Replace Lidgren encryption stuff with Libsodium (#2646)

Co-authored-by: Paul <ritter.paul1@googlemail.com>

.github/CODEOWNERS

@@ -1,7 +1,20 @@
 # Last match in file takes precedence.
 
+# Ping for all PRs
+* @Acruid @PJB3005 @Silvertorch5
+
+/Robust.*/Audio/Midi/ @Zumorica
+
+/Robust.Client.NameGenerator @PaulRitter
+/Robust.Client.Injectors @PaulRitter
+/Robust.Generators @PaulRitter
+/Robust.Analyzers @PaulRitter
+/Robust.*/GameStates @PaulRitter
+/Robust.Shared/Analyzers @PaulRitter
+/Robust.*/Serialization @PaulRitter @DrSmugleaf
+/Robust.*/Prototypes @PaulRitter
+/Robust.Shared/GameObjects/ComponentDependencies @PaulRitter
+/Robust.*/Containers @PaulRitter
+
 # Be they Fluent translations or Freemarker templates, I know them both!
 *.ftl @RemieRichards
-
-# Ping for all PRs
-* @Acruid @PJB3005 @Silvertorch5

.github/workflows/benchmarks.yml

@@ -0,0 +1,33 @@
+name: Benchmarks
+#on:
+#  push
+  #schedule:
+  #  - cron: '0 5 * * *'
+  #push:
+  #  tags:
+  #    - 'v*'
+
+env:
+  ROBUST_BENCHMARKS_ENABLE_SQL: 1
+  ROBUST_BENCHMARKS_SQL_ADDRESS: ${{ secrets.BENCHMARKS_WRITE_ADDRESS }}
+  ROBUST_BENCHMARKS_SQL_PORT: ${{ secrets.BENCHMARKS_WRITE_PORT }}
+  ROBUST_BENCHMARKS_SQL_USER: ${{ secrets.BENCHMARKS_WRITE_USER }}
+  ROBUST_BENCHMARKS_SQL_PASSWORD: ${{ secrets.BENCHMARKS_WRITE_PASSWORD }}
+  ROBUST_BENCHMARKS_SQL_DATABASE: benchmarks
+
+jobs:
+  benchmark:
+    name: Run Benchmarks
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          submodules: true
+      - name: Setup .NET Core
+        uses: actions/setup-dotnet@v1
+        with:
+          dotnet-version: 6.0.x
+      - name: Install dependencies
+        run: dotnet restore
+      - name: Run benchmark
+        run: cd Robust.Benchmarks && sudo dotnet run --filter '*' --configuration Release

.github/workflows/build-docfx.yml

@@ -0,0 +1,34 @@
+name: Build & Publish DocFX
+
+on:
+  schedule:
+    - cron: "0 0 * * 0"
+jobs:
+  docfx:
+   runs-on: ubuntu-latest
+   steps: 
+    - uses: actions/checkout@v2
+      with:
+        submodules: true
+
+    - name: Setup .NET Core
+      uses: actions/setup-dotnet@v1
+      with:
+        dotnet-version: 6.0.x
+        
+    - name: Install dependencies
+      run: dotnet restore
+      
+    - name: Build Project
+      run: dotnet build --no-restore /p:WarningsAsErrors=nullable
+
+    - name: Build DocFX
+      uses: nikeee/docfx-action@v1.0.0      
+      with:
+        args: Robust.Docfx/docfx.json
+    
+    - name: Publish Docfx Documentation on GitHub Pages
+      uses: maxheld83/ghpages@master
+      env:
+        BUILD_DIR: Robust.Docfx/_robust-site 
+        GH_PAT: ${{ secrets.GH_PAT }} 

.github/workflows/build-test.yml

@@ -22,10 +22,12 @@ jobs:
     - name: Setup .NET Core
       uses: actions/setup-dotnet@v1
       with:
-        dotnet-version: 6.0.100
+        dotnet-version: 6.0.x
     - name: Install dependencies
       run: dotnet restore
     - name: Build
       run: dotnet build --no-restore /p:WarningsAsErrors=nullable
     - name: Test Engine
       run: dotnet test --no-build Robust.UnitTesting/Robust.UnitTesting.csproj -v n
+ 
+

.gitignore

@@ -76,3 +76,5 @@ MSBuild/Robust.Custom.targets
 
 
 release/
+Robust.Docfx/*-site
+Robust.Docfx/api

MSBuild/Robust.Engine.Version.props

@@ -1,4 +1,4 @@
 <Project>
     <!-- This file automatically reset by Tools/version.py -->
-    <PropertyGroup><Version>0.8.21</Version></PropertyGroup>
+    <PropertyGroup><Version>0.8.86</Version></PropertyGroup>
 </Project>

Robust.Analyzers/Diagnostics.cs

@@ -1,10 +1,14 @@
 using Microsoft.CodeAnalysis;
 
-namespace Robust.Generators
+namespace Robust.Analyzers;
+
+public static class Diagnostics
 {
-    public static class Diagnostics
-    {
-        public static SuppressionDescriptor MeansImplicitAssignment =>
-            new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");
-    }
+    public const string IdExplicitInterface = "RA0000";
+    public const string IdSerializable = "RA0001";
+    public const string IdFriend = "RA0002";
+    public const string IdExplicitVirtual = "RA0003";
+
+    public static SuppressionDescriptor MeansImplicitAssignment =>
+        new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");
 }

Robust.Analyzers/ExplicitInterfaceAnalyzer.cs

@@ -24,14 +24,14 @@ namespace Robust.Analyzers
             SyntaxKind.OverrideKeyword
         };
 
-        public const string DiagnosticId = "RA0000";
-
-        private const string Title = "No explicit interface specified";
-        private const string MessageFormat = "No explicit interface specified";
-        private const string Description = "Make sure to specify the interface in your method-declaration.";
-        private const string Category = "Usage";
-
-        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Warning, isEnabledByDefault: true, description: Description);
+        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new(
+            Diagnostics.IdExplicitInterface,
+            "No explicit interface specified",
+            "No explicit interface specified",
+            "Usage",
+            DiagnosticSeverity.Warning,
+            isEnabledByDefault: true,
+            description: "Make sure to specify the interface in your method-declaration.");
 
         private const string RequiresExplicitImplementationAttributeMetadataName =
             "Robust.Shared.Analyzers.RequiresExplicitImplementationAttribute";

Robust.Analyzers/ExplicitVirtualAnalyzer.cs

@@ -0,0 +1,176 @@
+using System.Collections.Immutable;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+using Microsoft.CodeAnalysis.Diagnostics;
+
+namespace Robust.Analyzers;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public sealed class ExplicitVirtualAnalyzer : DiagnosticAnalyzer
+{
+    internal const string Attribute = "Robust.Shared.Analyzers.VirtualAttribute";
+
+    [SuppressMessage("ReSharper", "RS2008")]
+    private static readonly DiagnosticDescriptor Rule = new(
+        Diagnostics.IdExplicitVirtual,
+        "Class must be explicitly marked as [Virtual], abstract, static or sealed",
+        "Class must be explicitly marked as [Virtual], abstract, static or sealed",
+        "Usage",
+        DiagnosticSeverity.Warning,
+        isEnabledByDefault: true,
+        description: "Class must be explicitly marked as [Virtual], abstract, static or sealed.");
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+        context.EnableConcurrentExecution();
+        context.RegisterSyntaxNodeAction(AnalyzeNode, SyntaxKind.ClassDeclaration);
+    }
+
+    private static bool HasAttribute(INamedTypeSymbol namedTypeSymbol, INamedTypeSymbol attrSymbol)
+    {
+        return namedTypeSymbol.GetAttributes()
+            .Any(a => SymbolEqualityComparer.Default.Equals(a.AttributeClass, attrSymbol));
+    }
+
+    private static void AnalyzeNode(SyntaxNodeAnalysisContext context)
+    {
+        var attrSymbol = context.Compilation.GetTypeByMetadataName(Attribute);
+        var classDecl = (ClassDeclarationSyntax)context.Node;
+        var classSymbol = context.SemanticModel.GetDeclaredSymbol(classDecl);
+        if (classSymbol == null)
+            return;
+
+        if (classSymbol.IsSealed || classSymbol.IsAbstract || classSymbol.IsStatic)
+            return;
+
+        if (HasAttribute(classSymbol, attrSymbol))
+            return;
+
+        var diag = Diagnostic.Create(Rule, classDecl.Keyword.GetLocation());
+        context.ReportDiagnostic(diag);
+    }
+}
+
+// Doesn't work as I'd hoped: Roslyn doesn't provide an API for global usings and I can't get batch changes to work.
+/*
+[ExportCodeFixProvider(LanguageNames.CSharp)]
+public sealed class ExplicitVirtualCodeFixProvider : CodeFixProvider
+{
+    private const string TitleSealed = "Annotate class as sealed.";
+    private const string TitleVirtual = "Annotate class as [Virtual].";
+    private const string TitleAbstract = "Annotate class as abstract.";
+    private const string TitleStatic = "Annotate class as static.";
+
+    public override async Task RegisterCodeFixesAsync(CodeFixContext context)
+    {
+        var root = await context.Document.GetSyntaxRootAsync(context.CancellationToken);
+
+        foreach (var diagnostic in context.Diagnostics)
+        {
+            var span = diagnostic.Location.SourceSpan;
+            var classDecl = root.FindToken(span.Start).Parent.AncestorsAndSelf().OfType<ClassDeclarationSyntax>()
+                .First();
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleVirtual,
+                    c => FixVirtualAsync(context.Document, classDecl, c),
+                    TitleVirtual),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleStatic,
+                    c => FixStaticAsync(context.Document, classDecl, c),
+                    TitleStatic),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleSealed,
+                    c => FixSealedAsync(context.Document, classDecl, c),
+                    TitleSealed),
+                diagnostic);
+
+            context.RegisterCodeFix(
+                CodeAction.Create(
+                    TitleAbstract,
+                    c => FixAbstractAsync(context.Document, classDecl, c),
+                    TitleAbstract),
+                diagnostic);
+        }
+    }
+
+    private async Task<Document> FixVirtualAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var ns = "Robust.Shared.Analyzers";
+        var attrib = SyntaxFactory.Attribute(SyntaxFactory.ParseName("Virtual"));
+
+        var newClassDecl = classDecl.AddAttributeLists(
+            SyntaxFactory.AttributeList(SyntaxFactory.SeparatedList(new[] { attrib })));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        var options = await document.GetOptionsAsync(cancellationToken);
+
+        if (root.Usings.All(u => u.Name.ToString() != ns))
+        {
+            root = root.AddUsings(SyntaxFactory.UsingDirective(SyntaxFactory.ParseName(ns)));
+        }
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixStaticAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.StaticKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixAbstractAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.AbstractKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    private async Task<Document> FixSealedAsync(
+        Document document,
+        ClassDeclarationSyntax classDecl,
+        CancellationToken cancellationToken)
+    {
+        var newClassDecl = classDecl.AddModifiers(SyntaxFactory.Token(SyntaxKind.SealedKeyword));
+
+        var root = (CompilationUnitSyntax)await document.GetSyntaxRootAsync(cancellationToken);
+        root = root.ReplaceNode(classDecl, newClassDecl);
+
+        return document.WithSyntaxRoot(root);
+    }
+
+    public override FixAllProvider GetFixAllProvider() => WellKnownFixAllProviders.BatchFixer;
+    public override ImmutableArray<string> FixableDiagnosticIds => ImmutableArray.Create(Diagnostics.IdExplicitVirtual);
+}
+*/

Robust.Analyzers/FriendAnalyzer.cs

@@ -14,15 +14,15 @@ namespace Robust.Analyzers
     {
         const string FriendAttribute = "Robust.Shared.Analyzers.FriendAttribute";
 
-        public const string DiagnosticId = "RA0002";
-
-        private const string Title = "Tried to access friend-only member";
-        private const string MessageFormat = "Tried to access member \"{0}\" in class \"{1}\" which can only be accessed by friend classes";
-        private const string Description = "Make sure to specify the accessing class in the friends attribute.";
-        private const string Category = "Usage";
-
         [SuppressMessage("ReSharper", "RS2008")]
-        private static readonly DiagnosticDescriptor Rule = new (DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Error, true, Description);
+        private static readonly DiagnosticDescriptor Rule = new (
+            Diagnostics.IdFriend,
+            "Tried to access friend-only member",
+            "Tried to access member \"{0}\" in class \"{1}\" which can only be accessed by friend classes",
+            "Usage",
+            DiagnosticSeverity.Error,
+            true,
+            "Make sure to specify the accessing class in the friends attribute.");
 
         public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
 

Robust.Analyzers/MeansImplicitAssigmentSuppressor.cs

@@ -1,9 +1,7 @@
-using System;
 using System.Collections.Immutable;
 using System.Linq;
 using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.Diagnostics;
-using Robust.Generators;
 
 namespace Robust.Analyzers
 {

Robust.Analyzers/Robust.Analyzers.csproj

@@ -2,13 +2,13 @@
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
-    <LangVersion>9</LangVersion>
+    <LangVersion>10</LangVersion>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="3.8.0" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.2" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="3.8.0" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Workspaces.Common" Version="4.0.1" />
   </ItemGroup>
 
 </Project>

Robust.Analyzers/SerializableAnalyzer.cs

@@ -17,19 +17,21 @@ namespace Robust.Analyzers
     public class SerializableAnalyzer : DiagnosticAnalyzer
     {
         // Metadata of the analyzer
-        public const string DiagnosticId = "RA0001";
 
         // You could use LocalizedString but it's a little more complicated for this sample
-        private const string Title = "Class not marked as (Net)Serializable";
-        private const string MessageFormat = "Class not marked as (Net)Serializable";
-        private const string Description = "The class should be marked as (Net)Serializable.";
-        private const string Category = "Usage";
 
         private const string RequiresSerializableAttributeMetadataName = "Robust.Shared.Analyzers.RequiresSerializableAttribute";
         private const string SerializableAttributeMetadataName = "System.SerializableAttribute";
         private const string NetSerializableAttributeMetadataName = "Robust.Shared.Serialization.NetSerializableAttribute";
 
-        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new DiagnosticDescriptor(DiagnosticId, Title, MessageFormat, Category, DiagnosticSeverity.Warning, isEnabledByDefault: true, description: Description);
+        [SuppressMessage("ReSharper", "RS2008")] private static readonly DiagnosticDescriptor Rule = new(
+            Diagnostics.IdSerializable,
+            "Class not marked as (Net)Serializable",
+            "Class not marked as (Net)Serializable",
+            "Usage",
+            DiagnosticSeverity.Warning,
+            isEnabledByDefault: true,
+            description: "The class should be marked as (Net)Serializable.");
 
         public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
 
@@ -139,7 +141,8 @@ namespace Robust.Analyzers
             return document.WithSyntaxRoot(root);
         }
 
-        public sealed override ImmutableArray<string> FixableDiagnosticIds => ImmutableArray.Create(SerializableAnalyzer.DiagnosticId);
+        public sealed override ImmutableArray<string> FixableDiagnosticIds
+            => ImmutableArray.Create(Diagnostics.IdSerializable);
 
         public override FixAllProvider GetFixAllProvider()
         {

Robust.Benchmarks/Configs/DefaultSQLConfig.cs

@@ -0,0 +1,53 @@
+using System.Collections.Generic;
+using System.Globalization;
+using BenchmarkDotNet.Analysers;
+using BenchmarkDotNet.Columns;
+using BenchmarkDotNet.Configs;
+using BenchmarkDotNet.Diagnosers;
+using BenchmarkDotNet.Exporters;
+using BenchmarkDotNet.Filters;
+using BenchmarkDotNet.Jobs;
+using BenchmarkDotNet.Loggers;
+using BenchmarkDotNet.Order;
+using BenchmarkDotNet.Reports;
+using BenchmarkDotNet.Validators;
+using Robust.Benchmarks.Exporters;
+
+namespace Robust.Benchmarks.Configs;
+
+public sealed class DefaultSQLConfig : IConfig
+{
+    public static readonly IConfig Instance = new DefaultSQLConfig();
+
+    private DefaultSQLConfig(){}
+
+    public IEnumerable<IExporter> GetExporters()
+    {
+        yield return SQLExporter.Default;
+    }
+
+    public IEnumerable<IColumnProvider> GetColumnProviders() => DefaultConfig.Instance.GetColumnProviders();
+
+    public IEnumerable<ILogger> GetLoggers() => DefaultConfig.Instance.GetLoggers();
+
+    public IEnumerable<IDiagnoser> GetDiagnosers() => DefaultConfig.Instance.GetDiagnosers();
+
+    public IEnumerable<IAnalyser> GetAnalysers() => DefaultConfig.Instance.GetAnalysers();
+
+    public IEnumerable<Job> GetJobs() => DefaultConfig.Instance.GetJobs();
+
+    public IEnumerable<IValidator> GetValidators() => DefaultConfig.Instance.GetValidators();
+
+    public IEnumerable<HardwareCounter> GetHardwareCounters() => DefaultConfig.Instance.GetHardwareCounters();
+
+    public IEnumerable<IFilter> GetFilters() => DefaultConfig.Instance.GetFilters();
+
+    public IEnumerable<BenchmarkLogicalGroupRule> GetLogicalGroupRules() => DefaultConfig.Instance.GetLogicalGroupRules();
+
+    public IOrderer Orderer => DefaultConfig.Instance.Orderer!;
+    public SummaryStyle SummaryStyle => DefaultConfig.Instance.SummaryStyle;
+    public ConfigUnionRule UnionRule => DefaultConfig.Instance.UnionRule;
+    public string ArtifactsPath => DefaultConfig.Instance.ArtifactsPath;
+    public CultureInfo CultureInfo => DefaultConfig.Instance.CultureInfo!;
+    public ConfigOptions Options => DefaultConfig.Instance.Options;
+}

Robust.Benchmarks/EntityManager/AddRemoveComponentBenchmark.cs

@@ -0,0 +1,54 @@
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class AddRemoveComponentBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        var coords = new MapCoordinates(0, 0, new MapId(1));
+        _simulation.AddMap(coords.MapId);
+
+        for (var i = 0; i < N; i++)
+        {
+            _entityManager.SpawnEntity(null, coords);
+        }
+    }
+
+    [Benchmark]
+    public void AddRemoveComponent()
+    {
+        for (var i = 2; i <= N+1; i++)
+        {
+            var uid = new EntityUid(i);
+            _entityManager.AddComponent<A>(uid);
+            _entityManager.RemoveComponent<A>(uid);
+        }
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/EntityManager/GetComponentBenchmark.cs

@@ -0,0 +1,61 @@
+using System;
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class GetComponentBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    public A[] Comps = default!;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        Comps = new A[N+2];
+
+        var coords = new MapCoordinates(0, 0, new MapId(1));
+        _simulation.AddMap(coords.MapId);
+
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, coords);
+            _entityManager.AddComponent<A>(uid);
+        }
+    }
+
+    [Benchmark]
+    public A[] GetComponent()
+    {
+        for (var i = 2; i <= N+1; i++)
+        {
+            Comps[i] = _entityManager.GetComponent<A>(new EntityUid(i));
+        }
+
+        // Return something so the JIT doesn't optimize out all the GetComponent calls.
+        return Comps;
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/EntityManager/SpawnDeleteEntityBenchmark.cs

@@ -0,0 +1,62 @@
+using BenchmarkDotNet.Attributes;
+using JetBrains.Annotations;
+using Robust.Shared.Analyzers;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.UnitTesting.Server;
+
+namespace Robust.Benchmarks.EntityManager;
+
+[Virtual]
+public class SpawnDeleteEntityBenchmark
+{
+    private ISimulation _simulation = default!;
+    private IEntityManager _entityManager = default!;
+
+    private MapCoordinates _mapCoords = MapCoordinates.Nullspace;
+    private EntityCoordinates _entCoords = EntityCoordinates.Invalid;
+
+    [UsedImplicitly]
+    [Params(1, 10, 100, 1000)]
+    public int N;
+
+    [GlobalSetup]
+    public void GlobalSetup()
+    {
+        _simulation = RobustServerSimulation
+            .NewSimulation()
+            .RegisterComponents(f => f.RegisterClass<A>())
+            .InitializeInstance();
+
+        _entityManager = _simulation.Resolve<IEntityManager>();
+
+        _mapCoords = new MapCoordinates(0, 0, new MapId(1));
+        var uid = _simulation.AddMap(_mapCoords.MapId);
+        _entCoords = new EntityCoordinates(uid, 0, 0);
+    }
+
+    [Benchmark(Baseline = true)]
+    public void SpawnDeleteEntityMapCoords()
+    {
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, _mapCoords);
+            _entityManager.DeleteEntity(uid);
+        }
+    }
+
+    [Benchmark]
+    public void SpawnDeleteEntityEntCoords()
+    {
+        for (var i = 0; i < N; i++)
+        {
+            var uid = _entityManager.SpawnEntity(null, _entCoords);
+            _entityManager.DeleteEntity(uid);
+        }
+    }
+
+    [ComponentProtoName("A")]
+    public sealed class A : Component
+    {
+    }
+}

Robust.Benchmarks/Exporters/SQLExporter.cs

@@ -0,0 +1,143 @@
+using System;
+using System.Collections.Generic;
+using System.ComponentModel.DataAnnotations;
+using System.ComponentModel.DataAnnotations.Schema;
+using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using BenchmarkDotNet.Exporters;
+using BenchmarkDotNet.Loggers;
+using BenchmarkDotNet.Mathematics;
+using BenchmarkDotNet.Reports;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Design;
+using Npgsql;
+
+namespace Robust.Benchmarks.Exporters;
+
+public sealed class SQLExporter : IExporter
+{
+    public static readonly IExporter Default = new SQLExporter();
+
+    private SQLExporter(){}
+
+    public void ExportToLog(Summary summary, ILogger logger)
+    {
+        Export(summary, logger);
+    }
+
+    public IEnumerable<string> ExportToFiles(Summary summary, ILogger consoleLogger)
+    {
+        Export(summary, consoleLogger);
+        return Array.Empty<string>();
+    }
+
+    private bool TryGetEnvironmentVariable(string name, ILogger logger, [NotNullWhen(true)] out string? value)
+    {
+        value = Environment.GetEnvironmentVariable(name);
+        if (value == null)
+            logger.WriteError($"ROBUST_BENCHMARKS_ENABLE_SQL is set, but {name} is missing.");
+        return value != null;
+    }
+
+    private void Export(Summary summary, ILogger logger)
+    {
+        if (!TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_ADDRESS", logger, out var address) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_PORT", logger, out var rawPort) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_USER", logger, out var user) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_PASSWORD", logger, out var password) ||
+            !TryGetEnvironmentVariable("ROBUST_BENCHMARKS_SQL_DATABASE", logger, out var db) ||
+            !TryGetEnvironmentVariable("GITHUB_SHA", logger, out var gitHash))
+            return;
+
+        if (!int.TryParse(rawPort, out var port))
+        {
+            logger.WriteError("Failed parsing ROBUST_BENCHMARKS_SQL_PORT to int.");
+            return;
+        }
+
+        var builder = new DbContextOptionsBuilder<BenchmarkContext>();
+        var connectionString = new NpgsqlConnectionStringBuilder
+        {
+            Host = address,
+            Port = port,
+            Database = db,
+            Username = user,
+            Password = password
+        }.ConnectionString;
+        builder.UseNpgsql(connectionString);
+        using var ctx = new BenchmarkContext(builder.Options);
+        try
+        {
+            ctx.Database.Migrate();
+            ctx.BenchmarkRuns.Add(BenchmarkRun.FromSummary(summary, gitHash));
+            ctx.SaveChanges();
+        }
+        finally
+        {
+            ctx.Dispose();
+        }
+    }
+
+    public string Name => "sql";
+}
+
+public sealed class DesignTimeContextFactoryPostgres : IDesignTimeDbContextFactory<BenchmarkContext>
+{
+    public BenchmarkContext CreateDbContext(string[] args)
+    {
+        var optionsBuilder = new DbContextOptionsBuilder<BenchmarkContext>();
+        optionsBuilder.UseNpgsql("Server=localhost");
+        return new BenchmarkContext(optionsBuilder.Options);
+    }
+}
+
+public class BenchmarkContext : DbContext
+{
+    public DbSet<BenchmarkRun> BenchmarkRuns { get; set; } = default!;
+
+    public BenchmarkContext() { }
+    public BenchmarkContext(DbContextOptions<BenchmarkContext> options) : base(options) { }
+}
+
+public class BenchmarkRun
+{
+    [Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
+    public ulong Id { get; set; }
+    public string GitHash { get; set; } = string.Empty;
+    [Column(TypeName = "timestamptz")]
+    public DateTime RunDate { get; set; }
+    public string Name { get; set; } = string.Empty;
+    [Column(TypeName = "jsonb")]
+    public BenchmarkRunReport[] Reports { get; set; } = Array.Empty<BenchmarkRunReport>();
+
+    public static BenchmarkRun FromSummary(Summary summary, string gitHash)
+    {
+        return new BenchmarkRun
+        {
+            Reports = summary.Reports.Select(r => new BenchmarkRunReport
+            {
+                Parameters = r.BenchmarkCase.Parameters.Items.Select(p => new BenchmarkRunParameter
+                {
+                    Name = p.Name,
+                    Value = p.Value
+                }).ToArray(),
+                Statistics = r.ResultStatistics
+            }).ToArray(),
+            Name = summary.BenchmarksCases.First().FolderInfo,
+            RunDate = DateTime.UtcNow,
+            GitHash = gitHash
+        };
+    }
+}
+
+public class BenchmarkRunReport
+{
+    public BenchmarkRunParameter[] Parameters { get; set; } = Array.Empty<BenchmarkRunParameter>();
+    public Statistics Statistics { get; set; } = default!;
+}
+
+public class BenchmarkRunParameter
+{
+    public string Name { get; set; } = string.Empty;
+    public object Value { get; set; } = default!;
+}

Robust.Benchmarks/Migrations/20220328231938_InitialCreate.Designer.cs

@@ -0,0 +1,55 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    [DbContext(typeof(BenchmarkContext))]
+    [Migration("20220328231938_InitialCreate")]
+    partial class InitialCreate
+    {
+        protected override void BuildTargetModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "6.0.0")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Robust.Benchmarks.Exporters.BenchmarkRun", b =>
+                {
+                    b.Property<decimal>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("numeric(20,0)");
+
+                    b.Property<string>("GitHash")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<BenchmarkRunReport[]>("Reports")
+                        .IsRequired()
+                        .HasColumnType("jsonb");
+
+                    b.Property<DateTime>("RunDate")
+                        .HasColumnType("Date");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("BenchmarkRuns");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Robust.Benchmarks/Migrations/20220328231938_InitialCreate.cs

@@ -0,0 +1,35 @@
+using System;
+using Microsoft.EntityFrameworkCore.Migrations;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    public partial class InitialCreate : Migration
+    {
+        protected override void Up(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.CreateTable(
+                name: "BenchmarkRuns",
+                columns: table => new
+                {
+                    Id = table.Column<decimal>(type: "numeric(20,0)", nullable: false),
+                    GitHash = table.Column<string>(type: "text", nullable: false),
+                    RunDate = table.Column<DateTime>(type: "Date", nullable: false),
+                    Name = table.Column<string>(type: "text", nullable: false),
+                    Reports = table.Column<BenchmarkRunReport[]>(type: "jsonb", nullable: false)
+                },
+                constraints: table =>
+                {
+                    table.PrimaryKey("PK_BenchmarkRuns", x => x.Id);
+                });
+        }
+
+        protected override void Down(MigrationBuilder migrationBuilder)
+        {
+            migrationBuilder.DropTable(
+                name: "BenchmarkRuns");
+        }
+    }
+}

Robust.Benchmarks/Migrations/BenchmarkContextModelSnapshot.cs

@@ -0,0 +1,53 @@
+// <auto-generated />
+using System;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.EntityFrameworkCore.Infrastructure;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using Npgsql.EntityFrameworkCore.PostgreSQL.Metadata;
+using Robust.Benchmarks.Exporters;
+
+#nullable disable
+
+namespace Robust.Benchmarks.Migrations
+{
+    [DbContext(typeof(BenchmarkContext))]
+    partial class BenchmarkContextModelSnapshot : ModelSnapshot
+    {
+        protected override void BuildModel(ModelBuilder modelBuilder)
+        {
+#pragma warning disable 612, 618
+            modelBuilder
+                .HasAnnotation("ProductVersion", "6.0.0")
+                .HasAnnotation("Relational:MaxIdentifierLength", 63);
+
+            NpgsqlModelBuilderExtensions.UseIdentityByDefaultColumns(modelBuilder);
+
+            modelBuilder.Entity("Robust.Benchmarks.Exporters.BenchmarkRun", b =>
+                {
+                    b.Property<decimal>("Id")
+                        .ValueGeneratedOnAdd()
+                        .HasColumnType("numeric(20,0)");
+
+                    b.Property<string>("GitHash")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<string>("Name")
+                        .IsRequired()
+                        .HasColumnType("text");
+
+                    b.Property<BenchmarkRunReport[]>("Reports")
+                        .IsRequired()
+                        .HasColumnType("jsonb");
+
+                    b.Property<DateTime>("RunDate")
+                        .HasColumnType("Date");
+
+                    b.HasKey("Id");
+
+                    b.ToTable("BenchmarkRuns");
+                });
+#pragma warning restore 612, 618
+        }
+    }
+}

Robust.Benchmarks/NumericsHelpers/AddBenchmark.cs

@@ -1,12 +1,17 @@
 using BenchmarkDotNet.Attributes;
+using Robust.Shared.Analyzers;
 
 namespace Robust.Benchmarks.NumericsHelpers
 {
+    [Virtual]
     public class AddBenchmark
     {
         [Params(32, 128)]
         public int N { get; set; }
 
+        [Params(1,2)]
+        public int T { get; set; }
+
         private float[] _inputA = default!;
         private float[] _inputB = default!;
         private float[] _output = default!;

Robust.Benchmarks/Program.cs

@@ -1,10 +1,12 @@
 using BenchmarkDotNet.Configs;
 using BenchmarkDotNet.Running;
 using System;
+using Robust.Benchmarks.Configs;
+using Robust.Benchmarks.Exporters;
 
 namespace Robust.Benchmarks
 {
-    internal class Program
+    internal static class Program
     {
         // --allCategories=ctg1,ctg2
         // --anyCategories=ctg1,ctg2
@@ -16,7 +18,8 @@ namespace Robust.Benchmarks
             Console.WriteLine("THE DEBUG BUILD IS ONLY GOOD FOR FIXING A CRASHING BENCHMARK\n");
             BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args, new DebugInProcessConfig());
 #else
-            BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args);
+            var config = Environment.GetEnvironmentVariable("ROBUST_BENCHMARKS_ENABLE_SQL") != null ? DefaultSQLConfig.Instance : null;
+            BenchmarkSwitcher.FromAssembly(typeof(Program).Assembly).Run(args, config);
 #endif
         }
     }

Robust.Benchmarks/Robust.Benchmarks.csproj

@@ -10,9 +10,15 @@
     <ItemGroup>
       <ProjectReference Include="..\Robust.Server\Robust.Server.csproj" />
       <ProjectReference Include="..\Robust.Shared\Robust.Shared.csproj" />
+      <ProjectReference Include="..\Robust.UnitTesting\Robust.UnitTesting.csproj" />
     </ItemGroup>
     <ItemGroup>
       <PackageReference Include="BenchmarkDotNet" Version="0.12.1" />
+      <PackageReference Include="Microsoft.EntityFrameworkCore.Design" Version="6.0.0">
+        <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+        <PrivateAssets>all</PrivateAssets>
+      </PackageReference>
+      <PackageReference Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="6.0.0-rc.2" />
     </ItemGroup>
     <Import Project="..\MSBuild\Robust.Engine.targets" />
 </Project>

Robust.Benchmarks/Serialization/BenchmarkIntSerializer.cs

@@ -9,7 +9,7 @@ using Robust.Shared.Serialization.TypeSerializers.Interfaces;
 
 namespace Robust.Benchmarks.Serialization
 {
-    public class BenchmarkIntSerializer : ITypeSerializer<int, ValueDataNode>
+    public sealed class BenchmarkIntSerializer : ITypeSerializer<int, ValueDataNode>
     {
         public ValidationNode Validate(ISerializationManager serializationManager, ValueDataNode node,
             IDependencyCollection dependencies, ISerializationContext? context = null)

Robust.Benchmarks/Serialization/Copy/SerializationCopyBenchmark.cs

@@ -2,6 +2,7 @@
 using System.Linq;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
@@ -13,6 +14,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Copy
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationCopyBenchmark : SerializationBenchmark
     {
         public SerializationCopyBenchmark()

Robust.Benchmarks/Serialization/Definitions/BenchmarkFlags.cs

@@ -3,7 +3,7 @@ using Robust.Shared.Serialization;
 
 namespace Robust.Benchmarks.Serialization.Definitions
 {
-    public class BenchmarkFlags
+    public sealed class BenchmarkFlags
     {
         public const int Zero = 1 << 0;
         public const int ThirtyOne = 1 << 31;

Robust.Benchmarks/Serialization/Definitions/DataDefinitionWithString.cs

@@ -1,8 +1,10 @@
-using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Analyzers;
+using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Robust.Benchmarks.Serialization.Definitions
 {
     [DataDefinition]
+    [Virtual]
     public class DataDefinitionWithString
     {
         [DataField("string")]

Robust.Benchmarks/Serialization/Definitions/SeedDataDefinition.cs

@@ -11,7 +11,7 @@ namespace Robust.Benchmarks.Serialization.Definitions
     ///     Taken from content.
     /// </summary>
     [Prototype("seed")]
-    public class SeedDataDefinition : IPrototype
+    public sealed class SeedDataDefinition : IPrototype
     {
         public const string Prototype = @"
 - type: seed

Robust.Benchmarks/Serialization/Initialize/SerializationInitializeBenchmark.cs

@@ -1,9 +1,11 @@
 using BenchmarkDotNet.Attributes;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 
 namespace Robust.Benchmarks.Serialization.Initialize
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationInitializeBenchmark : SerializationBenchmark
     {
         [IterationCleanup]

Robust.Benchmarks/Serialization/Read/SerializationReadBenchmark.cs

@@ -1,6 +1,7 @@
 using System.IO;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager.Result;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
@@ -12,6 +13,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Read
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationReadBenchmark : SerializationBenchmark
     {
         public SerializationReadBenchmark()

Robust.Benchmarks/Serialization/SerializationArrayBenchmark.cs

@@ -1,5 +1,6 @@
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Markdown.Mapping;
 using Robust.Shared.Serialization.Markdown.Sequence;
 using Robust.Shared.Serialization.Markdown.Value;
@@ -7,6 +8,7 @@ using Robust.Shared.Serialization.Markdown.Value;
 namespace Robust.Benchmarks.Serialization
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationArrayBenchmark : SerializationBenchmark
     {
         public SerializationArrayBenchmark()

Robust.Benchmarks/Serialization/Write/SerializationWriteBenchmark.cs

@@ -2,6 +2,7 @@
 using System.IO;
 using BenchmarkDotNet.Attributes;
 using Robust.Benchmarks.Serialization.Definitions;
+using Robust.Shared.Analyzers;
 using Robust.Shared.Serialization.Manager;
 using Robust.Shared.Serialization.Markdown;
 using Robust.Shared.Serialization.Markdown.Mapping;
@@ -13,6 +14,7 @@ using YamlDotNet.RepresentationModel;
 namespace Robust.Benchmarks.Serialization.Write
 {
     [MemoryDiagnoser]
+    [Virtual]
     public class SerializationWriteBenchmark : SerializationBenchmark
     {
         public SerializationWriteBenchmark()

Robust.Benchmarks/add-migration.ps1

@@ -0,0 +1,11 @@
+#!/usr/bin/env pwsh
+
+param([String]$name)
+
+if ($name -eq "")
+{
+    Write-Error "must specify migration name"
+    exit
+}
+
+dotnet ef migrations add --context BenchmarkContext -o Migrations $name

Robust.Benchmarks/add-migration.sh

@@ -0,0 +1,8 @@
+#!/usr/bin/env bash
+
+if [ -z "$1" ] ; then
+    echo "Must specify migration name"
+    exit 1
+fi
+
+dotnet ef migrations add --context BenchmarkContext -o Migrations "$1"

Robust.Client.Injectors/Robust.Client.Injectors.csproj

@@ -6,7 +6,7 @@
     </PropertyGroup>
 
     <ItemGroup>
-      <PackageReference Include="Microsoft.Build.Framework" Version="16.8.0" />
+      <PackageReference Include="Microsoft.Build.Framework" Version="17.0.0" />
       <PackageReference Include="Mono.Cecil" Version="0.11.3" />
       <PackageReference Include="Pidgin" Version="2.5.0" />
     </ItemGroup>

Robust.Client.NameGenerator/Robust.Client.NameGenerator.csproj

@@ -5,8 +5,8 @@
     </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="3.8.0" PrivateAssets="all" />
-    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.2" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.CSharp" Version="4.0.1" PrivateAssets="all" />
+    <PackageReference Include="Microsoft.CodeAnalysis.Analyzers" Version="3.3.3" PrivateAssets="all" />
   </ItemGroup>
 
   <ItemGroup>

Robust.Client/Animations/AnimationTrackControlProperty.cs

@@ -3,7 +3,7 @@ using Robust.Shared.Animations;
 
 namespace Robust.Client.Animations
 {
-    public class AnimationTrackControlProperty : AnimationTrackProperty
+    public sealed class AnimationTrackControlProperty : AnimationTrackProperty
     {
         public string? Property { get; set; }
 

Robust.Client/Audio/Midi/MidiManager.cs

@@ -58,7 +58,7 @@ namespace Robust.Client.Audio.Midi
         void Shutdown();
     }
 
-    internal class MidiManager : IMidiManager
+    internal sealed class MidiManager : IMidiManager
     {
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly IResourceManagerInternal _resourceManager = default!;
@@ -392,7 +392,7 @@ namespace Robust.Client.Audio.Midi
         /// <summary>
         ///     This class is used to load soundfonts.
         /// </summary>
-        private class ResourceLoaderCallbacks : SoundFontLoaderCallbacks
+        private sealed class ResourceLoaderCallbacks : SoundFontLoaderCallbacks
         {
             private readonly Dictionary<int, Stream> _openStreams = new();
             private int _nextStreamId = 1;

Robust.Client/Audio/Midi/MidiRenderer.cs

@@ -180,7 +180,7 @@ namespace Robust.Client.Audio.Midi
         internal void InternalDispose();
     }
 
-    internal class MidiRenderer : IMidiRenderer
+    internal sealed class MidiRenderer : IMidiRenderer
     {
         [Dependency] private readonly IClydeAudio _clydeAudio = default!;
         [Dependency] private readonly ITaskManager _taskManager = default!;
@@ -619,6 +619,7 @@ namespace Robust.Client.Audio.Midi
             var seqEv = (SequencerEvent) midiEvent;
             seqEv.Dest = _debugEvents ? _debugRegister : _synthRegister;
             _sequencer.SendAt(seqEv, time, absolute);
+            seqEv.Dispose();
         }
 
         public void Dispose()

Robust.Client/BaseClient.cs

@@ -20,13 +20,12 @@ using Robust.Shared.Utility;
 namespace Robust.Client
 {
     /// <inheritdoc />
-    public class BaseClient : IBaseClient
+    public sealed class BaseClient : IBaseClient
     {
         [Dependency] private readonly IClientNetManager _net = default!;
         [Dependency] private readonly IPlayerManager _playMan = default!;
         [Dependency] private readonly INetConfigurationManager _configManager = default!;
         [Dependency] private readonly IClientEntityManager _entityManager = default!;
-        [Dependency] private readonly IEntityLookup _entityLookup = default!;
         [Dependency] private readonly IMapManager _mapManager = default!;
         [Dependency] private readonly IDiscordRichPresence _discord = default!;
         [Dependency] private readonly IGameTiming _timing = default!;
@@ -213,7 +212,6 @@ namespace Robust.Client
         {
             _entityManager.Startup();
             _mapManager.Startup();
-            _entityLookup.Startup();
 
             _timing.ResetSimTime();
             _timing.Paused = false;
@@ -224,7 +222,6 @@ namespace Robust.Client
             IoCManager.Resolve<INetConfigurationManager>().FlushMessages();
             _gameStates.Reset();
             _playMan.Shutdown();
-            _entityLookup.Shutdown();
             _entityManager.Shutdown();
             _mapManager.Shutdown();
             _discord.ClearPresence();
@@ -291,7 +288,7 @@ namespace Robust.Client
     /// <summary>
     ///     Event arguments for when something changed with the player.
     /// </summary>
-    public class PlayerEventArgs : EventArgs
+    public sealed class PlayerEventArgs : EventArgs
     {
         /// <summary>
         ///     The session that triggered the event.
@@ -310,7 +307,7 @@ namespace Robust.Client
     /// <summary>
     ///     Event arguments for when the RunLevel has changed in the BaseClient.
     /// </summary>
-    public class RunLevelChangedEventArgs : EventArgs
+    public sealed class RunLevelChangedEventArgs : EventArgs
     {
         /// <summary>
         ///     RunLevel that the BaseClient switched from.
@@ -335,7 +332,7 @@ namespace Robust.Client
     /// <summary>
     ///     Info about the server and player that is sent to the client while connecting.
     /// </summary>
-    public class ServerInfo
+    public sealed class ServerInfo
     {
         public ServerInfo(string serverName)
         {

Robust.Client/ClientIoC.cs

@@ -43,11 +43,10 @@ namespace Robust.Client
             IoCManager.Register<IGameTiming, ClientGameTiming>();
             IoCManager.Register<IClientGameTiming, ClientGameTiming>();
             IoCManager.Register<IPrototypeManager, ClientPrototypeManager>();
-            IoCManager.Register<IMapManager, ClientMapManager>();
-            IoCManager.Register<IMapManagerInternal, ClientMapManager>();
-            IoCManager.Register<IClientMapManager, ClientMapManager>();
+            IoCManager.Register<IMapManager, NetworkedMapManager>();
+            IoCManager.Register<IMapManagerInternal, NetworkedMapManager>();
+            IoCManager.Register<INetworkedMapManager, NetworkedMapManager>();
             IoCManager.Register<IEntityManager, ClientEntityManager>();
-            IoCManager.Register<IEntityLookup, EntityLookup>();
             IoCManager.Register<IReflectionManager, ClientReflectionManager>();
             IoCManager.Register<IConsoleHost, ClientConsoleHost>();
             IoCManager.Register<IClientConsoleHost, ClientConsoleHost>();
@@ -72,7 +71,6 @@ namespace Robust.Client
             IoCManager.Register<IStateManager, StateManager>();
             IoCManager.Register<IUserInterfaceManager, UserInterfaceManager>();
             IoCManager.Register<IUserInterfaceManagerInternal, UserInterfaceManager>();
-            IoCManager.Register<IDebugDrawing, DebugDrawing>();
             IoCManager.Register<ILightManager, LightManager>();
             IoCManager.Register<IDiscordRichPresence, DiscordRichPresence>();
             IoCManager.Register<IMidiManager, MidiManager>();

Robust.Client/Console/ClientConGroupController.cs

@@ -2,7 +2,7 @@
 
 namespace Robust.Client.Console
 {
-    public class ClientConGroupController : IClientConGroupController
+    public sealed class ClientConGroupController : IClientConGroupController
     {
         private IClientConGroupImplementation? _implementation;
         public event Action? ConGroupUpdated;

Robust.Client/Console/ClientConsoleHost.cs

@@ -14,7 +14,7 @@ using Robust.Shared.Utility;
 
 namespace Robust.Client.Console
 {
-    public class AddStringArgs : EventArgs
+    public sealed class AddStringArgs : EventArgs
     {
         public string Text { get; }
 
@@ -30,7 +30,7 @@ namespace Robust.Client.Console
         }
     }
 
-    public class AddFormattedMessageArgs : EventArgs
+    public sealed class AddFormattedMessageArgs : EventArgs
     {
         public readonly FormattedMessage Message;
 
@@ -41,7 +41,7 @@ namespace Robust.Client.Console
     }
 
     /// <inheritdoc cref="IClientConsoleHost" />
-    internal class ClientConsoleHost : ConsoleHost, IClientConsoleHost
+    internal sealed class ClientConsoleHost : ConsoleHost, IClientConsoleHost
     {
         [Dependency] private readonly IClientConGroupController _conGroup = default!;
 
@@ -109,13 +109,13 @@ namespace Robust.Client.Console
             if (AvailableCommands.ContainsKey(commandName))
             {
                 var playerManager = IoCManager.Resolve<IPlayerManager>();
-
+#if !DEBUG
                 if (!_conGroup.CanCommand(commandName) && playerManager.LocalPlayer?.Session.Status > SessionStatus.Connecting)
                 {
                     WriteError(null, $"Insufficient perms for command: {commandName}");
                     return;
                 }
-
+#endif
                 var command1 = AvailableCommands[commandName];
                 args.RemoveAt(0);
                 var shell = new ConsoleShell(this, null);
@@ -209,7 +209,7 @@ namespace Robust.Client.Console
     /// These dummies are made purely so list and help can list server-side commands.
     /// </summary>
     [Reflect(false)]
-    internal class ServerDummyCommand : IConsoleCommand
+    internal sealed class ServerDummyCommand : IConsoleCommand
     {
         internal ServerDummyCommand(string command, string help, string description)
         {

Robust.Client/Console/Commands/ConfigurationCommands.cs

@@ -59,7 +59,7 @@ namespace Robust.Client.Console.Commands
     }
 
     [UsedImplicitly]
-    public class SaveConfig : IConsoleCommand
+    public sealed class SaveConfig : IConsoleCommand
     {
         public string Command => "saveconfig";
         public string Description => "Saves the client configuration to the config file";

Robust.Client/Console/Commands/ConsoleCommands.cs

@@ -6,7 +6,7 @@ using Robust.Shared.Console;
 
 namespace Robust.Client.Console.Commands
 {
-    class ClearCommand : IConsoleCommand
+    sealed class ClearCommand : IConsoleCommand
     {
         public string Command => "cls";
         public string Help => "Clears the debug console of all messages.";
@@ -18,7 +18,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    class FillCommand : IConsoleCommand
+    sealed class FillCommand : IConsoleCommand
     {
         public string Command => "fill";
         public string Help => "Fills the console with some nonsense for debugging.";

Robust.Client/Console/Commands/Debug.cs

@@ -30,7 +30,7 @@ using static Robust.Client.UserInterface.Controls.BoxContainer;
 
 namespace Robust.Client.Console.Commands
 {
-    internal class DumpEntitiesCommand : IConsoleCommand
+    internal sealed class DumpEntitiesCommand : IConsoleCommand
     {
         public string Command => "dumpentities";
         public string Help => "Dump entity list";
@@ -47,7 +47,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GetComponentRegistrationCommand : IConsoleCommand
+    internal sealed class GetComponentRegistrationCommand : IConsoleCommand
     {
         public string Command => "getcomponentregistration";
         public string Help => "Usage: getcomponentregistration <componentName>";
@@ -93,7 +93,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ToggleMonitorCommand : IConsoleCommand
+    internal sealed class ToggleMonitorCommand : IConsoleCommand
     {
         public string Command => "monitor";
 
@@ -148,7 +148,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ExceptionCommand : IConsoleCommand
+    internal sealed class ExceptionCommand : IConsoleCommand
     {
         public string Command => "fuck";
         public string Help => "Throws an exception";
@@ -160,7 +160,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ShowPositionsCommand : IConsoleCommand
+    internal sealed class ShowPositionsCommand : IConsoleCommand
     {
         public string Command => "showpos";
         public string Help => "";
@@ -168,12 +168,12 @@ namespace Robust.Client.Console.Commands
 
         public void Execute(IConsoleShell shell, string argStr, string[] args)
         {
-            var mgr = IoCManager.Resolve<IDebugDrawing>();
+            var mgr = EntitySystem.Get<DebugDrawingSystem>();
             mgr.DebugPositions = !mgr.DebugPositions;
         }
     }
 
-    internal class ShowRayCommand : IConsoleCommand
+    internal sealed class ShowRayCommand : IConsoleCommand
     {
         public string Command => "showrays";
         public string Help => "Usage: showrays <raylifetime>";
@@ -200,7 +200,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class DisconnectCommand : IConsoleCommand
+    internal sealed class DisconnectCommand : IConsoleCommand
     {
         public string Command => "disconnect";
         public string Help => "";
@@ -212,7 +212,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class EntityInfoCommand : IConsoleCommand
+    internal sealed class EntityInfoCommand : IConsoleCommand
     {
         public string Command => "entfo";
 
@@ -264,7 +264,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class SnapGridGetCell : IConsoleCommand
+    internal sealed class SnapGridGetCell : IConsoleCommand
     {
         public string Command => "sggcell";
         public string Help => "sggcell <gridID> <vector2i>\nThat vector2i param is in the form x<int>,y<int>.";
@@ -313,7 +313,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class SetPlayerName : IConsoleCommand
+    internal sealed class SetPlayerName : IConsoleCommand
     {
         public string Command => "overrideplayername";
         public string Description => "Changes the name used when attempting to connect to the server.";
@@ -333,7 +333,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class LoadResource : IConsoleCommand
+    internal sealed class LoadResource : IConsoleCommand
     {
         public string Command => "ldrsc";
         public string Description => "Pre-caches a resource.";
@@ -370,7 +370,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ReloadResource : IConsoleCommand
+    internal sealed class ReloadResource : IConsoleCommand
     {
         public string Command => "rldrsc";
         public string Description => "Reloads a resource.";
@@ -404,7 +404,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GridTileCount : IConsoleCommand
+    internal sealed class GridTileCount : IConsoleCommand
     {
         public string Command => "gridtc";
         public string Description => "Gets the tile count of a grid";
@@ -438,7 +438,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GuiDumpCommand : IConsoleCommand
+    internal sealed class GuiDumpCommand : IConsoleCommand
     {
         public string Command => "guidump";
         public string Description => "Dump GUI tree to /guidump.txt in user data.";
@@ -512,7 +512,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class UITestCommand : IConsoleCommand
+    internal sealed class UITestCommand : IConsoleCommand
     {
         public string Command => "uitest";
         public string Description => "Open a dummy UI testing window";
@@ -644,7 +644,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class SetClipboardCommand : IConsoleCommand
+    internal sealed class SetClipboardCommand : IConsoleCommand
     {
         public string Command => "setclipboard";
         public string Description => "Sets the system clipboard";
@@ -657,7 +657,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GetClipboardCommand : IConsoleCommand
+    internal sealed class GetClipboardCommand : IConsoleCommand
     {
         public string Command => "getclipboard";
         public string Description => "Gets the system clipboard";
@@ -670,7 +670,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ToggleLight : IConsoleCommand
+    internal sealed class ToggleLight : IConsoleCommand
     {
         public string Command => "togglelight";
         public string Description => "Toggles light rendering.";
@@ -684,7 +684,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ToggleFOV : IConsoleCommand
+    internal sealed class ToggleFOV : IConsoleCommand
     {
         public string Command => "togglefov";
         public string Description => "Toggles fov for client.";
@@ -698,7 +698,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ToggleHardFOV : IConsoleCommand
+    internal sealed class ToggleHardFOV : IConsoleCommand
     {
         public string Command => "togglehardfov";
         public string Description => "Toggles hard fov for client (for debugging space-station-14#2353).";
@@ -712,7 +712,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class ToggleShadows : IConsoleCommand
+    internal sealed class ToggleShadows : IConsoleCommand
     {
         public string Command => "toggleshadows";
         public string Description => "Toggles shadow rendering.";
@@ -725,7 +725,7 @@ namespace Robust.Client.Console.Commands
                 mgr.DrawShadows = !mgr.DrawShadows;
         }
     }
-    internal class ToggleLightBuf : IConsoleCommand
+    internal sealed class ToggleLightBuf : IConsoleCommand
     {
         public string Command => "togglelightbuf";
         public string Description => "Toggles lighting rendering. This includes shadows but not FOV.";
@@ -739,7 +739,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GcCommand : IConsoleCommand
+    internal sealed class GcCommand : IConsoleCommand
     {
         public string Command => "gc";
         public string Description => "Run the GC.";
@@ -761,7 +761,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GcFullCommand : IConsoleCommand
+    internal sealed class GcFullCommand : IConsoleCommand
     {
         public string Command => "gcf";
         public string Description => "Run the GC, fully, compacting LOH and everything.";
@@ -774,7 +774,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GcModeCommand : IConsoleCommand
+    internal sealed class GcModeCommand : IConsoleCommand
     {
 
         public string Command => "gc_mode";
@@ -816,7 +816,7 @@ namespace Robust.Client.Console.Commands
 
     }
 
-    internal class SerializeStatsCommand : IConsoleCommand
+    internal sealed class SerializeStatsCommand : IConsoleCommand
     {
 
         public string Command => "szr_stats";
@@ -836,7 +836,7 @@ namespace Robust.Client.Console.Commands
 
     }
 
-    internal class ChunkInfoCommand : IConsoleCommand
+    internal sealed class ChunkInfoCommand : IConsoleCommand
     {
         public string Command => "chunkinfo";
         public string Description => "Gets info about a chunk under your mouse cursor.";
@@ -861,11 +861,11 @@ namespace Robust.Client.Console.Commands
             var chunkIndex = grid.LocalToChunkIndices(grid.MapToGrid(mousePos));
             var chunk = internalGrid.GetChunk(chunkIndex);
 
-            shell.WriteLine($"worldBounds: {chunk.CalcWorldAABB()} localBounds: {chunk.CalcLocalBounds()}");
+            shell.WriteLine($"worldBounds: {internalGrid.CalcWorldAABB(chunk)} localBounds: {chunk.CachedBounds}");
         }
     }
 
-    internal class ReloadShadersCommand : IConsoleCommand
+    internal sealed class ReloadShadersCommand : IConsoleCommand
     {
 
         public string Command => "rldshader";
@@ -1036,7 +1036,7 @@ namespace Robust.Client.Console.Commands
 
     }
 
-    internal class ClydeDebugLayerCommand : IConsoleCommand
+    internal sealed class ClydeDebugLayerCommand : IConsoleCommand
     {
         public string Command => "cldbglyr";
         public string Description => "Toggle fov and light debug layers";
@@ -1061,7 +1061,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    internal class GetKeyInfoCommand : IConsoleCommand
+    internal sealed class GetKeyInfoCommand : IConsoleCommand
     {
         public string Command => "keyinfo";
         public string Description => "Keys key info for a key";

Robust.Client/Console/Commands/GridChunkBBCommand.cs

@@ -4,7 +4,7 @@ using Robust.Shared.GameObjects;
 
 namespace Robust.Client.Console.Commands
 {
-    public class GridChunkBBCommand : IConsoleCommand
+    public sealed class GridChunkBBCommand : IConsoleCommand
     {
         public string Command => "showchunkbb";
         public string Description => "Displays chunk bounds for the purposes of rendering";

Robust.Client/Console/Commands/HelpCommands.cs

@@ -5,7 +5,7 @@ using Robust.Shared.Network;
 
 namespace Robust.Client.Console.Commands
 {
-    class HelpCommand : IConsoleCommand
+    sealed class HelpCommand : IConsoleCommand
     {
         public string Command => "help";
         public string Help => "When no arguments are provided, displays a generic help text. When an argument is passed, display the help text for the command with that name.";
@@ -44,7 +44,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    class ListCommand : IConsoleCommand
+    sealed class ListCommand : IConsoleCommand
     {
         public string Command => "list";
         public string Help => "Usage: list [filter]\n" +

Robust.Client/Console/Commands/LogCommands.cs

@@ -4,7 +4,7 @@ using Robust.Shared.Console;
 
 namespace Robust.Client.Console.Commands
 {
-    class LogSetLevelCommand : IConsoleCommand
+    sealed class LogSetLevelCommand : IConsoleCommand
     {
         public string Command => "loglevel";
         public string Description => "Changes the log level for a provided sawmill.";
@@ -40,7 +40,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    class TestLog : IConsoleCommand
+    sealed class TestLog : IConsoleCommand
     {
         public string Command => "testlog";
         public string Description => "Writes a test log to a sawmill.";

Robust.Client/Console/Commands/QuitCommand.cs

@@ -4,7 +4,7 @@ using Robust.Shared.IoC;
 
 namespace Robust.Client.Console.Commands
 {
-    class HardQuitCommand : IConsoleCommand
+    sealed class HardQuitCommand : IConsoleCommand
     {
         public string Command => "hardquit";
         public string Description => "Kills the game client instantly.";
@@ -16,7 +16,7 @@ namespace Robust.Client.Console.Commands
         }
     }
 
-    class QuitCommand : IConsoleCommand
+    sealed class QuitCommand : IConsoleCommand
     {
         public string Command => "quit";
         public string Description => "Shuts down the game client gracefully.";

Robust.Client/Console/Commands/SetInputContextCommand.cs

@@ -6,7 +6,7 @@ using Robust.Shared.IoC;
 namespace Robust.Client.Console.Commands
 {
     [UsedImplicitly]
-    public class SetInputContextCommand : IConsoleCommand
+    public sealed class SetInputContextCommand : IConsoleCommand
     {
         public string Command => "setinputcontext";
         public string Description => "Sets the active input context.";

Robust.Client/Console/Commands/VelocitiesCommand.cs

@@ -4,7 +4,7 @@ using Robust.Shared.GameObjects;
 
 namespace Robust.Client.Console.Commands
 {
-    public class VelocitiesCommand : IConsoleCommand
+    public sealed class VelocitiesCommand : IConsoleCommand
     {
         public string Command => "showvelocities";
         public string Description => "Displays your angular and linear velocities";

Robust.Client/Console/Completions.cs

@@ -11,7 +11,7 @@ using static Robust.Shared.Network.Messages.MsgScriptCompletionResponse;
 
 namespace Robust.Client.Console
 {
-    public class Completions : DefaultWindow
+    public sealed class Completions : DefaultWindow
     {
         private HistoryLineEdit _textBar;
         private ScrollContainer _suggestPanel = new()
@@ -75,7 +75,7 @@ namespace Robust.Client.Console
         }
 
         // Label and ghetto button.
-        public class Entry : RichTextLabel
+        public sealed class Entry : RichTextLabel
         {
             public readonly LiteResult Result;
 

Robust.Client/Console/ScriptClient.cs

@@ -6,7 +6,7 @@ using Robust.Shared.Network.Messages;
 
 namespace Robust.Client.Console
 {
-    public partial class ScriptClient : IScriptClient
+    public sealed partial class ScriptClient : IScriptClient
     {
         [Dependency] private readonly IClientConGroupController _conGroupController = default!;
         [Dependency] private readonly IClientNetManager _netManager = default!;

Robust.Client/Console/WatchWindow.cs

@@ -15,7 +15,7 @@ using static Robust.Client.UserInterface.Controls.BoxContainer;
 
 namespace Robust.Client.Console
 {
-    public class WatchWindow : DefaultWindow
+    public sealed class WatchWindow : DefaultWindow
     {
         private readonly IReflectionManager _reflectionManager;
 

Robust.Client/Debugging/DebugDrawingSystem.cs

@@ -6,17 +6,21 @@ using Robust.Shared.Maths;
 
 namespace Robust.Client.Debugging
 {
-    /// <inheritdoc />
-    public class DebugDrawing : IDebugDrawing
+    /// <summary>
+    /// A collection of visual debug overlays for the client game.
+    /// </summary>
+    public sealed class DebugDrawingSystem : EntitySystem
     {
         [Dependency] private readonly IOverlayManager _overlayManager = default!;
         [Dependency] private readonly IEyeManager _eyeManager = default!;
-        [Dependency] private readonly IEntityLookup _lookup = default!;
         [Dependency] private readonly IEntityManager _entityManager = default!;
+        [Dependency] private readonly EntityLookupSystem _lookup = default!;
 
         private bool _debugPositions;
 
-        /// <inheritdoc />
+        /// <summary>
+        /// Toggles the visual overlay of the local origin for each entity on screen.
+        /// </summary>
         public bool DebugPositions
         {
             get => _debugPositions;
@@ -42,13 +46,13 @@ namespace Robust.Client.Debugging
 
         private sealed class EntityPositionOverlay : Overlay
         {
-            private readonly IEntityLookup _lookup;
+            private readonly EntityLookupSystem _lookup;
             private readonly IEyeManager _eyeManager;
             private readonly IEntityManager _entityManager;
 
             public override OverlaySpace Space => OverlaySpace.WorldSpace;
 
-            public EntityPositionOverlay(IEntityLookup lookup, IEyeManager eyeManager, IEntityManager entityManager)
+            public EntityPositionOverlay(EntityLookupSystem lookup, IEyeManager eyeManager, IEntityManager entityManager)
             {
                 _lookup = lookup;
                 _eyeManager = eyeManager;
@@ -61,13 +65,11 @@ namespace Robust.Client.Debugging
 
                 var worldHandle = (DrawingHandleWorld) args.DrawingHandle;
                 var viewport = _eyeManager.GetWorldViewport();
+                var xformQuery = _entityManager.GetEntityQuery<TransformComponent>();
 
                 foreach (var entity in _lookup.GetEntitiesIntersecting(_eyeManager.CurrentMap, viewport))
                 {
-                    var transform = _entityManager.GetComponent<TransformComponent>(entity);
-
-                    var center = transform.WorldPosition;
-                    var worldRotation = transform.WorldRotation;
+                    var (center, worldRotation) = xformQuery.GetComponent(entity).GetWorldPositionRotation();
 
                     var xLine = worldRotation.RotateVec(Vector2.UnitX);
                     var yLine = worldRotation.RotateVec(Vector2.UnitY);

Robust.Client/Debugging/DebugPhysicsSystem.cs

@@ -207,10 +207,10 @@ namespace Robust.Client.Debugging
 
                     const float AlphaModifier = 0.2f;
 
-                    foreach (var fixture in physBody.Fixtures)
+                    foreach (var fixture in _entityManager.GetComponent<FixturesComponent>(physBody.Owner).Fixtures.Values)
                     {
-                        // Invalid shape - Box2D doesn't check for IsSensor
-                        if (physBody.BodyType == BodyType.Dynamic && fixture.Mass == 0f)
+                        // Invalid shape - Box2D doesn't check for IsSensor but we will for sanity.
+                        if (physBody.BodyType == BodyType.Dynamic && fixture.Mass == 0f && fixture.Hard)
                         {
                             DrawShape(worldHandle, fixture, xform, Color.Red.WithAlpha(AlphaModifier));
                         }
@@ -274,7 +274,7 @@ namespace Robust.Client.Debugging
                     const float AlphaModifier = 0.2f;
                     Box2? aabb = null;
 
-                    foreach (var fixture in physBody.Fixtures)
+                    foreach (var fixture in _entityManager.GetComponent<FixturesComponent>(physBody.Owner).Fixtures.Values)
                     {
                         for (var i = 0; i < fixture.Shape.ChildCount; i++)
                         {

Robust.Client/Debugging/IDebugDrawing.cs

@@ -1,13 +0,0 @@
-namespace Robust.Client.Debugging
-{
-    /// <summary>
-    /// A collection of visual debug overlays for the client game.
-    /// </summary>
-    public interface IDebugDrawing
-    {
-        /// <summary>
-        /// Toggles the visual overlay of the local origin for each entity on screen.
-        /// </summary>
-        bool DebugPositions { get; set; }
-    }
-}

Robust.Client/GameController/GameController.Loader.cs

@@ -7,7 +7,7 @@ namespace Robust.Client
 {
     internal partial class GameController
     {
-        internal class LoaderEntryPoint : ILoaderEntryPoint
+        internal sealed class LoaderEntryPoint : ILoaderEntryPoint
         {
             public void Main(IMainArgs args)
             {

Robust.Client/GameController/GameController.cs

@@ -50,7 +50,6 @@ namespace Robust.Client
         [Dependency] private readonly IClientConsoleHost _console = default!;
         [Dependency] private readonly ITimerManager _timerManager = default!;
         [Dependency] private readonly IClientEntityManager _entityManager = default!;
-        [Dependency] private readonly IEntityLookup _lookup = default!;
         [Dependency] private readonly IPlacementManager _placementManager = default!;
         [Dependency] private readonly IClientGameStateManager _gameStateManager = default!;
         [Dependency] private readonly IOverlayManagerInternal _overlayManager = default!;
@@ -134,8 +133,8 @@ namespace Robust.Client
             _prototypeManager.Initialize();
             _prototypeManager.LoadDirectory(Options.PrototypeDirectory);
             _prototypeManager.Resync();
-            _mapManager.Initialize();
             _entityManager.Initialize();
+            _mapManager.Initialize();
             _gameStateManager.Initialize();
             _placementManager.Initialize();
             _viewVariablesManager.Initialize();
@@ -339,6 +338,14 @@ namespace Robust.Client
 
             if (_loaderArgs != null)
             {
+                if (_loaderArgs.ApiMounts is { } mounts)
+                {
+                    foreach (var (api, prefix) in mounts)
+                    {
+                        _resourceCache.MountLoaderApi(api, "", new ResourcePath(prefix));
+                    }
+                }
+
                 _stringSerializer.EnableCaching = false;
                 _resourceCache.MountLoaderApi(_loaderArgs.FileApi, "Resources/");
                 _modLoader.VerifierExtraLoadHandler = VerifierExtraLoadHandler;
@@ -447,6 +454,7 @@ namespace Robust.Client
         private void Tick(FrameEventArgs frameEventArgs)
         {
             _modLoader.BroadcastUpdate(ModUpdateLevel.PreEngine, frameEventArgs);
+            _console.CommandBufferExecute();
             _timerManager.UpdateTimers(frameEventArgs);
             _taskManager.ProcessPendingTasks();
 
@@ -459,8 +467,9 @@ namespace Robust.Client
             // In singleplayer, however, we're in full control instead.
             else if (_client.RunLevel == ClientRunLevel.SinglePlayerGame)
             {
+                // The last real tick is the current tick! This way we won't be in "prediction" mode.
+                _gameTiming.LastRealTick = _gameTiming.CurTick;
                 _entityManager.TickUpdate(frameEventArgs.DeltaSeconds, noPredictions: false);
-                _lookup.Update();
             }
 
             _modLoader.BroadcastUpdate(ModUpdateLevel.PostEngine, frameEventArgs);
@@ -500,7 +509,7 @@ namespace Robust.Client
             logManager.GetSawmill("discord").Level = LogLevel.Warning;
             logManager.GetSawmill("net.predict").Level = LogLevel.Info;
             logManager.GetSawmill("szr").Level = LogLevel.Info;
-            logManager.GetSawmill("loc").Level = LogLevel.Error;
+            logManager.GetSawmill("loc").Level = LogLevel.Warning;
 
 #if DEBUG_ONLY_FCE_INFO
 #if DEBUG_ONLY_FCE_LOG
@@ -565,7 +574,6 @@ namespace Robust.Client
 
             _networkManager.Shutdown("Client shutting down");
             _midiManager.Shutdown();
-            IoCManager.Resolve<IEntityLookup>().Shutdown();
             _entityManager.Shutdown();
             _clyde.Shutdown();
             _clydeAudio.Shutdown();

Robust.Client/GameControllerOptions.cs

@@ -3,7 +3,7 @@ using Robust.Shared.Utility;
 
 namespace Robust.Client
 {
-    public class GameControllerOptions
+    public sealed class GameControllerOptions
     {
         /// <summary>
         ///     Whether content sandboxing will be enabled & enforced.

Robust.Client/GameObjects/ClientComponentFactory.cs

@@ -6,7 +6,7 @@ using Robust.Shared.Reflection;
 
 namespace Robust.Client.GameObjects
 {
-    internal class ClientComponentFactory : ComponentFactory
+    internal sealed class ClientComponentFactory : ComponentFactory
     {
         public ClientComponentFactory(IDynamicTypeFactoryInternal typeFactory, IReflectionManager reflectionManager, IConsoleHost conHost)
             : base(typeFactory, reflectionManager, conHost)
@@ -29,13 +29,9 @@ namespace Robust.Client.GameObjects
             RegisterClass<EyeComponent>();
             RegisterClass<AnimationPlayerComponent>();
             RegisterClass<TimerComponent>();
-
-#if DEBUG
             RegisterClass<DebugExceptionOnAddComponent>();
             RegisterClass<DebugExceptionInitializeComponent>();
             RegisterClass<DebugExceptionStartupComponent>();
-#endif
-
         }
     }
 }

Robust.Client/GameObjects/ClientEntityManager.cs

@@ -27,7 +27,6 @@ namespace Robust.Client.GameObjects
         public override void Initialize()
         {
             SetupNetworking();
-            ReceivedComponentMessage += (_, compMsg) => DispatchComponentMessage(compMsg);
             ReceivedSystemMessage += (_, systemMsg) => EventBus.RaiseEvent(EventSource.Network, systemMsg);
 
             base.Initialize();
@@ -52,9 +51,6 @@ namespace Robust.Client.GameObjects
 
         public override IEntityNetworkManager EntityNetManager => this;
 
-        /// <inheritdoc />
-        public event EventHandler<NetworkComponentMessage>? ReceivedComponentMessage;
-
         /// <inheritdoc />
         public event EventHandler<object>? ReceivedSystemMessage;
 
@@ -105,25 +101,6 @@ namespace Robust.Client.GameObjects
             throw new NotSupportedException();
         }
 
-        /// <inheritdoc />
-        [Obsolete("Component Messages are deprecated, use Entity Events instead.")]
-        public void SendComponentNetworkMessage(INetChannel? channel, EntityUid entity, IComponent component, ComponentMessage message)
-        {
-            var netId = ComponentFactory.GetRegistration(component.GetType()).NetID;
-
-            if (!netId.HasValue)
-                throw new ArgumentException($"Component {component.Name} does not have a NetID.", nameof(component));
-
-            var msg = _networkManager.CreateNetMessage<MsgEntity>();
-            msg.Type = EntityMessageType.ComponentMessage;
-            msg.EntityUid = entity;
-            msg.NetId = netId.Value;
-            msg.ComponentMessage = message;
-            msg.SourceTick = _gameTiming.CurTick;
-
-            _networkManager.ClientSendMessage(msg);
-        }
-
         private void HandleEntityNetworkMessage(MsgEntity message)
         {
             if (message.SourceTick <= _gameStateManager.CurServerTick)
@@ -142,10 +119,6 @@ namespace Robust.Client.GameObjects
         {
             switch (message.Type)
             {
-                case EntityMessageType.ComponentMessage:
-                    ReceivedComponentMessage?.Invoke(this, new NetworkComponentMessage(message));
-                    return;
-
                 case EntityMessageType.SystemMessage:
                     var msg = message.SystemMessage;
                     var sessionType = typeof(EntitySessionMessage<>).MakeGenericType(msg.GetType());

Robust.Client/GameObjects/ComponentStateApplyException.cs

@@ -4,6 +4,7 @@ using System.Runtime.Serialization;
 namespace Robust.Client.GameObjects
 {
     [Serializable]
+    [Virtual]
     public class ComponentStateApplyException : Exception
     {
         public ComponentStateApplyException()

Robust.Client/GameObjects/Components/Animations/AnimationPlayerComponent.cs

@@ -13,8 +13,6 @@ namespace Robust.Client.GameObjects
     {
         // TODO: Give this component a friend someday. Way too much content shit to change atm ._.
 
-        public override string Name => "AnimationPlayer";
-
         public int PlayingAnimationCount => PlayingAnimations.Count;
 
         internal readonly Dictionary<string, AnimationPlayback> PlayingAnimations

Robust.Client/GameObjects/Components/Appearance/AppearanceVisualizer.cs

@@ -1,4 +1,5 @@
-using Robust.Shared.GameObjects;
+using System;
+using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization.Manager.Attributes;
 
 namespace Robust.Client.GameObjects;
@@ -14,6 +15,7 @@ public abstract class AppearanceVisualizer
     ///     Initializes an entity to be managed by this appearance controller.
     ///     DO NOT assume this is your only entity. Visualizers are shared.
     /// </summary>
+    [Obsolete("Subscribe to your component being initialised instead.")]
     public virtual void InitializeEntity(EntityUid entity)
     {
     }
@@ -23,6 +25,7 @@ public abstract class AppearanceVisualizer
     ///     Update its visuals here.
     /// </summary>
     /// <param name="component">The appearance component of the entity that might need updating.</param>
+    [Obsolete("Subscribe to AppearanceChangeEvent instead.")]
     public virtual void OnChangeData(AppearanceComponent component)
     {
     }

Robust.Client/GameObjects/Components/Appearance/ClientAppearanceComponent.cs

@@ -1,4 +1,5 @@
 using System.Collections.Generic;
+using Robust.Shared.Analyzers;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization.Manager.Attributes;
 using Robust.Shared.ViewVariables;
@@ -9,39 +10,10 @@ namespace Robust.Client.GameObjects;
 /// This is the client instance of <see cref="AppearanceComponent"/>.
 /// </summary>
 [RegisterComponent]
-[ComponentReference(typeof(AppearanceComponent))]
+[ComponentReference(typeof(AppearanceComponent)), Friend(typeof(AppearanceSystem))]
 public sealed class ClientAppearanceComponent : AppearanceComponent
 {
-    [ViewVariables]
-    private bool _appearanceDirty;
-
     [ViewVariables]
     [DataField("visuals")]
     internal List<AppearanceVisualizer> Visualizers = new();
-
-    protected override void MarkDirty()
-    {
-        if (_appearanceDirty)
-            return;
-
-        EntitySystem.Get<AppearanceSystem>().EnqueueUpdate(this);
-        _appearanceDirty = true;
-    }
-
-    protected override void Initialize()
-    {
-        base.Initialize();
-
-        foreach (var visual in Visualizers)
-        {
-            visual.InitializeEntity(Owner);
-        }
-
-        MarkDirty();
-    }
-
-    internal void UnmarkDirty()
-    {
-        _appearanceDirty = false;
-    }
 }

Robust.Client/GameObjects/Components/Eye/EyeComponent.cs

@@ -9,14 +9,11 @@ using Robust.Shared.ViewVariables;
 namespace Robust.Client.GameObjects
 {
     [ComponentReference(typeof(SharedEyeComponent))]
-    public class EyeComponent : SharedEyeComponent
+    public sealed class EyeComponent : SharedEyeComponent
     {
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly IEntityManager _entityManager = default!;
 
-        /// <inheritdoc />
-        public override string Name => "Eye";
-
         [ViewVariables]
         private Eye? _eye = default!;
 

Robust.Client/GameObjects/Components/Icon/IconComponent.cs

@@ -1,4 +1,4 @@
-using Robust.Client.Graphics;
+using Robust.Client.Graphics;
 using Robust.Client.ResourceManagement;
 using Robust.Client.Utility;
 using Robust.Shared.GameObjects;
@@ -12,9 +12,8 @@ using Robust.Shared.Utility;
 namespace Robust.Client.GameObjects
 {
     [RegisterComponent]
-    public class IconComponent : Component, ISerializationHooks
+    public sealed class IconComponent : Component, ISerializationHooks
     {
-        public override string Name => "Icon";
         public IDirectionalTextureProvider? Icon { get; private set; }
 
         [DataField("sprite")]

Robust.Client/GameObjects/Components/Input/InputComponent.cs

@@ -1,4 +1,4 @@
-using Robust.Shared.GameObjects;
+using Robust.Shared.GameObjects;
 using Robust.Shared.Input;
 using Robust.Shared.Serialization.Manager.Attributes;
 using Robust.Shared.ViewVariables;
@@ -8,11 +8,8 @@ namespace Robust.Client.GameObjects
     /// <summary>
     ///     Defines data fields used in the <see cref="InputSystem"/>.
     /// </summary>
-    public class InputComponent : Component
+    public sealed class InputComponent : Component
     {
-        /// <inheritdoc />
-        public override string Name => "Input";
-
         /// <summary>
         ///     The context that will be made active for a client that attaches to this entity.
         /// </summary>

Robust.Client/GameObjects/Components/Light/ClientOccluderComponent.cs

@@ -8,7 +8,7 @@ using Robust.Shared.ViewVariables;
 namespace Robust.Client.GameObjects
 {
     [ComponentReference(typeof(OccluderComponent))]
-    internal sealed class ClientOccluderComponent : OccluderComponent
+    public sealed class ClientOccluderComponent : OccluderComponent
     {
         [Dependency] private readonly IMapManager _mapManager = default!;
         [Dependency] private readonly IEntityManager _entityManager = default!;
@@ -40,13 +40,14 @@ namespace Robust.Client.GameObjects
 
         public void AnchorStateChanged()
         {
-            SendDirty();
+            var xform = _entityManager.GetComponent<TransformComponent>(Owner);
+            SendDirty(xform);
 
-            if(!_entityManager.GetComponent<TransformComponent>(Owner).Anchored)
+            if(!xform.Anchored)
                 return;
 
-            var grid = _mapManager.GetGrid(_entityManager.GetComponent<TransformComponent>(Owner).GridID);
-            _lastPosition = (_entityManager.GetComponent<TransformComponent>(Owner).GridID, grid.TileIndicesFor(_entityManager.GetComponent<TransformComponent>(Owner).Coordinates));
+            var grid = _mapManager.GetGrid(xform.GridID);
+            _lastPosition = (xform.GridID, grid.TileIndicesFor(xform.Coordinates));
         }
 
         protected override void Shutdown()
@@ -56,9 +57,10 @@ namespace Robust.Client.GameObjects
             SendDirty();
         }
 
-        private void SendDirty()
+        private void SendDirty(TransformComponent? xform = null)
         {
-            if (_entityManager.GetComponent<TransformComponent>(Owner).Anchored)
+            xform ??= _entityManager.GetComponent<TransformComponent>(Owner);
+            if (xform.Anchored)
             {
                 _entityManager.EventBus.RaiseEvent(EventSource.Local,
                     new OccluderDirtyEvent(Owner, _lastPosition));
@@ -69,13 +71,29 @@ namespace Robust.Client.GameObjects
         {
             Occluding = OccluderDir.None;
 
-            if (Deleted || !_entityManager.GetComponent<TransformComponent>(Owner).Anchored)
+            if (Deleted)
+                return;
+
+            // Content may want to override the default behavior for occlusion.
+            var xform = _entityManager.GetComponent<TransformComponent>(Owner);
+            var ev = new OccluderDirectionsEvent
             {
+                Component = xform,
+            };
+
+            _entityManager.EventBus.RaiseLocalEvent(Owner, ref ev);
+
+            if (ev.Handled)
+            {
+                Occluding = ev.Directions;
                 return;
             }
 
-            var grid = _mapManager.GetGrid(_entityManager.GetComponent<TransformComponent>(Owner).GridID);
-            var position = _entityManager.GetComponent<TransformComponent>(Owner).Coordinates;
+            if (!xform.Anchored)
+                return;
+
+            var grid = _mapManager.GetGrid(xform.GridID);
+            var position = xform.Coordinates;
             void CheckDir(Direction dir, OccluderDir oclDir)
             {
                 foreach (var neighbor in grid.GetInDir(position, dir))
@@ -88,7 +106,7 @@ namespace Robust.Client.GameObjects
                 }
             }
 
-            var angle = _entityManager.GetComponent<TransformComponent>(Owner).LocalRotation;
+            var angle = xform.LocalRotation;
             var dirRolling = angle.GetCardinalDir();
             // dirRolling starts at effective south
 
@@ -103,15 +121,28 @@ namespace Robust.Client.GameObjects
 
             CheckDir(dirRolling, OccluderDir.East);
         }
+    }
 
-        [Flags]
-        internal enum OccluderDir : byte
-        {
-            None = 0,
-            North = 1,
-            East = 1 << 1,
-            South = 1 << 2,
-            West = 1 << 3,
-        }
+    [Flags]
+    public enum OccluderDir : byte
+    {
+        None = 0,
+        North = 1,
+        East = 1 << 1,
+        South = 1 << 2,
+        West = 1 << 3,
+    }
+
+    /// <summary>
+    /// Raised by occluders when trying to get occlusion directions.
+    /// </summary>
+    [ByRefEvent]
+    public struct OccluderDirectionsEvent
+    {
+        public bool Handled = false;
+        public OccluderDir Directions = OccluderDir.None;
+        public TransformComponent Component = default!;
+
+        public OccluderDirectionsEvent() {}
     }
 }

Robust.Client/GameObjects/Components/Light/PointLightComponent.cs

@@ -11,7 +11,7 @@ namespace Robust.Client.GameObjects
 {
     [RegisterComponent]
     [ComponentReference(typeof(SharedPointLightComponent))]
-    public class PointLightComponent : SharedPointLightComponent, ISerializationHooks
+    public sealed class PointLightComponent : SharedPointLightComponent, ISerializationHooks
     {
         [Dependency] private readonly IEntityManager _entityManager = default!;
 
@@ -96,26 +96,6 @@ namespace Robust.Client.GameObjects
         [ViewVariables(VVAccess.ReadWrite)]
         public Texture? Mask { get; set; }
 
-        [ViewVariables(VVAccess.ReadWrite)]
-        [Animatable]
-        public float Energy
-        {
-            get => _energy;
-            set => _energy = value;
-        }
-
-        /// <summary>
-        ///     Soft shadow strength multiplier.
-        ///     Has no effect if soft shadows are not enabled.
-        /// </summary>
-        [ViewVariables(VVAccess.ReadWrite)]
-        [Animatable]
-        public float Softness
-        {
-            get => _softness;
-            set => _softness = value;
-        }
-
         [ViewVariables(VVAccess.ReadWrite)]
         public bool VisibleNested
         {
@@ -134,10 +114,7 @@ namespace Robust.Client.GameObjects
         [DataField("autoRot")]
         private bool _maskAutoRotate;
         private Angle _rotation;
-        [DataField("energy")]
-        private float _energy = 1f;
-        [DataField("softness")]
-        private float _softness = 1f;
+
         [DataField("mask")]
         internal string? _maskPath;
 
@@ -162,7 +139,7 @@ namespace Robust.Client.GameObjects
         internal RenderingTreeComponent? RenderTree { get; set; }
     }
 
-    public class PointLightRadiusChangedEvent : EntityEventArgs
+    public sealed class PointLightRadiusChangedEvent : EntityEventArgs
     {
         public PointLightComponent PointLightComponent { get; }
 

Robust.Client/GameObjects/Components/Renderable/ISpriteComponent.cs

@@ -25,6 +25,8 @@ namespace Robust.Client.GameObjects
         [Animatable]
         Vector2 Scale { get; set; }
 
+        Box2 Bounds { get; }
+
         /// <summary>
         ///     A rotation applied to all layers.
         /// </summary>
@@ -119,7 +121,8 @@ namespace Robust.Client.GameObjects
         ///     This is useful to allow layer map configs to be defined in prototypes,
         ///     while still allowing code to create configs if they're absent.
         /// </remarks>
-        void LayerMapReserveBlank(object key);
+        /// <returns>Index of the new layer.</returns>
+        int LayerMapReserveBlank(object key);
 
         /// <summary>
         ///     Adds a layer without texture (thus falling back to the error texture).
@@ -145,8 +148,8 @@ namespace Robust.Client.GameObjects
         void RemoveLayer(int layer);
         void RemoveLayer(object layerKey);
 
-        void LayerSetShader(int layer, ShaderInstance shader);
-        void LayerSetShader(object layerKey, ShaderInstance shader);
+        void LayerSetShader(int layer, ShaderInstance shader, string? prototype = null);
+        void LayerSetShader(object layerKey, ShaderInstance shader, string? prototype = null);
         void LayerSetShader(int layer, string shaderName);
         void LayerSetShader(object layerKey, string shaderName);
 
@@ -217,8 +220,8 @@ namespace Robust.Client.GameObjects
         int GetLayerDirectionCount(ISpriteLayer layer);
 
         /// <summary>
-        ///     Calculate sprite bounding box in world-space coordinates.
+        ///     Calculate the rotated sprite bounding box in world-space coordinates.
         /// </summary>
-        Box2 CalculateBoundingBox(Vector2 worldPos);
+        Box2Rotated CalculateRotatedBoundingBox(Vector2 worldPosition, Angle worldRotation, IEye? eye = null);
     }
 }

Robust.Client/GameObjects/Components/Renderable/ISpriteLayer.cs

@@ -25,8 +25,6 @@ namespace Robust.Client.GameObjects
 
         RSI.State.Direction EffectiveDirection(Angle worldRotation);
 
-        Vector2 LocalToLayer(Vector2 localPos);
-
         /// <summary>
         ///     Layer size in pixels.
         ///     Don't account layer scale or sprite world transform.

Robust.Client/GameObjects/Components/Renderable/SpriteBoundsOverlay.cs

@@ -57,7 +57,7 @@ namespace Robust.Client.GameObjects
         private bool _enabled;
     }
 
-    public class SpriteBoundsOverlay : Overlay
+    public sealed class SpriteBoundsOverlay : Overlay
     {
         public override OverlaySpace Space => OverlaySpace.WorldSpace;
 
@@ -84,10 +84,16 @@ namespace Robust.Client.GameObjects
 
                 foreach (var sprite in comp.SpriteTree.QueryAabb(localAABB))
                 {
-                    var worldPos = _entityManager.GetComponent<TransformComponent>(sprite.Owner).WorldPosition;
-                    var bounds = sprite.CalculateBoundingBox(worldPos);
+                    var (worldPos, worldRot) = _entityManager.GetComponent<TransformComponent>(sprite.Owner).GetWorldPositionRotation();
+                    var bounds = sprite.CalculateRotatedBoundingBox(worldPos, worldRot);
+
+                    // Get scaled down bounds used to indicate the "south" of a sprite.
+                    var localBound = bounds.Box;
+                    var smallLocal = localBound.Scale(0.2f).Translated(-new Vector2(0f, localBound.Extents.Y));
+                    var southIndicator = new Box2Rotated(smallLocal, bounds.Rotation, bounds.Origin);
+
                     handle.DrawRect(bounds, Color.Red.WithAlpha(0.2f));
-                    handle.DrawRect(bounds.Scale(0.2f).Translated(-new Vector2(0f, bounds.Extents.Y)), Color.Blue.WithAlpha(0.5f));
+                    handle.DrawRect(southIndicator, Color.Blue.WithAlpha(0.5f));
                 }
             }
         }

Robust.Client/GameObjects/Components/RenderingTreeComponent.cs

@@ -6,8 +6,6 @@ namespace Robust.Client.GameObjects
     [RegisterComponent]
     public sealed class RenderingTreeComponent : Component
     {
-        public override string Name => "RenderingTree";
-
         internal DynamicTree<SpriteComponent> SpriteTree { get; set; } = default!;
         internal DynamicTree<PointLightComponent> LightTree { get; set; } = default!;
     }

Robust.Client/GameObjects/Components/UserInterface/ClientUserInterfaceComponent.cs

@@ -11,7 +11,7 @@ using Robust.Shared.ViewVariables;
 namespace Robust.Client.GameObjects
 {
     [ComponentReference(typeof(SharedUserInterfaceComponent))]
-    public class ClientUserInterfaceComponent : SharedUserInterfaceComponent, ISerializationHooks
+    public sealed class ClientUserInterfaceComponent : SharedUserInterfaceComponent, ISerializationHooks
     {
         [Dependency] private readonly IReflectionManager _reflectionManager = default!;
         [Dependency] private readonly IDynamicTypeFactory _dynamicTypeFactory = default!;

Robust.Client/GameObjects/EntitySystems/AnimationPlayerSystem.cs

@@ -62,6 +62,12 @@ namespace Robust.Client.GameObjects
             Play(component, animation, key);
         }
 
+        public void Play(EntityUid uid, AnimationPlayerComponent? component, Animation animation, string key)
+        {
+            component ??= EntityManager.EnsureComponent<AnimationPlayerComponent>(uid);
+            Play(component, animation, key);
+        }
+
         /// <summary>
         ///     Start playing an animation.
         /// </summary>
@@ -79,6 +85,14 @@ namespace Robust.Client.GameObjects
                    component.PlayingAnimations.ContainsKey(key);
         }
 
+        public bool HasRunningAnimation(EntityUid uid, AnimationPlayerComponent? component, string key)
+        {
+            if (component == null)
+                TryComp(uid, out component);
+
+            return component != null && component.PlayingAnimations.ContainsKey(key);
+        }
+
         public bool HasRunningAnimation(AnimationPlayerComponent component, string key)
         {
             return component.PlayingAnimations.ContainsKey(key);
@@ -88,6 +102,18 @@ namespace Robust.Client.GameObjects
         {
             component.PlayingAnimations.Remove(key);
         }
+
+        public void Stop(EntityUid uid, string key)
+        {
+            if (!TryComp<AnimationPlayerComponent>(uid, out var player)) return;
+            player.PlayingAnimations.Remove(key);
+        }
+
+        public void Stop(EntityUid uid, AnimationPlayerComponent? component, string key)
+        {
+            if (!Resolve(uid, ref component, false)) return;
+            component.PlayingAnimations.Remove(key);
+        }
     }
 
     public sealed class AnimationCompletedEvent : EntityEventArgs

Robust.Client/GameObjects/EntitySystems/AppearanceSystem.cs

@@ -1,17 +1,95 @@
+using System;
 using System.Collections.Generic;
 using JetBrains.Annotations;
 using Robust.Shared.GameObjects;
+using Robust.Shared.GameStates;
 
 namespace Robust.Client.GameObjects
 {
     [UsedImplicitly]
-    internal sealed class AppearanceSystem : EntitySystem
+    public sealed class AppearanceSystem : SharedAppearanceSystem
     {
         private readonly Queue<ClientAppearanceComponent> _queuedUpdates = new();
 
-        public void EnqueueUpdate(ClientAppearanceComponent component)
+        public override void Initialize()
         {
-            _queuedUpdates.Enqueue(component);
+            base.Initialize();
+
+            SubscribeLocalEvent<ClientAppearanceComponent, ComponentInit>(OnAppearanceInit);
+            SubscribeLocalEvent<ClientAppearanceComponent, ComponentHandleState>(OnAppearanceHandleState);
+        }
+
+        private void OnAppearanceInit(EntityUid uid, ClientAppearanceComponent component, ComponentInit args)
+        {
+            foreach (var visual in component.Visualizers)
+            {
+                visual.InitializeEntity(uid);
+            }
+
+            MarkDirty(component);
+        }
+
+        private void OnAppearanceHandleState(EntityUid uid, ClientAppearanceComponent component, ref ComponentHandleState args)
+        {
+            if (args.Current is not AppearanceComponentState actualState)
+                return;
+
+            var stateDiff = component.AppearanceData.Count != actualState.Data.Count;
+
+            if (!stateDiff)
+            {
+                foreach (var (key, value) in component.AppearanceData)
+                {
+                    if (!actualState.Data.TryGetValue(key, out var stateValue) ||
+                        !value.Equals(stateValue))
+                    {
+                        stateDiff = true;
+                        break;
+                    }
+                }
+            }
+
+            if (!stateDiff) return;
+
+            component.AppearanceData = CloneAppearanceData(actualState.Data);
+            MarkDirty(component);
+        }
+
+        /// <summary>
+        ///     Take in an appearance data dictionary and attempt to clone it.
+        /// </summary>
+        /// <remarks>
+        ///     As some appearance data values are not simple value-type objects, this is not just a shallow clone.
+        /// </remarks>
+        private Dictionary<object, object> CloneAppearanceData(Dictionary<object, object> data)
+        {
+            Dictionary<object, object> newDict = new(data.Count);
+
+            foreach (var (key, value) in data)
+            {
+                if (value.GetType().IsValueType)
+                    newDict[key] = value;
+                else if (value is ICloneable cloneable)
+                    newDict[key] = cloneable.Clone();
+                else
+                    throw new NotSupportedException("Invalid object in appearance data dictionary. Appearance data must be cloneable");
+            }
+
+            return newDict;
+        }
+
+        public override void MarkDirty(AppearanceComponent component)
+        {
+            if (component.AppearanceDirty)
+                return;
+
+            _queuedUpdates.Enqueue((ClientAppearanceComponent) component);
+            component.AppearanceDirty = true;
+        }
+
+        internal void UnmarkDirty(ClientAppearanceComponent component)
+        {
+            component.AppearanceDirty = false;
         }
 
         public override void FrameUpdate(float frameTime)
@@ -19,10 +97,10 @@ namespace Robust.Client.GameObjects
             while (_queuedUpdates.TryDequeue(out var appearance))
             {
                 if (appearance.Deleted)
-                    return;
+                    continue;
 
                 OnChangeData(appearance.Owner, appearance);
-                appearance.UnmarkDirty();
+                UnmarkDirty(appearance);
             }
         }
 
@@ -30,10 +108,30 @@ namespace Robust.Client.GameObjects
         {
             if (!Resolve(uid, ref appearanceComponent, false)) return;
 
+            var ev = new AppearanceChangeEvent
+            {
+                Component = appearanceComponent,
+                AppearanceData = appearanceComponent.AppearanceData,
+            };
+
+            // Give it AppearanceData so we can still keep the friend attribute on the component.
+            EntityManager.EventBus.RaiseLocalEvent(uid, ref ev);
+
+            // Eventually visualizers would be nuked and we'd just make them components instead.
             foreach (var visualizer in appearanceComponent.Visualizers)
             {
                 visualizer.OnChangeData(appearanceComponent);
             }
         }
     }
+
+    /// <summary>
+    ///     Raised whenever the appearance data for an entity changes.
+    /// </summary>
+    [ByRefEvent]
+    public struct AppearanceChangeEvent
+    {
+        public AppearanceComponent Component;
+        public IReadOnlyDictionary<object, object> AppearanceData;
+    }
 }

Robust.Client/GameObjects/EntitySystems/AudioSystem.cs

@@ -17,7 +17,7 @@ using Robust.Shared.Utility;
 namespace Robust.Client.GameObjects
 {
     [UsedImplicitly]
-    public class AudioSystem : SharedAudioSystem, IAudioSystem
+    public sealed class AudioSystem : SharedAudioSystem, IAudioSystem
     {
         [Dependency] private readonly IResourceCache _resourceCache = default!;
         [Dependency] private readonly IMapManager _mapManager = default!;
@@ -253,9 +253,15 @@ namespace Robust.Client.GameObjects
         /// </summary>
         /// <param name="stream">The audio stream to play.</param>
         /// <param name="audioParams"></param>
-        private IPlayingAudioStream Play(AudioStream stream, AudioParams? audioParams = null)
+        private IPlayingAudioStream? Play(AudioStream stream, AudioParams? audioParams = null)
         {
             var source = _clyde.CreateAudioSource(stream);
+
+            if (source == null)
+            {
+                return null;
+            }
+
             ApplyAudioParams(audioParams, source);
 
             source.SetGlobal();
@@ -303,6 +309,12 @@ namespace Robust.Client.GameObjects
             AudioParams? audioParams = null)
         {
             var source = _clyde.CreateAudioSource(stream);
+
+            if (source == null)
+            {
+                return null;
+            }
+
             if (!source.SetPosition(EntityManager.GetComponent<TransformComponent>(entity).WorldPosition))
             {
                 return Play(stream, fallbackCoordinates, fallbackCoordinates, audioParams);
@@ -356,6 +368,12 @@ namespace Robust.Client.GameObjects
             EntityCoordinates fallbackCoordinates, AudioParams? audioParams = null)
         {
             var source = _clyde.CreateAudioSource(stream);
+
+            if (source == null)
+            {
+                return null;
+            }
+
             if (!source.SetPosition(fallbackCoordinates.Position))
             {
                 source.Dispose();
@@ -402,7 +420,7 @@ namespace Robust.Client.GameObjects
             source.IsLooping = audioParams.Value.Loop;
         }
 
-        private class PlayingStream : IPlayingAudioStream
+        private sealed class PlayingStream : IPlayingAudioStream
         {
             public uint? NetIdentifier;
             public IClydeAudioSource Source = default!;

Robust.Client/GameObjects/EntitySystems/ClientOccluderSystem.cs

@@ -72,10 +72,13 @@ namespace Robust.Client.GameObjects
             var sender = ev.Sender;
             if (EntityManager.EntityExists(sender) &&
                 EntityManager.TryGetComponent(sender, out ClientOccluderComponent? iconSmooth)
-                && iconSmooth.Running)
+                && iconSmooth.Initialized)
             {
-                var grid1 = _mapManager.GetGrid(EntityManager.GetComponent<TransformComponent>(sender).GridID);
-                var coords = EntityManager.GetComponent<TransformComponent>(sender).Coordinates;
+                var xform = EntityManager.GetComponent<TransformComponent>(sender);
+                if (!_mapManager.TryGetGrid(xform.GridID, out var grid1))
+                    return;
+
+                var coords = xform.Coordinates;
 
                 _dirtyEntities.Enqueue(sender);
                 AddValidEntities(grid1.GetInDir(coords, Direction.North));
@@ -85,7 +88,7 @@ namespace Robust.Client.GameObjects
             }
 
             // Entity is no longer valid, update around the last position it was at.
-            if (ev.LastPosition.HasValue && _mapManager.TryGetGrid(ev.LastPosition.Value.grid, out var grid))
+            else if (ev.LastPosition.HasValue && _mapManager.TryGetGrid(ev.LastPosition.Value.grid, out var grid))
             {
                 var pos = ev.LastPosition.Value.pos;
 

Robust.Client/GameObjects/EntitySystems/ContainerSystem.cs

@@ -5,12 +5,14 @@ using Robust.Shared.Containers;
 using Robust.Shared.GameObjects;
 using Robust.Shared.GameStates;
 using Robust.Shared.IoC;
+using Robust.Shared.Log;
+using Robust.Shared.Map;
 using Robust.Shared.Serialization;
 using static Robust.Shared.Containers.ContainerManagerComponent;
 
 namespace Robust.Client.GameObjects
 {
-    public class ContainerSystem : SharedContainerSystem
+    public sealed class ContainerSystem : SharedContainerSystem
     {
         [Dependency] private readonly IRobustSerializer _serializer = default!;
         [Dependency] private readonly IDynamicTypeFactoryInternal _dynFactory = default!;
@@ -59,7 +61,7 @@ namespace Robust.Client.GameObjects
             {
                 if (!cast.ContainerSet.Any(data => data.Id == id))
                 {
-                    container.EmptyContainer(true);
+                    container.EmptyContainer(true, entMan: EntityManager);
                     container.Shutdown();
                     toDelete ??= new List<string>();
                     toDelete.Add(id);
@@ -131,12 +133,51 @@ namespace Robust.Client.GameObjects
                         continue;
                     }
 
+                    // If an entity is currently in the shadow realm, it means we probably left PVS and are now getting
+                    // back into range. We do not want to directly insert this entity, as IF the container and entity
+                    // transform states did not get sent simultaneously, the entity's transform will be modified by the
+                    // insert operation. This means it will then be reset to the shadow realm, causing it to be ejected
+                    // from the container. It would then subsequently be parented to the container without ever being
+                    // re-inserted, leading to the client seeing what should be hidden entities attached to
+                    // containers/players.
+                    if (Transform(entity).MapID == MapId.Nullspace)
+                    {
+                        AddExpectedEntity(entity, container);
+                        continue;
+                    }
+
                     if (!container.ContainedEntities.Contains(entity))
                         container.Insert(entity);
                 }
             }
         }
 
+        protected override void HandleParentChanged(ref EntParentChangedMessage message)
+        {
+            base.HandleParentChanged(ref message);
+
+            // If an entity warped in from null-space (i.e., re-entered PVS) and got attached to a container, do the same checks as for newly initialized entities.
+            if (message.OldParent != null && message.OldParent.Value.IsValid())
+                return;
+
+            if (!ExpectedEntities.TryGetValue(message.Entity, out var container))
+                return;
+
+            if (Transform(message.Entity).ParentUid != container.Owner)
+            {
+                // This container is expecting an entity... but it got parented to some other entity???
+                // Ah well, the sever should send a new container state that updates expected entities so just ignore it for now.
+                return;
+            }
+
+            RemoveExpectedEntity(message.Entity);
+
+            if (container.Deleted)
+                return;
+
+            container.Insert(message.Entity);
+        }
+
         private IContainer ContainerFactory(ContainerManagerComponent component, string containerType, string id)
         {
             var type = _serializer.FindSerializedType(typeof(IContainer), containerType);
@@ -169,68 +210,101 @@ namespace Robust.Client.GameObjects
         public override void FrameUpdate(float frameTime)
         {
             base.FrameUpdate(frameTime);
+            var pointQuery = EntityManager.GetEntityQuery<PointLightComponent>();
+            var spriteQuery = EntityManager.GetEntityQuery<SpriteComponent>();
+            var xformQuery = EntityManager.GetEntityQuery<TransformComponent>();
 
             foreach (var toUpdate in _updateQueue)
             {
-                if (EntityManager.Deleted(toUpdate))
-                {
+                if (Deleted(toUpdate))
                     continue;
-                }
 
-                UpdateEntityRecursively(toUpdate);
+                UpdateEntityRecursively(toUpdate, xformQuery, pointQuery, spriteQuery);
             }
 
             _updateQueue.Clear();
         }
 
-        private void UpdateEntityRecursively(EntityUid entity)
+        private void UpdateEntityRecursively(
+            EntityUid entity,
+            EntityQuery<TransformComponent> xformQuery,
+            EntityQuery<PointLightComponent> pointQuery,
+            EntityQuery<SpriteComponent> spriteQuery)
         {
-            // TODO: Since we are recursing down,
-            // we could cache ShowContents data here to speed it up for children.
-            // Am lazy though.
-            UpdateEntity(entity);
+            // Recursively go up parents and containers to see whether both sprites and lights need to be occluded
+            // Could maybe optimise this more by checking nearest parent that has sprite / light and whether it's container
+            // occluded but this probably isn't a big perf issue.
+            var xform = xformQuery.GetComponent(entity);
+            var parent = xform.ParentUid;
+            var child = entity;
+            var spriteOccluded = false;
+            var lightOccluded = false;
 
-            foreach (var child in EntityManager.GetComponent<TransformComponent>(entity).Children)
+            while (parent.IsValid() && !spriteOccluded && !lightOccluded)
             {
-                UpdateEntityRecursively(child.Owner);
+                var parentXform = xformQuery.GetComponent(parent);
+                if (TryComp<ContainerManagerComponent>(parent, out var manager) && manager.TryGetContainer(child, out var container))
+                {
+                    spriteOccluded = spriteOccluded || !container.ShowContents;
+                    lightOccluded = lightOccluded || container.OccludesLight;
+                }
+
+                child = parent;
+                parent = parentXform.ParentUid;
             }
+
+            // Alright so
+            // This is the CBT bit.
+            // The issue is we need to go through the children and re-check whether they are or are not contained.
+            // if they are contained then the occlusion values may need updating for all those children
+            UpdateEntity(entity, xform, xformQuery, pointQuery, spriteQuery, spriteOccluded, lightOccluded);
         }
 
-        private void UpdateEntity(EntityUid entity)
+        private void UpdateEntity(
+            EntityUid entity,
+            TransformComponent xform,
+            EntityQuery<TransformComponent> xformQuery,
+            EntityQuery<PointLightComponent> pointQuery,
+            EntityQuery<SpriteComponent> spriteQuery,
+            bool spriteOccluded,
+            bool lightOccluded)
         {
-            if (EntityManager.TryGetComponent(entity, out SpriteComponent? sprite))
+            if (spriteQuery.TryGetComponent(entity, out var sprite))
             {
-                sprite.ContainerOccluded = false;
-
-                // We have to recursively scan for containers upwards in case of nested containers.
-                var tempParent = entity;
-                while (tempParent.TryGetContainer(out var container))
-                {
-                    if (!container.ShowContents)
-                    {
-                        sprite.ContainerOccluded = true;
-                        break;
-                    }
-
-                    tempParent = container.Owner;
-                }
+                sprite.ContainerOccluded = spriteOccluded;
             }
 
-            if (EntityManager.TryGetComponent(entity, out PointLightComponent? light))
+            if (pointQuery.TryGetComponent(entity, out var light))
             {
-                light.ContainerOccluded = false;
+                light.ContainerOccluded = lightOccluded;
+            }
 
-                // We have to recursively scan for containers upwards in case of nested containers.
-                var tempParent = entity;
-                while (tempParent.TryGetContainer(out var container))
+            var childEnumerator = xform.ChildEnumerator;
+
+            // Try to avoid TryComp if we already know stuff is occluded.
+            if ((!spriteOccluded || !lightOccluded) && TryComp<ContainerManagerComponent>(entity, out var manager))
+            {
+                while (childEnumerator.MoveNext(out var child))
                 {
-                    if (container.OccludesLight)
+                    // Thank god it's by value and not by ref.
+                    var childSpriteOccluded = spriteOccluded;
+                    var childLightOccluded = lightOccluded;
+
+                    // We already know either sprite or light is not occluding so need to check container.
+                    if (manager.TryGetContainer(child.Value, out var container))
                     {
-                        light.ContainerOccluded = true;
-                        break;
+                        childSpriteOccluded = childSpriteOccluded || !container.ShowContents;
+                        childLightOccluded = childLightOccluded || container.OccludesLight;
                     }
 
-                    tempParent = container.Owner;
+                    UpdateEntity(child.Value, xformQuery.GetComponent(child.Value), xformQuery, pointQuery, spriteQuery, childSpriteOccluded, childLightOccluded);
+                }
+            }
+            else
+            {
+                while (childEnumerator.MoveNext(out var child))
+                {
+                    UpdateEntity(child.Value, xformQuery.GetComponent(child.Value), xformQuery, pointQuery, spriteQuery, spriteOccluded, lightOccluded);
                 }
             }
         }

Robust.Client/GameObjects/EntitySystems/DebugGridTileLookupSystem.cs

@@ -1,133 +0,0 @@
-#if DEBUG
-using System;
-using System.Text;
-using Robust.Client.Graphics;
-using Robust.Client.Input;
-using Robust.Client.UserInterface;
-using Robust.Client.UserInterface.Controls;
-using Robust.Shared.Console;
-using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
-using Robust.Shared.Map;
-using Robust.Shared.Maths;
-
-namespace Robust.Client.GameObjects
-{
-    internal sealed class DebugGridTileLookupSystem : EntitySystem
-    {
-        [Dependency] private readonly IEyeManager _eyeManager = default!;
-        [Dependency] private readonly IInputManager _inputManager = default!;
-        [Dependency] private readonly IMapManager _mapManager = default!;
-
-        public bool Enabled
-        {
-            get => _enabled;
-            set
-            {
-                if (_enabled == value) return;
-                _enabled = value;
-
-                if (_enabled)
-                {
-                    _label.Visible = true;
-                    LastTile = default;
-                }
-                else
-                {
-                    _label.Text = null;
-                    _label.Visible = false;
-                }
-            }
-        }
-
-        private bool _enabled;
-
-        private (GridId Grid, Vector2i Indices) LastTile;
-
-        // Label and shit that follows cursor
-        private Label _label = new()
-        {
-            Visible = false,
-        };
-
-        public override void Initialize()
-        {
-            base.Initialize();
-            SubscribeNetworkEvent<SendGridTileLookupMessage>(HandleSentEntities);
-            IoCManager.Resolve<IUserInterfaceManager>().StateRoot.AddChild(_label);
-        }
-
-        public override void Shutdown()
-        {
-            base.Shutdown();
-            IoCManager.Resolve<IUserInterfaceManager>().StateRoot.RemoveChild(_label);
-        }
-
-        private void RequestEntities(GridId gridId, Vector2i indices)
-        {
-            if (gridId == GridId.Invalid) return;
-            RaiseNetworkEvent(new RequestGridTileLookupMessage(gridId, indices));
-        }
-
-        private void HandleSentEntities(SendGridTileLookupMessage message)
-        {
-            if (!Enabled) return;
-            var text = new StringBuilder();
-            text.AppendLine($"GridId: {LastTile.Grid}, Tile: {LastTile.Indices}");
-
-            for (var i = 0; i < message.Entities.Count; i++)
-            {
-                var entity = message.Entities[i];
-
-                if (!EntityManager.EntityExists(entity)) continue;
-
-                text.AppendLine((string) EntityManager.ToPrettyString(entity));
-            }
-
-            _label.Text = text.ToString();
-        }
-
-        public override void FrameUpdate(float frameTime)
-        {
-            base.FrameUpdate(frameTime);
-            if (!Enabled) return;
-
-            var mousePos = _inputManager.MouseScreenPosition;
-            var worldPos = _eyeManager.ScreenToMap(mousePos);
-
-            GridId gridId;
-            Vector2i tile;
-
-            if (_mapManager.TryFindGridAt(worldPos, out var grid))
-            {
-                gridId = grid.Index;
-                tile = grid.WorldToTile(worldPos.Position);
-            }
-            else
-            {
-                gridId = GridId.Invalid;
-                tile = new Vector2i((int) MathF.Floor(worldPos.Position.X), (int) MathF.Floor(worldPos.Position.Y));
-            }
-
-            LayoutContainer.SetPosition(_label, mousePos.Position);
-
-            if ((gridId, tile).Equals(LastTile)) return;
-
-            _label.Text = null;
-            LastTile = (gridId, tile);
-            RequestEntities(gridId, tile);
-        }
-    }
-
-    internal sealed class RequestTileEntities : IConsoleCommand
-    {
-        public string Command => "tilelookup";
-        public string Description => "Used for debugging GridTileLookupSystem";
-        public string Help => $"{Command}";
-        public void Execute(IConsoleShell shell, string argStr, string[] args)
-        {
-            EntitySystem.Get<DebugGridTileLookupSystem>().Enabled ^= true;
-        }
-    }
-}
-#endif

Robust.Client/GameObjects/EntitySystems/DebugLightTreeSystem.cs

@@ -25,7 +25,7 @@ namespace Robust.Client.GameObjects
                 if (_enabled)
                 {
                     _lightOverlay = new DebugLightOverlay(
-                        IoCManager.Resolve<IEntityLookup>(),
+                        EntitySystem.Get<EntityLookupSystem>(),
                         IoCManager.Resolve<IEyeManager>(),
                         IoCManager.Resolve<IMapManager>(),
                         Get<RenderingTreeSystem>());
@@ -44,7 +44,7 @@ namespace Robust.Client.GameObjects
 
         private sealed class DebugLightOverlay : Overlay
         {
-            private IEntityLookup _lookup;
+            private EntityLookupSystem _lookup;
             private IEyeManager _eyeManager;
             private IMapManager _mapManager;
 
@@ -52,7 +52,7 @@ namespace Robust.Client.GameObjects
 
             public override OverlaySpace Space => OverlaySpace.WorldSpace;
 
-            public DebugLightOverlay(IEntityLookup lookup, IEyeManager eyeManager, IMapManager mapManager, RenderingTreeSystem tree)
+            public DebugLightOverlay(EntityLookupSystem lookup, IEyeManager eyeManager, IMapManager mapManager, RenderingTreeSystem tree)
             {
                 _lookup = lookup;
                 _eyeManager = eyeManager;
@@ -72,7 +72,7 @@ namespace Robust.Client.GameObjects
                 {
                     foreach (var light in tree.LightTree)
                     {
-                        var aabb = _lookup.GetWorldAabbFromEntity(light.Owner);
+                        var aabb = _lookup.GetWorldAABB(light.Owner);
                         if (!aabb.Intersects(worldBounds)) continue;
 
                         args.WorldHandle.DrawRect(aabb, Color.Green.WithAlpha(0.1f));

Robust.Client/GameObjects/EntitySystems/EffectSystem.cs

@@ -15,7 +15,7 @@ using Robust.Shared.Enums;
 
 namespace Robust.Client.GameObjects
 {
-    public class EffectSystem : EntitySystem
+    public sealed class EffectSystem : EntitySystem
     {
         [Dependency] private readonly IGameTiming gameTiming = default!;
         [Dependency] private readonly IResourceCache resourceCache = default!;
@@ -94,7 +94,7 @@ namespace Robust.Client.GameObjects
             }
         }
 
-        private class Effect
+        private sealed class Effect
         {
             /// <summary>
             /// Effect Sprite
@@ -323,7 +323,7 @@ namespace Robust.Client.GameObjects
         {
             private readonly IPlayerManager _playerManager;
 
-            public override OverlaySpace Space => OverlaySpace.WorldSpace;
+            public override OverlaySpace Space => OverlaySpace.WorldSpaceBelowFOV;
 
             private readonly ShaderInstance _unshadedShader;
             private readonly EffectSystem _owner;
@@ -342,7 +342,6 @@ namespace Robust.Client.GameObjects
                 var map = _owner.eyeManager.CurrentMap;
 
                 var worldHandle = args.WorldHandle;
-                ShaderInstance? currentShader = null;
 
                 if (_playerManager.LocalPlayer?.ControlledEntity is not {} playerEnt)
                     return;
@@ -362,13 +361,8 @@ namespace Robust.Client.GameObjects
                         continue;
                     }
 
-                    var newShader = effect.Shaded ? null : _unshadedShader;
-
-                    if (newShader != currentShader)
-                    {
-                        worldHandle.UseShader(newShader);
-                        currentShader = newShader;
-                    }
+                    if (!effect.Shaded)
+                        worldHandle.UseShader(_unshadedShader);
 
                     // TODO: Should be doing matrix transformations
                     var effectSprite = effect.EffectSprite;
@@ -377,6 +371,9 @@ namespace Robust.Client.GameObjects
                         (attachedXform?.Coordinates ?? effect.Coordinates)
                         .Offset(effect.AttachedOffset);
 
+                    // If we've never seen the entity before then can't resolve coordinates.
+                    if (!coordinates.IsValid(_entityManager)) continue;
+
                     // ???
                     var rotation = attachedXform?.WorldRotation ?? _entityManager.GetComponent<TransformComponent>(coordinates.EntityId).WorldRotation;
 
@@ -386,6 +383,9 @@ namespace Robust.Client.GameObjects
                     var rotatedBox = new Box2Rotated(effectArea, effect.Rotation + rotation, effectOrigin);
 
                     worldHandle.DrawTextureRect(effectSprite, rotatedBox, ToColor(effect.Color));
+
+                    if (!effect.Shaded)
+                        worldHandle.UseShader(null);
                 }
             }
         }

Robust.Client/GameObjects/EntitySystems/EyeUpdateSystem.cs

@@ -20,7 +20,7 @@ namespace Robust.Client.GameObjects
     /// Updates the position of every Eye every frame, so that the camera follows the player around.
     /// </summary>
     [UsedImplicitly]
-    public class EyeUpdateSystem : EntitySystem
+    public sealed class EyeUpdateSystem : EntitySystem
     {
         /// <inheritdoc />
         public override void Initialize()

Robust.Client/GameObjects/EntitySystems/GridChunkBoundsDebugSystem.cs

@@ -1,4 +1,3 @@
-using System;
 using Robust.Client.Graphics;
 using Robust.Shared.Enums;
 using Robust.Shared.GameObjects;
@@ -11,8 +10,12 @@ using Robust.Shared.Utility;
 
 namespace Robust.Client.GameObjects
 {
-    public class GridChunkBoundsDebugSystem : EntitySystem
+    public sealed class GridChunkBoundsDebugSystem : EntitySystem
     {
+        [Dependency] private readonly IEyeManager _eyeManager = default!;
+        [Dependency] private readonly IMapManager _mapManager = default!;
+        [Dependency] private readonly IOverlayManager _overlayManager = default!;
+
         private GridChunkBoundsOverlay? _overlay;
 
         public bool Enabled
@@ -29,14 +32,14 @@ namespace Robust.Client.GameObjects
                     DebugTools.Assert(_overlay == null);
                     _overlay = new GridChunkBoundsOverlay(
                         EntityManager,
-                        IoCManager.Resolve<IEyeManager>(),
-                        IoCManager.Resolve<IMapManager>());
+                        _eyeManager,
+                        _mapManager);
 
-                    IoCManager.Resolve<IOverlayManager>().AddOverlay(_overlay);
+                    _overlayManager.AddOverlay(_overlay);
                 }
                 else
                 {
-                    IoCManager.Resolve<IOverlayManager>().RemoveOverlay(_overlay!);
+                    _overlayManager.RemoveOverlay(_overlay!);
                     _overlay = null;
                 }
             }
@@ -63,7 +66,7 @@ namespace Robust.Client.GameObjects
         protected internal override void Draw(in OverlayDrawArgs args)
         {
             var currentMap = _eyeManager.CurrentMap;
-            var viewport = _eyeManager.GetWorldViewport();
+            var viewport = args.WorldBounds;
             var worldHandle = args.WorldHandle;
 
             foreach (var grid in _mapManager.FindGridsIntersecting(currentMap, viewport))

Robust.Client/GameObjects/EntitySystems/GridRenderingSystem.cs

@@ -0,0 +1,19 @@
+using Robust.Client.Graphics;
+using Robust.Shared.GameObjects;
+
+namespace Robust.Client.GameObjects;
+
+internal class GridRenderingSystem : EntitySystem
+{
+    private readonly IClydeInternal _clyde;
+
+    public GridRenderingSystem(IClydeInternal clyde)
+    {
+        _clyde = clyde;
+    }
+
+    public override void Initialize()
+    {
+        _clyde.RegisterGridEcsEvents();
+    }
+}

Robust.Client/GameObjects/EntitySystems/InputSystem.cs

@@ -4,11 +4,15 @@ using Robust.Client.Input;
 using Robust.Client.Player;
 using Robust.Shared;
 using Robust.Shared.Configuration;
+using Robust.Shared.Console;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Input;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
+using Robust.Shared.Map;
+using Robust.Shared.Maths;
 using Robust.Shared.Players;
+using Robust.Shared.Timing;
 using Robust.Shared.Utility;
 
 namespace Robust.Client.GameObjects
@@ -16,11 +20,13 @@ namespace Robust.Client.GameObjects
     /// <summary>
     ///     Client-side processing of all input commands through the simulation.
     /// </summary>
-    public class InputSystem : SharedInputSystem
+    public sealed class InputSystem : SharedInputSystem
     {
         [Dependency] private readonly IInputManager _inputManager = default!;
         [Dependency] private readonly IPlayerManager _playerManager = default!;
         [Dependency] private readonly IClientGameStateManager _stateManager = default!;
+        [Dependency] private readonly IConsoleHost _conHost = default!;
+        [Dependency] private readonly IGameTiming _timing = default!;
 
         private readonly IPlayerCommandStates _cmdStates = new PlayerCommandStates();
 
@@ -108,6 +114,43 @@ namespace Robust.Client.GameObjects
         public override void Initialize()
         {
             SubscribeLocalEvent<PlayerAttachSysMessage>(OnAttachedEntityChanged);
+
+            _conHost.RegisterCommand("incmd",
+                "Inserts an input command into the simulation",
+                "incmd <KeyFunction> <d|u KeyState> <wxPos> <wyPos>",
+                GenerateInputCommand);
+        }
+
+        public override void Shutdown()
+        {
+            base.Shutdown();
+
+            _conHost.UnregisterCommand("incmd");
+        }
+
+        private void GenerateInputCommand(IConsoleShell shell, string argstr, string[] args)
+        {
+            var localPlayer = _playerManager.LocalPlayer;
+            if(localPlayer is null)
+                return;
+
+            var pent = localPlayer.ControlledEntity;
+            if(pent is null)
+                return;
+
+            BoundKeyFunction keyFunction = new BoundKeyFunction(args[0]);
+            BoundKeyState state = args[1] == "u" ? BoundKeyState.Up: BoundKeyState.Down;
+
+            var pxform = Transform(pent.Value);
+            var wPos = pxform.WorldPosition + new Vector2(float.Parse(args[2]), float.Parse(args[3]));
+            var coords = EntityCoordinates.FromMap(EntityManager, pent.Value, new MapCoordinates(wPos, pxform.MapID));
+
+            var funcId = _inputManager.NetworkBindMap.KeyFunctionID(keyFunction);
+
+            var message = new FullInputCmdMessage(_timing.CurTick, _timing.TickFraction, funcId, state,
+                coords, new ScreenCoordinates(0, 0, default), EntityUid.Invalid);
+
+            HandleInputCommand(localPlayer.Session, keyFunction, message);
         }
 
         private void OnAttachedEntityChanged(PlayerAttachSysMessage message)
@@ -163,7 +206,7 @@ namespace Robust.Client.GameObjects
     /// <summary>
     ///     Entity system message that is raised when the player changes attached entities.
     /// </summary>
-    public class PlayerAttachSysMessage : EntityEventArgs
+    public sealed class PlayerAttachSysMessage : EntityEventArgs
     {
         /// <summary>
         ///     New entity the player is attached to.
@@ -180,7 +223,7 @@ namespace Robust.Client.GameObjects
         }
     }
 
-    public class PlayerAttachedEvent : EntityEventArgs
+    public sealed class PlayerAttachedEvent : EntityEventArgs
     {
         public PlayerAttachedEvent(EntityUid entity)
         {
@@ -190,7 +233,7 @@ namespace Robust.Client.GameObjects
         public EntityUid Entity { get; }
     }
 
-    public class PlayerDetachedEvent : EntityEventArgs
+    public sealed class PlayerDetachedEvent : EntityEventArgs
     {
         public PlayerDetachedEvent(EntityUid entity)
         {

Robust.Client/GameObjects/EntitySystems/MidiSystem.cs

@@ -4,7 +4,7 @@ using Robust.Shared.IoC;
 
 namespace Robust.Client.GameObjects
 {
-    public class MidiSystem : EntitySystem
+    public sealed class MidiSystem : EntitySystem
     {
         [Dependency] private readonly IMidiManager _midiManager = default!;
 

Robust.Client/GameObjects/EntitySystems/PointLightSystem.cs

@@ -8,6 +8,7 @@ namespace Robust.Client.GameObjects
     public sealed class PointLightSystem : SharedPointLightSystem
     {
         [Dependency] private readonly IResourceCache _resourceCache = default!;
+        [Dependency] private readonly RenderingTreeSystem _renderingTreeSystem = default!;
 
         public override void Initialize()
         {
@@ -19,16 +20,14 @@ namespace Robust.Client.GameObjects
         private void HandleInit(EntityUid uid, PointLightComponent component, ComponentInit args)
         {
             UpdateMask(component);
+            RaiseLocalEvent(uid, new PointLightUpdateEvent());
         }
 
         private void HandleRemove(EntityUid uid, PointLightComponent component, ComponentRemove args)
         {
-            var map = EntityManager.GetComponent<TransformComponent>(uid).MapID;
-            // TODO: Just make this update the tree directly and not allocate
-            if (map != MapId.Nullspace)
+            if (Transform(uid).MapID != MapId.Nullspace)
             {
-                EntityManager.EventBus.RaiseEvent(EventSource.Local,
-                    new RenderTreeRemoveLightEvent(component, map));
+                _renderingTreeSystem.ClearLight(component);
             }
         }
 

Robust.Client/GameObjects/EntitySystems/RenderingTreeSystem.cs

@@ -70,21 +70,19 @@ namespace Robust.Client.GameObjects
             UpdatesAfter.Add(typeof(TransformSystem));
             UpdatesAfter.Add(typeof(PhysicsSystem));
 
-            _mapManager.MapCreated += MapManagerOnMapCreated;
-            _mapManager.OnGridCreated += MapManagerOnGridCreated;
+            SubscribeLocalEvent<MapChangedEvent>(MapManagerOnMapCreated);
+
+            SubscribeLocalEvent<GridInitializeEvent>(MapManagerOnGridCreated);
 
             // Due to how recursion works, this must be done.
             SubscribeLocalEvent<MoveEvent>(AnythingMoved);
 
-            SubscribeLocalEvent<SpriteComponent, EntMapIdChangedMessage>(SpriteMapChanged);
             SubscribeLocalEvent<SpriteComponent, EntParentChangedMessage>(SpriteParentChanged);
             SubscribeLocalEvent<SpriteComponent, ComponentRemove>(RemoveSprite);
             SubscribeLocalEvent<SpriteComponent, SpriteUpdateEvent>(HandleSpriteUpdate);
 
-            SubscribeLocalEvent<PointLightComponent, EntMapIdChangedMessage>(LightMapChanged);
             SubscribeLocalEvent<PointLightComponent, EntParentChangedMessage>(LightParentChanged);
             SubscribeLocalEvent<PointLightComponent, PointLightRadiusChangedEvent>(PointLightRadiusChanged);
-            SubscribeLocalEvent<PointLightComponent, RenderTreeRemoveLightEvent>(RemoveLight);
             SubscribeLocalEvent<PointLightComponent, PointLightUpdateEvent>(HandleLightUpdate);
 
             SubscribeLocalEvent<RenderingTreeComponent, ComponentInit>(OnTreeInit);
@@ -114,10 +112,18 @@ namespace Robust.Client.GameObjects
 
         private void AnythingMoved(ref MoveEvent args)
         {
-            AnythingMovedSubHandler(args.Sender);
+            var pointQuery = EntityManager.GetEntityQuery<PointLightComponent>();
+            var spriteQuery = EntityManager.GetEntityQuery<SpriteComponent>();
+            var xformQuery = EntityManager.GetEntityQuery<TransformComponent>();
+
+            AnythingMovedSubHandler(args.Sender, xformQuery, pointQuery, spriteQuery);
         }
 
-        private void AnythingMovedSubHandler(EntityUid uid, TransformComponent? xform = null)
+        private void AnythingMovedSubHandler(
+            EntityUid uid,
+            EntityQuery<TransformComponent> xformQuery,
+            EntityQuery<PointLightComponent> pointQuery,
+            EntityQuery<SpriteComponent> spriteQuery)
         {
             // To avoid doing redundant updates (and we don't need to update a grid's children ever)
             if (!_checkedChildren.Add(uid) || EntityManager.HasComponent<RenderingTreeComponent>(uid)) return;
@@ -126,17 +132,19 @@ namespace Robust.Client.GameObjects
             // WHATEVER YOU DO, DON'T REPLACE THIS WITH SPAMMING EVENTS UNLESS YOU HAVE A GUARANTEE IT WON'T LAG THE GC.
             // (Struct-based events ok though)
             // Ironically this was lagging the GC lolz
-            if (EntityManager.TryGetComponent(uid, out SpriteComponent? sprite))
+            if (spriteQuery.TryGetComponent(uid, out var sprite))
                 QueueSpriteUpdate(sprite);
 
-            if (EntityManager.TryGetComponent(uid, out PointLightComponent? light))
+            if (pointQuery.TryGetComponent(uid, out var light))
                 QueueLightUpdate(light);
 
-            if (!Resolve(uid, ref xform)) return;
+            if (!xformQuery.TryGetComponent(uid, out var xform)) return;
 
-            foreach (var child in xform.ChildEntities)
+            var childEnumerator = xform.ChildEnumerator;
+
+            while (childEnumerator.MoveNext(out var child))
             {
-                AnythingMovedSubHandler(child);
+                AnythingMovedSubHandler(child.Value, xformQuery, pointQuery, spriteQuery);
             }
         }
 
@@ -146,10 +154,6 @@ namespace Robust.Client.GameObjects
         // Otherwise these will still have their past MapId and that's all we need..
 
         #region SpriteHandlers
-        private void SpriteMapChanged(EntityUid uid, SpriteComponent component, EntMapIdChangedMessage args)
-        {
-            QueueSpriteUpdate(component);
-        }
 
         private void SpriteParentChanged(EntityUid uid, SpriteComponent component, ref EntParentChangedMessage args)
         {
@@ -179,10 +183,6 @@ namespace Robust.Client.GameObjects
         #endregion
 
         #region LightHandlers
-        private void LightMapChanged(EntityUid uid, PointLightComponent component, EntMapIdChangedMessage args)
-        {
-            QueueLightUpdate(component);
-        }
 
         private void LightParentChanged(EntityUid uid, PointLightComponent component, ref EntParentChangedMessage args)
         {
@@ -194,12 +194,7 @@ namespace Robust.Client.GameObjects
             QueueLightUpdate(component);
         }
 
-        private void RemoveLight(EntityUid uid, PointLightComponent component, RenderTreeRemoveLightEvent args)
-        {
-            ClearLight(component);
-        }
-
-        private void ClearLight(PointLightComponent component)
+        public void ClearLight(PointLightComponent component)
         {
             if (component.RenderTree == null) return;
 
@@ -216,13 +211,6 @@ namespace Robust.Client.GameObjects
         }
         #endregion
 
-        public override void Shutdown()
-        {
-            base.Shutdown();
-            _mapManager.MapCreated -= MapManagerOnMapCreated;
-            _mapManager.OnGridCreated -= MapManagerOnGridCreated;
-        }
-
         private void OnTreeRemove(EntityUid uid, RenderingTreeComponent component, ComponentRemove args)
         {
             foreach (var sprite in component.SpriteTree)
@@ -239,9 +227,9 @@ namespace Robust.Client.GameObjects
             component.LightTree.Clear();
         }
 
-        private void MapManagerOnMapCreated(object? sender, MapEventArgs e)
+        private void MapManagerOnMapCreated(MapChangedEvent e)
         {
-            if (e.Map == MapId.Nullspace)
+            if (e.Destroyed || e.Map == MapId.Nullspace)
             {
                 return;
             }
@@ -249,28 +237,26 @@ namespace Robust.Client.GameObjects
             EntityManager.EnsureComponent<RenderingTreeComponent>(_mapManager.GetMapEntityId(e.Map));
         }
 
-        private void MapManagerOnGridCreated(MapId mapId, GridId gridId)
+        private void MapManagerOnGridCreated(GridInitializeEvent ev)
         {
-            EntityManager.EnsureComponent<RenderingTreeComponent>(_mapManager.GetGrid(gridId).GridEntityId);
+            EntityManager.EnsureComponent<RenderingTreeComponent>(_mapManager.GetGrid(ev.GridId).GridEntityId);
         }
 
-        // TODO: Pass in TransformComponent directly: mainly interested in getting this shit working atm.
-        private RenderingTreeComponent? GetRenderTree(EntityUid entity)
+        private RenderingTreeComponent? GetRenderTree(EntityUid entity, EntityQuery<TransformComponent> xforms)
         {
+            var lookups = EntityManager.GetEntityQuery<RenderingTreeComponent>();
+
             if (!EntityManager.EntityExists(entity) ||
-                !EntityManager.TryGetComponent(entity, out TransformComponent? xform) ||
+                !xforms.TryGetComponent(entity, out var xform) ||
                 xform.MapID == MapId.Nullspace ||
-                EntityManager.HasComponent<RenderingTreeComponent>(entity)) return null;
+                lookups.HasComponent(entity)) return null;
 
             var parent = xform.ParentUid;
 
-            while (true)
+            while (parent.IsValid())
             {
-                if (!parent.IsValid())
-                    break;
-
-                if (EntityManager.TryGetComponent(parent, out RenderingTreeComponent? comp)) return comp;
-                parent = EntityManager.GetComponent<TransformComponent>(parent).ParentUid;
+                if (lookups.TryGetComponent(parent, out var comp)) return comp;
+                parent = xforms.GetComponent(parent).ParentUid;
             }
 
             return null;
@@ -285,6 +271,8 @@ namespace Robust.Client.GameObjects
         {
             _checkedChildren.Clear();
 
+            var xforms = EntityManager.GetEntityQuery<TransformComponent>();
+
             foreach (var sprite in _spriteQueue)
             {
                 sprite.TreeUpdateQueued = false;
@@ -295,9 +283,9 @@ namespace Robust.Client.GameObjects
                 }
 
                 var oldMapTree = sprite.RenderTree;
-                var newMapTree = GetRenderTree(sprite.Owner);
+                var newMapTree = GetRenderTree(sprite.Owner, xforms);
                 // TODO: Temp PVS guard
-                var xform = EntityManager.GetComponent<TransformComponent>(sprite.Owner);
+                var xform = xforms.GetComponent(sprite.Owner);
                 var (worldPos, worldRot) = xform.GetWorldPositionRotation();
 
                 if (float.IsNaN(worldPos.X) || float.IsNaN(worldPos.Y))
@@ -306,7 +294,7 @@ namespace Robust.Client.GameObjects
                     continue;
                 }
 
-                var aabb = SpriteAabbFunc(sprite, worldPos, worldRot);
+                var aabb = SpriteAabbFunc(sprite, worldPos, worldRot, xforms);
 
                 // If we're on a new map then clear the old one.
                 if (oldMapTree != newMapTree)
@@ -333,9 +321,9 @@ namespace Robust.Client.GameObjects
                 }
 
                 var oldMapTree = light.RenderTree;
-                var newMapTree = GetRenderTree(light.Owner);
+                var newMapTree = GetRenderTree(light.Owner, xforms);
                 // TODO: Temp PVS guard
-                var worldPos = EntityManager.GetComponent<TransformComponent>(light.Owner).WorldPosition;
+                var worldPos = xforms.GetComponent(light.Owner).WorldPosition;
 
                 if (float.IsNaN(worldPos.X) || float.IsNaN(worldPos.Y))
                 {
@@ -350,7 +338,7 @@ namespace Robust.Client.GameObjects
                     Logger.WarningS(LoggerSawmill, $"Light radius for {light.Owner} set above max radius of {MaxLightRadius}. This may lead to pop-in.");
                 }
 
-                var aabb = LightAabbFunc(light, worldPos);
+                var aabb = LightAabbFunc(light, worldPos, xforms);
 
                 // If we're on a new map then clear the old one.
                 if (oldMapTree != newMapTree)
@@ -372,82 +360,41 @@ namespace Robust.Client.GameObjects
 
         private Box2 SpriteAabbFunc(in SpriteComponent value)
         {
-            var xform = EntityManager.GetComponent<TransformComponent>(value.Owner);
+            var xforms = EntityManager.GetEntityQuery<TransformComponent>();
+            var xform = xforms.GetComponent(value.Owner);
             var (worldPos, worldRot) = xform.GetWorldPositionRotation();
-            var bounds = new Box2Rotated(value.CalculateBoundingBox(worldPos), worldRot, worldPos);
-            var tree = GetRenderTree(value.Owner);
 
-            if (tree == null)
-            {
-                return bounds.CalcBoundingBox();
-            }
-            else
-            {
-                return EntityManager.GetComponent<TransformComponent>(tree.Owner).InvWorldMatrix.TransformBox(bounds);
-            }
+            return SpriteAabbFunc(value, worldPos, worldRot, xforms);
         }
 
         private Box2 LightAabbFunc(in PointLightComponent value)
         {
-            var worldPos = EntityManager.GetComponent<TransformComponent>(value.Owner).WorldPosition;
-            var tree = GetRenderTree(value.Owner);
+            var xforms = EntityManager.GetEntityQuery<TransformComponent>();
+
+            var worldPos = xforms.GetComponent(value.Owner).WorldPosition;
+            var tree = GetRenderTree(value.Owner, xforms);
             var boxSize = value.Radius * 2;
 
-            Vector2 localPos;
-            if (tree == null)
-            {
-                localPos = worldPos;
-            }
-            else
-            {
-                // TODO: Need a way to just cache this InvWorldMatrix
-                localPos = EntityManager.GetComponent<TransformComponent>(tree.Owner).InvWorldMatrix.Transform(worldPos);
-            }
+            var localPos = tree == null ? worldPos : xforms.GetComponent(tree.Owner).InvWorldMatrix.Transform(worldPos);
             return Box2.CenteredAround(localPos, (boxSize, boxSize));
         }
 
-        private Box2 SpriteAabbFunc(SpriteComponent value, Vector2 worldPos, Angle worldRot)
+        private Box2 SpriteAabbFunc(SpriteComponent value, Vector2 worldPos, Angle worldRot, EntityQuery<TransformComponent> xforms)
         {
-            var bounds = new Box2Rotated(value.CalculateBoundingBox(worldPos), worldRot, worldPos);
-            var tree = GetRenderTree(value.Owner);
+            var bounds = value.CalculateRotatedBoundingBox(worldPos, worldRot);
+            var tree = GetRenderTree(value.Owner, xforms);
 
-            if (tree == null)
-            {
-                return bounds.CalcBoundingBox();
-            }
-            else
-            {
-                return EntityManager.GetComponent<TransformComponent>(tree.Owner).InvWorldMatrix.TransformBox(bounds);
-            }
+            return tree == null ? bounds.CalcBoundingBox() : xforms.GetComponent(tree.Owner).InvWorldMatrix.TransformBox(bounds);
         }
 
-        private Box2 LightAabbFunc(PointLightComponent value, Vector2 worldPos)
+        private Box2 LightAabbFunc(PointLightComponent value, Vector2 worldPos, EntityQuery<TransformComponent> xforms)
         {
             // Lights are circles so don't need entity's rotation
-            var tree = GetRenderTree(value.Owner);
+            var tree = GetRenderTree(value.Owner, xforms);
             var boxSize = value.Radius * 2;
 
-            Vector2 localPos;
-            if (tree == null)
-            {
-                localPos = worldPos;
-            } else
-            {
-                localPos = EntityManager.GetComponent<TransformComponent>(tree.Owner).InvWorldMatrix.Transform(worldPos);
-            }
+            var localPos = tree == null ? worldPos : xforms.GetComponent(tree.Owner).InvWorldMatrix.Transform(worldPos);
             return Box2.CenteredAround(localPos, (boxSize, boxSize));
         }
     }
-
-    internal class RenderTreeRemoveLightEvent : EntityEventArgs
-    {
-        public RenderTreeRemoveLightEvent(PointLightComponent light, MapId map)
-        {
-            Light = light;
-            Map = map;
-        }
-
-        public PointLightComponent Light { get; }
-        public MapId Map { get; }
-    }
 }

Robust.Client/GameObjects/EntitySystems/SpriteSystem.Specifier.cs

@@ -0,0 +1,84 @@
+using System;
+using JetBrains.Annotations;
+using Robust.Client.Graphics;
+using Robust.Client.ResourceManagement;
+using Robust.Client.Utility;
+using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Log;
+using Robust.Shared.Map;
+using Robust.Shared.Prototypes;
+using Robust.Shared.Utility;
+
+namespace Robust.Client.GameObjects;
+
+public sealed partial class SpriteSystem
+{
+    [Dependency] private readonly IPrototypeManager _proto = default!;
+    [Dependency] private readonly IResourceCache _resourceCache = default!;
+
+    [Pure]
+    public Texture Frame0(SpriteSpecifier specifier)
+    {
+        return RsiStateLike(specifier).Default;
+    }
+
+    [Pure]
+    public IRsiStateLike RsiStateLike(SpriteSpecifier specifier)
+    {
+        switch (specifier)
+        {
+            case SpriteSpecifier.Texture tex:
+                return tex.GetTexture(_resourceCache);
+
+            case SpriteSpecifier.Rsi rsi:
+                return GetState(rsi);
+
+            case SpriteSpecifier.EntityPrototype prototypeIcon:
+                if (!_proto.TryIndex<EntityPrototype>(prototypeIcon.EntityPrototypeId, out var prototype))
+                {
+                    Logger.Error("Failed to load PrototypeIcon {0}", prototypeIcon.EntityPrototypeId);
+                    return SpriteComponent.GetFallbackState(_resourceCache);
+                }
+
+                return SpriteComponent.GetPrototypeIcon(prototype, _resourceCache);
+
+            default:
+                throw new NotSupportedException();
+        }
+    }
+
+    [Pure]
+    public IRsiStateLike GetPrototypeIcon(EntityPrototype prototype, IResourceCache resourceCache)
+    {
+        var icon = IconComponent.GetPrototypeIcon(prototype, _resourceCache);
+        if (icon != null) return icon;
+
+        if (!prototype.Components.ContainsKey("Sprite"))
+        {
+            return SpriteComponent.GetFallbackState(resourceCache);
+        }
+
+        var dummy = Spawn(prototype.ID, MapCoordinates.Nullspace);
+        var spriteComponent = EnsureComp<SpriteComponent>(dummy);
+        var result = spriteComponent.Icon ?? SpriteComponent.GetFallbackState(resourceCache);
+        Del(dummy);
+
+        return result;
+    }
+
+    [Pure]
+    public RSI.State GetState(SpriteSpecifier.Rsi rsiSpecifier)
+    {
+        if (_resourceCache.TryGetResource<RSIResource>(
+                SharedSpriteComponent.TextureRoot / rsiSpecifier.RsiPath,
+                out var theRsi) &&
+            theRsi.RSI.TryGetState(rsiSpecifier.RsiState, out var state))
+        {
+            return state;
+        }
+
+        Logger.Error("Failed to load RSI {0}", rsiSpecifier.RsiPath);
+        return SpriteComponent.GetFallbackState(_resourceCache);
+    }
+}

Robust.Client/GameObjects/EntitySystems/SpriteSystem.cs

@@ -11,7 +11,7 @@ namespace Robust.Client.GameObjects
     /// Updates the layer animation for every visible sprite.
     /// </summary>
     [UsedImplicitly]
-    public class SpriteSystem : EntitySystem
+    public sealed partial class SpriteSystem : EntitySystem
     {
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly RenderingTreeSystem _treeSystem = default!;
@@ -53,9 +53,11 @@ namespace Robust.Client.GameObjects
                 return;
             }
 
+            var xforms = EntityManager.GetEntityQuery<TransformComponent>();
+
             foreach (var comp in _treeSystem.GetRenderTrees(currentMap, pvsBounds))
             {
-                var bounds = EntityManager.GetComponent<TransformComponent>(comp.Owner).InvWorldMatrix.TransformBox(pvsBounds);
+                var bounds = xforms.GetComponent(comp.Owner).InvWorldMatrix.TransformBox(pvsBounds);
 
                 comp.SpriteTree.QueryAabb(ref frameTime, (ref float state, in SpriteComponent value) =>
                 {

Robust.Client/GameObjects/EntitySystems/VelocityDebugSystem.cs

@@ -8,7 +8,7 @@ using Robust.Shared.Maths;
 
 namespace Robust.Client.GameObjects
 {
-    public class VelocityDebugSystem : EntitySystem
+    public sealed class VelocityDebugSystem : EntitySystem
     {
         [Dependency] private readonly IEyeManager _eyeManager = default!;
         [Dependency] private readonly IPlayerManager _playerManager = default!;