Version: 220.2.2

(cherry picked from commit 025d90d281)
(cherry picked from commit 799702b814)
(cherry picked from commit 4600ee8e5788891f1b610e2d5141fb4e1228d323)

.github/workflows/build-test.yml

@@ -27,7 +27,8 @@ jobs:
       run: dotnet restore
     - name: Build
       run: dotnet build --no-restore /p:WarningsAsErrors=nullable
-    - name: Test Engine
+    - name: Robust.UnitTesting
       run: dotnet test --no-build Robust.UnitTesting/Robust.UnitTesting.csproj -- NUnit.ConsoleOut=0
-
+    - name: Robust.Analyzers.Tests
+      run: dotnet test --no-build Robust.Analyzers.Tests/Robust.Analyzers.Tests.csproj -- NUnit.ConsoleOut=0
 

.github/workflows/publish-client.yml

@@ -33,10 +33,10 @@ jobs:
         mkdir "release/${{ steps.parse_version.outputs.version }}"
         mv release/*.zip "release/${{ steps.parse_version.outputs.version }}"
 
-    - name: Upload files to centcomm
+    - name: Upload files to Suns
       uses: appleboy/scp-action@master
       with:
-        host: centcomm.spacestation14.io
+        host: suns.spacestation14.com
         username: robust-build-push
         key: ${{ secrets.CENTCOMM_ROBUST_BUILDS_PUSH_KEY }}
         source: "release/${{ steps.parse_version.outputs.version }}"
@@ -46,7 +46,7 @@ jobs:
     - name: Update manifest JSON
       uses: appleboy/ssh-action@master
       with:
-        host: centcomm.spacestation14.io
+        host: suns.spacestation14.com
         username: robust-build-push
         key: ${{ secrets.CENTCOMM_ROBUST_BUILDS_PUSH_KEY }}
         script: /home/robust-build-push/push.ps1 ${{ steps.parse_version.outputs.version }}

Directory.Packages.props

@@ -1,4 +1,14 @@
 <Project>
+  <PropertyGroup>
+    <!--
+    We actually set ManagePackageVersionsCentrally manually in another import file.
+    Since .NET SDK 8.0.300, ManagePackageVersionsCentrally is automatically set if Directory.Packages.props exists.
+    https://github.com/NuGet/NuGet.Client/pull/5572
+    We actively negate this here, as we have some packages in tree we don't want such automatic behavior for.
+    We use Directory.Build.props to get copy the state *after* our MSBuild config but before Nuget's config.
+    -->
+    <ManagePackageVersionsCentrally />
+  </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="BenchmarkDotNet" Version="0.13.12" />
     <PackageVersion Include="DiscordRichPresence" Version="1.2.1.24" />
@@ -45,7 +55,7 @@
     <PackageVersion Include="Serilog" Version="3.1.1" />
     <PackageVersion Include="Serilog.Sinks.Loki" Version="4.0.0-beta3" />
     <PackageVersion Include="SharpZstd.Interop" Version="1.5.2-beta2" />
-    <PackageVersion Include="SixLabors.ImageSharp" Version="3.1.3" />
+    <PackageVersion Include="SixLabors.ImageSharp" Version="3.1.5" />
     <PackageVersion Include="SpaceWizards.HttpListener" Version="0.1.0" />
     <PackageVersion Include="SpaceWizards.NFluidsynth" Version="0.1.1" />
     <PackageVersion Include="SpaceWizards.SharpFont" Version="1.0.2" />

MSBuild/Robust.Engine.Version.props

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

RELEASE-NOTES.md

@@ -54,6 +54,166 @@ END TEMPLATE-->
 *None yet*
 
 
+## 220.2.2
+
+
+## 220.2.1
+
+
+## 220.2.0
+
+### New features
+
+* RSIs can now specify load parameters, mimicking the ones from `.png.yml`. Currently only disabling sRGB is supported.
+* Added a second UV channel to Clyde's vertex format. On regular batched sprite draws, this goes 0 -> 1 across the sprite quad.
+* Added a new `CopyToShaderParameters` system for `SpriteComponent` layers.
+
+
+## 220.1.0
+
+### Bugfixes
+
+* Fix client-side replay exceptions due to dropped states when recording.
+
+### Other
+
+* Remove IP + HWId from ViewVariables.
+* Close BUIs upon disconnect.
+
+
+## 220.0.0
+
+### Breaking changes
+
+* Refactor UserInterfaceSystem. 
+  - The API has been significantly cleaned up and standardised, most noticeably callers don't need to worry about TryGetUi and can rely on either HasUi, SetUiState, CloseUi, or OpenUi to handle their code as appropriate.
+  - Interface data is now stored via key rather than as a flat list which is a breaking change for YAML.
+  - BoundUserInterfaces can now be completely handled via Shared code. Existing Server-side callers will behave similarly to before.
+  - BoundUserInterfaces now properly close in many more situations, additionally they are now attached to the entity so reconnecting can re-open them and they can be serialized properly.
+
+
+## 219.2.0
+
+### New features
+
+* Add SetMapCoordinates to TransformSystem.
+* Improve YAML Linter and validation of static fields.
+
+### Bugfixes
+
+* Fix DebugCoordsPanel freezing when hovering a control.
+
+### Other
+
+* Optimise physics networking to not dirty every tick of movement.
+
+
+## 219.1.3
+
+### Bugfixes
+
+* Fix map-loader not pausing pre-init maps when not actively overwriting an existing map.
+
+
+## 219.1.2
+
+### Bugfixes
+
+* Fix map-loader not map-initialising grids when loading into a post-init map.
+
+
+## 219.1.1
+
+### Bugfixes
+
+* Fix map-loader not map-initialising maps when overwriting a post-init map.
+
+
+## 219.1.0
+
+### New features
+
+* Added a new optional arguments to various entity spawning methods, including a new argument to set the entity's rotation.
+
+### Bugfixes
+
+* Fixes map initialisation not always initialising all entities on a map.
+
+### Other
+
+* The default value of the `auth.mode` cvar has changed
+
+
+## 219.0.0
+
+### Breaking changes
+
+* Move most IMapManager functionality to SharedMapSystem.
+
+
+## 218.2.0
+
+### New features
+
+* Control layout properties such as `Margin` can now be set via style sheets.
+* Expose worldposition in SpriteComponent.Render
+* Network audio entity Play/Pause/Stop states and playback position.
+* Add `Disabled` functionality to `Slider` control.
+
+
+## 218.1.0
+
+### New features
+
+* Add IEquatable.Equals to the sandbox.
+* Enable roslyn extensions tests in CI.
+* Add a VerticalTabContainer control to match the horizontal one.
+
+### Bugfixes
+
+* Fix divison remainder issue for Colors, fixing purples.
+
+### Other
+
+* Default hub address (`hub.hub_urls`) has been changed to `https://hub.spacestation14.com/`.
+
+
+## 218.0.0
+
+### Breaking changes
+
+* `Robust.Shared.Configuration.EnvironmentVariables` is now internal and no longer usable by content.
+
+### New features
+
+* Add TryGetRandom to EntityManager to get a random entity with the specified component and TryGetRandom to IPrototypeManager to return a random prototype of the specified type.
+* Add CopyData to AppearanceSystem.
+* Update UI themes on prototype reloads.
+* Allow scaling the line height of a RichTextLabel.
+* You can now specify CVar overrides via environment variable with the `ROBUST_CVAR_*` prefix. For example `ROBUST_CVAR_game__hostname=foobar` would set the appropriate CVar. Double underscores in the environment variable name are replaced with ".".
+* Added non-generic variant of `GetCVar` to `IConfigurationManager`.
+* Add type tracking to FieldNotFoundErrorNode for serialization.
+* Distance between lines of a `RichTextLabel` can now be modified with `LineHeightScale`.
+* UI theme prototypes are now updated when reloaded.
+* New `RA0025` analyzer diagnostic warns for manual assignment to `[Dependency]` fields.
+
+### Bugfixes
+
+* Request headers in `IStatusHandlerContext` are now case-insensitive.
+* SetWorldPosition rotation now more closely aligns with prior behavior.
+* Fix exception when inspecting elements in some cases.
+* Fix HTTP errors on watchdog ping not being reported.
+
+### Other
+
+* Add an analyzer for redundantly assigning to dependency fields.
+
+### Internal
+
+* Remove redundant Exists checks in ContainerSystem.
+* Improve logging on watchdog pings.
+
+
 ## 217.2.1
 
 ### Bugfixes
@@ -69,7 +229,7 @@ END TEMPLATE-->
 
 ### New features
 
-* Added `AddComponents` and `RemoveComponents` methods to EntityManager that handle EntityPrototype / ComponentRegistry bulk component changes. 
+* Added `AddComponents` and `RemoveComponents` methods to EntityManager that handle EntityPrototype / ComponentRegistry bulk component changes.
 * Add double-clicking to LineEdit.
 
 ### Bugfixes

Robust.Analyzers.Tests/AccessAnalyzer_Test.cs

@@ -20,11 +20,16 @@ public sealed class AccessAnalyzer_Test
         {
             TestState =
             {
-                AdditionalReferences = { typeof(AccessAnalyzer).Assembly },
                 Sources = { code }
             },
         };
 
+        TestHelper.AddEmbeddedSources(
+            test.TestState,
+            "Robust.Shared.Analyzers.AccessAttribute.cs",
+            "Robust.Shared.Analyzers.AccessPermissions.cs"
+        );
+
         // ExpectedDiagnostics cannot be set, so we need to AddRange here...
         test.TestState.ExpectedDiagnostics.AddRange(expected);
 

Robust.Analyzers.Tests/DependencyAssignAnalyzerTest.cs

@@ -0,0 +1,58 @@
+using System.Threading.Tasks;
+using Microsoft.CodeAnalysis.CSharp.Testing;
+using Microsoft.CodeAnalysis.Testing;
+using Microsoft.CodeAnalysis.Testing.Verifiers;
+using NUnit.Framework;
+using VerifyCS =
+    Microsoft.CodeAnalysis.CSharp.Testing.NUnit.AnalyzerVerifier<Robust.Analyzers.DependencyAssignAnalyzer>;
+
+namespace Robust.Analyzers.Tests;
+
+[Parallelizable(ParallelScope.All | ParallelScope.Fixtures)]
+[TestFixture]
+public sealed class DependencyAssignAnalyzerTest
+{
+    private static Task Verifier(string code, params DiagnosticResult[] expected)
+    {
+        var test = new CSharpAnalyzerTest<DependencyAssignAnalyzer, NUnitVerifier>()
+        {
+            TestState =
+            {
+                Sources = { code }
+            },
+        };
+
+        TestHelper.AddEmbeddedSources(
+            test.TestState,
+            "Robust.Shared.IoC.DependencyAttribute.cs"
+        );
+
+        // ExpectedDiagnostics cannot be set, so we need to AddRange here...
+        test.TestState.ExpectedDiagnostics.AddRange(expected);
+
+        return test.RunAsync();
+    }
+
+    [Test]
+    public async Task Test()
+    {
+        const string code = """
+            using Robust.Shared.IoC;
+
+            public sealed class Foo
+            {
+                [Dependency]
+                private object? Field;
+
+                public Foo()
+                {
+                    Field = "A";
+                }
+            }
+            """;
+
+        await Verifier(code,
+            // /0/Test0.cs(10,9): warning RA0025: Tried to assign to [Dependency] field 'Field'. Remove [Dependency] or inject it via field injection instead.
+            VerifyCS.Diagnostic().WithSpan(10, 9, 10, 20).WithArguments("Field"));
+    }
+}

Robust.Analyzers.Tests/Robust.Analyzers.Tests.csproj

@@ -6,6 +6,13 @@
   <Import Project="..\MSBuild\Robust.Properties.targets"/>
   <Import Project="..\MSBuild\Robust.Engine.props"/>
 
+  <!-- Engine source files needed to make the tests work -->
+  <ItemGroup>
+    <EmbeddedResource Include="..\Robust.Shared\Analyzers\AccessAttribute.cs" LogicalName="Robust.Shared.Analyzers.AccessAttribute.cs" LinkBase="Implementations" />
+    <EmbeddedResource Include="..\Robust.Shared\Analyzers\AccessPermissions.cs" LogicalName="Robust.Shared.Analyzers.AccessPermissions.cs" LinkBase="Implementations" />
+    <EmbeddedResource Include="..\Robust.Shared\IoC\DependencyAttribute.cs" LogicalName="Robust.Shared.IoC.DependencyAttribute.cs" LinkBase="Implementations" />
+  </ItemGroup>
+
   <PropertyGroup>
     <IsPackable>false</IsPackable>
   </PropertyGroup>

Robust.Analyzers.Tests/TestHelper.cs

@@ -0,0 +1,22 @@
+using System.Collections.Generic;
+using Microsoft.CodeAnalysis.Testing;
+using Microsoft.CodeAnalysis.Text;
+
+namespace Robust.Analyzers.Tests;
+
+public static class TestHelper
+{
+    public static void AddEmbeddedSources(SolutionState state, params string[] embeddedFiles)
+    {
+        AddEmbeddedSources(state, (IEnumerable<string>) embeddedFiles);
+    }
+
+    public static void AddEmbeddedSources(SolutionState state, IEnumerable<string> embeddedFiles)
+    {
+        foreach (var fileName in embeddedFiles)
+        {
+            using var stream = typeof(AccessAnalyzer_Test).Assembly.GetManifestResourceStream(fileName)!;
+            state.Sources.Add((fileName, SourceText.From(stream)));
+        }
+    }
+}

Robust.Analyzers/DependencyAssignAnalyzer.cs

@@ -0,0 +1,61 @@
+using System.Collections.Immutable;
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.Diagnostics;
+using Microsoft.CodeAnalysis.Operations;
+using Robust.Roslyn.Shared;
+
+namespace Robust.Analyzers;
+
+[DiagnosticAnalyzer(LanguageNames.CSharp)]
+public sealed class DependencyAssignAnalyzer : DiagnosticAnalyzer
+{
+    private const string DependencyAttributeType = "Robust.Shared.IoC.DependencyAttribute";
+
+    private static readonly DiagnosticDescriptor Rule = new (
+        Diagnostics.IdDependencyFieldAssigned,
+        "Assignment to dependency field",
+        "Tried to assign to [Dependency] field '{0}'. Remove [Dependency] or inject it via field injection instead.",
+        "Usage",
+        DiagnosticSeverity.Warning,
+        true);
+
+    public override ImmutableArray<DiagnosticDescriptor> SupportedDiagnostics => ImmutableArray.Create(Rule);
+
+    public override void Initialize(AnalysisContext context)
+    {
+        context.EnableConcurrentExecution();
+        context.ConfigureGeneratedCodeAnalysis(GeneratedCodeAnalysisFlags.None);
+        context.RegisterOperationAction(CheckAssignment, OperationKind.SimpleAssignment);
+    }
+
+    private static void CheckAssignment(OperationAnalysisContext context)
+    {
+        if (context.Operation is not ISimpleAssignmentOperation assignment)
+            return;
+
+        if (assignment.Target is not IFieldReferenceOperation fieldRef)
+            return;
+
+        var field = fieldRef.Field;
+        var attributes = field.GetAttributes();
+        if (attributes.Length == 0)
+            return;
+
+        var depAttribute = context.Compilation.GetTypeByMetadataName(DependencyAttributeType);
+        if (!HasAttribute(attributes, depAttribute))
+            return;
+
+        context.ReportDiagnostic(Diagnostic.Create(Rule, assignment.Syntax.GetLocation(), field.Name));
+    }
+
+    private static bool HasAttribute(ImmutableArray<AttributeData> attributes, ISymbol symbol)
+    {
+        foreach (var attribute in attributes)
+        {
+            if (SymbolEqualityComparer.Default.Equals(attribute.AttributeClass, symbol))
+                return true;
+        }
+
+        return false;
+    }
+}

Robust.Analyzers/Robust.Analyzers.csproj

@@ -2,24 +2,29 @@
 
   <ItemGroup>
     <!-- Needed for NotNullableFlagAnalyzer. -->
-    <Compile Include="..\Robust.Shared\Analyzers\NotNullableFlagAttribute.cs" />
+    <Compile Include="..\Robust.Shared\Analyzers\NotNullableFlagAttribute.cs" LinkBase="Implementations" />
   </ItemGroup>
 
   <ItemGroup>
     <!-- Needed for FriendAnalyzer. -->
-    <Compile Include="..\Robust.Shared\Analyzers\AccessAttribute.cs" />
-    <Compile Include="..\Robust.Shared\Analyzers\AccessPermissions.cs" />
+    <Compile Include="..\Robust.Shared\Analyzers\AccessAttribute.cs" LinkBase="Implementations" />
+    <Compile Include="..\Robust.Shared\Analyzers\AccessPermissions.cs" LinkBase="Implementations" />
   </ItemGroup>
 
   <ItemGroup>
     <!-- Needed for PreferGenericVariantAnalyzer. -->
-    <Compile Include="..\Robust.Shared\Analyzers\PreferGenericVariantAttribute.cs" />
+    <Compile Include="..\Robust.Shared\Analyzers\PreferGenericVariantAttribute.cs" LinkBase="Implementations" />
   </ItemGroup>
 
   <Import Project="../Robust.Roslyn.Shared/Robust.Roslyn.Shared.props" />
 
   <PropertyGroup>
     <Nullable>disable</Nullable>
+    <!--
+    Rider seems to get really confused with hot reload if we directly compile in the above-linked classes.
+    As such, they have an #if to change their namespace in this project.
+    -->
+    <DefineConstants>$(DefineConstants);ROBUST_ANALYZERS_IMPL</DefineConstants>
   </PropertyGroup>
 
 </Project>

Robust.Benchmarks/EntityManager/AddRemoveComponentBenchmark.cs

@@ -26,9 +26,8 @@ public partial class AddRemoveComponentBenchmark
             .InitializeInstance();
 
         _entityManager = _simulation.Resolve<IEntityManager>();
-
-        var coords = new MapCoordinates(0, 0, new MapId(1));
-        _simulation.AddMap(coords.MapId);
+        var map = _simulation.CreateMap().Uid;
+        var coords = new EntityCoordinates(map, default);
 
         for (var i = 0; i < N; i++)
         {

Robust.Benchmarks/EntityManager/ComponentIteratorBenchmark.cs

@@ -29,8 +29,8 @@ public partial class ComponentIteratorBenchmark
 
         Comps = new A[N+2];
 
-        var coords = new MapCoordinates(0, 0, new MapId(1));
-        _simulation.AddMap(coords.MapId);
+        var map = _simulation.CreateMap().MapId;
+        var coords = new MapCoordinates(default, map);
 
         for (var i = 0; i < N; i++)
         {

Robust.Benchmarks/EntityManager/GetComponentBenchmark.cs

@@ -31,8 +31,8 @@ public partial class GetComponentBenchmark
 
         Comps = new A[N+2];
 
-        var coords = new MapCoordinates(0, 0, new MapId(1));
-        _simulation.AddMap(coords.MapId);
+        var map = _simulation.CreateMap().Uid;
+        var coords = new EntityCoordinates(map, default);
 
         for (var i = 0; i < N; i++)
         {

Robust.Benchmarks/EntityManager/SpawnDeleteEntityBenchmark.cs

@@ -29,10 +29,9 @@ public partial class SpawnDeleteEntityBenchmark
             .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);
+        var (map, mapId) = _simulation.CreateMap();
+        _mapCoords = new MapCoordinates(default, mapId);
+        _entCoords = new EntityCoordinates(map, 0, 0);
     }
 
     [Benchmark(Baseline = true)]

Robust.Benchmarks/Transform/RecursiveMoveBenchmark.cs

@@ -91,8 +91,7 @@ public class RecursiveMoveBenchmark : RobustIntegrationTest
         // Set up map and spawn player
         server.WaitPost(() =>
         {
-            var mapId = mapMan.CreateMap();
-            var map = mapMan.GetMapEntityId(mapId);
+            var map = server.ResolveDependency<SharedMapSystem>().CreateMap(out var mapId);
             var gridComp = mapMan.CreateGridEntity(mapId);
             var grid = gridComp.Owner;
             mapSys.SetTile(grid, gridComp, Vector2i.Zero, new Tile(1));

Robust.Client/Audio/AudioOverlay.cs

@@ -74,11 +74,13 @@ public sealed class AudioOverlay : Overlay
             output.Clear();
             output.AppendLine("Audio Source");
             output.AppendLine("Runtime:");
+            output.AppendLine($"- Distance: {_audio.GetAudioDistance(distance.Length()):0.00}");
             output.AppendLine($"- Occlusion: {posOcclusion:0.0000}");
             output.AppendLine("Params:");
+            output.AppendLine($"- RolloffFactor: {comp.RolloffFactor:0.0000}");
             output.AppendLine($"- Volume: {comp.Volume:0.0000}");
-            output.AppendLine($"- Reference distance: {comp.ReferenceDistance}");
-            output.AppendLine($"- Max distance: {comp.MaxDistance}");
+            output.AppendLine($"- Reference distance: {comp.ReferenceDistance:0.00}");
+            output.AppendLine($"- Max distance: {comp.MaxDistance:0.00}");
             var outputText = output.ToString().Trim();
             var dimensions = screenHandle.GetDimensions(_font, outputText, 1f);
             var buffer = new Vector2(3f, 3f);

Robust.Client/Audio/AudioSystem.cs

@@ -126,6 +126,33 @@ public sealed partial class AudioSystem : SharedAudioSystem
         {
             component.Source.SetAuxiliary(null);
         }
+
+        switch (component.State)
+        {
+            case AudioState.Playing:
+                component.StartPlaying();
+                break;
+            case AudioState.Paused:
+                component.Pause();
+                break;
+            case AudioState.Stopped:
+                component.StopPlaying();
+                component.PlaybackPosition = 0f;
+                break;
+        }
+
+        // If playback position changed then update it.
+        if (!string.IsNullOrEmpty(component.FileName))
+        {
+            var position = (float) ((component.PauseTime ?? Timing.CurTime) - component.AudioStart).TotalSeconds;
+            var currentPosition = component.Source.PlaybackPosition;
+            var diff = Math.Abs(position - currentPosition);
+
+            if (diff > 0.1f)
+            {
+                component.PlaybackPosition = position;
+            }
+        }
     }
 
     /// <summary>
@@ -361,7 +388,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
         var distance = delta.Length();
 
         // Out of range so just clip it for us.
-        if (distance > component.MaxDistance)
+        if (GetAudioDistance(distance) > component.MaxDistance)
         {
             // Still keeps the source playing, just with no volume.
             component.Gain = 0f;

Robust.Client/Audio/Sources/BaseAudioSource.cs

@@ -314,6 +314,8 @@ public abstract class BaseAudioSource : IAudioSource
         set
         {
             _checkDisposed();
+
+            value = MathF.Max(value, 0f);
             AL.Source(SourceHandle, ALSourcef.SecOffset, value);
             Master._checkAlError($"Tried to set invalid playback position of {value:0.00}");
         }

Robust.Client/BaseClient.cs

@@ -285,6 +285,7 @@ namespace Robust.Client
     /// <summary>
     ///     Enumeration of the run levels of the BaseClient.
     /// </summary>
+    /// <seealso cref="ClientRunLevelExt"/>
     public enum ClientRunLevel : byte
     {
         Error = 0,
@@ -315,6 +316,21 @@ namespace Robust.Client
         SinglePlayerGame,
     }
 
+    /// <summary>
+    /// Helper functions for working with <see cref="ClientRunLevel"/>.
+    /// </summary>
+    public static class ClientRunLevelExt
+    {
+        /// <summary>
+        /// Check if a <see cref="ClientRunLevel"/> is <see cref="ClientRunLevel.InGame"/>
+        /// or <see cref="ClientRunLevel.SinglePlayerGame"/>.
+        /// </summary>
+        public static bool IsInGameLike(this ClientRunLevel runLevel)
+        {
+            return runLevel is ClientRunLevel.InGame or ClientRunLevel.SinglePlayerGame;
+        }
+    }
+
     /// <summary>
     ///     Event arguments for when something changed with the player.
     /// </summary>

Robust.Client/Console/Commands/DumpMetadataMembersCommand.cs

@@ -11,7 +11,7 @@ namespace Robust.Client.Console.Commands
 
         public override void Execute(IConsoleShell shell, string argStr, string[] args)
         {
-            var type = Type.GetType(args[0]);
+            var type = GetType(args[0]);
 
             if (type == null)
             {
@@ -25,6 +25,17 @@ namespace Robust.Client.Console.Commands
                 shell.WriteLine(sig);
             }
         }
+
+        private Type? GetType(string name)
+        {
+            foreach (var assembly in AppDomain.CurrentDomain.GetAssemblies())
+            {
+                if (assembly.GetType(name) is { } type)
+                    return type;
+            }
+
+            return null;
+        }
     }
 #endif
 }

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

@@ -6,13 +6,12 @@ using System.Linq;
 using System.Numerics;
 using System.Text;
 using Robust.Client.Graphics;
+using Robust.Client.Graphics.Clyde;
 using Robust.Client.ResourceManagement;
 using Robust.Client.Utility;
-using Robust.Shared;
 using Robust.Shared.Animations;
 using Robust.Shared.ComponentTrees;
 using Robust.Shared.GameObjects;
-using Robust.Shared.Graphics;
 using Robust.Shared.Graphics.RSI;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
@@ -30,6 +29,7 @@ using static Robust.Client.ComponentTrees.SpriteTreeSystem;
 using DrawDepthTag = Robust.Shared.GameObjects.DrawDepth;
 using static Robust.Shared.Serialization.TypeSerializers.Implementations.SpriteSpecifierSerializer;
 using Direction = Robust.Shared.Maths.Direction;
+using Vector4 = Robust.Shared.Maths.Vector4;
 
 namespace Robust.Client.GameObjects
 {
@@ -772,15 +772,7 @@ namespace Robust.Client.GameObjects
             {
                 foreach (var keyString in layerDatum.MapKeys)
                 {
-                    object key;
-                    if (reflection.TryParseEnumReference(keyString, out var @enum))
-                    {
-                        key = @enum;
-                    }
-                    else
-                    {
-                        key = keyString;
-                    }
+                    var key = ParseKey(keyString);
 
                     if (LayerMap.TryGetValue(key, out var mappedIndex))
                     {
@@ -806,9 +798,30 @@ namespace Robust.Client.GameObjects
             // If neither state: nor texture: were provided we assume that they want a blank invisible layer.
             layer.Visible = layerDatum.Visible ?? layer.Visible;
 
+            if (layerDatum.CopyToShaderParameters is { } copyParameters)
+            {
+                layer.CopyToShaderParameters = new CopyToShaderParameters(ParseKey(copyParameters.LayerKey))
+                {
+                    ParameterTexture = copyParameters.ParameterTexture,
+                    ParameterUV = copyParameters.ParameterUV
+                };
+            }
+            else
+            {
+                layer.CopyToShaderParameters = null;
+            }
+
             RebuildBounds();
         }
 
+        private object ParseKey(string keyString)
+        {
+            if (reflection.TryParseEnumReference(keyString, out var @enum))
+                return @enum;
+
+            return keyString;
+        }
+
         public void LayerSetData(object layerKey, PrototypeLayerData data)
         {
             if (!LayerMapTryGet(layerKey, out var layer, true))
@@ -1237,9 +1250,9 @@ namespace Robust.Client.GameObjects
         public IEnumerable<ISpriteLayer> AllLayers => Layers;
 
         // Lobby SpriteView rendering path
-        public void Render(DrawingHandleWorld drawingHandle, Angle eyeRotation, Angle worldRotation, Direction? overrideDirection = null)
+        public void Render(DrawingHandleWorld drawingHandle, Angle eyeRotation, Angle worldRotation, Direction? overrideDirection = null, Vector2 position = default)
         {
-            RenderInternal(drawingHandle, eyeRotation, worldRotation, Vector2.Zero, overrideDirection);
+            RenderInternal(drawingHandle, eyeRotation, worldRotation, position, overrideDirection);
         }
 
         [DataField("noRot")] private bool _screenLock = false;
@@ -1637,6 +1650,9 @@ namespace Robust.Client.GameObjects
             [ViewVariables]
             public LayerRenderingStrategy RenderingStrategy = LayerRenderingStrategy.UseSpriteStrategy;
 
+            [ViewVariables(VVAccess.ReadWrite)]
+            public CopyToShaderParameters? CopyToShaderParameters;
+
             public Layer(SpriteComponent parent)
             {
                 _parent = parent;
@@ -2009,8 +2025,6 @@ namespace Robust.Client.GameObjects
 
                 // Set the drawing transform for this layer
                 GetLayerDrawMatrix(dir, out var layerMatrix);
-                Matrix3.Multiply(in layerMatrix, in spriteMatrix, out var transformMatrix);
-                drawingHandle.SetTransform(in transformMatrix);
 
                 // The direction used to draw the sprite can differ from the one that the angle would naively suggest,
                 // due to direction overrides or offsets.
@@ -2020,7 +2034,41 @@ namespace Robust.Client.GameObjects
 
                 // Get the correct directional texture from the state, and draw it!
                 var texture = GetRenderTexture(_actualState, dir);
-                RenderTexture(drawingHandle, texture);
+
+                if (CopyToShaderParameters == null)
+                {
+                    // Set the drawing transform for this layer
+                    Matrix3.Multiply(in layerMatrix, in spriteMatrix, out var transformMatrix);
+                    drawingHandle.SetTransform(in transformMatrix);
+
+                    RenderTexture(drawingHandle, texture);
+                }
+                else
+                {
+                    // Multiple atrocities to god being committed right here.
+                    var otherLayerIdx = _parent.LayerMap[CopyToShaderParameters.LayerKey!];
+                    var otherLayer = _parent.Layers[otherLayerIdx];
+                    if (otherLayer.Shader is not { } shader)
+                    {
+                        // No shader set apparently..?
+                        return;
+                    }
+
+                    if (!shader.Mutable)
+                        otherLayer.Shader = shader = shader.Duplicate();
+
+                    var clydeTexture = Clyde.RenderHandle.ExtractTexture(texture, null, out var csr);
+                    var sr = Clyde.RenderHandle.WorldTextureBoundsToUV(clydeTexture, csr);
+
+                    if (CopyToShaderParameters.ParameterTexture is { } paramTexture)
+                        shader.SetParameter(paramTexture, clydeTexture);
+
+                    if (CopyToShaderParameters.ParameterUV is { } paramUV)
+                    {
+                        var uv = new Vector4(sr.Left, sr.Bottom, sr.Right, sr.Top);
+                        shader.SetParameter(paramUV, uv);
+                    }
+                }
             }
 
             private void RenderTexture(DrawingHandleWorld drawingHandle, Texture texture)
@@ -2098,6 +2146,17 @@ namespace Robust.Client.GameObjects
             }
         }
 
+        /// <summary>
+        /// Instantiated version of <see cref="PrototypeCopyToShaderParameters"/>.
+        /// Has <see cref="LayerKey"/> actually resolved to a a real key.
+        /// </summary>
+        public sealed class CopyToShaderParameters(object layerKey)
+        {
+            public object LayerKey = layerKey;
+            public string? ParameterTexture;
+            public string? ParameterUV;
+        }
+
         void IAnimationProperties.SetAnimatableProperty(string name, object value)
         {
             if (!name.StartsWith("layer/"))

Robust.Client/GameObjects/EntitySystems/MapSystem.cs

@@ -1,12 +1,9 @@
 using Robust.Client.Graphics;
 using Robust.Client.Map;
-using Robust.Client.Physics;
 using Robust.Client.ResourceManagement;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
 using Robust.Shared.Map;
-using Robust.Shared.Map.Components;
-using Robust.Shared.Physics.Dynamics;
 
 namespace Robust.Client.GameObjects;
 
@@ -16,6 +13,17 @@ public sealed class MapSystem : SharedMapSystem
     [Dependency] private readonly IResourceCache _resource = default!;
     [Dependency] private readonly ITileDefinitionManager _tileDefinitionManager = default!;
 
+    protected override MapId GetNextMapId()
+    {
+        // Client-side map entities use negative map Ids to avoid conflict with server-side maps.
+        var id = new MapId(--LastMapId);
+        while (MapManager.MapExists(id))
+        {
+            id = new MapId(--LastMapId);
+        }
+        return id;
+    }
+
     public override void Initialize()
     {
         base.Initialize();
@@ -27,9 +35,4 @@ public sealed class MapSystem : SharedMapSystem
         base.Shutdown();
         _overlayManager.RemoveOverlay<TileEdgeOverlay>();
     }
-
-    protected override void OnMapAdd(EntityUid uid, MapComponent component, ComponentAdd args)
-    {
-        EnsureComp<PhysicsMapComponent>(uid);
-    }
 }

Robust.Client/GameObjects/EntitySystems/UserInterfaceSystem.cs

@@ -1,84 +1,8 @@
-using Robust.Client.Player;
 using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
-using Robust.Shared.Reflection;
-using System;
-using UserInterfaceComponent = Robust.Shared.GameObjects.UserInterfaceComponent;
 
-namespace Robust.Client.GameObjects
+namespace Robust.Client.GameObjects;
+
+public sealed class UserInterfaceSystem : SharedUserInterfaceSystem
 {
-    public sealed class UserInterfaceSystem : SharedUserInterfaceSystem
-    {
-        [Dependency] private readonly IDynamicTypeFactory _dynamicTypeFactory = default!;
-        [Dependency] private readonly IPlayerManager _playerManager = default!;
-        [Dependency] private readonly IReflectionManager _reflectionManager = default!;
 
-        public override void Initialize()
-        {
-            base.Initialize();
-
-            SubscribeNetworkEvent<BoundUIWrapMessage>(MessageReceived);
-        }
-
-        private void MessageReceived(BoundUIWrapMessage ev)
-        {
-            var uid = GetEntity(ev.Entity);
-
-            if (!TryComp<UserInterfaceComponent>(uid, out var cmp))
-                return;
-
-            var uiKey = ev.UiKey;
-            var message = ev.Message;
-            message.Session = _playerManager.LocalSession!;
-            message.Entity = GetNetEntity(uid);
-            message.UiKey = uiKey;
-
-            // Raise as object so the correct type is used.
-            RaiseLocalEvent(uid, (object)message, true);
-
-            switch (message)
-            {
-                case OpenBoundInterfaceMessage _:
-                    TryOpenUi(uid, uiKey, cmp);
-                    break;
-
-                case CloseBoundInterfaceMessage _:
-                    TryCloseUi(message.Session, uid, uiKey, remoteCall: true, uiComp: cmp);
-                    break;
-
-                default:
-                    if (cmp.OpenInterfaces.TryGetValue(uiKey, out var bui))
-                        bui.InternalReceiveMessage(message);
-
-                    break;
-            }
-        }
-
-        private bool TryOpenUi(EntityUid uid, Enum uiKey, UserInterfaceComponent? uiComp = null)
-        {
-            if (!Resolve(uid, ref uiComp))
-                return false;
-
-            if (uiComp.OpenInterfaces.ContainsKey(uiKey))
-                return false;
-
-            var data = uiComp.MappedInterfaceData[uiKey];
-
-            // TODO: This type should be cached, but I'm too lazy.
-            var type = _reflectionManager.LooseGetType(data.ClientType);
-            var boundInterface =
-                (BoundUserInterface) _dynamicTypeFactory.CreateInstance(type, new object[] {uid, uiKey});
-
-            boundInterface.Open();
-            uiComp.OpenInterfaces[uiKey] = boundInterface;
-
-            if (_playerManager.LocalSession is { } playerSession)
-            {
-                uiComp.Interfaces[uiKey]._subscribedSessions.Add(playerSession);
-                RaiseLocalEvent(uid, new BoundUIOpenedEvent(uiKey, uid, playerSession), true);
-            }
-
-            return true;
-        }
-    }
 }

Robust.Client/GameStates/ClientGameStateManager.cs

@@ -1138,7 +1138,7 @@ namespace Robust.Client.GameStates
                     if ((meta.Flags & MetaDataFlags.InContainer) != 0 &&
                         metas.TryGetComponent(xform.ParentUid, out var containerMeta) &&
                         (containerMeta.Flags & MetaDataFlags.Detached) == 0 &&
-                        containerSys.TryGetContainingContainer(xform.ParentUid, ent.Value, out container, null, true))
+                        containerSys.TryGetContainingContainer(xform.ParentUid, ent.Value, out container))
                     {
                         containerSys.Remove((ent.Value, xform, meta), container, false, true);
                     }
@@ -1329,23 +1329,8 @@ namespace Robust.Client.GameStates
 
             foreach (var (comp, cur, next) in _compStateWork.Values)
             {
-                try
-                {
-                    var handleState = new ComponentHandleState(cur, next);
-                    bus.RaiseComponentEvent(comp, ref handleState);
-                }
-#pragma warning disable CS0168 // Variable is declared but never used
-                catch (Exception e)
-#pragma warning restore CS0168 // Variable is declared but never used
-                {
-#if EXCEPTION_TOLERANCE
-                    _sawmill.Error($"Failed to apply comp state: entity={_entities.ToPrettyString(uid)}, comp={comp.GetType()}");
-                    _runtimeLog.LogException(e, $"{nameof(ClientGameStateManager)}.{nameof(HandleEntityState)}");
-#else
-                    _sawmill.Error($"Failed to apply comp state: entity={_entities.ToPrettyString(uid)}, comp={comp.GetType()}");
-                    throw;
-#endif
-                }
+                var handleState = new ComponentHandleState(cur, next);
+                bus.RaiseComponentEvent(comp, ref handleState);
             }
         }
 
@@ -1414,7 +1399,7 @@ namespace Robust.Client.GameStates
                     _entities.TryGetComponent(xform.ParentUid, out MetaDataComponent? containerMeta) &&
                     (containerMeta.Flags & MetaDataFlags.Detached) == 0)
                 {
-                    containerSys.TryGetContainingContainer(xform.ParentUid, uid, out container, null, true);
+                    containerSys.TryGetContainingContainer(xform.ParentUid, uid, out container);
                 }
 
                 _entities.EntitySysManager.GetEntitySystem<TransformSystem>().DetachParentToNull(uid, xform);

Robust.Client/Graphics/Clyde/Clyde.Constants.cs

@@ -6,7 +6,8 @@ namespace Robust.Client.Graphics.Clyde
         {
             ("aPos", 0),
             ("tCoord", 1),
-            ("modulate", 2)
+            ("tCoord2", 2),
+            ("modulate", 3)
         };
 
         private const int UniIModUV = 0;

Robust.Client/Graphics/Clyde/Clyde.GridRendering.cs

@@ -124,7 +124,7 @@ namespace Robust.Client.Graphics.Clyde
         {
             foreach (var (grid, chunks) in _mapChunkData)
             {
-                var gridComp = _mapManager.GetGridComp(grid);
+                var gridComp = _entityManager.GetComponent<MapGridComponent>(grid);
                 foreach (var (index, chunk) in chunks)
                 {
                     if (!chunk.Dirty || gridComp.Chunks.ContainsKey(index))

Robust.Client/Graphics/Clyde/Clyde.HLR.cs

@@ -251,10 +251,8 @@ namespace Robust.Client.Graphics.Clyde
         private void DrawEntities(Viewport viewport, Box2Rotated worldBounds, Box2 worldAABB, IEye eye)
         {
             var mapId = eye.Position.MapId;
-            if (mapId == MapId.Nullspace || !_mapManager.HasMapEntity(mapId))
-            {
+            if (mapId == MapId.Nullspace)
                 return;
-            }
 
             RenderOverlays(viewport, OverlaySpace.WorldSpaceBelowEntities, worldAABB, worldBounds);
             var worldOverlays = GetOverlaysForSpace(OverlaySpace.WorldSpaceEntities);

Robust.Client/Graphics/Clyde/Clyde.Layout.cs

@@ -23,9 +23,12 @@ namespace Robust.Client.Graphics.Clyde
             // Texture Coords.
             GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, sizeof(Vertex2D), 2 * sizeof(float));
             GL.EnableVertexAttribArray(1);
-            // Colour Modulation.
-            GL.VertexAttribPointer(2, 4, VertexAttribPointerType.Float, false, sizeof(Vertex2D), 4 * sizeof(float));
+            // Texture Coords (2).
+            GL.VertexAttribPointer(2, 2, VertexAttribPointerType.Float, false, sizeof(Vertex2D), 4 * sizeof(float));
             GL.EnableVertexAttribArray(2);
+            // Colour Modulation.
+            GL.VertexAttribPointer(3, 4, VertexAttribPointerType.Float, false, sizeof(Vertex2D), 6 * sizeof(float));
+            GL.EnableVertexAttribArray(3);
         }
 
         // NOTE: This is:
@@ -37,6 +40,7 @@ namespace Robust.Client.Graphics.Clyde
         {
             public readonly Vector2 Position;
             public readonly Vector2 TextureCoordinates;
+            public readonly Vector2 TextureCoordinates2;
             // Note that this color is in linear space.
             public readonly Color Modulate;
 
@@ -48,6 +52,15 @@ namespace Robust.Client.Graphics.Clyde
                 Modulate = modulate;
             }
 
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            public Vertex2D(Vector2 position, Vector2 textureCoordinates, Vector2 textureCoordinates2, Color modulate)
+            {
+                Position = position;
+                TextureCoordinates = textureCoordinates;
+                TextureCoordinates2 = textureCoordinates2;
+                Modulate = modulate;
+            }
+
             [MethodImpl(MethodImplOptions.AggressiveInlining)]
             public Vertex2D(float x, float y, float u, float v, float r, float g, float b, float a)
                 : this(new Vector2(x, y), new Vector2(u, v), new Color(r, g, b, a))

Robust.Client/Graphics/Clyde/Clyde.RenderHandle.cs

@@ -15,7 +15,7 @@ namespace Robust.Client.Graphics.Clyde
     {
         private RenderHandle _renderHandle = default!;
 
-        private sealed class RenderHandle : IRenderHandle
+        internal sealed class RenderHandle : IRenderHandle
         {
             private readonly Clyde _clyde;
             private readonly IEntityManager _entities;
@@ -88,16 +88,21 @@ namespace Robust.Client.Graphics.Clyde
             {
                 var clydeTexture = ExtractTexture(texture, in subRegion, out var csr);
 
-                var (w, h) = clydeTexture.Size;
-                var sr = new Box2(csr.Left / w, (h - csr.Bottom) / h, csr.Right / w, (h - csr.Top) / h);
+                var sr = WorldTextureBoundsToUV(clydeTexture, csr);
 
                 _clyde.DrawTexture(clydeTexture.TextureId, bl, br, tl, tr, in modulate, in sr);
             }
 
+            internal static Box2 WorldTextureBoundsToUV(ClydeTexture texture, UIBox2 csr)
+            {
+                var (w, h) = texture.Size;
+                return new Box2(csr.Left / w, (h - csr.Bottom) / h, csr.Right / w, (h - csr.Top) / h);
+            }
+
             /// <summary>
             /// Converts a subRegion (px) into texture coords (0-1) of a given texture (cells of the textureAtlas).
             /// </summary>
-            private static ClydeTexture ExtractTexture(Texture texture, in UIBox2? subRegion, out UIBox2 sr)
+            internal static ClydeTexture ExtractTexture(Texture texture, in UIBox2? subRegion, out UIBox2 sr)
             {
                 if (texture is AtlasTexture atlas)
                 {

Robust.Client/Graphics/Clyde/Clyde.Rendering.cs

@@ -578,10 +578,10 @@ namespace Robust.Client.Graphics.Clyde
 
             // TODO: split batch if necessary.
             var vIdx = BatchVertexIndex;
-            BatchVertexData[vIdx + 0] = new Vertex2D(bl, texCoords.BottomLeft, modulate);
-            BatchVertexData[vIdx + 1] = new Vertex2D(br, texCoords.BottomRight, modulate);
-            BatchVertexData[vIdx + 2] = new Vertex2D(tr, texCoords.TopRight, modulate);
-            BatchVertexData[vIdx + 3] = new Vertex2D(tl, texCoords.TopLeft, modulate);
+            BatchVertexData[vIdx + 0] = new Vertex2D(bl, texCoords.BottomLeft, new Vector2(0, 0), modulate);
+            BatchVertexData[vIdx + 1] = new Vertex2D(br, texCoords.BottomRight, new Vector2(1, 0), modulate);
+            BatchVertexData[vIdx + 2] = new Vertex2D(tr, texCoords.TopRight, new Vector2(1, 1), modulate);
+            BatchVertexData[vIdx + 3] = new Vertex2D(tl, texCoords.TopLeft, new Vector2(0, 1), modulate);
             BatchVertexIndex += 4;
             QuadBatchIndexWrite(BatchIndexData, ref BatchIndexIndex, (ushort) vIdx);
 

Robust.Client/Graphics/Clyde/Clyde.Textures.cs

@@ -601,7 +601,7 @@ namespace Robust.Client.Graphics.Clyde
             }
         }
 
-        private sealed class ClydeTexture : OwnedTexture
+        internal sealed class ClydeTexture : OwnedTexture
         {
             private readonly Clyde _clyde;
             public readonly bool IsSrgb;

Robust.Client/Graphics/Clyde/Shaders/base-default.frag

@@ -1,4 +1,5 @@
 varying highp vec2 UV;
+varying highp vec2 UV2;
 varying highp vec2 Pos;
 varying highp vec4 VtxModulate;
 

Robust.Client/Graphics/Clyde/Shaders/base-default.vert

@@ -2,10 +2,12 @@
 /*layout (location = 0)*/ attribute vec2 aPos;
 // Texture coordinates.
 /*layout (location = 1)*/ attribute vec2 tCoord;
+/*layout (location = 2)*/ attribute vec2 tCoord2;
 // Colour modulation.
-/*layout (location = 2)*/ attribute vec4 modulate;
+/*layout (location = 3)*/ attribute vec4 modulate;
 
 varying vec2 UV;
+varying vec2 UV2;
 varying vec2 Pos;
 varying vec4 VtxModulate;
 
@@ -36,5 +38,6 @@ void main()
     gl_Position = vec4(VERTEX, 0.0, 1.0);
     Pos = (VERTEX + 1.0) / 2.0;
     UV = mix(modifyUV.xy, modifyUV.zw, tCoord);
+    UV2 = tCoord2;
     VtxModulate = zFromSrgb(modulate);
 }

Robust.Client/Graphics/Clyde/Shaders/base-raw.frag

@@ -1,4 +1,5 @@
 varying highp vec2 UV;
+varying highp vec2 UV2;
 
 uniform sampler2D lightMap;
 

Robust.Client/Graphics/Clyde/Shaders/base-raw.vert

@@ -2,10 +2,12 @@
 /*layout (location = 0)*/ attribute vec2 aPos;
 // Texture coordinates.
 /*layout (location = 1)*/ attribute vec2 tCoord;
+/*layout (location = 2)*/ attribute vec2 tCoord2;
 // Colour modulation.
-/*layout (location = 2)*/ attribute vec4 modulate;
+/*layout (location = 3)*/ attribute vec4 modulate;
 
 varying vec2 UV;
+varying vec2 UV2;
 
 // Maybe we should merge these CPU side.
 // idk yet.
@@ -40,6 +42,7 @@ void main()
     vec2 VERTEX = aPos;
 
     UV = tCoord;
+    UV2 = tCoord2;
 
     // [SHADER_CODE]
 

Robust.Client/Graphics/Drawing/DrawingHandleBase.cs

@@ -114,43 +114,12 @@ namespace Robust.Client.Graphics
             DrawPrimitives(primitiveTopology, White, indices, drawVertices);
         }
 
-        private static void PadVerticesV2(ReadOnlySpan<Vector2> input, Span<DrawVertexUV2DColor> output, Color color)
+        private void PadVerticesV2(ReadOnlySpan<Vector2> input, Span<DrawVertexUV2DColor> output, Color color)
         {
-            if (input.Length == 0)
-                return;
-
-            if (input.Length != output.Length)
+            Color colorLinear = Color.FromSrgb(color);
+            for (var i = 0; i < output.Length; i++)
             {
-                throw new InvalidOperationException("Invalid lengths!");
-            }
-
-            var colorLinear = Color.FromSrgb(color);
-            var colorVec = Unsafe.As<Color, Vector128<float>>(ref colorLinear);
-            var uvVec = Vector128.Create(0, 0, 0.5f, 0.5f);
-            var maskVec = Vector128.Create(0xFFFFFFFF, 0xFFFFFFFF, 0, 0).AsSingle();
-
-            var simdVectors = (nuint)(input.Length / 2);
-            ref readonly var srcBase = ref Unsafe.As<Vector2, float>(ref Unsafe.AsRef(in input[0]));
-            ref var dstBase = ref Unsafe.As<DrawVertexUV2DColor, float>(ref output[0]);
-
-            for (nuint i = 0; i < simdVectors; i++)
-            {
-                var positions = Vector128.LoadUnsafe(in srcBase, i * 4);
-
-                var posColorLower = (positions & maskVec) | uvVec;
-                var posColorUpper = (Vector128.Shuffle(positions, Vector128.Create(2, 3, 0, 0)) & maskVec) | uvVec;
-
-                posColorLower.StoreUnsafe(ref dstBase, i * 16);
-                colorVec.StoreUnsafe(ref dstBase, i * 16 + 4);
-                posColorUpper.StoreUnsafe(ref dstBase, i * 16 + 8);
-                colorVec.StoreUnsafe(ref dstBase, i * 16 + 12);
-            }
-
-            var lastPos = (int)simdVectors * 2;
-            if (lastPos != output.Length)
-            {
-                // Odd number of vertices. Handle the last manually.
-                output[lastPos] = new DrawVertexUV2DColor(input[lastPos], new Vector2(0.5f, 0.5f), colorLinear);
+                output[i] = new DrawVertexUV2DColor(input[i], new Vector2(0.5f, 0.5f), colorLinear);
             }
         }
 
@@ -268,6 +237,8 @@ namespace Robust.Client.Graphics
     {
         public Vector2 Position;
         public Vector2 UV;
+        public Vector2 UV2;
+
         /// <summary>
         ///     Modulation colour for this vertex.
         ///     Note that this color is in linear space.

Robust.Client/Graphics/Shaders/ShaderPrototype.cs

@@ -17,7 +17,7 @@ using Vector4 = Robust.Shared.Maths.Vector4;
 namespace Robust.Client.Graphics
 {
     [Prototype("shader")]
-    public sealed class ShaderPrototype : IPrototype, ISerializationHooks
+    public sealed partial class ShaderPrototype : IPrototype, ISerializationHooks
     {
         [ViewVariables]
         [IdDataField]

Robust.Client/Replays/Loading/ReplayLoadManager.Checkpoints.cs

@@ -88,7 +88,6 @@ public sealed partial class ReplayLoadManager
         if (initMessages != null)
             UpdateMessages(initMessages, uploadedFiles, prototypes, cvars, detachQueue, ref timeBase, true);
         UpdateMessages(messages[0], uploadedFiles, prototypes, cvars, detachQueue, ref timeBase, true);
-        ProcessQueue(GameTick.MaxValue, detachQueue, detached);
 
         var entSpan = state0.EntityStates.Value;
         Dictionary<NetEntity, EntityState> entStates = new(entSpan.Count);
@@ -98,6 +97,8 @@ public sealed partial class ReplayLoadManager
             entStates.Add(entState.NetEntity, modifiedState);
         }
 
+        ProcessQueue(GameTick.MaxValue, detachQueue, detached, entStates);
+
         await callback(0, states.Count, LoadingState.ProcessingFiles, true);
         var playerSpan = state0.PlayerStates.Value;
         Dictionary<NetUserId, SessionState> playerStates = new(playerSpan.Count);
@@ -144,7 +145,7 @@ public sealed partial class ReplayLoadManager
             UpdatePlayerStates(curState.PlayerStates.Span, playerStates);
             UpdateEntityStates(curState.EntityStates.Span, entStates, ref spawnedTracker, ref stateTracker, detached);
             UpdateMessages(messages[i], uploadedFiles, prototypes, cvars, detachQueue, ref timeBase);
-            ProcessQueue(curState.ToSequence, detachQueue, detached);
+            ProcessQueue(curState.ToSequence, detachQueue, detached, entStates);
             UpdateDeletions(curState.EntityDeletions, entStates, detached);
             serverTime[i] = GetTime(curState.ToSequence) - initialTime;
             ticksSinceLastCheckpoint++;
@@ -176,14 +177,28 @@ public sealed partial class ReplayLoadManager
     private void ProcessQueue(
         GameTick curTick,
         Dictionary<GameTick, List<NetEntity>> detachQueue,
-        HashSet<NetEntity> detached)
+        HashSet<NetEntity> detached,
+        Dictionary<NetEntity, EntityState> entStates)
     {
         foreach (var (tick, ents) in detachQueue)
         {
             if (tick > curTick)
                 continue;
             detachQueue.Remove(tick);
-            detached.UnionWith(ents);
+
+            foreach (var e in ents)
+            {
+                if (entStates.ContainsKey(e))
+                    detached.Add(e);
+                else
+                {
+                    // AFAIK this should only happen if the client skipped over some ticks, probably due to packet loss
+                    // I.e., entity was created on tick n, then leaves PVS range on the tick n+1
+                    // If the n-th tick gets dropped, the client only ever receives the pvs-leave message.
+                    // In that case we should just ignore it.
+                    _sawmill.Debug($"Received a PVS detach msg for entity {e} before it was received?");
+                }
+            }
         }
     }
 

Robust.Client/Replays/Playback/ReplayPlaybackManager.Checkpoint.cs

@@ -79,13 +79,14 @@ internal sealed partial class ReplayPlaybackManager
         if (checkpoint.DetachedStates == null)
             return;
 
-        DebugTools.Assert(checkpoint.Detached.Count == checkpoint.DetachedStates.Length); ;
-        var metas = _entMan.GetEntityQuery<MetaDataComponent>();
+        DebugTools.Assert(checkpoint.Detached.Count == checkpoint.DetachedStates.Length);
         foreach (var es in checkpoint.DetachedStates)
         {
-            var uid = _entMan.GetEntity(es.NetEntity);
-            if (metas.TryGetComponent(uid, out var meta) && !meta.EntityDeleted)
+            if (_entMan.TryGetEntityData(es.NetEntity, out var uid, out var meta))
+            {
+                DebugTools.Assert(!meta.EntityDeleted);
                 continue;
+            }
 
             var metaState = (MetaDataComponentState?)es.ComponentChanges.Value?
                 .FirstOrDefault(c => c.NetID == _metaId).State;
@@ -93,18 +94,16 @@ internal sealed partial class ReplayPlaybackManager
             if (metaState == null)
                 throw new MissingMetadataException(es.NetEntity);
 
-            _entMan.CreateEntityUninitialized(metaState.PrototypeId, uid);
-            meta = metas.GetComponent(uid);
+            uid = _entMan.CreateEntity(metaState.PrototypeId, out meta);
 
             // Client creates a client-side net entity for the newly created entity.
             // We need to clear this mapping before assigning the real net id.
             // TODO NetEntity Jank: prevent the client from creating this in the first place.
             _entMan.ClearNetEntity(meta.NetEntity);
+            _entMan.SetNetEntity(uid.Value, es.NetEntity, meta);
 
-            _entMan.SetNetEntity(uid, es.NetEntity, meta);
-
-            _entMan.InitializeEntity(uid, meta);
-            _entMan.StartEntity(uid);
+            _entMan.InitializeEntity(uid.Value, meta);
+            _entMan.StartEntity(uid.Value);
             meta.LastStateApplied = checkpoint.Tick;
         }
     }

Robust.Client/ResourceManagement/ResourceCache.Preload.cs

@@ -10,6 +10,7 @@ using Robust.Shared;
 using Robust.Shared.Audio;
 using Robust.Shared.Configuration;
 using Robust.Shared.ContentPack;
+using Robust.Shared.Graphics;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
 using Robust.Shared.Maths;
@@ -142,6 +143,26 @@ namespace Robust.Client.ResourceManagement
                 }
             });
 
+            // Do not meta-atlas RSIs with custom load parameters.
+            var atlasList = rsiList.Where(x => x.LoadParameters == TextureLoadParameters.Default).ToArray();
+            var nonAtlasList = rsiList.Where(x => x.LoadParameters != TextureLoadParameters.Default).ToArray();
+
+            foreach (var data in nonAtlasList)
+            {
+                if (data.Bad)
+                    continue;
+
+                try
+                {
+                    RSIResource.LoadTexture(Clyde, data);
+                }
+                catch (Exception e)
+                {
+                    sawmill.Error($"Exception while loading RSI {data.Path}:\n{e}");
+                    data.Bad = true;
+                }
+            }
+
             // This combines individual RSI atlases into larger atlases to reduce draw batches. currently this is a VERY
             // lazy bundling and is not at all compact, its basically an atlas of RSI atlases. Really what this should
             // try to do is to have each RSI write directly to the atlas, rather than having each RSI write to its own
@@ -155,7 +176,7 @@ namespace Robust.Client.ResourceManagement
             // TODO allow RSIs to opt out (useful for very big & rare RSIs)
             // TODO combine with (non-rsi) texture atlas?
 
-            Array.Sort(rsiList, (b, a) => (b.AtlasSheet?.Height ?? 0).CompareTo(a.AtlasSheet?.Height ?? 0));
+            Array.Sort(atlasList, (b, a) => (b.AtlasSheet?.Height ?? 0).CompareTo(a.AtlasSheet?.Height ?? 0));
 
             // Each RSI sub atlas has a different size.
             // Even if we iterate through them once to estimate total area, I have NFI how to sanely estimate an optimal square-texture size.
@@ -167,9 +188,9 @@ namespace Robust.Client.ResourceManagement
             Vector2i offset = default;
             int finalized = -1;
             int atlasCount = 0;
-            for (int i = 0; i < rsiList.Length; i++)
+            for (int i = 0; i < atlasList.Length; i++)
             {
-                var rsi = rsiList[i];
+                var rsi = atlasList[i];
                 if (rsi.Bad)
                     continue;
 
@@ -200,14 +221,14 @@ namespace Robust.Client.ResourceManagement
             var height = offset.Y + deltaY;
             var croppedSheet = new Image<Rgba32>(maxSize, height);
             sheet.Blit(new UIBox2i(0, 0, maxSize, height), croppedSheet, default);
-            FinalizeMetaAtlas(rsiList.Length - 1, croppedSheet);
+            FinalizeMetaAtlas(atlasList.Length - 1, croppedSheet);
 
             void FinalizeMetaAtlas(int toIndex, Image<Rgba32> sheet)
             {
                 var atlas = Clyde.LoadTextureFromImage(sheet);
                 for (int i = finalized + 1; i <= toIndex; i++)
                 {
-                    var rsi = rsiList[i];
+                    var rsi = atlasList[i];
                     rsi.AtlasTexture = atlas;
                 }
 
@@ -255,9 +276,10 @@ namespace Robust.Client.ResourceManagement
             }
 
             sawmill.Debug(
-                "Preloaded {CountLoaded} RSIs into {CountAtlas} Atlas(es?) ({CountErrored} errored) in {LoadTime}",
+                "Preloaded {CountLoaded} RSIs into {CountAtlas} Atlas(es?) ({CountNotAtlas} not atlassed, {CountErrored} errored) in {LoadTime}",
                 rsiList.Length,
                 atlasCount,
+                nonAtlasList.Length,
                 errors,
                 sw.Elapsed);
 

Robust.Client/ResourceManagement/ResourceTypes/RSIResource.cs

@@ -40,17 +40,21 @@ namespace Robust.Client.ResourceManagement
             var loadStepData = new LoadStepData {Path = path};
             var manager = dependencies.Resolve<IResourceManager>();
             LoadPreTexture(manager, loadStepData);
-
-            loadStepData.AtlasTexture = dependencies.Resolve<IClyde>().LoadTextureFromImage(
-                loadStepData.AtlasSheet,
-                loadStepData.Path.ToString());
-
+            LoadTexture(dependencies.Resolve<IClyde>(), loadStepData);
             LoadPostTexture(loadStepData);
             LoadFinish(dependencies.Resolve<IResourceCacheInternal>(), loadStepData);
 
             loadStepData.AtlasSheet.Dispose();
         }
 
+        internal static void LoadTexture(IClyde clyde, LoadStepData loadStepData)
+        {
+            loadStepData.AtlasTexture = clyde.LoadTextureFromImage(
+                loadStepData.AtlasSheet,
+                loadStepData.Path.ToString(),
+                loadStepData.LoadParameters);
+        }
+
         internal static void LoadPreTexture(IResourceManager manager, LoadStepData data)
         {
             var manifestPath = data.Path / "meta.json";
@@ -178,6 +182,7 @@ namespace Robust.Client.ResourceManagement
             data.FrameSize = frameSize;
             data.DimX = dimensionX;
             data.CallbackOffsets = callbackOffsets;
+            data.LoadParameters = metadata.LoadParameters;
         }
 
         internal static void LoadPostTexture(LoadStepData data)
@@ -380,6 +385,7 @@ namespace Robust.Client.ResourceManagement
             public Texture AtlasTexture = default!;
             public Vector2i AtlasOffset;
             public RSI Rsi = default!;
+            public TextureLoadParameters LoadParameters;
         }
 
         internal struct StateReg

Robust.Client/UserInterface/Control.Layout.Styling.cs

@@ -0,0 +1,132 @@
+using System;
+using System.Runtime.CompilerServices;
+
+namespace Robust.Client.UserInterface;
+
+public partial class Control
+{
+    private LayoutStyleProperties _layoutStyleOverride;
+    private LayoutStyleProperties _layoutStyleSheet;
+
+    private void UpdateLayoutStyleProperties()
+    {
+        var propertiesSet = LayoutStyleProperties.None;
+
+        // Assumed most controls will have little or no style properties,
+        // so iterating once is less expensive overall then checking 10+ properties.
+        // C# switch statements are compiled efficiently anyways.
+        foreach (var (key, value) in _styleProperties)
+        {
+            switch (key)
+            {
+                case nameof(SizeFlagsStretchRatio):
+                    UpdateField(ref _sizeFlagsStretchRatio, value, LayoutStyleProperties.StretchRatio);
+                    break;
+                case nameof(MinWidth):
+                    UpdateField(ref _minWidth, value, LayoutStyleProperties.MinWidth);
+                    break;
+                case nameof(MinHeight):
+                    UpdateField(ref _minHeight, value, LayoutStyleProperties.MinHeight);
+                    break;
+                case nameof(SetWidth):
+                    UpdateField(ref _setWidth, value, LayoutStyleProperties.SetWidth);
+                    break;
+                case nameof(SetHeight):
+                    UpdateField(ref _setHeight, value, LayoutStyleProperties.SetHeight);
+                    break;
+                case nameof(MaxWidth):
+                    UpdateField(ref _maxWidth, value, LayoutStyleProperties.MaxWidth);
+                    break;
+                case nameof(MaxHeight):
+                    UpdateField(ref _maxHeight, value, LayoutStyleProperties.MaxHeight);
+                    break;
+                case nameof(HorizontalExpand):
+                    UpdateField(ref _horizontalExpand, value, LayoutStyleProperties.HorizontalExpand);
+                    break;
+                case nameof(VerticalExpand):
+                    UpdateField(ref _verticalExpand, value, LayoutStyleProperties.VerticalExpand);
+                    break;
+                case nameof(HorizontalAlignment):
+                    UpdateField(ref _horizontalAlignment, value, LayoutStyleProperties.HorizontalAlignment);
+                    break;
+                case nameof(VerticalAlignment):
+                    UpdateField(ref _verticalAlignment, value, LayoutStyleProperties.VerticalAlignment);
+                    break;
+                case nameof(Margin):
+                    UpdateField(ref _margin, value, LayoutStyleProperties.Margin);
+                    break;
+            }
+        }
+
+        // Reset cleared properties back to defaults.
+        var toClear = _layoutStyleSheet & ~propertiesSet;
+        if (toClear != 0)
+        {
+            ClearField(ref _sizeFlagsStretchRatio, DefaultStretchRatio, LayoutStyleProperties.StretchRatio);
+            ClearField(ref _minWidth, 0, LayoutStyleProperties.MinWidth);
+            ClearField(ref _minHeight, 0, LayoutStyleProperties.MinHeight);
+            ClearField(ref _setWidth, DefaultSetSize, LayoutStyleProperties.SetWidth);
+            ClearField(ref _setHeight, DefaultSetSize, LayoutStyleProperties.SetHeight);
+            ClearField(ref _maxWidth, DefaultMaxSize, LayoutStyleProperties.MaxWidth);
+            ClearField(ref _maxHeight, DefaultMaxSize, LayoutStyleProperties.MaxHeight);
+            ClearField(ref _horizontalExpand, false, LayoutStyleProperties.HorizontalExpand);
+            ClearField(ref _verticalExpand, false, LayoutStyleProperties.VerticalExpand);
+            ClearField(ref _horizontalAlignment, DefaultHAlignment, LayoutStyleProperties.HorizontalAlignment);
+            ClearField(ref _verticalAlignment, DefaultVAlignment, LayoutStyleProperties.VerticalAlignment);
+            ClearField(ref _margin, default, LayoutStyleProperties.Margin);
+        }
+
+        _layoutStyleSheet = propertiesSet;
+
+        return;
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        void UpdateField<T>(ref T field, object value, LayoutStyleProperties flag)
+        {
+            if ((_layoutStyleOverride & flag) != 0)
+                return;
+
+            // TODO: Probably need better error handling...
+            if (value is not T valueCast)
+                return;
+
+            field = valueCast;
+            propertiesSet |= flag;
+        }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        void ClearField<T>(ref T field, T defaultValue, LayoutStyleProperties flag)
+        {
+            if ((toClear & flag) == 0)
+                return;
+
+            field = defaultValue;
+        }
+    }
+
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    private void SetLayoutStyleProp(LayoutStyleProperties flag)
+    {
+        _layoutStyleOverride |= flag;
+    }
+
+    [Flags]
+    private enum LayoutStyleProperties : short
+    {
+        // @formatter:off
+        None                = 0,
+        Margin              = 1 << 0,
+        MinWidth            = 1 << 1,
+        MinHeight           = 1 << 2,
+        SetWidth            = 1 << 3,
+        SetHeight           = 1 << 4,
+        MaxWidth            = 1 << 5,
+        MaxHeight           = 1 << 6,
+        StretchRatio        = 1 << 7,
+        HorizontalExpand    = 1 << 8,
+        VerticalExpand      = 1 << 9,
+        HorizontalAlignment = 1 << 10,
+        VerticalAlignment   = 1 << 11,
+        // @formatter:on
+    }
+}

Robust.Client/UserInterface/Control.Layout.cs

@@ -12,24 +12,30 @@ namespace Robust.Client.UserInterface
 
     public partial class Control
     {
+        private const float DefaultStretchRatio = 1;
+        private const float DefaultSetSize = float.NaN;
+        private const float DefaultMaxSize = float.PositiveInfinity;
+        private const HAlignment DefaultHAlignment = HAlignment.Stretch;
+        private const VAlignment DefaultVAlignment = VAlignment.Stretch;
+
         private Vector2 _size;
 
         [ViewVariables] internal Vector2? PreviousMeasure;
         [ViewVariables] internal UIBox2? PreviousArrange;
 
-        private float _sizeFlagsStretchRatio = 1;
+        private float _sizeFlagsStretchRatio = DefaultStretchRatio;
 
         private float _minWidth;
         private float _minHeight;
-        private float _setWidth = float.NaN;
-        private float _setHeight = float.NaN;
-        private float _maxWidth = float.PositiveInfinity;
-        private float _maxHeight = float.PositiveInfinity;
+        private float _setWidth = DefaultSetSize;
+        private float _setHeight = DefaultSetSize;
+        private float _maxWidth = DefaultMaxSize;
+        private float _maxHeight = DefaultMaxSize;
 
         private bool _horizontalExpand;
         private bool _verticalExpand;
-        private HAlignment _horizontalAlignment = HAlignment.Stretch;
-        private VAlignment _verticalAlignment = VAlignment.Stretch;
+        private HAlignment _horizontalAlignment = DefaultHAlignment;
+        private VAlignment _verticalAlignment = DefaultVAlignment;
         private Thickness _margin;
         private bool _measuring;
         private bool _arranging;
@@ -53,6 +59,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _margin = value;
+                SetLayoutStyleProp(LayoutStyleProperties.Margin);
                 InvalidateMeasure();
             }
         }
@@ -242,6 +249,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _horizontalAlignment = value;
+                SetLayoutStyleProp(LayoutStyleProperties.HorizontalAlignment);
                 InvalidateArrange();
             }
         }
@@ -258,6 +266,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _verticalAlignment = value;
+                SetLayoutStyleProp(LayoutStyleProperties.VerticalAlignment);
                 InvalidateArrange();
             }
         }
@@ -276,6 +285,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _horizontalExpand = value;
+                SetLayoutStyleProp(LayoutStyleProperties.HorizontalExpand);
                 Parent?.InvalidateMeasure();
             }
         }
@@ -294,6 +304,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _verticalExpand = value;
+                SetLayoutStyleProp(LayoutStyleProperties.VerticalExpand);
                 Parent?.InvalidateArrange();
             }
         }
@@ -318,6 +329,7 @@ namespace Robust.Client.UserInterface
 
                 _sizeFlagsStretchRatio = value;
 
+                SetLayoutStyleProp(LayoutStyleProperties.StretchRatio);
                 Parent?.InvalidateArrange();
             }
         }
@@ -394,6 +406,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _minWidth = value;
+                SetLayoutStyleProp(LayoutStyleProperties.MinWidth);
                 InvalidateMeasure();
             }
         }
@@ -408,6 +421,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _minHeight = value;
+                SetLayoutStyleProp(LayoutStyleProperties.MinHeight);
                 InvalidateMeasure();
             }
         }
@@ -422,6 +436,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _setWidth = value;
+                SetLayoutStyleProp(LayoutStyleProperties.SetWidth);
                 InvalidateMeasure();
             }
         }
@@ -436,6 +451,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _setHeight = value;
+                SetLayoutStyleProp(LayoutStyleProperties.SetHeight);
                 InvalidateMeasure();
             }
         }
@@ -450,6 +466,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _maxWidth = value;
+                SetLayoutStyleProp(LayoutStyleProperties.MaxWidth);
                 InvalidateMeasure();
             }
         }
@@ -464,6 +481,7 @@ namespace Robust.Client.UserInterface
             set
             {
                 _maxHeight = value;
+                SetLayoutStyleProp(LayoutStyleProperties.MaxHeight);
                 InvalidateMeasure();
             }
         }

Robust.Client/UserInterface/Control.Styling.cs

@@ -239,6 +239,7 @@ namespace Robust.Client.UserInterface
 
         protected virtual void StylePropertiesChanged()
         {
+            UpdateLayoutStyleProperties();
             InvalidateMeasure();
         }
 

Robust.Client/UserInterface/Control.cs

@@ -641,7 +641,11 @@ namespace Robust.Client.UserInterface
 
             foreach (var child in Children.ToArray())
             {
-                RemoveChild(child);
+                // This checks fails in some obscure cases like using the element inspector in the dev window.
+                // Why? Well I could probably spend 15 minutes in a debugger to find out,
+                // but I'd probably still end up with this fix.
+                if (child.Parent == this)
+                    RemoveChild(child);
             }
         }
 

Robust.Client/UserInterface/Controllers/UIController.cs

@@ -5,7 +5,6 @@ using Robust.Shared.Timing;
 
 namespace Robust.Client.UserInterface.Controllers;
 
-// Notices your UIController, *UwU Whats this?*
 /// <summary>
 ///     Each <see cref="UIController"/> is instantiated as a singleton by <see cref="UserInterfaceManager"/>
 ///     <see cref="UIController"/> can use <see cref="DependencyAttribute"/> for regular IoC dependencies

Robust.Client/UserInterface/Controls/RichTextLabel.cs

@@ -6,6 +6,7 @@ using Robust.Client.UserInterface.RichText;
 using Robust.Shared.IoC;
 using Robust.Shared.Maths;
 using Robust.Shared.Utility;
+using Robust.Shared.ViewVariables;
 
 namespace Robust.Client.UserInterface.Controls
 {
@@ -16,6 +17,26 @@ namespace Robust.Client.UserInterface.Controls
 
         private FormattedMessage? _message;
         private RichTextEntry _entry;
+        private float _lineHeightScale = 1;
+        private bool _lineHeightOverride;
+
+        [ViewVariables(VVAccess.ReadWrite)]
+        public float LineHeightScale
+        {
+            get
+            {
+                if (!_lineHeightOverride && TryGetStyleProperty(nameof(LineHeightScale), out float value))
+                    return value;
+
+                return _lineHeightScale;
+            }
+            set
+            {
+                _lineHeightScale = value;
+                _lineHeightOverride = true;
+                InvalidateMeasure();
+            }
+        }
 
         public RichTextLabel()
         {
@@ -47,7 +68,7 @@ namespace Robust.Client.UserInterface.Controls
             }
 
             var font = _getFont();
-            _entry.Update(font, availableSize.X * UIScale, UIScale);
+            _entry.Update(font, availableSize.X * UIScale, UIScale, LineHeightScale);
 
             return new Vector2(_entry.Width / UIScale, _entry.Height / UIScale);
         }
@@ -61,7 +82,7 @@ namespace Robust.Client.UserInterface.Controls
                 return;
             }
 
-            _entry.Draw(handle, _getFont(), SizeBox, 0, new MarkupDrawingContext(), UIScale);
+            _entry.Draw(handle, _getFont(), SizeBox, 0, new MarkupDrawingContext(), UIScale, LineHeightScale);
         }
 
         [Pure]

Robust.Client/UserInterface/Controls/Slider.cs

@@ -2,6 +2,7 @@
 using System.Numerics;
 using Robust.Client.Graphics;
 using Robust.Shared.Input;
+using Robust.Shared.Log;
 using Robust.Shared.Maths;
 using static Robust.Client.UserInterface.Controls.LayoutContainer;
 
@@ -32,6 +33,11 @@ namespace Robust.Client.UserInterface.Controls
 
         public bool Grabbed => _grabbed;
 
+        /// <summary>
+        /// Whether the slider can be adjusted.
+        /// </summary>
+        public bool Disabled { get; set; }
+
         public StyleBox? ForegroundStyleBoxOverride
         {
             get => _foregroundStyleBoxOverride;
@@ -132,7 +138,7 @@ namespace Robust.Client.UserInterface.Controls
         {
             base.KeyBindDown(args);
 
-            if (args.Function != EngineKeyFunctions.UIClick)
+            if (args.Function != EngineKeyFunctions.UIClick || Disabled)
             {
                 return;
             }
@@ -146,7 +152,7 @@ namespace Robust.Client.UserInterface.Controls
         {
             base.KeyBindUp(args);
 
-            if (args.Function != EngineKeyFunctions.UIClick) return;
+            if (args.Function != EngineKeyFunctions.UIClick || !_grabbed) return;
 
             _grabbed = false;
             OnReleased?.Invoke(this);

Robust.Client/UserInterface/Controls/VerticalTabContainer.xaml

@@ -0,0 +1,34 @@
+<!-- Organised with tabs in a vertical list to the left and the contents to the right -->
+<BoxContainer Name="Container" xmlns="https://spacestation14.io"
+              xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+              xmlns:graphics="clr-namespace:Robust.Client.Graphics"
+              Orientation="Horizontal"
+              MouseFilter="Pass">
+    <ScrollContainer VerticalExpand="True"
+                     HScrollEnabled="False"
+                     ReturnMeasure="True"
+                     Margin="5 5 0 5">
+        <PanelContainer Margin="5" VerticalExpand="False"
+                        VerticalAlignment="Top">
+            <PanelContainer.PanelOverride>
+                <graphics:StyleBoxFlat BackgroundColor="#1B1B1E" />
+            </PanelContainer.PanelOverride>
+            <BoxContainer Name="TabContainer" Margin="5" Orientation="Vertical"/>
+        </PanelContainer>
+        </ScrollContainer>
+    <ScrollContainer VerticalExpand="True"
+                     HScrollEnabled="False"
+                     HorizontalAlignment="Stretch"
+                     HorizontalExpand="True"
+                     ReturnMeasure="True"
+                     Margin="0 5 5 5">
+        <PanelContainer Margin="5" HorizontalExpand="True" HorizontalAlignment="Stretch">
+            <PanelContainer.PanelOverride>
+                <graphics:StyleBoxFlat BackgroundColor="#1B1B1E" />
+            </PanelContainer.PanelOverride>
+            <BoxContainer Margin="5"
+                          Orientation="Vertical"
+                          Name="ContentsContainer"/>
+        </PanelContainer>
+    </ScrollContainer>
+</BoxContainer>

Robust.Client/UserInterface/Controls/VerticalTabContainer.xaml.cs

@@ -0,0 +1,97 @@
+using System.Collections.Generic;
+using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface.XAML;
+using Robust.Shared.Maths;
+
+namespace Robust.Client.UserInterface.Controls;
+
+[GenerateTypedNameReferences]
+public sealed partial class VerticalTabContainer : BoxContainer
+{
+    private readonly Dictionary<Control, BaseButton> _tabs = new();
+
+    // Just used to order controls in case one gets removed.
+    private readonly List<Control> _controls = new();
+
+    private readonly ButtonGroup _tabGroup = new(false);
+
+    private Control? _currentControl;
+
+    public VerticalTabContainer()
+    {
+        RobustXamlLoader.Load(this);
+    }
+
+    public int AddTab(Control control, string title)
+    {
+        var button = new Button()
+        {
+            Text = title,
+            Group = _tabGroup,
+        };
+
+        TabContainer.AddChild(button);
+        ContentsContainer.AddChild(control);
+        var index = ChildCount - 1;
+        button.OnPressed += args =>
+        {
+            SelectTab(control);
+        };
+
+        _controls.Add(control);
+        _tabs.Add(control, button);
+
+        // Existing tabs
+        if (ContentsContainer.ChildCount > 1)
+        {
+            control.Visible = false;
+        }
+        // First tab
+        else
+        {
+            SelectTab(control);
+        }
+
+        return index;
+    }
+
+    protected override void ChildRemoved(Control child)
+    {
+        if (_tabs.Remove(child, out var button))
+        {
+            button.Dispose();
+        }
+
+        // Set the current tab to a different control
+        if (_currentControl == child)
+        {
+            var previous = _controls.IndexOf(child) - 1;
+
+            if (previous > -1)
+            {
+                var setControl = _controls[previous];
+                SelectTab(setControl);
+            }
+            else
+            {
+                _currentControl = null;
+            }
+        }
+
+        _controls.Remove(child);
+        base.ChildRemoved(child);
+    }
+
+    private void SelectTab(Control control)
+    {
+        if (_currentControl != null)
+        {
+            _currentControl.Visible = false;
+        }
+
+        var button = _tabs[control];
+        button.Pressed = true;
+        control.Visible = true;
+        _currentControl = control;
+    }
+}

Robust.Client/UserInterface/CustomControls/DebugMonitorControls/DebugCoordsPanel.cs

@@ -20,6 +20,7 @@ namespace Robust.Client.UserInterface.CustomControls.DebugMonitorControls
         [Dependency] private readonly IEntityManager _entityManager = default!;
         [Dependency] private readonly IClyde _displayManager = default!;
         [Dependency] private readonly IMapManager _mapManager = default!;
+        [Dependency] private readonly IBaseClient _baseClient = default!;
 
         private readonly StringBuilder _textBuilder = new();
         private readonly char[] _textBuffer = new char[1024];
@@ -58,30 +59,36 @@ namespace Robust.Client.UserInterface.CustomControls.DebugMonitorControls
 
             _textBuilder.Clear();
 
+            var isInGame = _baseClient.RunLevel.IsInGameLike();
             var mouseScreenPos = _inputManager.MouseScreenPosition;
             var screenSize = _displayManager.ScreenSize;
             var screenScale = _displayManager.MainWindow.ContentScale;
 
-            EntityCoordinates mouseGridPos;
-            TileRef tile;
+            EntityCoordinates mouseGridPos = default;
+            TileRef tile = default;
+            MapCoordinates mouseWorldMap = default;
 
-            var mouseWorldMap = _eyeManager.PixelToMap(mouseScreenPos);
-            if (mouseWorldMap == MapCoordinates.Nullspace)
-                return;
-
-            var mapSystem = _entityManager.System<SharedMapSystem>();
-            var xformSystem = _entityManager.System<SharedTransformSystem>();
-
-            if (_mapManager.TryFindGridAt(mouseWorldMap, out var mouseGridUid, out var mouseGrid))
+            if (isInGame)
             {
-                mouseGridPos = mapSystem.MapToGrid(mouseGridUid, mouseWorldMap);
-                tile = mapSystem.GetTileRef(mouseGridUid, mouseGrid, mouseGridPos);
-            }
-            else
-            {
-                mouseGridPos = new EntityCoordinates(_mapManager.GetMapEntityId(mouseWorldMap.MapId),
-                    mouseWorldMap.Position);
-                tile = new TileRef(EntityUid.Invalid, mouseGridPos.ToVector2i(_entityManager, _mapManager, xformSystem), Tile.Empty);
+                mouseWorldMap = _eyeManager.PixelToMap(mouseScreenPos);
+                if (mouseWorldMap != MapCoordinates.Nullspace)
+                {
+                    var mapSystem = _entityManager.System<SharedMapSystem>();
+                    var xformSystem = _entityManager.System<SharedTransformSystem>();
+
+                    if (_mapManager.TryFindGridAt(mouseWorldMap, out var mouseGridUid, out var mouseGrid))
+                    {
+                        mouseGridPos = mapSystem.MapToGrid(mouseGridUid, mouseWorldMap);
+                        tile = mapSystem.GetTileRef(mouseGridUid, mouseGrid, mouseGridPos);
+                    }
+                    else
+                    {
+                        mouseGridPos = new EntityCoordinates(_mapManager.GetMapEntityId(mouseWorldMap.MapId),
+                            mouseWorldMap.Position);
+                        tile = new TileRef(EntityUid.Invalid,
+                            mouseGridPos.ToVector2i(_entityManager, _mapManager, xformSystem), Tile.Empty);
+                    }
+                }
             }
 
             var controlHovered = UserInterfaceManager.CurrentlyHovered;
@@ -95,32 +102,37 @@ Mouse Pos:
     {tile}
     GUI: {controlHovered}");
 
-            _textBuilder.AppendLine("\nAttached NetEntity:");
-            var controlledEntity = _playerManager.LocalSession?.AttachedEntity ?? EntityUid.Invalid;
-
-            if (controlledEntity == EntityUid.Invalid)
+            if (isInGame)
             {
-                _textBuilder.AppendLine("No attached netentity.");
-            }
-            else
-            {
-                var entityTransform = _entityManager.GetComponent<TransformComponent>(controlledEntity);
-                var playerWorldOffset = xformSystem.GetMapCoordinates(entityTransform);
-                var playerScreen = _eyeManager.WorldToScreen(playerWorldOffset.Position);
+                var xformSystem = _entityManager.System<SharedTransformSystem>();
 
-                var playerCoordinates = entityTransform.Coordinates;
-                var playerRotation = xformSystem.GetWorldRotation(entityTransform);
-                var gridRotation = entityTransform.GridUid != null
-                    ? xformSystem.GetWorldRotation(entityTransform.GridUid.Value)
-                    : Angle.Zero;
+                _textBuilder.AppendLine("\nAttached NetEntity:");
+                var controlledEntity = _playerManager.LocalSession?.AttachedEntity ?? EntityUid.Invalid;
 
-                _textBuilder.Append($@"    Screen: {playerScreen}
+                if (controlledEntity == EntityUid.Invalid)
+                {
+                    _textBuilder.AppendLine("No attached netentity.");
+                }
+                else
+                {
+                    var entityTransform = _entityManager.GetComponent<TransformComponent>(controlledEntity);
+                    var playerWorldOffset = xformSystem.GetMapCoordinates(entityTransform);
+                    var playerScreen = _eyeManager.WorldToScreen(playerWorldOffset.Position);
+
+                    var playerCoordinates = entityTransform.Coordinates;
+                    var playerRotation = xformSystem.GetWorldRotation(entityTransform);
+                    var gridRotation = entityTransform.GridUid != null
+                        ? xformSystem.GetWorldRotation(entityTransform.GridUid.Value)
+                        : Angle.Zero;
+
+                    _textBuilder.Append($@"    Screen: {playerScreen}
     {playerWorldOffset}
     {_entityManager.GetNetCoordinates(playerCoordinates)}
     Rotation: {playerRotation.Degrees:F2}°
     NEntId: {_entityManager.GetNetEntity(controlledEntity)}
     Grid NEntId: {_entityManager.GetNetEntity(entityTransform.GridUid)}
     Grid Rotation: {gridRotation.Degrees:F2}°");
+                }
             }
 
             _contents.TextMemory = FormatHelpers.BuilderToMemory(_textBuilder, _textBuffer);

Robust.Client/UserInterface/RichText/FontPrototype.cs

@@ -5,7 +5,7 @@ using Robust.Shared.Utility;
 namespace Robust.Client.UserInterface.RichText;
 
 [Prototype("font")]
-public sealed class FontPrototype : IPrototype
+public sealed partial class FontPrototype : IPrototype
 {
     [IdDataField]
     public string ID { get; private set; } = default!;

Robust.Client/UserInterface/RichTextEntry.cs

@@ -71,7 +71,8 @@ namespace Robust.Client.UserInterface
         /// <param name="defaultFont">The font being used for display.</param>
         /// <param name="maxSizeX">The maximum horizontal size of the container of this entry.</param>
         /// <param name="uiScale"></param>
-        public void Update(Font defaultFont, float maxSizeX, float uiScale)
+        /// <param name="lineHeightScale"></param>
+        public void Update(Font defaultFont, float maxSizeX, float uiScale, float lineHeightScale = 1)
         {
             // This method is gonna suck due to complexity.
             // Bear with me here.
@@ -159,7 +160,7 @@ namespace Robust.Client.UserInterface
                     if (!context.Font.TryPeek(out var font))
                         font = defaultFont;
 
-                    src.Height += font.GetLineHeight(uiScale);
+                    src.Height += GetLineHeight(font, uiScale, lineHeightScale);
                 }
             }
         }
@@ -170,7 +171,8 @@ namespace Robust.Client.UserInterface
             UIBox2 drawBox,
             float verticalOffset,
             MarkupDrawingContext context,
-            float uiScale)
+            float uiScale,
+            float lineHeightScale = 1)
         {
             context.Clear();
             context.Color.Push(_defaultColor);
@@ -197,7 +199,7 @@ namespace Robust.Client.UserInterface
                     if (lineBreakIndex < LineBreaks.Count &&
                         LineBreaks[lineBreakIndex] == globalBreakCounter)
                     {
-                        baseLine = new Vector2(drawBox.Left, baseLine.Y + font.GetLineHeight(uiScale) + controlYAdvance);
+                        baseLine = new Vector2(drawBox.Left, baseLine.Y + GetLineHeight(font, uiScale, lineHeightScale) + controlYAdvance);
                         controlYAdvance = 0;
                         lineBreakIndex += 1;
                     }
@@ -216,7 +218,7 @@ namespace Robust.Client.UserInterface
                 control.Position = new Vector2(baseLine.X * invertedScale, (baseLine.Y - defaultFont.GetAscent(uiScale)) * invertedScale);
                 control.Measure(new Vector2(Width, Height));
                 var advanceX = control.DesiredPixelSize.X;
-                controlYAdvance = Math.Max(0f, (control.DesiredPixelSize.Y - font.GetLineHeight(uiScale)) * invertedScale);
+                controlYAdvance = Math.Max(0f, (control.DesiredPixelSize.Y - GetLineHeight(font, uiScale, lineHeightScale)) * invertedScale);
                 baseLine += new Vector2(advanceX, 0);
             }
         }
@@ -242,5 +244,11 @@ namespace Robust.Client.UserInterface
             tag.PopDrawContext(node, context);
             return tag.TextAfter(node);
         }
+
+        private static int GetLineHeight(Font font, float uiScale, float lineHeightScale)
+        {
+            var height = font.GetLineHeight(uiScale);
+            return (int)(height * lineHeightScale);
+        }
     }
 }

Robust.Client/UserInterface/Themes/UiTheme.cs

@@ -1,12 +1,10 @@
 using System;
 using System.Collections.Frozen;
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using Robust.Client.Graphics;
 using Robust.Client.ResourceManagement;
 using Robust.Shared.ContentPack;
-using Robust.Shared.Graphics;
 using Robust.Shared.IoC;
 using Robust.Shared.Log;
 using Robust.Shared.Maths;
@@ -18,7 +16,7 @@ using Robust.Shared.ViewVariables;
 namespace Robust.Client.UserInterface.Themes;
 
 [Prototype("uiTheme")]
-public sealed class UITheme : IPrototype
+public sealed partial class UITheme : IPrototype
 {
     private IResourceCache? _cache;
     private IUserInterfaceManager? _uiMan;

Robust.Client/UserInterface/UserInterfaceManager.Themes.cs

@@ -2,6 +2,7 @@
 using Robust.Client.UserInterface.Themes;
 using Robust.Shared;
 using Robust.Shared.Log;
+using Robust.Shared.Prototypes;
 
 namespace Robust.Client.UserInterface;
 
@@ -18,11 +19,29 @@ internal partial class UserInterfaceManager
     {
         DefaultTheme = _protoManager.Index<UITheme>(UITheme.DefaultName);
         CurrentTheme = DefaultTheme;
+        ReloadThemes();
+        _configurationManager.OnValueChanged(CVars.InterfaceTheme, SetThemeOrPrevious, true);
+        _protoManager.PrototypesReloaded += OnPrototypesReloaded;
+    }
+
+    private void OnPrototypesReloaded(PrototypesReloadedEventArgs eventArgs)
+    {
+        if (eventArgs.WasModified<UITheme>())
+        {
+            _sawmillUI.Debug("Reloading UI themes due to prototype reload");
+            ReloadThemes();
+        }
+    }
+
+    private void ReloadThemes()
+    {
+        _themes.Clear();
         foreach (var proto in _protoManager.EnumeratePrototypes<UITheme>())
         {
             _themes.Add(proto.ID, proto);
         }
-        _configurationManager.OnValueChanged(CVars.InterfaceTheme, SetThemeOrPrevious, true);
+
+        SetThemeOrPrevious(CurrentTheme.ID);
     }
 
     //Try to set the current theme, if the theme is not found do nothing

Robust.Roslyn.Shared/Diagnostics.cs

@@ -28,6 +28,7 @@ public static class Diagnostics
     public const string IdComponentPauseNoFields = "RA0022";
     public const string IdComponentPauseNoParentAttribute = "RA0023";
     public const string IdComponentPauseWrongTypeAttribute = "RA0024";
+    public const string IdDependencyFieldAssigned = "RA0025";
 
     public static SuppressionDescriptor MeansImplicitAssignment =>
         new SuppressionDescriptor("RADC1000", "CS0649", "Marked as implicitly assigned.");

Robust.Server/Console/Commands/TestbedCommand.cs

@@ -70,6 +70,11 @@ namespace Robust.Server.Console.Commands
             }
 
             var mapId = new MapId(mapInt);
+            if (!_map.MapExists(mapId))
+            {
+                shell.WriteError($"map {args[0]} does not exist");
+                return;
+            }
 
             if (shell.Player == null)
             {
@@ -110,13 +115,6 @@ namespace Robust.Server.Console.Commands
 
         private void SetupPlayer(MapId mapId, IConsoleShell shell)
         {
-            if (mapId == MapId.Nullspace) return;
-
-            if (!_map.MapExists(mapId))
-            {
-                _map.CreateMap(mapId);
-            }
-
             _map.SetMapPaused(mapId, false);
             var mapUid = _map.GetMapEntityIdOrThrow(mapId);
             _ent.System<Gravity2DController>().SetGravity(mapUid, new Vector2(0, -9.8f));

Robust.Server/GameObjects/EntitySystems/MapLoaderSystem.cs

@@ -49,7 +49,6 @@ public sealed class MapLoaderSystem : EntitySystem
     private ISawmill _logLoader = default!;
     private ISawmill _logWriter = default!;
 
-    private static readonly MapLoadOptions DefaultLoadOptions = new();
     private const int MapFormatVersion = 6;
     private const int BackwardsVersion = 2;
 
@@ -132,7 +131,7 @@ public sealed class MapLoaderSystem : EntitySystem
     public bool TryLoad(MapId mapId, string path, [NotNullWhen(true)] out IReadOnlyList<EntityUid>? rootUids,
         MapLoadOptions? options = null)
     {
-        options ??= DefaultLoadOptions;
+        options ??= new();
 
         var resPath = new ResPath(path).ToRootedPath();
 
@@ -658,11 +657,13 @@ public sealed class MapLoaderSystem : EntitySystem
         var xformQuery = GetEntityQuery<TransformComponent>();
         // We just need to cache the old mapuid and point to the new mapuid.
 
-        if (HasComp<MapComponent>(rootNode))
+        if (TryComp(rootNode, out MapComponent? mapComp))
         {
             // If map exists swap out
-            if (_mapManager.MapExists(data.TargetMap))
+            if (_mapSystem.TryGetMap(data.TargetMap, out var existing))
             {
+                data.Options.DoMapInit |= _mapSystem.IsInitialized(data.TargetMap);
+                data.MapIsPaused = _mapSystem.IsPaused(existing.Value);
                 // Map exists but we also have a map file with stuff on it soooo swap out the old map.
                 if (data.Options.LoadMap)
                 {
@@ -675,26 +676,28 @@ public sealed class MapLoaderSystem : EntitySystem
                         data.Options.Rotation = Angle.Zero;
                     }
 
-                    _mapManager.SetMapEntity(data.TargetMap, rootNode);
+                    Del(existing);
                     EnsureComp<LoadedMapComponent>(rootNode);
+
+                    mapComp.MapId = data.TargetMap;
+                    DebugTools.Assert(mapComp.LifeStage < ComponentLifeStage.Initializing);
                 }
                 // Otherwise just ignore the map in the file.
                 else
                 {
                     var oldRootUid = data.Entities[0];
-                    var newRootUid = _mapManager.GetMapEntityId(data.TargetMap);
-                    data.Entities[0] = newRootUid;
+                    data.Entities[0] = existing.Value;
 
                     foreach (var ent in data.Entities)
                     {
-                        if (ent == newRootUid)
+                        if (ent == existing)
                             continue;
 
                         var xform = xformQuery.GetComponent(ent);
 
                         if (!xform.ParentUid.IsValid() || xform.ParentUid.Equals(oldRootUid))
                         {
-                            _transform.SetParent(ent, xform, newRootUid);
+                            _transform.SetParent(ent, xform, existing.Value);
                         }
                     }
 
@@ -703,16 +706,9 @@ public sealed class MapLoaderSystem : EntitySystem
             }
             else
             {
-                // If we're loading a file with a map then swap out the entityuid
-                // TODO: Mapmanager nonsense
-                var AAAAA = _mapManager.CreateMap(data.TargetMap);
-
-                if (!data.MapIsPostInit)
-                {
-                    _mapManager.AddUninitializedMap(data.TargetMap);
-                }
-
-                _mapManager.SetMapEntity(data.TargetMap, rootNode);
+                data.MapIsPaused = !data.MapIsPostInit;
+                mapComp.MapId = data.TargetMap;
+                DebugTools.Assert(mapComp.LifeStage < ComponentLifeStage.Initializing);
                 EnsureComp<LoadedMapComponent>(rootNode);
 
                 // Nothing should have invalid uid except for the root node.
@@ -721,17 +717,15 @@ public sealed class MapLoaderSystem : EntitySystem
         else
         {
             // No map file root, in that case create a new map / get the one we're loading onto.
-            var mapNode = _mapManager.GetMapEntityId(data.TargetMap);
-
-            if (!mapNode.IsValid())
+            if (!_mapSystem.TryGetMap(data.TargetMap, out var mapNode))
             {
                 // Map doesn't exist so we'll start it up now so we can re-attach the preinit entities to it for later.
-                _mapManager.CreateMap(data.TargetMap);
-                _mapManager.AddUninitializedMap(data.TargetMap);
-                mapNode = _mapManager.GetMapEntityId(data.TargetMap);
-                DebugTools.Assert(mapNode.IsValid());
+                mapNode = _mapSystem.CreateMap(data.TargetMap, false);
             }
 
+            data.Options.DoMapInit |= _mapSystem.IsInitialized(data.TargetMap);
+            data.MapIsPaused = _mapSystem.IsPaused(mapNode.Value);
+
             // If anything has an invalid parent (e.g. it's some form of root node) then parent it to the map.
             foreach (var ent in data.Entities)
             {
@@ -743,12 +737,11 @@ public sealed class MapLoaderSystem : EntitySystem
 
                 if (!xform.ParentUid.IsValid())
                 {
-                    _transform.SetParent(ent, xform, mapNode);
+                    _transform.SetParent(ent, xform, mapNode.Value);
                 }
             }
         }
 
-        data.MapIsPaused = _mapManager.IsMapPaused(data.TargetMap);
         _logLoader.Debug($"Swapped out root node in {_stopwatch.Elapsed}");
     }
 
@@ -896,7 +889,7 @@ public sealed class MapLoaderSystem : EntitySystem
         {
             EntityManager.SetLifeStage(metadata, EntityLifeStage.MapInitialized);
         }
-        else if (_mapManager.IsMapInitialized(data.TargetMap))
+        else if (data.Options.DoMapInit)
         {
             _serverEntityManager.RunMapInit(uid, metadata);
         }
@@ -964,7 +957,7 @@ public sealed class MapLoaderSystem : EntitySystem
         // Yes, post-init maps do not have EntityLifeStage >= EntityLifeStage.MapInitialized
         bool postInit;
         if (TryComp(uid, out MapComponent? mapComp))
-            postInit = !mapComp.MapPreInit;
+            postInit = mapComp.MapInitialized;
         else
             postInit = metadata.EntityLifeStage >= EntityLifeStage.MapInitialized;
 
@@ -1098,17 +1091,17 @@ public sealed class MapLoaderSystem : EntitySystem
         }
     }
 
-    private bool IsSaveable(EntityUid uid, EntityQuery<MetaDataComponent> metaQuery, EntityQuery<TransformComponent> transformQuery)
+    private bool IsSaveable(EntityUid uid)
     {
         // Don't serialize things parented to un savable things.
         // For example clothes inside a person.
         while (uid.IsValid())
         {
-            var meta = metaQuery.GetComponent(uid);
+            var meta = MetaData(uid);
 
             if (meta.EntityDeleted || meta.EntityPrototype?.MapSavable == false) break;
 
-            uid = transformQuery.GetComponent(uid).ParentUid;
+            uid = Transform(uid).ParentUid;
         }
 
         // If we manage to get up to the map (root node) then it's saveable.
@@ -1123,7 +1116,7 @@ public sealed class MapLoaderSystem : EntitySystem
         EntityQuery<TransformComponent> transformQuery,
         EntityQuery<MapSaveIdComponent> saveCompQuery)
     {
-        if (!IsSaveable(uid, metaQuery, transformQuery))
+        if (!IsSaveable(uid))
             return;
 
         entities.Add(uid);

Robust.Server/GameObjects/EntitySystems/MapSystem.cs

@@ -5,9 +5,9 @@ using Robust.Shared.Collections;
 using Robust.Shared.Configuration;
 using Robust.Shared.GameObjects;
 using Robust.Shared.IoC;
+using Robust.Shared.Map;
 using Robust.Shared.Map.Components;
 using Robust.Shared.Map.Events;
-using Robust.Shared.Physics.Dynamics;
 
 namespace Robust.Server.GameObjects
 {
@@ -18,6 +18,16 @@ namespace Robust.Server.GameObjects
 
         private bool _deleteEmptyGrids;
 
+        protected override MapId GetNextMapId()
+        {
+            var id = new MapId(++LastMapId);
+            while (MapManager.MapExists(id))
+            {
+                id = new MapId(++LastMapId);
+            }
+            return id;
+        }
+
         protected override void UpdatePvsChunks(Entity<TransformComponent, MetaDataComponent> grid)
         {
             _pvs.GridParentChanged(grid);
@@ -31,11 +41,6 @@ namespace Robust.Server.GameObjects
             Subs.CVar(_cfg, CVars.GameDeleteEmptyGrids, SetGridDeletion, true);
         }
 
-        protected override void OnMapAdd(EntityUid uid, MapComponent component, ComponentAdd args)
-        {
-            EnsureComp<PhysicsMapComponent>(uid);
-        }
-
         private void SetGridDeletion(bool value)
         {
             _deleteEmptyGrids = value;

Robust.Server/GameObjects/EntitySystems/UserInterfaceSystem.cs

@@ -1,416 +1,9 @@
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using JetBrains.Annotations;
-using Robust.Server.Player;
-using Robust.Shared.Enums;
+using System.Collections;
 using Robust.Shared.GameObjects;
-using Robust.Shared.IoC;
-using Robust.Shared.Player;
-using Robust.Shared.Utility;
 
-namespace Robust.Server.GameObjects
+namespace Robust.Server.GameObjects;
+
+public sealed class UserInterfaceSystem : SharedUserInterfaceSystem
 {
-    public sealed class UserInterfaceSystem : SharedUserInterfaceSystem
-    {
-        [Dependency] private readonly IPlayerManager _playerMan = default!;
-        [Dependency] private readonly TransformSystem _xformSys = default!;
-
-        private EntityQuery<IgnoreUIRangeComponent> _ignoreUIRangeQuery;
-
-        private readonly List<ICommonSession> _sessionCache = new();
-
-        /// <inheritdoc />
-        public override void Initialize()
-        {
-            base.Initialize();
-
-            SubscribeNetworkEvent<BoundUIWrapMessage>(OnMessageReceived);
-            _playerMan.PlayerStatusChanged += OnPlayerStatusChanged;
-
-            _ignoreUIRangeQuery = GetEntityQuery<IgnoreUIRangeComponent>();
-        }
-
-        public override void Shutdown()
-        {
-            base.Shutdown();
-
-            _playerMan.PlayerStatusChanged -= OnPlayerStatusChanged;
-        }
-
-        private void OnPlayerStatusChanged(object? sender, SessionStatusEventArgs args)
-        {
-            if (args.NewStatus != SessionStatus.Disconnected)
-                return;
-
-            if (!OpenInterfaces.TryGetValue(args.Session, out var buis))
-                return;
-
-            foreach (var bui in buis.ToArray())
-            {
-                CloseShared(bui, args.Session);
-            }
-        }
-
-        /// <inheritdoc />
-        public override void Update(float frameTime)
-        {
-            var xformQuery = GetEntityQuery<TransformComponent>();
-            var query = AllEntityQuery<ActiveUserInterfaceComponent, TransformComponent>();
-
-            while (query.MoveNext(out var uid, out var activeUis, out var xform))
-            {
-                foreach (var ui in activeUis.Interfaces)
-                {
-                    CheckRange(uid, activeUis, ui, xform, xformQuery);
-
-                    if (!ui.StateDirty)
-                        continue;
-
-                    ui.StateDirty = false;
-
-                    foreach (var (player, state) in ui.PlayerStateOverrides)
-                    {
-                        RaiseNetworkEvent(state, player.Channel);
-                    }
-
-                    if (ui.LastStateMsg == null)
-                        continue;
-
-                    foreach (var session in ui.SubscribedSessions)
-                    {
-                        if (!ui.PlayerStateOverrides.ContainsKey(session))
-                            RaiseNetworkEvent(ui.LastStateMsg, session.Channel);
-                    }
-                }
-            }
-        }
-
-        /// <summary>
-        ///     Verify that the subscribed clients are still in range of the interface.
-        /// </summary>
-        private void CheckRange(EntityUid uid, ActiveUserInterfaceComponent activeUis, PlayerBoundUserInterface ui, TransformComponent transform, EntityQuery<TransformComponent> query)
-        {
-            if (ui.InteractionRange <= 0)
-                return;
-
-            // We have to cache the set of sessions because Unsubscribe modifies the original.
-            _sessionCache.Clear();
-            _sessionCache.AddRange(ui.SubscribedSessions);
-
-            var uiPos = _xformSys.GetWorldPosition(transform, query);
-            var uiMap = transform.MapID;
-
-            foreach (var session in _sessionCache)
-            {
-                // The component manages the set of sessions, so this invalid session should be removed soon.
-                if (!query.TryGetComponent(session.AttachedEntity, out var xform))
-                    continue;
-
-                if (_ignoreUIRangeQuery.HasComponent(session.AttachedEntity))
-                    continue;
-
-                // Handle pluggable BoundUserInterfaceCheckRangeEvent
-                var checkRangeEvent = new BoundUserInterfaceCheckRangeEvent(uid, ui, session);
-                RaiseLocalEvent(uid, ref checkRangeEvent, broadcast: true);
-                if (checkRangeEvent.Result == BoundUserInterfaceRangeResult.Pass)
-                    continue;
-
-                if (checkRangeEvent.Result == BoundUserInterfaceRangeResult.Fail)
-                {
-                    CloseUi(ui, session, activeUis);
-                    continue;
-                }
-
-                DebugTools.Assert(checkRangeEvent.Result == BoundUserInterfaceRangeResult.Default);
-
-                if (uiMap != xform.MapID)
-                {
-                    CloseUi(ui, session, activeUis);
-                    continue;
-                }
-
-                var distanceSquared = (uiPos - _xformSys.GetWorldPosition(xform, query)).LengthSquared();
-                if (distanceSquared > ui.InteractionRangeSqrd)
-                    CloseUi(ui, session, activeUis);
-            }
-        }
-
-        #region Get BUI
-
-        public bool HasUi(EntityUid uid, Enum uiKey, UserInterfaceComponent? ui = null)
-        {
-            if (!Resolve(uid, ref ui))
-                return false;
-
-            return ui.Interfaces.ContainsKey(uiKey);
-        }
-
-        public PlayerBoundUserInterface GetUi(EntityUid uid, Enum uiKey, UserInterfaceComponent? ui = null)
-        {
-            if (!Resolve(uid, ref ui))
-                throw new InvalidOperationException($"Cannot get {typeof(PlayerBoundUserInterface)} from an entity without {typeof(UserInterfaceComponent)}!");
-
-            return ui.Interfaces[uiKey];
-        }
-
-        public PlayerBoundUserInterface? GetUiOrNull(EntityUid uid, Enum uiKey, UserInterfaceComponent? ui = null)
-        {
-            return TryGetUi(uid, uiKey, out var bui, ui)
-                ? bui
-                : null;
-        }
-
-        /// <summary>
-        ///     Return UIs a session has open.
-        ///     Null if empty.
-        /// </summary>
-        public List<PlayerBoundUserInterface>? GetAllUIsForSession(ICommonSession session)
-        {
-            OpenInterfaces.TryGetValue(session, out var value);
-            return value;
-        }
-        #endregion
-
-        public bool IsUiOpen(EntityUid uid, Enum uiKey, UserInterfaceComponent? ui = null)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            return bui.SubscribedSessions.Count > 0;
-        }
-
-        public bool SessionHasOpenUi(EntityUid uid, Enum uiKey, ICommonSession session, UserInterfaceComponent? ui = null)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            return bui.SubscribedSessions.Contains(session);
-        }
-
-        /// <summary>
-        ///     Sets a state. This can be used for stateful UI updating.
-        ///     This state is sent to all clients, and automatically sent to all new clients when they open the UI.
-        ///     Pretty much how NanoUI did it back in ye olde BYOND.
-        /// </summary>
-        /// <param name="state">
-        ///     The state object that will be sent to all current and future client.
-        ///     This can be null.
-        /// </param>
-        /// <param name="session">
-        ///     The player session to send this new state to.
-        ///     Set to null for sending it to every subscribed player session.
-        /// </param>
-        public bool TrySetUiState(EntityUid uid,
-            Enum uiKey,
-            BoundUserInterfaceState state,
-            ICommonSession? session = null,
-            UserInterfaceComponent? ui = null,
-            bool clearOverrides = true)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            SetUiState(bui, state, session, clearOverrides);
-            return true;
-        }
-
-        /// <summary>
-        ///     Sets a state. This can be used for stateful UI updating.
-        ///     This state is sent to all clients, and automatically sent to all new clients when they open the UI.
-        ///     Pretty much how NanoUI did it back in ye olde BYOND.
-        /// </summary>
-        /// <param name="state">
-        ///     The state object that will be sent to all current and future client.
-        ///     This can be null.
-        /// </param>
-        /// <param name="session">
-        ///     The player session to send this new state to.
-        ///     Set to null for sending it to every subscribed player session.
-        /// </param>
-        public void SetUiState(PlayerBoundUserInterface bui, BoundUserInterfaceState state, ICommonSession? session = null, bool clearOverrides = true)
-        {
-            var msg = new BoundUIWrapMessage(GetNetEntity(bui.Owner), new UpdateBoundStateMessage(state), bui.UiKey);
-            if (session == null)
-            {
-                bui.LastStateMsg = msg;
-                if (clearOverrides)
-                    bui.PlayerStateOverrides.Clear();
-            }
-            else
-            {
-                bui.PlayerStateOverrides[session] = msg;
-            }
-
-            bui.StateDirty = true;
-        }
-
-        #region Close
-        protected override void CloseShared(PlayerBoundUserInterface bui, ICommonSession session, ActiveUserInterfaceComponent? activeUis = null)
-        {
-            var owner = bui.Owner;
-            bui._subscribedSessions.Remove(session);
-            bui.PlayerStateOverrides.Remove(session);
-
-            if (OpenInterfaces.TryGetValue(session, out var buis))
-                buis.Remove(bui);
-
-            RaiseLocalEvent(owner, new BoundUIClosedEvent(bui.UiKey, owner, session));
-
-            if (bui._subscribedSessions.Count == 0)
-                DeactivateInterface(bui.Owner, bui, activeUis);
-        }
-
-        /// <summary>
-        ///     Closes this all interface for any clients that have any open.
-        /// </summary>
-        public bool TryCloseAll(EntityUid uid, Shared.GameObjects.ActiveUserInterfaceComponent? aui = null)
-        {
-            if (!Resolve(uid, ref aui, false))
-                return false;
-
-            foreach (var ui in aui.Interfaces)
-            {
-                CloseAll(ui);
-            }
-
-            return true;
-        }
-
-        /// <summary>
-        ///     Closes this specific interface for any clients that have it open.
-        /// </summary>
-        public bool TryCloseAll(EntityUid uid, Enum uiKey, UserInterfaceComponent? ui = null)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            CloseAll(bui);
-            return true;
-        }
-
-        /// <summary>
-        ///     Closes this interface for any clients that have it open.
-        /// </summary>
-        public void CloseAll(PlayerBoundUserInterface bui)
-        {
-            foreach (var session in bui.SubscribedSessions.ToArray())
-            {
-                CloseUi(bui, session);
-            }
-        }
-
-        #endregion
-
-        #region SendMessage
-
-        /// <summary>
-        ///     Send a BUI message to all connected player sessions.
-        /// </summary>
-        public bool TrySendUiMessage(EntityUid uid, Enum uiKey, BoundUserInterfaceMessage message, UserInterfaceComponent? ui = null)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            SendUiMessage(bui, message);
-            return true;
-        }
-
-        /// <summary>
-        ///     Send a BUI message to all connected player sessions.
-        /// </summary>
-        public void SendUiMessage(PlayerBoundUserInterface bui, BoundUserInterfaceMessage message)
-        {
-            var msg = new BoundUIWrapMessage(GetNetEntity(bui.Owner), message, bui.UiKey);
-            foreach (var session in bui.SubscribedSessions)
-            {
-                RaiseNetworkEvent(msg, session.Channel);
-            }
-        }
-
-        /// <summary>
-        ///     Send a BUI message to a specific player session.
-        /// </summary>
-        public bool TrySendUiMessage(EntityUid uid, Enum uiKey, BoundUserInterfaceMessage message, ICommonSession session, UserInterfaceComponent? ui = null)
-        {
-            if (!TryGetUi(uid, uiKey, out var bui, ui))
-                return false;
-
-            return TrySendUiMessage(bui, message, session);
-        }
-
-        /// <summary>
-        ///     Send a BUI message to a specific player session.
-        /// </summary>
-        public bool TrySendUiMessage(PlayerBoundUserInterface bui, BoundUserInterfaceMessage message, ICommonSession session)
-        {
-            if (!bui.SubscribedSessions.Contains(session))
-                return false;
-
-            RaiseNetworkEvent(new BoundUIWrapMessage(GetNetEntity(bui.Owner), message, bui.UiKey), session.Channel);
-            return true;
-        }
-
-        #endregion
-    }
-
-    /// <summary>
-    /// Raised by <see cref="UserInterfaceSystem"/> to check whether an interface is still accessible by its user.
-    /// </summary>
-    [ByRefEvent]
-    [PublicAPI]
-    public struct BoundUserInterfaceCheckRangeEvent
-    {
-        /// <summary>
-        /// The entity owning the UI being checked for.
-        /// </summary>
-        public readonly EntityUid Target;
-
-        /// <summary>
-        /// The UI itself.
-        /// </summary>
-        /// <returns></returns>
-        public readonly PlayerBoundUserInterface UserInterface;
-
-        /// <summary>
-        /// The player for which the UI is being checked.
-        /// </summary>
-        public readonly ICommonSession Player;
-
-        /// <summary>
-        /// The result of the range check.
-        /// </summary>
-        public BoundUserInterfaceRangeResult Result;
-
-        public BoundUserInterfaceCheckRangeEvent(
-            EntityUid target,
-            PlayerBoundUserInterface userInterface,
-            ICommonSession player)
-        {
-            Target = target;
-            UserInterface = userInterface;
-            Player = player;
-        }
-    }
-
-    /// <summary>
-    /// Possible results for a <see cref="BoundUserInterfaceCheckRangeEvent"/>.
-    /// </summary>
-    public enum BoundUserInterfaceRangeResult : byte
-    {
-        /// <summary>
-        /// Run built-in range check.
-        /// </summary>
-        Default,
-
-        /// <summary>
-        /// Range check passed, UI is accessible.
-        /// </summary>
-        Pass,
-
-        /// <summary>
-        /// Range check failed, UI is inaccessible.
-        /// </summary>
-        Fail
-    }
 }

Robust.Server/GameObjects/ServerEntityManager.cs

@@ -86,7 +86,7 @@ namespace Robust.Server.GameObjects
             StartEntity(entity);
         }
 
-        private protected override EntityUid CreateEntity(string? prototypeName, out MetaDataComponent metadata, IEntityLoadContext? context = null)
+        internal override EntityUid CreateEntity(string? prototypeName, out MetaDataComponent metadata, IEntityLoadContext? context = null)
         {
             if (prototypeName == null)
                 return base.CreateEntity(prototypeName, out metadata, context);

Robust.Server/Maps/MapLoadOptions.cs

@@ -53,5 +53,7 @@ namespace Robust.Server.Maps
         /// This should be set to false if you want to load a map file onto an existing map and do not wish to overwrite the existing entity.
         /// </remarks>
         public bool LoadMap { get; set; } = true;
+
+        public bool DoMapInit = false;
     }
 }

Robust.Server/ServerStatus/StatusHost.cs

@@ -256,7 +256,7 @@ namespace Robust.Server.ServerStatus
                 _context = context;
                 RequestMethod = new HttpMethod(context.Request.HttpMethod!);
 
-                var headers = new Dictionary<string, StringValues>();
+                var headers = new Dictionary<string, StringValues>(StringComparer.OrdinalIgnoreCase);
                 foreach (string? key in context.Request.Headers.Keys)
                 {
                     if (key == null)

Robust.Server/ServerStatus/WatchdogApi.cs

@@ -157,11 +157,14 @@ namespace Robust.Server.ServerStatus
             try
             {
                 // Passing null as content works so...
-                await _httpClient.PostAsync(new Uri(_baseUri, $"server_api/{_watchdogKey}/ping"), null!);
+                _sawmill.Debug("Sending ping to watchdog...");
+                using var resp = await _httpClient.PostAsync(new Uri(_baseUri, $"server_api/{_watchdogKey}/ping"), null!);
+                resp.EnsureSuccessStatusCode();
+                _sawmill.Debug("Succeeded in sending ping to watchdog");
             }
             catch (HttpRequestException e)
             {
-                _sawmill.Warning("Failed to send ping to watchdog:\n{0}", e);
+                _sawmill.Error("Failed to send ping to watchdog:\n{0}", e);
             }
         }
 

Robust.Shared.Maths/Color.cs

@@ -592,7 +592,11 @@ namespace Robust.Shared.Maths
             if (c != 0)
             {
                 if (max == rgb.R)
+                {
                     h = (rgb.G - rgb.B) / c % 6.0f;
+                    if (h < 0f)
+                        h += 6.0f;
+                }
                 else if (max == rgb.G)
                     h = (rgb.B - rgb.R) / c + 2.0f;
                 else if (max == rgb.B)
@@ -774,7 +778,11 @@ namespace Robust.Shared.Maths
 
             var h = 0.0f;
             if (max == rgb.R)
+            {
                 h = (rgb.G - rgb.B) / c % 6.0f;
+                if (h < 0f)
+                    h += 6.0f;
+            }
             else if (max == rgb.G)
                 h = (rgb.B - rgb.R) / c + 2.0f;
             else if (max == rgb.B)

Robust.Shared/Analyzers/AccessAttribute.cs

@@ -1,6 +1,6 @@
 using System;
 
-#if NETSTANDARD2_0
+#if ROBUST_ANALYZERS_IMPL
 namespace Robust.Shared.Analyzers.Implementation;
 #else
 namespace Robust.Shared.Analyzers;

Robust.Shared/Analyzers/AccessPermissions.cs

@@ -1,6 +1,6 @@
 using System;
 
-#if NETSTANDARD2_0
+#if ROBUST_ANALYZERS_IMPL
 namespace Robust.Shared.Analyzers.Implementation;
 #else
 namespace Robust.Shared.Analyzers;

Robust.Shared/Analyzers/NotNullableFlagAttribute.cs

@@ -1,6 +1,6 @@
 using System;
 
-#if NETSTANDARD2_0
+#if ROBUST_ANALYZERS_IMPL
 namespace Robust.Shared.Analyzers.Implementation;
 #else
 namespace Robust.Shared.Analyzers;

Robust.Shared/Analyzers/PreferGenericVariantAttribute.cs

@@ -1,6 +1,6 @@
 using System;
 
-#if NETSTANDARD2_0
+#if ROBUST_ANALYZERS_IMPL
 namespace Robust.Shared.Analyzers.Implementation;
 #else
 namespace Robust.Shared.Analyzers;

Robust.Shared/Audio/AudioMetadataPrototype.cs

@@ -10,7 +10,7 @@ namespace Robust.Shared.Audio;
 /// to allow the server to know audio lengths without shipping the large audio files themselves.
 /// </summary>
 [Prototype(ProtoName)]
-public sealed class AudioMetadataPrototype : IPrototype
+public sealed partial class AudioMetadataPrototype : IPrototype
 {
     public const string ProtoName = "audioMetadata";
 

Robust.Shared/Audio/AudioPresetPrototype.cs

@@ -9,7 +9,7 @@ namespace Robust.Shared.Audio;
 /// This can be used by <see cref="Content.Shared.Audio.SharedContentAudioSystem"/> to apply an audio preset.
 /// </summary>
 [Prototype("audioPreset")]
-public sealed class AudioPresetPrototype : IPrototype
+public sealed partial class AudioPresetPrototype : IPrototype
 {
     [IdDataField]
     public string ID { get; } = default!;

Robust.Shared/Audio/Components/AudioComponent.cs

@@ -6,6 +6,7 @@ using Robust.Shared.Audio.Sources;
 using Robust.Shared.Audio.Systems;
 using Robust.Shared.GameObjects;
 using Robust.Shared.GameStates;
+using Robust.Shared.Serialization;
 using Robust.Shared.Serialization.Manager.Attributes;
 using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom;
 using Robust.Shared.ViewVariables;
@@ -90,11 +91,24 @@ public sealed partial class AudioComponent : Component, IAudioSource
     public void StartPlaying() => Source.StartPlaying();
 
     /// <inheritdoc />
-    public void StopPlaying() => Source.StopPlaying();
+    public void StopPlaying()
+    {
+        PlaybackPosition = 0f;
+        Source.StopPlaying();
+    }
 
     /// <inheritdoc />
     public void Restart() => Source.Restart();
 
+    [DataField, AutoNetworkedField]
+    public AudioState State = AudioState.Playing;
+
+    /// <summary>
+    /// Time when the audio was paused so we can offset it later if relevant.
+    /// </summary>
+    [DataField, AutoNetworkedField]
+    public TimeSpan? PauseTime;
+
     /// <summary>
     /// <see cref="IAudioSource.Playing"/>
     /// </summary>
@@ -208,6 +222,7 @@ public sealed partial class AudioComponent : Component, IAudioSource
     /// <see cref="IAudioSource.PlaybackPosition"/>
     /// </summary>
     [ViewVariables]
+    [Access(Other = AccessPermissions.ReadWriteExecute)]
     public float PlaybackPosition
     {
         get => Source.PlaybackPosition;
@@ -240,6 +255,14 @@ public sealed partial class AudioComponent : Component, IAudioSource
     }
 }
 
+[Serializable, NetSerializable]
+public enum AudioState : byte
+{
+    Stopped,
+    Playing,
+    Paused,
+}
+
 [Flags]
 public enum AudioFlags : byte
 {

Robust.Shared/Audio/SoundCollectionPrototype.cs

@@ -1,13 +1,13 @@
+using System.Collections.Generic;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Serialization.Manager.Attributes;
 using Robust.Shared.Utility;
 using Robust.Shared.ViewVariables;
-using System.Collections.Generic;
 
 namespace Robust.Shared.Audio;
 
 [Prototype("soundCollection")]
-public sealed class SoundCollectionPrototype : IPrototype
+public sealed partial class SoundCollectionPrototype : IPrototype
 {
     [ViewVariables]
     [IdDataField]

Robust.Shared/Audio/Systems/SharedAudioSystem.cs

@@ -55,6 +55,141 @@ public abstract partial class SharedAudioSystem : EntitySystem
         SubscribeLocalEvent<AudioComponent, EntityUnpausedEvent>(OnAudioUnpaused);
     }
 
+    /// <summary>
+    /// Sets the playback position of audio to the specified spot.
+    /// </summary>
+    public void SetPlaybackPosition(Entity<AudioComponent?>? nullEntity, float position)
+    {
+        if (nullEntity == null)
+            return;
+
+        var entity = nullEntity.Value;
+
+        if (!Resolve(entity.Owner, ref entity.Comp, false))
+            return;
+
+        var audioLength = GetAudioLength(entity.Comp.FileName);
+
+        if (audioLength.TotalSeconds < position)
+        {
+            // Just stop it and return
+            if (!_netManager.IsClient)
+                QueueDel(nullEntity.Value);
+
+            entity.Comp.StopPlaying();
+            return;
+        }
+
+        if (position < 0f)
+        {
+            Log.Error($"Tried to set playback position for {ToPrettyString(entity.Owner)} / {entity.Comp.FileName} outside of bounds");
+            return;
+        }
+
+        // If we're paused then the current position is <pause time - start time>, else it's <cur time - start time>
+        var currentPos = (entity.Comp.PauseTime ?? Timing.CurTime) - entity.Comp.AudioStart;
+        var timeOffset = TimeSpan.FromSeconds(position - currentPos.TotalSeconds);
+
+        DebugTools.Assert(currentPos > TimeSpan.Zero);
+
+        // Rounding.
+        if (Math.Abs(timeOffset.TotalSeconds) <= 0.01)
+        {
+            return;
+        }
+
+        if (entity.Comp.PauseTime != null)
+        {
+            entity.Comp.PauseTime = entity.Comp.PauseTime.Value + timeOffset;
+
+            // Paused audio doesn't have TimedDespawn so.
+        }
+        else
+        {
+            // Bump it back so the actual playback positions moves forward
+            entity.Comp.AudioStart -= timeOffset;
+
+            // need to ensure it doesn't despawn too early.
+            if (TryComp(entity.Owner, out TimedDespawnComponent? despawn))
+            {
+                despawn.Lifetime -= (float) timeOffset.TotalSeconds;
+            }
+        }
+
+        entity.Comp.PlaybackPosition = position;
+        // Network the new playback position.
+        Dirty(entity);
+    }
+
+    /// <summary>
+    /// Calculates playback position considering length paused.
+    /// </summary>
+    /// <param name="component"></param>
+    /// <returns></returns>
+    private float GetPlaybackPosition(AudioComponent component)
+    {
+        return (float) (Timing.CurTime - (component.PauseTime ?? TimeSpan.Zero) - component.AudioStart).TotalSeconds;
+    }
+
+    /// <summary>
+    /// Sets the shared state for an audio entity.
+    /// </summary>
+    public void SetState(EntityUid? entity, AudioState state, bool force = false, AudioComponent? component = null)
+    {
+        if (entity == null || !Resolve(entity.Value, ref component, false))
+            return;
+
+        if (component.State == state && !force)
+            return;
+
+        // Unpause it
+        if (component.State == AudioState.Paused && state == AudioState.Playing)
+        {
+            var pauseOffset = Timing.CurTime - component.PauseTime;
+            component.AudioStart += pauseOffset ?? TimeSpan.Zero;
+            component.PlaybackPosition = (float) (Timing.CurTime - component.AudioStart).TotalSeconds;
+        }
+
+        // If we were stopped then played then restart audiostart to now.
+        if (component.State == AudioState.Stopped && state == AudioState.Playing)
+        {
+            component.AudioStart = Timing.CurTime;
+            component.PauseTime = null;
+        }
+
+        switch (state)
+        {
+            case AudioState.Stopped:
+                component.AudioStart = Timing.CurTime;
+                component.PauseTime = null;
+                component.StopPlaying();
+                RemComp<TimedDespawnComponent>(entity.Value);
+                break;
+            case AudioState.Paused:
+                // Set it to current time so we can easily unpause it later.
+                component.PauseTime = Timing.CurTime;
+                component.Pause();
+                RemComp<TimedDespawnComponent>(entity.Value);
+                break;
+            case AudioState.Playing:
+                component.PauseTime = null;
+                component.StartPlaying();
+
+                // Reset TimedDespawn so the audio still gets cleaned up.
+
+                if (!component.Looping)
+                {
+                    var timed = EnsureComp<TimedDespawnComponent>(entity.Value);
+                    var audioLength = GetAudioLength(component.FileName);
+                    timed.Lifetime = (float) audioLength.TotalSeconds + 0.01f;
+                }
+                break;
+        }
+
+        component.State = state;
+        Dirty(entity.Value, component);
+    }
+
     protected void SetZOffset(float value)
     {
         ZOffset = value;
@@ -505,4 +640,12 @@ public abstract partial class SharedAudioSystem : EntitySystem
     {
         public NetEntity NetEntity;
     }
+
+    public bool IsPlaying(EntityUid? stream, AudioComponent? component = null)
+    {
+        if (stream == null || !Resolve(stream.Value, ref component, false))
+            return false;
+
+        return component.State == AudioState.Playing;
+    }
 }

Robust.Shared/CVars.cs

@@ -851,7 +851,7 @@ namespace Robust.Shared
         /// See the documentation of the <see cref="Network.AuthMode"/> enum for values.
         /// </summary>
         public static readonly CVarDef<int> AuthMode =
-            CVarDef.Create("auth.mode", (int) Network.AuthMode.Optional, CVar.SERVERONLY);
+            CVarDef.Create("auth.mode", (int) Network.AuthMode.Required, CVar.SERVERONLY);
 
         /// <summary>
         /// Allow unauthenticated localhost connections, even if the auth mode is set to required.
@@ -1445,7 +1445,7 @@ namespace Robust.Shared
         /// Comma-separated list of URLs of hub servers to advertise to.
         /// </summary>
         public static readonly CVarDef<string> HubUrls =
-            CVarDef.Create("hub.hub_urls", "https://central.spacestation14.io/hub/", CVar.SERVERONLY);
+            CVarDef.Create("hub.hub_urls", "https://hub.spacestation14.com/", CVar.SERVERONLY);
 
         /// <summary>
         /// URL of this server to advertise.

Robust.Shared/Configuration/ConfigurationManager.cs

@@ -558,17 +558,21 @@ namespace Robust.Shared.Configuration
             OverrideDefault(def.Name, value);
         }
 
-        /// <inheritdoc />
-        public T GetCVar<T>(string name)
+        public object GetCVar(string name)
         {
             using var _ = Lock.ReadGuard();
             if (_configVars.TryGetValue(name, out var cVar) && cVar.Registered)
-                //TODO: Make flags work, required non-derpy net system.
-                return (T)(GetConfigVarValue(cVar))!;
+                return GetConfigVarValue(cVar);
 
             throw new InvalidConfigurationException($"Trying to get unregistered variable '{name}'");
         }
 
+        /// <inheritdoc />
+        public T GetCVar<T>(string name)
+        {
+            return (T)GetCVar(name);
+        }
+
         public T GetCVar<T>(CVarDef<T> def) where T : notnull
         {
             return GetCVar<T>(def.Name);

Robust.Shared/Configuration/EnvironmentVariables.cs

@@ -1,9 +1,10 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 
 namespace Robust.Shared.Configuration
 {
-    public static class EnvironmentVariables
+    internal static class EnvironmentVariables
     {
         /// <summary>
         /// The environment variable for configuring CVar overrides. The value
@@ -12,23 +13,38 @@ namespace Robust.Shared.Configuration
         /// </summary>
         public const string ConfigVarEnvironmentVariable = "ROBUST_CVARS";
 
+        public const string SingleVarPrefix = "ROBUST_CVAR_";
+
         /// <summary>
         /// Get the CVar overrides defined in the relevant environment variable.
         /// </summary>
-        public static IEnumerable<(string, string)> GetEnvironmentCVars()
+        internal static IEnumerable<(string, string)> GetEnvironmentCVars()
         {
-            var eVarString = Environment.GetEnvironmentVariable(ConfigVarEnvironmentVariable);
-
-            if (eVarString == null)
-            {
-                yield break;
-            }
+            // Handle ROBUST_CVARS.
+            var eVarString = Environment.GetEnvironmentVariable(ConfigVarEnvironmentVariable) ?? "";
 
             foreach (var cVarPair in eVarString.Split(';', StringSplitOptions.RemoveEmptyEntries))
             {
                 var pairParts = cVarPair.Split('=', 2);
                 yield return (pairParts[0], pairParts[1]);
             }
+
+            // Handle ROBUST_CVAR_*
+
+            foreach (DictionaryEntry entry in Environment.GetEnvironmentVariables())
+            {
+                var key = (string)entry.Key;
+                var value = (string?)entry.Value;
+
+                if (value == null)
+                    continue;
+
+                if (!key.StartsWith(SingleVarPrefix))
+                    continue;
+
+                var varName = key[SingleVarPrefix.Length..].Replace("__", ".");
+                yield return (varName, value);
+            }
         }
     }
 }

Robust.Shared/Configuration/IConfigurationManager.cs

@@ -118,6 +118,13 @@ namespace Robust.Shared.Configuration
         /// <param name="value">The new default value of the CVar.</param>
         void OverrideDefault<T>(CVarDef<T> def, T value) where T : notnull;
 
+        /// <summary>
+        /// Get the value of a CVar.
+        /// </summary>
+        /// <param name="name">The name of the CVar.</param>
+        /// <returns></returns>
+        object GetCVar(string name);
+
         /// <summary>
         /// Get the value of a CVar.
         /// </summary>

Robust.Shared/Console/Commands/MapCommands.cs

@@ -10,7 +10,8 @@ namespace Robust.Shared.Console.Commands;
 
 sealed class AddMapCommand : LocalizedCommands
 {
-    [Dependency] private readonly IMapManager _map = default!;
+    [Dependency] private readonly IMapManagerInternal _map = default!;
+    [Dependency] private readonly IEntityManager _entMan = default!;
 
     public override string Command => "addmap";
     public override bool RequireServerOrSingleplayer => true;
@@ -24,11 +25,8 @@ sealed class AddMapCommand : LocalizedCommands
 
         if (!_map.MapExists(mapId))
         {
-            _map.CreateMap(mapId);
-            if (args.Length >= 2 && args[1] == "false")
-            {
-                _map.AddUninitializedMap(mapId);
-            }
+            var init = args.Length < 2 || !bool.Parse(args[1]);
+            _entMan.System<SharedMapSystem>().CreateMap(mapId, runMapInit: init);
 
             shell.WriteLine($"Map with ID {mapId} created.");
             return;

Robust.Shared/Containers/SharedContainerSystem.Insert.cs

@@ -135,6 +135,25 @@ public abstract partial class SharedContainerSystem
         return true;
     }
 
+    /// <summary>
+    /// Attempts to insert an entity into a container. If it fails, it will instead drop the entity next to the
+    /// container entity.
+    /// </summary>
+    /// <returns>Whether or not the entity was successfully inserted</returns>
+    public bool InsertOrDrop(Entity<TransformComponent?, MetaDataComponent?, PhysicsComponent?> toInsert,
+        BaseContainer container,
+        TransformComponent? containerXform = null)
+    {
+        if (!Resolve(toInsert.Owner, ref toInsert.Comp1) || !Resolve(container.Owner, ref containerXform))
+            return false;
+
+        if (Insert(toInsert, container, containerXform))
+            return true;
+
+        _transform.DropNextTo(toInsert, (container.Owner, containerXform));
+        return false;
+    }
+
     /// <summary>
     /// Checks if the entity can be inserted into the given container.
     /// </summary>

Robust.Shared/Containers/SharedContainerSystem.cs

@@ -168,9 +168,16 @@ namespace Robust.Shared.Containers
             return containerManager.Containers.TryGetValue(id, out container);
         }
 
-        public bool TryGetContainingContainer(EntityUid uid, EntityUid containedUid, [NotNullWhen(true)] out BaseContainer? container, ContainerManagerComponent? containerManager = null, bool skipExistCheck = false)
+        [Obsolete("Use variant without skipExistCheck argument")]
+        public bool TryGetContainingContainer(EntityUid uid, EntityUid containedUid, [NotNullWhen(true)] out BaseContainer? container, bool skipExistCheck)
         {
-            if (!Resolve(uid, ref containerManager, false) || !(skipExistCheck || Exists(containedUid)))
+            return TryGetContainingContainer(uid, containedUid, out container);
+        }
+
+        public bool TryGetContainingContainer(EntityUid uid, EntityUid containedUid, [NotNullWhen(true)] out BaseContainer? container, ContainerManagerComponent? containerManager = null)
+        {
+            DebugTools.Assert(Exists(containedUid));
+            if (!Resolve(uid, ref containerManager, false))
             {
                 container = null;
                 return false;
@@ -191,7 +198,8 @@ namespace Robust.Shared.Containers
 
         public bool ContainsEntity(EntityUid uid, EntityUid containedUid, ContainerManagerComponent? containerManager = null)
         {
-            if (!Resolve(uid, ref containerManager, false) || !Exists(containedUid))
+            DebugTools.Assert(Exists(containedUid));
+            if (!Resolve(uid, ref containerManager, false))
                 return false;
 
             foreach (var container in containerManager.Containers.Values)
@@ -251,7 +259,7 @@ namespace Robust.Shared.Containers
             if (!Resolve(uid, ref transform, false))
                 return false;
 
-            return TryGetContainingContainer(transform.ParentUid, uid, out container, skipExistCheck: true);
+            return TryGetContainingContainer(transform.ParentUid, uid, out container);
         }
 
         /// <summary>

Robust.Shared/ContentPack/AssemblyTypeChecker.Parsing.cs

@@ -32,7 +32,7 @@ namespace Robust.Shared.ContentPack
             String("short").ThenReturn(PrimitiveTypeCode.Int16);
 
         private static readonly Parser<char, PrimitiveTypeCode> UInt16TypeParser =
-            String("ushort").ThenReturn(PrimitiveTypeCode.UInt32);
+            String("ushort").ThenReturn(PrimitiveTypeCode.UInt16);
 
         private static readonly Parser<char, PrimitiveTypeCode> Int32TypeParser =
             String("int").ThenReturn(PrimitiveTypeCode.Int32);

Robust.Shared/ContentPack/Sandbox.yml

@@ -84,12 +84,146 @@ Types:
       - "bool get_HasContents()"
   Lidgren.Network:
     NetBuffer:
-      All: True
+      Methods:
+      - "byte[] get_Data()"
+      - "void set_Data(byte[])"
+      - "int get_LengthBytes()"
+      - "void set_LengthBytes(int)"
+      - "int get_LengthBits()"
+      - "void set_LengthBits(int)"
+      - "long get_Position()"
+      - "void set_Position(long)"
+      - "int get_PositionInBytes()"
+      - "byte[] PeekDataBuffer()"
+      - "bool PeekBoolean()"
+      - "byte PeekByte()"
+      - "sbyte PeekSByte()"
+      - "byte PeekByte(int)"
+      - "System.Span`1<byte> PeekBytes(System.Span`1<byte>)"
+      - "byte[] PeekBytes(int)"
+      - "void PeekBytes(byte[], int, int)"
+      - "short PeekInt16()"
+      - "ushort PeekUInt16()"
+      - "int PeekInt32()"
+      - "int PeekInt32(int)"
+      - "uint PeekUInt32()"
+      - "uint PeekUInt32(int)"
+      - "ulong PeekUInt64()"
+      - "long PeekInt64()"
+      - "ulong PeekUInt64(int)"
+      - "long PeekInt64(int)"
+      - "float PeekFloat()"
+      - "System.Half PeekHalf()"
+      - "float PeekSingle()"
+      - "double PeekDouble()"
+      - "string PeekString()"
+      - "int PeekStringSize()"
+      - "bool ReadBoolean()"
+      - "byte ReadByte()"
+      - "bool ReadByte(ref byte)"
+      - "sbyte ReadSByte()"
+      - "byte ReadByte(int)"
+      - "System.Span`1<byte> ReadBytes(System.Span`1<byte>)"
+      - "byte[] ReadBytes(int)"
+      - "bool ReadBytes(int, ref byte[])"
+      - "bool TryReadBytes(System.Span`1<byte>)"
+      - "void ReadBytes(byte[], int, int)"
+      - "void ReadBits(System.Span`1<byte>, int)"
+      - "void ReadBits(byte[], int, int)"
+      - "short ReadInt16()"
+      - "ushort ReadUInt16()"
+      - "int ReadInt32()"
+      - "bool ReadInt32(ref int)"
+      - "int ReadInt32(int)"
+      - "uint ReadUInt32()"
+      - "bool ReadUInt32(ref uint)"
+      - "uint ReadUInt32(int)"
+      - "ulong ReadUInt64()"
+      - "long ReadInt64()"
+      - "ulong ReadUInt64(int)"
+      - "long ReadInt64(int)"
+      - "float ReadFloat()"
+      - "System.Half ReadHalf()"
+      - "float ReadSingle()"
+      - "bool ReadSingle(ref float)"
+      - "double ReadDouble()"
+      - "uint ReadVariableUInt32()"
+      - "bool ReadVariableUInt32(ref uint)"
+      - "int ReadVariableInt32()"
+      - "long ReadVariableInt64()"
+      - "ulong ReadVariableUInt64()"
+      - "float ReadSignedSingle(int)"
+      - "float ReadUnitSingle(int)"
+      - "float ReadRangedSingle(float, float, int)"
+      - "int ReadRangedInteger(int, int)"
+      - "long ReadRangedInteger(long, long)"
+      - "string ReadString()"
+      - "bool ReadString(ref string)"
+      - "double ReadTime(Lidgren.Network.NetConnection, bool)"
+      - "System.Net.IPEndPoint ReadIPEndPoint()"
+      - "void SkipPadBits()"
+      - "void ReadPadBits()"
+      - "void SkipPadBits(int)"
+      - "void EnsureBufferSize(int)"
+      - "void Write(bool)"
+      - "void Write(byte)"
+      - "void WriteAt(int, byte)"
+      - "void Write(sbyte)"
+      - "void Write(byte, int)"
+      - "void Write(byte[])"
+      - "void Write(System.ReadOnlySpan`1<byte>)"
+      - "void Write(byte[], int, int)"
+      - "void Write(ushort)"
+      - "void WriteAt(int, ushort)"
+      - "void Write(ushort, int)"
+      - "void Write(short)"
+      - "void WriteAt(int, short)"
+      - "void Write(int)"
+      - "void WriteAt(int, int)"
+      - "void Write(uint)"
+      - "void WriteAt(int, uint)"
+      - "void Write(uint, int)"
+      - "void Write(int, int)"
+      - "void Write(ulong)"
+      - "void WriteAt(int, ulong)"
+      - "void Write(ulong, int)"
+      - "void Write(long)"
+      - "void Write(long, int)"
+      - "void Write(System.Half)"
+      - "void Write(float)"
+      - "void Write(double)"
+      - "int WriteVariableUInt32(uint)"
+      - "int WriteVariableInt32(int)"
+      - "int WriteVariableInt64(long)"
+      - "int WriteVariableUInt64(ulong)"
+      - "void WriteSignedSingle(float, int)"
+      - "void WriteUnitSingle(float, int)"
+      - "void WriteRangedSingle(float, float, float, int)"
+      - "int WriteRangedInteger(int, int, int)"
+      - "int WriteRangedInteger(long, long, long)"
+      - "void Write(string)"
+      - "void Write(System.Net.IPEndPoint)"
+      - "void WriteTime(bool)"
+      - "void WriteTime(double, bool)"
+      - "void WritePadBits()"
+      - "void WritePadBits(int)"
+      - "void Write(Lidgren.Network.NetBuffer)"
+      - "void Zero(int)"
+      - "void .ctor()"
     NetDeliveryMethod: { }
     NetIncomingMessage:
-      All: True
+      Methods:
+      - "Lidgren.Network.NetIncomingMessageType get_MessageType()"
+      - "Lidgren.Network.NetDeliveryMethod get_DeliveryMethod()"
+      - "int get_SequenceChannel()"
+      - "System.Net.IPEndPoint get_SenderEndPoint()"
+      - "Lidgren.Network.NetConnection get_SenderConnection()"
+      - "double get_ReceiveTime()"
+      - "double ReadTime(bool)"
+      - "string ToString()"
     NetOutgoingMessage:
-      All: True
+      Methods:
+      - "string ToString()"
   Nett:
     CommentLocation: { } # Enum
     Toml:
@@ -951,7 +1085,9 @@ Types:
     IComparable: { All: True }
     IComparable`1: { All: True }
     IDisposable: { All: True }
-    IEquatable`1: { }
+    IEquatable`1:
+      Methods:
+      - "bool Equals(!0)"
     IFormatProvider: { All: True }
     IFormattable: { All: True }
     Index: { All: True }

Robust.Shared/ContentPack/WritableDirProvider.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.Threading;
 using Robust.Shared.Utility;
 
 namespace Robust.Shared.ContentPack
@@ -135,11 +136,37 @@ namespace Robust.Shared.ContentPack
                 path = path.Directory;
 
             var fullPath = GetFullPath(path);
-            Process.Start(new ProcessStartInfo
+            if (OperatingSystem.IsWindows())
             {
-                UseShellExecute = true,
-                FileName = fullPath,
-            });
+                Process.Start(new ProcessStartInfo
+                {
+                    FileName = "explorer.exe",
+                    Arguments = ".",
+                    WorkingDirectory = fullPath,
+                });
+            }
+            else if (OperatingSystem.IsMacOS())
+            {
+                Process.Start(new ProcessStartInfo
+                {
+                    FileName = "open",
+                    Arguments = ".",
+                    WorkingDirectory = fullPath,
+                });
+            }
+            else if (OperatingSystem.IsLinux() || OperatingSystem.IsFreeBSD())
+            {
+                Process.Start(new ProcessStartInfo
+                {
+                    FileName = "xdg-open",
+                    Arguments = ".",
+                    WorkingDirectory = fullPath,
+                });
+            }
+            else
+            {
+                throw new NotSupportedException("Opening OS windows not supported on this OS");
+            }
         }
 
         #endregion

Robust.Shared/GameObjects/Components/Renderable/SpriteLayerData.cs

@@ -29,9 +29,50 @@ public sealed partial class PrototypeLayerData
     [DataField("map")] public HashSet<string>? MapKeys;
     [DataField("renderingStrategy")] public LayerRenderingStrategy? RenderingStrategy;
 
+    /// <summary>
+    /// If set, indicates that this sprite layer should instead be used to copy into shader parameters on another layer.
+    /// </summary>
+    /// <remarks>
+    /// <para>
+    /// If set, this sprite layer is not rendered. Instead, the "result" of rendering it (exact sprite layer and such)
+    /// are copied into the shader parameters of another object,
+    /// specified by the <see cref="PrototypeCopyToShaderParameters"/>.
+    /// </para>
+    /// <para>
+    /// The specified layer must have a shader set. When it does, the shader's
+    /// </para>
+    /// <para>
+    /// Note that sprite layers are processed in-order, so to avoid 1-frame delays,
+    /// the layer doing the copying should occur BEFORE the layer being copied into.
+    /// </para>
+    /// </remarks>
+    [DataField] public PrototypeCopyToShaderParameters? CopyToShaderParameters;
+
     [DataField] public bool Cycle;
 }
 
+/// <summary>
+/// Stores parameters for <see cref="PrototypeLayerData.CopyToShaderParameters"/>.
+/// </summary>
+[Serializable, NetSerializable, DataDefinition]
+public sealed partial class PrototypeCopyToShaderParameters
+{
+    /// <summary>
+    /// The map key of the layer that will have its shader modified.
+    /// </summary>
+    [DataField(required: true)] public string LayerKey;
+
+    /// <summary>
+    /// The name of the shader parameter that will receive the actual selected texture.
+    /// </summary>
+    [DataField] public string? ParameterTexture;
+
+    /// <summary>
+    /// The name of the shader parameter that will receive UVs to select the sprite in <see cref="ParameterTexture"/>.
+    /// </summary>
+    [DataField] public string? ParameterUV;
+}
+
 [Serializable, NetSerializable]
 public enum LayerRenderingStrategy
 {

Robust.Shared/GameObjects/Components/Transform/TransformComponent.cs

@@ -101,7 +101,6 @@ namespace Robust.Shared.GameObjects
         internal bool _mapIdInitialized;
         internal bool _gridInitialized;
 
-        // TODO: Cache this.
         /// <summary>
         ///     The EntityUid of the map which this object is on, if any.
         /// </summary>

Robust.Shared/GameObjects/Components/UserInterface/BoundUserInterface.cs

@@ -41,14 +41,14 @@ namespace Robust.Shared.GameObjects
         /// <summary>
         ///     Invoked when the server uses <c>SetState</c>.
         /// </summary>
-        protected virtual void UpdateState(BoundUserInterfaceState state)
+        protected internal virtual void UpdateState(BoundUserInterfaceState state)
         {
         }
 
         /// <summary>
         ///     Invoked when the server sends an arbitrary message.
         /// </summary>
-        protected virtual void ReceiveMessage(BoundUserInterfaceMessage message)
+        protected internal virtual void ReceiveMessage(BoundUserInterfaceMessage message)
         {
         }
 
@@ -57,7 +57,7 @@ namespace Robust.Shared.GameObjects
         /// </summary>
         public void Close()
         {
-            UiSystem.TryCloseUi(_playerManager.LocalSession, Owner, UiKey);
+            UiSystem.CloseUi(Owner, UiKey, _playerManager.LocalEntity, predicted: true);
         }
 
         /// <summary>
@@ -65,7 +65,7 @@ namespace Robust.Shared.GameObjects
         /// </summary>
         public void SendMessage(BoundUserInterfaceMessage message)
         {
-            UiSystem.SendUiMessage(this, message);
+            UiSystem.ClientSendUiMessage(Owner, UiKey, message);
         }
 
         public void SendPredictedMessage(BoundUserInterfaceMessage message)
@@ -73,20 +73,6 @@ namespace Robust.Shared.GameObjects
             UiSystem.SendPredictedUiMessage(this, message);
         }
 
-        internal void InternalReceiveMessage(BoundUserInterfaceMessage message)
-        {
-            switch (message)
-            {
-                case UpdateBoundStateMessage updateBoundStateMessage:
-                    State = updateBoundStateMessage.State;
-                    UpdateState(State);
-                    break;
-                default:
-                    ReceiveMessage(message);
-                    break;
-            }
-        }
-
         ~BoundUserInterface()
         {
             Dispose(false);

Robust.Shared/GameObjects/Components/UserInterface/IgnoreUIRangeComponent.cs

@@ -1,12 +1,12 @@
-using Robust.Shared.GameObjects;
+using Robust.Shared.GameStates;
 
-namespace Robust.Server.GameObjects;
+namespace Robust.Shared.GameObjects;
 
 /// <summary>
 ///     Lets any entities with this component ignore user interface range checks that would normally
 ///     close the UI automatically.
 /// </summary>
-[RegisterComponent]
+[RegisterComponent, NetworkedComponent]
 public sealed partial class IgnoreUIRangeComponent : Component
 {
 }

Robust.Shared/GameObjects/Components/UserInterface/PlayerBoundUserInterface.cs

@@ -1,53 +0,0 @@
-using System;
-using System.Collections.Generic;
-using JetBrains.Annotations;
-using Robust.Shared.Player;
-using Robust.Shared.ViewVariables;
-
-namespace Robust.Shared.GameObjects;
-
-/// <summary>
-///     Represents an entity-bound interface that can be opened by multiple players at once.
-/// </summary>
-[PublicAPI]
-public sealed class PlayerBoundUserInterface
-{
-    [ViewVariables]
-    public float InteractionRange;
-
-    [ViewVariables]
-    public float InteractionRangeSqrd => InteractionRange * InteractionRange;
-
-    [ViewVariables]
-    public Enum UiKey { get; }
-    [ViewVariables]
-    public EntityUid Owner { get; }
-
-    internal readonly HashSet<ICommonSession> _subscribedSessions = new();
-    [ViewVariables]
-    internal BoundUIWrapMessage? LastStateMsg;
-    [ViewVariables(VVAccess.ReadWrite)]
-    public bool RequireInputValidation;
-
-    [ViewVariables]
-    internal bool StateDirty;
-
-    [ViewVariables]
-    internal readonly Dictionary<ICommonSession, BoundUIWrapMessage> PlayerStateOverrides =
-        new();
-
-    /// <summary>
-    ///     All of the sessions currently subscribed to this UserInterface.
-    /// </summary>
-    [ViewVariables]
-    public IReadOnlySet<ICommonSession> SubscribedSessions => _subscribedSessions;
-
-    public PlayerBoundUserInterface(PrototypeData data, EntityUid owner)
-    {
-        RequireInputValidation = data.RequireInputValidation;
-        UiKey = data.UiKey;
-        Owner = owner;
-
-        InteractionRange = data.InteractionRange;
-    }
-}

Robust.Shared/GameObjects/Components/UserInterface/ServerBoundUserInterfaceMessage.cs

@@ -1,29 +1,26 @@
-using System.Collections.Generic;
 using JetBrains.Annotations;
+using Robust.Shared.GameStates;
 using Robust.Shared.Player;
 using Robust.Shared.ViewVariables;
 
-namespace Robust.Shared.GameObjects
+namespace Robust.Shared.GameObjects;
+
+[RegisterComponent, NetworkedComponent]
+public sealed partial class ActiveUserInterfaceComponent : Component
 {
-    [RegisterComponent]
-    public sealed partial class ActiveUserInterfaceComponent : Component
-    {
-        [ViewVariables]
-        public HashSet<PlayerBoundUserInterface> Interfaces = new();
-    }
+}
 
-    [PublicAPI]
-    public sealed class ServerBoundUserInterfaceMessage
-    {
-        [ViewVariables]
-        public BoundUserInterfaceMessage Message { get; }
-        [ViewVariables]
-        public ICommonSession Session { get; }
+[PublicAPI]
+public sealed class ServerBoundUserInterfaceMessage
+{
+    [ViewVariables]
+    public BoundUserInterfaceMessage Message { get; }
+    [ViewVariables]
+    public ICommonSession Session { get; }
 
-        public ServerBoundUserInterfaceMessage(BoundUserInterfaceMessage message, ICommonSession session)
-        {
-            Message = message;
-            Session = session;
-        }
+    public ServerBoundUserInterfaceMessage(BoundUserInterfaceMessage message, ICommonSession session)
+    {
+        Message = message;
+        Session = session;
     }
 }

Robust.Shared/GameObjects/Components/UserInterface/UserInterfaceComponent.cs

@@ -8,36 +8,51 @@ using Robust.Shared.ViewVariables;
 
 namespace Robust.Shared.GameObjects
 {
-    [RegisterComponent, NetworkedComponent]
+    [RegisterComponent, NetworkedComponent, Access(typeof(SharedUserInterfaceSystem))]
     public sealed partial class UserInterfaceComponent : Component
     {
-        // TODO: Obviously clean this shit up, I just moved it into shared.
+        /// <summary>
+        /// The currently open interfaces. Used clientside to store the UI.
+        /// </summary>
+        [ViewVariables, Access(Friend = AccessPermissions.ReadWriteExecute, Other = AccessPermissions.ReadWriteExecute)]
+        public readonly Dictionary<Enum, BoundUserInterface> ClientOpenInterfaces = new();
 
-        [ViewVariables] public readonly Dictionary<Enum, BoundUserInterface> OpenInterfaces = new();
-
-        [ViewVariables] public readonly Dictionary<Enum, PlayerBoundUserInterface> Interfaces = new();
-
-        public Dictionary<Enum, PrototypeData> MappedInterfaceData = new();
+        [DataField]
+        internal Dictionary<Enum, InterfaceData> Interfaces = new();
 
         /// <summary>
-        /// Loaded on Init from serialized data.
+        /// Actors that currently have interfaces open.
         /// </summary>
-        [DataField("interfaces")] internal List<PrototypeData> InterfaceData = new();
+        [DataField]
+        public Dictionary<Enum, List<EntityUid>> Actors = new();
+
+        /// <summary>
+        /// Legacy data, new BUIs should be using comp states.
+        /// </summary>
+        public Dictionary<Enum, BoundUserInterfaceState> States = new();
+
+        [Serializable, NetSerializable]
+        internal sealed class UserInterfaceComponentState(
+            Dictionary<Enum, List<NetEntity>> actors,
+            Dictionary<Enum, BoundUserInterfaceState> states)
+            : IComponentState
+        {
+            public Dictionary<Enum, List<NetEntity>> Actors = actors;
+
+            public Dictionary<Enum, BoundUserInterfaceState> States = states;
+        }
     }
 
     [DataDefinition]
-    public sealed partial class PrototypeData
+    public sealed partial class InterfaceData
     {
-        [DataField("key", required: true)]
-        public Enum UiKey { get; private set; } = default!;
-
         [DataField("type", required: true)]
         public string ClientType { get; private set; } = default!;
 
         /// <summary>
         ///     Maximum range before a BUI auto-closes. A non-positive number means there is no limit.
         /// </summary>
-        [DataField("range")]
+        [DataField]
         public float InteractionRange = 2f;
 
         // TODO BUI move to content?
@@ -48,7 +63,7 @@ namespace Robust.Shared.GameObjects
         /// <remarks>
         ///     Avoids requiring each system to individually validate client inputs. However, perhaps some BUIs are supposed to be bypass accessibility checks
         /// </remarks>
-        [DataField("requireInputValidation")]
+        [DataField]
         public bool RequireInputValidation = true;
     }
 
@@ -56,18 +71,12 @@ namespace Robust.Shared.GameObjects
     ///     Raised whenever the server receives a BUI message from a client relating to a UI that requires input
     ///     validation.
     /// </summary>
-    public sealed class BoundUserInterfaceMessageAttempt : CancellableEntityEventArgs
+    public sealed class BoundUserInterfaceMessageAttempt(EntityUid actor, EntityUid target, Enum uiKey)
+        : CancellableEntityEventArgs
     {
-        public readonly ICommonSession Sender;
-        public readonly EntityUid Target;
-        public readonly Enum UiKey;
-
-        public BoundUserInterfaceMessageAttempt(ICommonSession sender, EntityUid target, Enum uiKey)
-        {
-            Sender = sender;
-            Target = target;
-            UiKey = uiKey;
-        }
+        public readonly EntityUid Actor = actor;
+        public readonly EntityUid Target = target;
+        public readonly Enum UiKey = uiKey;
     }
 
     [NetSerializable, Serializable]
@@ -104,7 +113,7 @@ namespace Robust.Shared.GameObjects
         ///     Only set when the message is raised as a directed event.
         /// </summary>
         [NonSerialized]
-        public ICommonSession Session = default!;
+        public EntityUid Actor = default!;
     }
 
     /// <summary>
@@ -120,17 +129,6 @@ namespace Robust.Shared.GameObjects
         public NetEntity Entity { get; set; } = NetEntity.Invalid;
     }
 
-    [NetSerializable, Serializable]
-    internal sealed class UpdateBoundStateMessage : BoundUserInterfaceMessage
-    {
-        public readonly BoundUserInterfaceState State;
-
-        public UpdateBoundStateMessage(BoundUserInterfaceState state)
-        {
-            State = state;
-        }
-    }
-
     [NetSerializable, Serializable]
     internal sealed class OpenBoundInterfaceMessage : BoundUserInterfaceMessage
     {
@@ -142,59 +140,38 @@ namespace Robust.Shared.GameObjects
     }
 
     [Serializable, NetSerializable]
-    internal abstract class BaseBoundUIWrapMessage : EntityEventArgs
+    internal abstract class BaseBoundUIWrapMessage(NetEntity entity, BoundUserInterfaceMessage message, Enum uiKey)
+        : EntityEventArgs
     {
-        public readonly NetEntity Entity;
-        public readonly BoundUserInterfaceMessage Message;
-        public readonly Enum UiKey;
-
-        public BaseBoundUIWrapMessage(NetEntity entity, BoundUserInterfaceMessage message, Enum uiKey)
-        {
-            Message = message;
-            UiKey = uiKey;
-            Entity = entity;
-        }
+        public readonly NetEntity Entity = entity;
+        public readonly BoundUserInterfaceMessage Message = message;
+        public readonly Enum UiKey = uiKey;
     }
 
     /// <summary>
     /// Helper message raised from client to server.
     /// </summary>
     [Serializable, NetSerializable]
-    internal sealed class BoundUIWrapMessage : BaseBoundUIWrapMessage
-    {
-        public BoundUIWrapMessage(NetEntity entity, BoundUserInterfaceMessage message, Enum uiKey) : base(entity, message, uiKey)
-        {
-        }
-    }
-
-    /// <summary>
-    /// Helper message raised from client to server.
-    /// </summary>
-    [Serializable, NetSerializable]
-    internal sealed class PredictedBoundUIWrapMessage : BaseBoundUIWrapMessage
-    {
-        public PredictedBoundUIWrapMessage(NetEntity entity, BoundUserInterfaceMessage message, Enum uiKey) : base(entity, message, uiKey)
-        {
-        }
-    }
+    internal sealed class BoundUIWrapMessage(NetEntity entity, BoundUserInterfaceMessage message, Enum uiKey)
+        : BaseBoundUIWrapMessage(entity, message, uiKey);
 
     public sealed class BoundUIOpenedEvent : BaseLocalBoundUserInterfaceEvent
     {
-        public BoundUIOpenedEvent(Enum uiKey, EntityUid uid, ICommonSession session)
+        public BoundUIOpenedEvent(Enum uiKey, EntityUid uid, EntityUid actor)
         {
             UiKey = uiKey;
             Entity = uid;
-            Session = session;
+            Actor = actor;
         }
     }
 
     public sealed class BoundUIClosedEvent : BaseLocalBoundUserInterfaceEvent
     {
-        public BoundUIClosedEvent(Enum uiKey, EntityUid uid, ICommonSession session)
+        public BoundUIClosedEvent(Enum uiKey, EntityUid uid, EntityUid actor)
         {
             UiKey = uiKey;
             Entity = uid;
-            Session = session;
+            Actor = actor;
         }
     }
 }

Robust.Shared/GameObjects/Components/UserInterface/UserInterfaceUserComponent.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using Robust.Shared.GameStates;
+using Robust.Shared.Serialization;
+using Robust.Shared.Serialization.Manager.Attributes;
+
+namespace Robust.Shared.GameObjects;
+
+/// <summary>
+/// Stores data about this entity and what BUIs they have open.
+/// </summary>
+[RegisterComponent, NetworkedComponent]
+public sealed partial class UserInterfaceUserComponent : Component
+{
+    public override bool SessionSpecific => true;
+
+    [DataField]
+    public Dictionary<EntityUid, List<Enum>> OpenInterfaces = new();
+}
+
+[Serializable, NetSerializable]
+internal sealed class UserInterfaceUserComponentState : IComponentState
+{
+    public Dictionary<NetEntity, List<Enum>> OpenInterfaces = new();
+}

Robust.Shared/GameObjects/EntityManager.Components.cs

@@ -1013,6 +1013,11 @@ namespace Robust.Shared.GameObjects
             }
         }
 
+        /// <summary>
+        /// Internal variant of <see cref="GetComponents"/> that directly returns the actual component set.
+        /// </summary>
+        internal IReadOnlyCollection<IComponent> GetComponentsInternal(EntityUid uid) => _entCompIndex[uid];
+
         /// <inheritdoc />
         public int ComponentCount(EntityUid uid)
         {

Robust.Shared/GameObjects/EntityManager.Spawn.cs

@@ -5,16 +5,17 @@ using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Runtime.CompilerServices;
 using Robust.Shared.Containers;
+using Robust.Shared.Maths;
 
 namespace Robust.Shared.GameObjects;
 
 public partial class EntityManager
 {
-    // This method will soon be marked as obsolete.
+    // This method will soon(TM) be marked as obsolete.
     public EntityUid SpawnEntity(string? protoName, EntityCoordinates coordinates, ComponentRegistry? overrides = null)
         => SpawnAttachedTo(protoName, coordinates, overrides);
 
-    // This method will soon be marked as obsolete.
+    // This method will soon(TM) be marked as obsolete.
     public EntityUid SpawnEntity(string? protoName, MapCoordinates coordinates, ComponentRegistry? overrides = null)
         => Spawn(protoName, coordinates, overrides);
 
@@ -83,12 +84,16 @@ public partial class EntityManager
     }
 
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    public EntityUid Spawn(string? protoName = null, ComponentRegistry? overrides = null)
-        => Spawn(protoName, MapCoordinates.Nullspace, overrides);
-
-    public virtual EntityUid Spawn(string? protoName, MapCoordinates coordinates, ComponentRegistry? overrides = null)
+    public EntityUid Spawn(string? protoName = null, ComponentRegistry? overrides = null, bool doMapInit = true)
     {
-        var entity = CreateEntityUninitialized(protoName, coordinates, overrides);
+        var entity = CreateEntityUninitialized(protoName, MapCoordinates.Nullspace, overrides);
+        InitializeAndStartEntity(entity, doMapInit);
+        return entity;
+    }
+
+    public virtual EntityUid Spawn(string? protoName, MapCoordinates coordinates, ComponentRegistry? overrides = null, Angle rotation = default!)
+    {
+        var entity = CreateEntityUninitialized(protoName, coordinates, overrides, rotation);
         InitializeAndStartEntity(entity, coordinates.MapId);
         return entity;
     }
@@ -111,32 +116,19 @@ public partial class EntityManager
         if (!xform.ParentUid.IsValid())
             return false;
 
-        if (!MetaQuery.TryGetComponent(target, out var meta))
-            return false;
-
-        if ((meta.Flags & MetaDataFlags.InContainer) == 0)
+        if (!_containers.TryGetContainingContainer(target, out var container))
         {
-            uid = SpawnAttachedTo(protoName, xform.Coordinates, overrides);
+            uid = SpawnNextToOrDrop(protoName, target, xform, overrides);
             return true;
         }
 
-        if (!TryGetComponent(xform.ParentUid, out ContainerManagerComponent? containerComp))
-            return false;
-
-        foreach (var container in containerComp.Containers.Values)
-        {
-            if (!container.Contains(target))
-                continue;
-
-            uid = Spawn(protoName, overrides);
-            if (_containers.Insert(uid.Value, container))
-                return true;
-
-            DeleteEntity(uid.Value);
-            uid = null;
-            return false;
-        }
+        var doMapInit = _mapSystem.IsInitialized(xform.MapUid);
+        uid = Spawn(protoName, overrides, doMapInit);
+        if (_containers.Insert(uid.Value, container))
+            return true;
 
+        DeleteEntity(uid.Value);
+        uid = null;
         return false;
     }
 
@@ -155,7 +147,8 @@ public partial class EntityManager
         if (!containerComp.Containers.TryGetValue(containerId, out var container))
             return false;
 
-        uid = Spawn(protoName, overrides);
+        var doMapInit = _mapSystem.IsInitialized(TransformQuery.GetComponent(containerUid).MapUid);
+        uid = Spawn(protoName, overrides, doMapInit);
 
         if (_containers.Insert(uid.Value, container))
             return true;
@@ -171,7 +164,8 @@ public partial class EntityManager
         if (!xform.ParentUid.IsValid())
             return Spawn(protoName);
 
-        var uid = Spawn(protoName, overrides);
+        var doMapInit = _mapSystem.IsInitialized(xform.MapUid);
+        var uid = Spawn(protoName, overrides, doMapInit);
         _xforms.DropNextTo(uid, target);
         return uid;
     }
@@ -184,14 +178,28 @@ public partial class EntityManager
         ContainerManagerComponent? containerComp = null,
         ComponentRegistry? overrides = null)
     {
-        var uid = Spawn(protoName, overrides);
+        return SpawnInContainerOrDrop(protoName, containerUid, containerId, out _, xform, containerComp, overrides);
+    }
+
+    public EntityUid SpawnInContainerOrDrop(
+        string? protoName,
+        EntityUid containerUid,
+        string containerId,
+        out bool inserted,
+        TransformComponent? xform = null,
+        ContainerManagerComponent? containerComp = null,
+        ComponentRegistry? overrides = null)
+    {
+        inserted = true;
+        xform ??= TransformQuery.GetComponent(containerUid);
+        var doMapInit = _mapSystem.IsInitialized(xform.MapUid);
+        var uid = Spawn(protoName, overrides, doMapInit);
 
         if ((containerComp == null && !TryGetComponent(containerUid, out containerComp))
              || !containerComp.Containers.TryGetValue(containerId, out var container)
              || !_containers.Insert(uid, container))
         {
-
-            xform ??= TransformQuery.GetComponent(containerUid);
+            inserted = false;
             if (xform.ParentUid.IsValid())
                 _xforms.DropNextTo(uid, (containerUid, xform));
         }

Robust.Shared/GameObjects/EntityManager.cs

@@ -9,6 +9,7 @@ using Robust.Shared.GameStates;
 using Robust.Shared.Log;
 using Robust.Shared.Map;
 using Robust.Shared.Map.Components;
+using Robust.Shared.Maths;
 using Robust.Shared.Network;
 using Robust.Shared.Player;
 using Robust.Shared.Profiling;
@@ -297,14 +298,13 @@ namespace Robust.Shared.GameObjects
         }
 
         /// <inheritdoc />
-        public virtual EntityUid CreateEntityUninitialized(string? prototypeName, MapCoordinates coordinates, ComponentRegistry? overrides = null)
+        public virtual EntityUid CreateEntityUninitialized(string? prototypeName, MapCoordinates coordinates, ComponentRegistry? overrides = null, Angle rotation = default!)
         {
             var newEntity = CreateEntity(prototypeName, out _, overrides);
             var transform = TransformQuery.GetComponent(newEntity);
 
             if (coordinates.MapId == MapId.Nullspace)
             {
-                DebugTools.Assert(_mapManager.GetMapEntityId(coordinates.MapId) == EntityUid.Invalid);
                 transform._parent = EntityUid.Invalid;
                 transform.Anchored = false;
                 return newEntity;
@@ -323,7 +323,7 @@ namespace Robust.Shared.GameObjects
             else
             {
                 coords = new EntityCoordinates(mapEnt, coordinates.Position);
-                _xforms.SetCoordinates(newEntity, transform, coords, null, newParent: mapXform);
+                _xforms.SetCoordinates(newEntity, transform, coords, rotation, newParent: mapXform);
             }
 
             return newEntity;
@@ -776,7 +776,7 @@ namespace Robust.Shared.GameObjects
         /// <summary>
         ///     Allocates an entity and loads components but does not do initialization.
         /// </summary>
-        private protected virtual EntityUid CreateEntity(string? prototypeName, out MetaDataComponent metadata, IEntityLoadContext? context = null)
+        internal virtual EntityUid CreateEntity(string? prototypeName, out MetaDataComponent metadata, IEntityLoadContext? context = null)
         {
             if (prototypeName == null)
                 return AllocEntity(out metadata);
@@ -821,15 +821,22 @@ namespace Robust.Shared.GameObjects
 
         public void InitializeAndStartEntity(EntityUid entity, MapId? mapId = null)
         {
+            var doMapInit = _mapManager.IsMapInitialized(mapId ?? TransformQuery.GetComponent(entity).MapID);
+            InitializeAndStartEntity(entity, doMapInit);
+        }
+
+        public void InitializeAndStartEntity(Entity<MetaDataComponent?> entity, bool doMapInit)
+        {
+            if (!MetaQuery.Resolve(entity.Owner, ref entity.Comp))
+                return;
+
             try
             {
-                var meta = MetaQuery.GetComponent(entity);
-                InitializeEntity(entity, meta);
-                StartEntity(entity);
+                InitializeEntity(entity.Owner, entity.Comp);
+                StartEntity(entity.Owner);
 
-                // If the map we're initializing the entity on is initialized, run map init on it.
-                if (_mapManager.IsMapInitialized(mapId ?? TransformQuery.GetComponent(entity).MapID))
-                    RunMapInit(entity, meta);
+                if (doMapInit)
+                    RunMapInit(entity.Owner, entity.Comp);
             }
             catch (Exception e)
             {
@@ -859,7 +866,7 @@ namespace Robust.Shared.GameObjects
             DebugTools.Assert(meta.EntityLifeStage == EntityLifeStage.Initialized, $"Expected entity {ToPrettyString(entity)} to be initialized, was {meta.EntityLifeStage}");
             SetLifeStage(meta, EntityLifeStage.MapInitialized);
 
-            EventBus.RaiseLocalEvent(entity, MapInitEventInstance, false);
+            EventBus.RaiseLocalEvent(entity, MapInitEventInstance);
         }
 
         /// <inheritdoc />

Robust.Shared/GameObjects/EntityManagerExt.cs

@@ -1,4 +1,7 @@
-namespace Robust.Shared.GameObjects
+using Robust.Shared.Collections;
+using Robust.Shared.Random;
+
+namespace Robust.Shared.GameObjects
 {
     public static class EntityManagerExt
     {
@@ -19,5 +22,79 @@
 
             return default;
         }
+
+        /// <summary>
+        /// Picks an entity at random with the supplied component.
+        /// </summary>
+        public static bool TryGetRandom<TComp1>(this IEntityManager entManager, IRobustRandom random, out EntityUid entity, bool includePaused = false) where TComp1 : IComponent
+        {
+            var entities = new ValueList<EntityUid>();
+
+            if (includePaused)
+            {
+                var query = entManager.AllEntityQueryEnumerator<TComp1>();
+
+                while (query.MoveNext(out var uid, out _))
+                {
+                    entities.Add(uid);
+                }
+            }
+            else
+            {
+                var query = entManager.EntityQueryEnumerator<TComp1>();
+
+                while (query.MoveNext(out var uid, out _))
+                {
+                    entities.Add(uid);
+                }
+            }
+
+            if (entities.Count == 0)
+            {
+                entity = EntityUid.Invalid;
+                return false;
+            }
+
+            entity = random.Pick(entities);
+            return true;
+        }
+
+        /// <summary>
+        /// Picks an entity at random with the supplied components.
+        /// </summary>
+        public static bool TryGetRandom<TComp1, TComp2>(this IEntityManager entManager, IRobustRandom random, out EntityUid entity, bool includePaused = false)
+            where TComp1 : IComponent
+            where TComp2 : IComponent
+        {
+            var entities = new ValueList<EntityUid>();
+
+            if (includePaused)
+            {
+                var query = entManager.AllEntityQueryEnumerator<TComp1, TComp2>();
+
+                while (query.MoveNext(out var uid, out _, out _))
+                {
+                    entities.Add(uid);
+                }
+            }
+            else
+            {
+                var query = entManager.EntityQueryEnumerator<TComp1, TComp2>();
+
+                while (query.MoveNext(out var uid, out _, out _))
+                {
+                    entities.Add(uid);
+                }
+            }
+
+            if (entities.Count == 0)
+            {
+                entity = EntityUid.Invalid;
+                return false;
+            }
+
+            entity = random.Pick(entities);
+            return true;
+        }
     }
 }

Robust.Shared/GameObjects/EntitySystem.Proxy.cs

@@ -5,8 +5,10 @@ using System.Runtime.CompilerServices;
 using JetBrains.Annotations;
 using Robust.Shared.Containers;
 using Robust.Shared.Map;
+using Robust.Shared.Maths;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Timing;
+using TerraFX.Interop.Windows;
 
 namespace Robust.Shared.GameObjects;
 
@@ -699,32 +701,32 @@ public partial class EntitySystem
 
     #region Entity Spawning
 
-    // This method will be obsoleted soon.
+    // This method will be obsoleted soon(TM).
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
     protected EntityUid Spawn(string? prototype, EntityCoordinates coordinates)
     {
         return ((IEntityManager)EntityManager).SpawnEntity(prototype, coordinates);
     }
 
-    /// <inheritdoc cref="IEntityManager.Spawn(string?, MapCoordinates, ComponentRegistry?)" />
+    /// <inheritdoc cref="IEntityManager.Spawn(string?, MapCoordinates, ComponentRegistry?, Angle)" />
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    protected EntityUid Spawn(string? prototype, MapCoordinates coordinates)
-        => EntityManager.Spawn(prototype, coordinates);
+    protected EntityUid Spawn(string? prototype, MapCoordinates coordinates, ComponentRegistry? overrides = null, Angle rotation = default)
+        => EntityManager.Spawn(prototype, coordinates, overrides, rotation);
 
-    /// <inheritdoc cref="IEntityManager.Spawn(string?, ComponentRegistry?)" />
+    /// <inheritdoc cref="IEntityManager.Spawn(string?, ComponentRegistry?, bool)" />
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    protected EntityUid Spawn(string? prototype = null)
-        => EntityManager.Spawn(prototype);
+    protected EntityUid Spawn(string? prototype = null, ComponentRegistry? overrides = null, bool doMapInit = true)
+        => EntityManager.Spawn(prototype, overrides, doMapInit);
 
     /// <inheritdoc cref="IEntityManager.SpawnAttachedTo" />
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    protected EntityUid SpawnAttachedTo(string? prototype, EntityCoordinates coordinates)
-        => EntityManager.SpawnAttachedTo(prototype, coordinates);
+    protected EntityUid SpawnAttachedTo(string? prototype, EntityCoordinates coordinates, ComponentRegistry? overrides = null)
+        => EntityManager.SpawnAttachedTo(prototype, coordinates, overrides);
 
     /// <inheritdoc cref="IEntityManager.SpawnAtPosition" />
     [MethodImpl(MethodImplOptions.AggressiveInlining)]
-    protected EntityUid SpawnAtPosition(string? prototype, EntityCoordinates coordinates)
-        => EntityManager.SpawnAtPosition(prototype, coordinates);
+    protected EntityUid SpawnAtPosition(string? prototype, EntityCoordinates coordinates, ComponentRegistry? overrides = null)
+        => EntityManager.SpawnAtPosition(prototype, coordinates, overrides);
 
     /// <inheritdoc cref="IEntityManager.TrySpawnInContainer" />
     [MethodImpl(MethodImplOptions.AggressiveInlining)]

Robust.Shared/GameObjects/IEntityManager.Spawn.cs

@@ -2,6 +2,7 @@ using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using Robust.Shared.Containers;
 using Robust.Shared.Map;
+using Robust.Shared.Maths;
 using Robust.Shared.Prototypes;
 
 namespace Robust.Shared.GameObjects;
@@ -27,12 +28,12 @@ public partial interface IEntityManager
     /// <summary>
     /// Spawns an entity in nullspace.
     /// </summary>
-    EntityUid Spawn(string? protoName = null, ComponentRegistry? overrides = null);
+    EntityUid Spawn(string? protoName = null, ComponentRegistry? overrides = null, bool doMapInit = true);
 
     /// <summary>
     /// Spawns an entity at a specific world position. The entity will either be parented to the map or a grid.
     /// </summary>
-    EntityUid Spawn(string? protoName, MapCoordinates coordinates, ComponentRegistry? overrides = null);
+    EntityUid Spawn(string? protoName, MapCoordinates coordinates, ComponentRegistry? overrides = null, Angle rotation = default!);
 
     /// <summary>
     /// Spawns an entity and then parents it to the entity that the given entity coordinates are relative to.
@@ -46,7 +47,7 @@ public partial interface IEntityManager
     EntityUid SpawnAtPosition(string? protoName, EntityCoordinates coordinates, ComponentRegistry? overrides = null);
 
     /// <summary>
-    /// Attempts to spawn an entity inside of a container.
+    /// Attempt to spawn an entity and insert it into a container. If the insertion fails, the entity gets deleted.
     /// </summary>
     bool TrySpawnInContainer(
         string? protoName,
@@ -58,9 +59,9 @@ public partial interface IEntityManager
 
     /// <summary>
     /// Attempts to spawn an entity inside of a container. If it fails to insert into the container, it will
-    /// instead attempt to spawn the entity next to the target.
+    /// instead drop the entity next to the target (see <see cref="SpawnNextToOrDrop"/>).
     /// </summary>
-    public EntityUid SpawnInContainerOrDrop(
+    EntityUid SpawnInContainerOrDrop(
         string? protoName,
         EntityUid containerUid,
         string containerId,
@@ -68,9 +69,20 @@ public partial interface IEntityManager
         ContainerManagerComponent? containerComp = null,
         ComponentRegistry? overrides = null);
 
+    /// <inheritdoc cref="SpawnInContainerOrDrop(string?,Robust.Shared.GameObjects.EntityUid,string,Robust.Shared.GameObjects.TransformComponent?,Robust.Shared.Containers.ContainerManagerComponent?,Robust.Shared.Prototypes.ComponentRegistry?)"/>
+    EntityUid SpawnInContainerOrDrop(
+        string? protoName,
+        EntityUid containerUid,
+        string containerId,
+        out bool inserted,
+        TransformComponent? xform = null,
+        ContainerManagerComponent? containerComp = null,
+        ComponentRegistry? overrides = null);
+
     /// <summary>
-    /// Attempts to spawn an entity adjacent to some other entity. If the other entity is in a container, this will
-    /// attempt to insert the new entity into the same container.
+    /// Attempts to spawn an entity adjacent to some other target entity. If the target entity is in
+    /// a container, this will attempt to insert the spawned entity into the same container. If the insertion fails,
+    /// the entity is deleted. If the entity is not in a container, this behaves like <see cref="SpawnNextToOrDrop"/>.
     /// </summary>
     bool TrySpawnNextTo(
         string? protoName,

Robust.Shared/GameObjects/IEntityManager.cs

@@ -4,6 +4,7 @@ using System.Diagnostics.CodeAnalysis;
 using JetBrains.Annotations;
 using Prometheus;
 using Robust.Shared.Map;
+using Robust.Shared.Maths;
 using Robust.Shared.Prototypes;
 using Robust.Shared.Timing;
 
@@ -76,10 +77,12 @@ namespace Robust.Shared.GameObjects
 
         EntityUid CreateEntityUninitialized(string? prototypeName, EntityCoordinates coordinates, ComponentRegistry? overrides = null);
 
-        EntityUid CreateEntityUninitialized(string? prototypeName, MapCoordinates coordinates, ComponentRegistry? overrides = null);
+        EntityUid CreateEntityUninitialized(string? prototypeName, MapCoordinates coordinates, ComponentRegistry? overrides = null, Angle rotation = default!);
 
         void InitializeAndStartEntity(EntityUid entity, MapId? mapId = null);
 
+        void InitializeAndStartEntity(Entity<MetaDataComponent?> entity, bool doMapInit);
+
         void InitializeEntity(EntityUid entity, MetaDataComponent? meta = null);
 
         void StartEntity(EntityUid entity);