IReadOnlyList<HitObjectCompositionTool> CompositionTools => new HitObjectCompositionTool[]
+        {
+            new FruitCompositionTool(),
+            new BananaShowerCompositionTool()
+        };
+
+        public override SnapResult SnapScreenSpacePositionToValidTime(Vector2 screenSpacePosition)
+        {
+            var result = base.SnapScreenSpacePositionToValidTime(screenSpacePosition);
+            // TODO: implement position snap
+            result.ScreenSpacePosition.X = screenSpacePosition.X;
+            return result;
+        }
+
+        protected override ComposeBlueprintContainer CreateBlueprintContainer() => new CatchBlueprintContainer(this);
+    }
+}

osu.Game.Rulesets.Catch/Edit/CatchHitObjectUtils.cs

@@ -0,0 +1,24 @@
+// 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.Catch.Objects;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.UI.Scrolling;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    /// <summary>
+    /// Utility functions used by the editor.
+    /// </summary>
+    public static class CatchHitObjectUtils
+    {
+        /// <summary>
+        /// Get the position of the hit object in the playfield based on <see cref="CatchHitObject.OriginalX"/> and <see cref="HitObject.StartTime"/>.
+        /// </summary>
+        public static Vector2 GetStartPosition(ScrollingHitObjectContainer hitObjectContainer, CatchHitObject hitObject)
+        {
+            return new Vector2(hitObject.OriginalX, hitObjectContainer.PositionAtTime(hitObject.StartTime));
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/CatchSelectionHandler.cs

@@ -0,0 +1,116 @@
+// 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.Allocation;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Catch.UI;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.UI;
+using osu.Game.Rulesets.UI.Scrolling;
+using osu.Game.Screens.Edit.Compose.Components;
+using osuTK;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class CatchSelectionHandler : EditorSelectionHandler
+    {
+        protected ScrollingHitObjectContainer HitObjectContainer => (ScrollingHitObjectContainer)playfield.HitObjectContainer;
+
+        [Resolved]
+        private Playfield playfield { get; set; }
+
+        public override bool HandleMovement(MoveSelectionEvent<HitObject> moveEvent)
+        {
+            var blueprint = moveEvent.Blueprint;
+            Vector2 originalPosition = HitObjectContainer.ToLocalSpace(blueprint.ScreenSpaceSelectionPoint);
+            Vector2 targetPosition = HitObjectContainer.ToLocalSpace(blueprint.ScreenSpaceSelectionPoint + moveEvent.ScreenSpaceDelta);
+
+            float deltaX = targetPosition.X - originalPosition.X;
+            deltaX = limitMovement(deltaX, EditorBeatmap.SelectedHitObjects);
+
+            if (deltaX == 0)
+            {
+                // Even if there is no positional change, there may be a time change.
+                return true;
+            }
+
+            EditorBeatmap.PerformOnSelection(h =>
+            {
+                if (!(h is CatchHitObject hitObject)) return;
+
+                hitObject.OriginalX += deltaX;
+
+                // Move the nested hit objects to give an instant result before nested objects are recreated.
+                foreach (var nested in hitObject.NestedHitObjects.OfType<CatchHitObject>())
+                    nested.OriginalX += deltaX;
+            });
+
+            return true;
+        }
+
+        /// <summary>
+        /// Limit positional movement of the objects by the constraint that moved objects should stay in bounds.
+        /// </summary>
+        /// <param name="deltaX">The positional movement.</param>
+        /// <param name="movingObjects">The objects to be moved.</param>
+        /// <returns>The positional movement with the restriction applied.</returns>
+        private float limitMovement(float deltaX, IEnumerable<HitObject> movingObjects)
+        {
+            float minX = float.PositiveInfinity;
+            float maxX = float.NegativeInfinity;
+
+            foreach (float x in movingObjects.SelectMany(getOriginalPositions))
+            {
+                minX = Math.Min(minX, x);
+                maxX = Math.Max(maxX, x);
+            }
+
+            // To make an object with position `x` stay in bounds after `deltaX` movement, `0 <= x + deltaX <= WIDTH` should be satisfied.
+            // Subtracting `x`, we get `-x <= deltaX <= WIDTH - x`.
+            // We only need to apply the inequality to extreme values of `x`.
+            float lowerBound = -minX;
+            float upperBound = CatchPlayfield.WIDTH - maxX;
+            // The inequality may be unsatisfiable if the objects were already out of bounds.
+            // In that case, don't move objects at all.
+            if (lowerBound > upperBound)
+                return 0;
+
+            return Math.Clamp(deltaX, lowerBound, upperBound);
+        }
+
+        /// <summary>
+        /// Enumerate X positions that should be contained in-bounds after move offset is applied.
+        /// </summary>
+        private IEnumerable<float> getOriginalPositions(HitObject hitObject)
+        {
+            switch (hitObject)
+            {
+                case Fruit fruit:
+                    yield return fruit.OriginalX;
+
+                    break;
+
+                case JuiceStream juiceStream:
+                    foreach (var nested in juiceStream.NestedHitObjects.OfType<CatchHitObject>())
+                    {
+                        // Even if `OriginalX` is outside the playfield, tiny droplets can be moved inside the playfield after the random offset application.
+                        if (!(nested is TinyDroplet))
+                            yield return nested.OriginalX;
+                    }
+
+                    break;
+
+                case BananaShower _:
+                    // A banana shower occupies the whole screen width.
+                    // If the selection contains a banana shower, the selection cannot be moved horizontally.
+                    yield return 0;
+                    yield return CatchPlayfield.WIDTH;
+
+                    break;
+            }
+        }
+    }
+}

osu.Game.Rulesets.Catch/Edit/DrawableCatchEditorRuleset.cs

@@ -0,0 +1,21 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Catch.UI;
+using osu.Game.Rulesets.Mods;
+using osu.Game.Rulesets.UI;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class DrawableCatchEditorRuleset : DrawableCatchRuleset
+    {
+        public DrawableCatchEditorRuleset(Ruleset ruleset, IBeatmap beatmap, IReadOnlyList<Mod> mods = null)
+            : base(ruleset, beatmap, mods)
+        {
+        }
+
+        protected override Playfield CreatePlayfield() => new CatchEditorPlayfield(Beatmap.BeatmapInfo.BaseDifficulty);
+    }
+}

osu.Game.Rulesets.Catch/Edit/FruitCompositionTool.cs

@@ -0,0 +1,24 @@
+// 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;
+using osu.Game.Beatmaps;
+using osu.Game.Rulesets.Catch.Edit.Blueprints;
+using osu.Game.Rulesets.Catch.Objects;
+using osu.Game.Rulesets.Edit;
+using osu.Game.Rulesets.Edit.Tools;
+
+namespace osu.Game.Rulesets.Catch.Edit
+{
+    public class FruitCompositionTool : HitObjectCompositionTool
+    {
+        public FruitCompositionTool()
+            : base(nameof(Fruit))
+        {
+        }
+
+        public override Drawable CreateIcon() => new BeatmapStatisticIcon(BeatmapStatisticsIconType.Circles);
+
+        public override PlacementBlueprint CreatePlacementBlueprint() => new FruitPlacementBlueprint();
+    }
+}

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/CatchModDifficultyAdjust.cs

@@ -5,39 +5,35 @@ using System.Linq;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
 using osu.Game.Configuration;
+using osu.Game.Rulesets.Catch.Beatmaps;
 using osu.Game.Rulesets.Mods;
 
 namespace osu.Game.Rulesets.Catch.Mods
 {
-    public class CatchModDifficultyAdjust : ModDifficultyAdjust
+    public class CatchModDifficultyAdjust : ModDifficultyAdjust, IApplicableToBeatmapProcessor
     {
-        [SettingSource("Circle Size", "Override a beatmap's set CS.", FIRST_SETTING_ORDER - 1)]
+        [SettingSource("Circle Size", "Override a beatmap's set CS.", FIRST_SETTING_ORDER - 1, SettingControlType = typeof(DifficultyAdjustSettingsControl))]
-        public BindableNumber<float> CircleSize { get; } = new BindableFloatWithLimitExtension
+        public DifficultyBindable CircleSize { get; } = new DifficultyBindable
         {
             Precision = 0.1f,
             MinValue = 1,
             MaxValue = 10,
-            Default = 5,
+            ExtendedMaxValue = 11,
-            Value = 5,
+            ReadCurrentFromDifficulty = diff => diff.CircleSize,
         };
 
-        [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1)]
+        [SettingSource("Approach Rate", "Override a beatmap's set AR.", LAST_SETTING_ORDER + 1, SettingControlType = typeof(DifficultyAdjustSettingsControl))]
-        public BindableNumber<float> ApproachRate { get; } = new BindableFloatWithLimitExtension
+        public DifficultyBindable ApproachRate { get; } = new DifficultyBindable
         {
             Precision = 0.1f,
             MinValue = 1,
             MaxValue = 10,
-            Default = 5,
+            ExtendedMaxValue = 11,
-            Value = 5,
+            ReadCurrentFromDifficulty = diff => diff.ApproachRate,
         };
 
-        protected override void ApplyLimits(bool extended)
+        [SettingSource("Spicy Patterns", "Adjust the patterns as if Hard Rock is enabled.")]
-        {
+        public BindableBool HardRockOffsets { get; } = new BindableBool();
-            base.ApplyLimits(extended);
-
-            CircleSize.MaxValue = extended ? 11 : 10;
-            ApproachRate.MaxValue = extended ? 11 : 10;
-        }
 
         public override string SettingDescription
         {
@@ -45,30 +41,30 @@ namespace osu.Game.Rulesets.Catch.Mods
             {
                 string circleSize = CircleSize.IsDefault ? string.Empty : $"CS {CircleSize.Value:N1}";
                 string approachRate = ApproachRate.IsDefault ? string.Empty : $"AR {ApproachRate.Value:N1}";
+                string spicyPatterns = HardRockOffsets.IsDefault ? string.Empty : "Spicy patterns";
 
                 return string.Join(", ", new[]
                 {
                     circleSize,
                     base.SettingDescription,
-                    approachRate
+                    approachRate,
+                    spicyPatterns,
                 }.Where(s => !string.IsNullOrEmpty(s)));
             }
         }
 
-        protected override void TransferSettings(BeatmapDifficulty difficulty)
-        {
-            base.TransferSettings(difficulty);
-
-            TransferSetting(CircleSize, difficulty.CircleSize);
-            TransferSetting(ApproachRate, difficulty.ApproachRate);
-        }
-
         protected override void ApplySettings(BeatmapDifficulty difficulty)
         {
             base.ApplySettings(difficulty);
 
-            ApplySetting(CircleSize, cs => difficulty.CircleSize = cs);
+            if (CircleSize.Value != null) difficulty.CircleSize = CircleSize.Value.Value;
-            ApplySetting(ApproachRate, ar => difficulty.ApproachRate = ar);
+            if (ApproachRate.Value != null) difficulty.ApproachRate = ApproachRate.Value.Value;
+        }
+
+        public void ApplyToBeatmapProcessor(IBeatmapProcessor beatmapProcessor)
+        {
+            var catchProcessor = (CatchBeatmapProcessor)beatmapProcessor;
+            catchProcessor.HardRockOffsets = HardRockOffsets.Value;
         }
     }
 }

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

@@ -7,11 +7,14 @@ using osu.Game.Rulesets.Catch.Beatmaps;
 
 namespace osu.Game.Rulesets.Catch.Mods
 {
-    public class CatchModHardRock : ModHardRock, IApplicableToBeatmap
+    public class CatchModHardRock : ModHardRock, IApplicableToBeatmapProcessor
     {
         public override double ScoreMultiplier => 1.12;
-        public override bool Ranked => true;
 
-        public void ApplyToBeatmap(IBeatmap beatmap) => CatchBeatmapProcessor.ApplyPositionOffsets(beatmap, this);
+        public void ApplyToBeatmapProcessor(IBeatmapProcessor beatmapProcessor)
+        {
+            var catchProcessor = (CatchBeatmapProcessor)beatmapProcessor;
+            catchProcessor.HardRockOffsets = true;
+        }
     }
 }

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/Mods/CatchModRelax.cs

@@ -33,13 +33,13 @@ namespace osu.Game.Rulesets.Catch.Mods
 
         private class MouseInputHelper : Drawable, IKeyBindingHandler<CatchAction>, IRequireHighFrequencyMousePosition
         {
-            private readonly Catcher catcher;
+            private readonly CatcherArea catcherArea;
 
             public override bool ReceivePositionalInputAt(Vector2 screenSpacePos) => true;
 
             public MouseInputHelper(CatchPlayfield playfield)
             {
-                catcher = playfield.CatcherArea.MovableCatcher;
+                catcherArea = playfield.CatcherArea;
                 RelativeSizeAxes = Axes.Both;
             }
 
@@ -52,7 +52,7 @@ namespace osu.Game.Rulesets.Catch.Mods
 
             protected override bool OnMouseMove(MouseMoveEvent e)
             {
-                catcher.UpdatePosition(e.MousePosition.X / DrawSize.X * CatchPlayfield.WIDTH);
+                catcherArea.SetCatcherPosition(e.MousePosition.X / DrawSize.X * CatchPlayfield.WIDTH);
                 return base.OnMouseMove(e);
             }
         }

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

@@ -9,6 +9,7 @@ using osu.Game.Audio;
 using osu.Game.Rulesets.Catch.Judgements;
 using osu.Game.Rulesets.Judgements;
 using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Skinning;
 using osu.Game.Utils;
 using osuTK.Graphics;
 
@@ -31,7 +32,7 @@ namespace osu.Game.Rulesets.Catch.Objects
         }
 
         // override any external colour changes with banananana
-        Color4 IHasComboInformation.GetComboColour(IReadOnlyList<Color4> comboColours) => getBananaColour();
+        Color4 IHasComboInformation.GetComboColour(ISkin skin) => getBananaColour();
 
         private Color4 getBananaColour()
         {

osu.Game.Rulesets.Catch/Objects/CatchHitObject.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 Newtonsoft.Json;
 using osu.Framework.Bindables;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.ControlPoints;
@@ -8,10 +9,11 @@ using osu.Game.Rulesets.Catch.UI;
 using osu.Game.Rulesets.Objects;
 using osu.Game.Rulesets.Objects.Types;
 using osu.Game.Rulesets.Scoring;
+using osuTK;
 
 namespace osu.Game.Rulesets.Catch.Objects
 {
-    public abstract class CatchHitObject : HitObject, IHasXPosition, IHasComboInformation
+    public abstract class CatchHitObject : HitObject, IHasPosition, IHasComboInformation
     {
         public const float OBJECT_RADIUS = 64;
 
@@ -20,13 +22,16 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// <summary>
         /// The horizontal position of the hit object between 0 and <see cref="CatchPlayfield.WIDTH"/>.
         /// </summary>
+        /// <remarks>
+        /// Only setter is exposed.
+        /// Use <see cref="OriginalX"/> or <see cref="EffectiveX"/> to get the horizontal position.
+        /// </remarks>
+        [JsonIgnore]
         public float X
         {
             set => OriginalXBindable.Value = value;
         }
 
-        float IHasXPosition.X => OriginalXBindable.Value;
-
         public readonly Bindable<float> XOffsetBindable = new Bindable<float>();
 
         /// <summary>
@@ -34,6 +39,7 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// </summary>
         public float XOffset
         {
+            get => XOffsetBindable.Value;
             set => XOffsetBindable.Value = value;
         }
 
@@ -44,7 +50,11 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// This value is the original <see cref="X"/> value specified in the beatmap, not affected by the beatmap processing.
         /// Use <see cref="EffectiveX"/> for a gameplay.
         /// </remarks>
-        public float OriginalX => OriginalXBindable.Value;
+        public float OriginalX
+        {
+            get => OriginalXBindable.Value;
+            set => OriginalXBindable.Value = value;
+        }
 
         /// <summary>
         /// The effective horizontal position of the hit object between 0 and <see cref="CatchPlayfield.WIDTH"/>.
@@ -53,9 +63,9 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// This value is the original <see cref="X"/> value plus the offset applied by the beatmap processing.
         /// Use <see cref="OriginalX"/> if a value not affected by the offset is desired.
         /// </remarks>
-        public float EffectiveX => OriginalXBindable.Value + XOffsetBindable.Value;
+        public float EffectiveX => OriginalX + XOffset;
 
-        public double TimePreempt = 1000;
+        public double TimePreempt { get; set; } = 1000;
 
         public readonly Bindable<int> IndexInBeatmapBindable = new Bindable<int>();
 
@@ -120,5 +130,24 @@ namespace osu.Game.Rulesets.Catch.Objects
         }
 
         protected override HitWindows CreateHitWindows() => HitWindows.Empty;
+
+        #region Hit object conversion
+
+        // The half of the height of the osu! playfield.
+        public const float DEFAULT_LEGACY_CONVERT_Y = 192;
+
+        /// <summary>
+        /// The Y position of the hit object is not used in the normal osu!catch gameplay.
+        /// It is preserved to maximize the backward compatibility with the legacy editor, in which the mappers use the Y position to organize the patterns.
+        /// </summary>
+        public float LegacyConvertedY { get; set; } = DEFAULT_LEGACY_CONVERT_Y;
+
+        float IHasXPosition.X => OriginalX;
+
+        float IHasYPosition.Y => LegacyConvertedY;
+
+        Vector2 IHasPosition.Position => new Vector2(OriginalX, LegacyConvertedY);
+
+        #endregion
     }
 }

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/Objects/JuiceStream.cs

@@ -5,6 +5,7 @@ using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Threading;
+using Newtonsoft.Json;
 using osu.Game.Audio;
 using osu.Game.Beatmaps;
 using osu.Game.Beatmaps.ControlPoints;
@@ -25,7 +26,10 @@ namespace osu.Game.Rulesets.Catch.Objects
 
         public int RepeatCount { get; set; }
 
+        [JsonIgnore]
         public double Velocity { get; private set; }
+
+        [JsonIgnore]
         public double TickDistance { get; private set; }
 
         /// <summary>
@@ -113,6 +117,7 @@ namespace osu.Game.Rulesets.Catch.Objects
 
         public float EndX => OriginalX + this.CurvePositionAt(1).X;
 
+        [JsonIgnore]
         public double Duration
         {
             get => this.SpanCount() * Path.Distance / Velocity;

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

@@ -0,0 +1,340 @@
+// 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.Utils;
+using osu.Game.Rulesets.Objects;
+using osu.Game.Rulesets.Objects.Types;
+using osuTK;
+
+#nullable enable
+
+namespace osu.Game.Rulesets.Catch.Objects
+{
+    /// <summary>
+    /// Represents the path of a juice stream.
+    /// <para>
+    /// A <see cref="JuiceStream"/> holds a legacy <see cref="SliderPath"/> as the representation of the path.
+    /// However, the <see cref="SliderPath"/> representation is difficult to work with.
+    /// This <see cref="JuiceStreamPath"/> represents the path in a more convenient way, a polyline connecting list of <see cref="JuiceStreamPathVertex"/>s.
+    /// </para>
+    /// <para>
+    /// The path can be regarded as a function from the closed interval <c>[Vertices[0].Distance, Vertices[^1].Distance]</c> to the x position, given by <see cref="PositionAtDistance"/>.
+    /// To ensure the path is convertible to a <see cref="SliderPath"/>, the slope of the function must not be more than <c>1</c> everywhere,
+    /// and this slope condition is always maintained as an invariant.
+    /// </para>
+    /// </summary>
+    public class JuiceStreamPath
+    {
+        /// <summary>
+        /// The height of legacy osu!standard playfield.
+        /// The sliders converted by <see cref="ConvertToSliderPath"/> are vertically contained in this height.
+        /// </summary>
+        internal const float OSU_PLAYFIELD_HEIGHT = 384;
+
+        /// <summary>
+        /// The list of vertices of the path, which is represented as a polyline connecting the vertices.
+        /// </summary>
+        public IReadOnlyList<JuiceStreamPathVertex> Vertices => vertices;
+
+        /// <summary>
+        /// The current version number.
+        /// This starts from <c>1</c> and incremented whenever this <see cref="JuiceStreamPath"/> is modified.
+        /// </summary>
+        public int InvalidationID { get; private set; } = 1;
+
+        /// <summary>
+        /// The difference between first vertex's <see cref="JuiceStreamPathVertex.Distance"/> and last vertex's <see cref="JuiceStreamPathVertex.Distance"/>.
+        /// </summary>
+        public double Distance => vertices[^1].Distance - vertices[0].Distance;
+
+        /// <remarks>
+        /// This list should always be non-empty.
+        /// </remarks>
+        private readonly List<JuiceStreamPathVertex> vertices = new List<JuiceStreamPathVertex>
+        {
+            new JuiceStreamPathVertex()
+        };
+
+        /// <summary>
+        /// Compute the x-position of the path at the given <paramref name="distance"/>.
+        /// </summary>
+        /// <remarks>
+        /// When the given distance is outside of the path, the x position at the corresponding endpoint is returned,
+        /// </remarks>
+        public float PositionAtDistance(double distance)
+        {
+            int index = vertexIndexAtDistance(distance);
+            return positionAtDistance(distance, index);
+        }
+
+        /// <summary>
+        /// Remove all vertices of this path, then add a new vertex <c>(0, 0)</c>.
+        /// </summary>
+        public void Clear()
+        {
+            vertices.Clear();
+            vertices.Add(new JuiceStreamPathVertex());
+            invalidate();
+        }
+
+        /// <summary>
+        /// Insert a vertex at given <paramref name="distance"/>.
+        /// The <see cref="PositionAtDistance"/> is used as the position of the new vertex.
+        /// Thus, the set of points of the path is not changed (up to floating-point precision).
+        /// </summary>
+        /// <returns>The index of the new vertex.</returns>
+        public int InsertVertex(double distance)
+        {
+            if (!double.IsFinite(distance))
+                throw new ArgumentOutOfRangeException(nameof(distance));
+
+            int index = vertexIndexAtDistance(distance);
+            float x = positionAtDistance(distance, index);
+            vertices.Insert(index, new JuiceStreamPathVertex(distance, x));
+
+            invalidate();
+            return index;
+        }
+
+        /// <summary>
+        /// Move the vertex of given <paramref name="index"/> to the given position <paramref name="newX"/>.
+        /// When the distances between vertices are too small for the new vertex positions, the adjacent vertices are moved towards <paramref name="newX"/>.
+        /// </summary>
+        public void SetVertexPosition(int index, float newX)
+        {
+            if (index < 0 || index >= vertices.Count)
+                throw new ArgumentOutOfRangeException(nameof(index));
+
+            if (!float.IsFinite(newX))
+                throw new ArgumentOutOfRangeException(nameof(newX));
+
+            var newVertex = new JuiceStreamPathVertex(vertices[index].Distance, newX);
+
+            for (int i = index - 1; i >= 0 && !canConnect(vertices[i], newVertex); i--)
+            {
+                float clampedX = clampToConnectablePosition(newVertex, vertices[i]);
+                vertices[i] = new JuiceStreamPathVertex(vertices[i].Distance, clampedX);
+            }
+
+            for (int i = index + 1; i < vertices.Count; i++)
+            {
+                float clampedX = clampToConnectablePosition(newVertex, vertices[i]);
+                vertices[i] = new JuiceStreamPathVertex(vertices[i].Distance, clampedX);
+            }
+
+            vertices[index] = newVertex;
+
+            invalidate();
+        }
+
+        /// <summary>
+        /// Add a new vertex at given <paramref name="distance"/> and position.
+        /// Adjacent vertices are moved when necessary in the same way as <see cref="SetVertexPosition"/>.
+        /// </summary>
+        public void Add(double distance, float x)
+        {
+            int index = InsertVertex(distance);
+            SetVertexPosition(index, x);
+        }
+
+        /// <summary>
+        /// Remove all vertices that satisfy the given <paramref name="predicate"/>.
+        /// </summary>
+        /// <remarks>
+        /// If all vertices are removed, a new vertex <c>(0, 0)</c> is added.
+        /// </remarks>
+        /// <param name="predicate">The predicate to determine whether a vertex should be removed given the vertex and its index in the path.</param>
+        /// <returns>The number of removed vertices.</returns>
+        public int RemoveVertices(Func<JuiceStreamPathVertex, int, bool> predicate)
+        {
+            int index = 0;
+            int removeCount = vertices.RemoveAll(vertex => predicate(vertex, index++));
+
+            if (vertices.Count == 0)
+                vertices.Add(new JuiceStreamPathVertex());
+
+            if (removeCount != 0)
+                invalidate();
+
+            return removeCount;
+        }
+
+        /// <summary>
+        /// Recreate this path by using difference set of vertices at given distances.
+        /// In addition to the given <paramref name="sampleDistances"/>, the first vertex and the last vertex are always added to the new path.
+        /// New vertices use the positions on the original path. Thus, <see cref="PositionAtDistance"/>s at <paramref name="sampleDistances"/> are preserved.
+        /// </summary>
+        public void ResampleVertices(IEnumerable<double> sampleDistances)
+        {
+            var sampledVertices = new List<JuiceStreamPathVertex>();
+
+            foreach (double distance in sampleDistances)
+            {
+                if (!double.IsFinite(distance))
+                    throw new ArgumentOutOfRangeException(nameof(sampleDistances));
+
+                double clampedDistance = Math.Clamp(distance, vertices[0].Distance, vertices[^1].Distance);
+                float x = PositionAtDistance(clampedDistance);
+                sampledVertices.Add(new JuiceStreamPathVertex(clampedDistance, x));
+            }
+
+            sampledVertices.Sort();
+
+            // The first vertex and the last vertex are always used in the result.
+            vertices.RemoveRange(1, vertices.Count - (vertices.Count == 1 ? 1 : 2));
+            vertices.InsertRange(1, sampledVertices);
+
+            invalidate();
+        }
+
+        /// <summary>
+        /// Convert a <see cref="SliderPath"/> to list of vertices and write the result to this <see cref="JuiceStreamPath"/>.
+        /// </summary>
+        /// <remarks>
+        /// Duplicated vertices are automatically removed.
+        /// </remarks>
+        public void ConvertFromSliderPath(SliderPath sliderPath)
+        {
+            var sliderPathVertices = new List<Vector2>();
+            sliderPath.GetPathToProgress(sliderPathVertices, 0, 1);
+
+            double distance = 0;
+
+            vertices.Clear();
+            vertices.Add(new JuiceStreamPathVertex(0, sliderPathVertices.FirstOrDefault().X));
+
+            for (int i = 1; i < sliderPathVertices.Count; i++)
+            {
+                distance += Vector2.Distance(sliderPathVertices[i - 1], sliderPathVertices[i]);
+
+                if (!Precision.AlmostEquals(vertices[^1].Distance, distance))
+                    vertices.Add(new JuiceStreamPathVertex(distance, sliderPathVertices[i].X));
+            }
+
+            invalidate();
+        }
+
+        /// <summary>
+        /// Convert the path of this <see cref="JuiceStreamPath"/> to a <see cref="SliderPath"/> and write the result to <paramref name="sliderPath"/>.
+        /// The resulting slider is "folded" to make it vertically contained in the playfield `(0..<see cref="OSU_PLAYFIELD_HEIGHT"/>)` assuming the slider start position is <paramref name="sliderStartY"/>.
+        /// </summary>
+        public void ConvertToSliderPath(SliderPath sliderPath, float sliderStartY)
+        {
+            const float margin = 1;
+
+            // Note: these two variables and `sliderPath` are modified by the local functions.
+            double currentDistance = 0;
+            Vector2 lastPosition = new Vector2(vertices[0].X, 0);
+
+            sliderPath.ControlPoints.Clear();
+            sliderPath.ControlPoints.Add(new PathControlPoint(lastPosition));
+
+            for (int i = 1; i < vertices.Count; i++)
+            {
+                sliderPath.ControlPoints[^1].Type.Value = PathType.Linear;
+
+                float deltaX = vertices[i].X - lastPosition.X;
+                double length = vertices[i].Distance - currentDistance;
+
+                // Should satisfy `deltaX^2 + deltaY^2 = length^2`.
+                // By invariants, the expression inside the `sqrt` is (almost) non-negative.
+                double deltaY = Math.Sqrt(Math.Max(0, length * length - (double)deltaX * deltaX));
+
+                // When `deltaY` is small, one segment is always enough.
+                // This case is handled separately to prevent divide-by-zero.
+                if (deltaY <= OSU_PLAYFIELD_HEIGHT / 2 - margin)
+                {
+                    float nextX = vertices[i].X;
+                    float nextY = (float)(lastPosition.Y + getYDirection() * deltaY);
+                    addControlPoint(nextX, nextY);
+                    continue;
+                }
+
+                // When `deltaY` is large or when the slider velocity is fast, the segment must be partitioned to subsegments to stay in bounds.
+                for (double currentProgress = 0; currentProgress < deltaY;)
+                {
+                    double nextProgress = Math.Min(currentProgress + getMaxDeltaY(), deltaY);
+                    float nextX = (float)(vertices[i - 1].X + nextProgress / deltaY * deltaX);
+                    float nextY = (float)(lastPosition.Y + getYDirection() * (nextProgress - currentProgress));
+                    addControlPoint(nextX, nextY);
+                    currentProgress = nextProgress;
+                }
+            }
+
+            int getYDirection()
+            {
+                float lastSliderY = sliderStartY + lastPosition.Y;
+                return lastSliderY < OSU_PLAYFIELD_HEIGHT / 2 ? 1 : -1;
+            }
+
+            float getMaxDeltaY()
+            {
+                float lastSliderY = sliderStartY + lastPosition.Y;
+                return Math.Max(lastSliderY, OSU_PLAYFIELD_HEIGHT - lastSliderY) - margin;
+            }
+
+            void addControlPoint(float nextX, float nextY)
+            {
+                Vector2 nextPosition = new Vector2(nextX, nextY);
+                sliderPath.ControlPoints.Add(new PathControlPoint(nextPosition));
+                currentDistance += Vector2.Distance(lastPosition, nextPosition);
+                lastPosition = nextPosition;
+            }
+        }
+
+        /// <summary>
+        /// Find the index at which a new vertex with <paramref name="distance"/> can be inserted.
+        /// </summary>
+        private int vertexIndexAtDistance(double distance)
+        {
+            // The position of `(distance, Infinity)` is uniquely determined because infinite positions are not allowed.
+            int i = vertices.BinarySearch(new JuiceStreamPathVertex(distance, float.PositiveInfinity));
+            return i < 0 ? ~i : i;
+        }
+
+        /// <summary>
+        /// Compute the position at the given <paramref name="distance"/>, assuming <paramref name="index"/> is the vertex index returned by <see cref="vertexIndexAtDistance"/>.
+        /// </summary>
+        private float positionAtDistance(double distance, int index)
+        {
+            if (index <= 0)
+                return vertices[0].X;
+            if (index >= vertices.Count)
+                return vertices[^1].X;
+
+            double length = vertices[index].Distance - vertices[index - 1].Distance;
+            if (Precision.AlmostEquals(length, 0))
+                return vertices[index].X;
+
+            float deltaX = vertices[index].X - vertices[index - 1].X;
+
+            return (float)(vertices[index - 1].X + deltaX * ((distance - vertices[index - 1].Distance) / length));
+        }
+
+        /// <summary>
+        /// Check the two vertices can connected directly while satisfying the slope condition.
+        /// </summary>
+        private bool canConnect(JuiceStreamPathVertex vertex1, JuiceStreamPathVertex vertex2, float allowance = 0)
+        {
+            double xDistance = Math.Abs((double)vertex2.X - vertex1.X);
+            float length = (float)Math.Abs(vertex2.Distance - vertex1.Distance);
+            return xDistance <= length + allowance;
+        }
+
+        /// <summary>
+        /// Move the position of <paramref name="movableVertex"/> towards the position of <paramref name="fixedVertex"/>
+        /// until the vertex pair satisfies the condition <see cref="canConnect"/>.
+        /// </summary>
+        /// <returns>The resulting position of <paramref name="movableVertex"/>.</returns>
+        private float clampToConnectablePosition(JuiceStreamPathVertex fixedVertex, JuiceStreamPathVertex movableVertex)
+        {
+            float length = (float)Math.Abs(movableVertex.Distance - fixedVertex.Distance);
+            return Math.Clamp(movableVertex.X, fixedVertex.X - length, fixedVertex.X + length);
+        }
+
+        private void invalidate() => InvalidationID++;
+    }
+}

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

@@ -0,0 +1,33 @@
+// 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;
+
+#nullable enable
+
+namespace osu.Game.Rulesets.Catch.Objects
+{
+    /// <summary>
+    /// A vertex of a <see cref="JuiceStreamPath"/>.
+    /// </summary>
+    public readonly struct JuiceStreamPathVertex : IComparable<JuiceStreamPathVertex>
+    {
+        public readonly double Distance;
+
+        public readonly float X;
+
+        public JuiceStreamPathVertex(double distance, float x)
+        {
+            Distance = distance;
+            X = x;
+        }
+
+        public int CompareTo(JuiceStreamPathVertex other)
+        {
+            int c = Distance.CompareTo(other.Distance);
+            return c != 0 ? c : X.CompareTo(other.X);
+        }
+
+        public override string ToString() => $"({Distance}, {X})";
+    }
+}

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

@@ -1,9 +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.Collections.Generic;
+using Newtonsoft.Json;
 using osu.Framework.Bindables;
 using osu.Game.Rulesets.Objects.Types;
+using osu.Game.Skinning;
 using osuTK.Graphics;
 
 namespace osu.Game.Rulesets.Catch.Objects
@@ -33,6 +34,7 @@ namespace osu.Game.Rulesets.Catch.Objects
         /// <summary>
         /// The target fruit if we are to initiate a hyperdash.
         /// </summary>
+        [JsonIgnore]
         public CatchHitObject HyperDashTarget
         {
             get => hyperDashTarget;
@@ -43,6 +45,6 @@ namespace osu.Game.Rulesets.Catch.Objects
             }
         }
 
-        Color4 IHasComboInformation.GetComboColour(IReadOnlyList<Color4> comboColours) => comboColours[(IndexInBeatmap + 1) % comboColours.Count];
+        Color4 IHasComboInformation.GetComboColour(ISkin skin) => IHasComboInformation.GetSkinComboColour(this, skin, IndexInBeatmap + 1);
     }
 }

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/CatchSkinConfiguration.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.Skinning
+{
+    public enum CatchSkinConfiguration
+    {
+        /// <summary>
+        /// Whether the contents of the catcher plate should be visually flipped when the catcher direction is changed.
+        /// </summary>
+        FlipCatcherPlate
+    }
+}

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/DefaultCatcher.cs

@@ -0,0 +1,52 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Collections.Generic;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Sprites;
+using osu.Framework.Graphics.Textures;
+using osu.Game.Rulesets.Catch.UI;
+
+namespace osu.Game.Rulesets.Catch.Skinning.Default
+{
+    public class DefaultCatcher : CompositeDrawable
+    {
+        public Bindable<CatcherAnimationState> CurrentState { get; } = new Bindable<CatcherAnimationState>();
+
+        private readonly Sprite sprite;
+
+        private readonly Dictionary<CatcherAnimationState, Texture> textures = new Dictionary<CatcherAnimationState, Texture>();
+
+        public DefaultCatcher()
+        {
+            RelativeSizeAxes = Axes.Both;
+            InternalChild = sprite = new Sprite
+            {
+                Anchor = Anchor.TopCentre,
+                Origin = Anchor.TopCentre,
+                RelativeSizeAxes = Axes.Both,
+                FillMode = FillMode.Fit
+            };
+        }
+
+        [BackgroundDependencyLoader]
+        private void load(TextureStore store, Bindable<CatcherAnimationState> currentState)
+        {
+            CurrentState.BindTo(currentState);
+
+            textures[CatcherAnimationState.Idle] = store.Get(@"Gameplay/catch/fruit-catcher-idle");
+            textures[CatcherAnimationState.Fail] = store.Get(@"Gameplay/catch/fruit-catcher-fail");
+            textures[CatcherAnimationState.Kiai] = store.Get(@"Gameplay/catch/fruit-catcher-kiai");
+        }
+
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            CurrentState.BindValueChanged(state => sprite.Texture = textures[state.NewValue], true);
+        }
+    }
+}