Version: 247.2.5

Apparently NetSerializer treats IDynamicTypeSerializer and IStaticTypeSerializer differently for sealed types??

(cherry-picked from 6bbeaeeba6, without the test changes)

(cherry picked from commit d187018834dfa1cdead9ce5a7b72c38b07f8c81f)

Directory.Packages.props

@@ -57,7 +57,7 @@
     <PackageVersion Include="SharpZstd.Interop" Version="1.5.2-beta2" />
     <PackageVersion Include="SixLabors.ImageSharp" Version="3.1.6" />
     <PackageVersion Include="SpaceWizards.HttpListener" Version="0.1.1" />
-    <PackageVersion Include="SpaceWizards.NFluidsynth" Version="0.1.1" />
+    <PackageVersion Include="SpaceWizards.NFluidsynth" Version="0.2.2" />
     <PackageVersion Include="SpaceWizards.SharpFont" Version="1.0.2" />
     <PackageVersion Include="SpaceWizards.Sodium" Version="0.2.1" />
     <PackageVersion Include="TerraFX.Interop.Windows" Version="10.0.26100.1" />

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 +54,60 @@ END TEMPLATE-->
 *None yet*
 
 
+## 247.2.5
+
+
+## 247.2.4
+
+
+## 247.2.3
+
+
+## 247.2.2
+
+
+## 247.2.1
+
+
+## 247.2.0
+
+### New features
+
+* Added functions for copying components to `IEntityManager` and `EntitySystem`.
+* Sound played from sound collections is now sent as "collection ID + index" over the network instead of the final filename.
+  * This enables integration of future accessibility systems.
+  * Added a new `ResolvedSoundSpecifier` to represent played sounds. Methods that previously took a filename now take a `ResolvedSoundSpecifier`, with an implicit cast from string being interpreted as a raw filename.
+* `VisibilitySystem` has been made accessible to shared as `SharedVisibilitySystem`.
+* `ScrollContainer` now has properties exposing `Value` and `ValueTarget` on its internal scroll bars.
+
+### Bugfixes
+
+* Fix prototype hot reload crashing when adding a new component already exists on an entity.
+* Fix maps failing to save in some cases related to tilemap IDs.
+* Fix `Regex.Escape(string)` not being available in sandbox.
+* Prototypes that parent themselves directly won't cause the game to hang on an infinite loop anymore.
+* Fixed disconnecting during a connection attempt leaving the client stuck in a phantom state.
+
+### Internal
+
+* More warning cleanup.
+
+## 247.1.0
+
+### New features
+
+* Added support for `Color[]` shader uniforms
+* Added optional minimumDistance parameter to `SharedJointSystem.CreateDistanceJoint()`
+
+### Bugfixes
+
+* Fixed `EntitySystem.DirtyFields()` not actually marking fields as dirty.
+
+### Other
+
+* Updated the Yamale map file format validator to support v7 map/grid files.
+
+
 ## 247.0.0
 
 ### Breaking changes
@@ -64,7 +118,7 @@ END TEMPLATE-->
   when warnings are logged.
 * The minimum supported map format / version has been increased from 2 to 3.
 * The server-side `MapLoaderSystem` and associated classes & structs has been moved to `Robust.Shared`, and has been significantly modified.
-  * The`TryLoad` and `Save` methods have been replaced with grid, map, generic entity variants. I.e, `SaveGrid`, `SaveMap`, and `SaveEntities`.
+  * The `TryLoad` and `Save` methods have been replaced with grid, map, generic entity variants. I.e, `SaveGrid`, `SaveMap`, and `SaveEntities`.
   * Most of the serialization logic and methods have been moved out of `MapLoaderSystem` and into new `EntitySerializer`
     and `EntityDeserializer` classes, which also replace the old `MapSerializationContext`.
   * The `MapLoadOptions` class has been split into `MapLoadOptions`, `SerializationOptions`, and `DeserializationOptions`

Robust.Client.WebView/Cef/Program.cs

@@ -6,7 +6,7 @@ using Xilium.CefGlue;
 
 namespace Robust.Client.WebView.Cef
 {
-    public static class Program
+    internal static class Program
     {
         // This was supposed to be the main entry for the subprocess program... It doesn't work.
         public static int Main(string[] args)

Robust.Client.WebView/Cef/WebViewManagerCef.cs

@@ -5,6 +5,7 @@ using System.Net;
 using System.Reflection;
 using System.Text;
 using Robust.Client.Console;
+using Robust.Client.Utility;
 using Robust.Shared.Configuration;
 using Robust.Shared.ContentPack;
 using Robust.Shared.IoC;
@@ -24,6 +25,7 @@ namespace Robust.Client.WebView.Cef
 
         [Dependency] private readonly IDependencyCollection _dependencyCollection = default!;
         [Dependency] private readonly IPrototypeManager _prototypeManager = default!;
+        [Dependency] private readonly IGameControllerInternal _gameController = default!;
         [Dependency] private readonly IResourceManagerInternal _resourceManager = default!;
         [Dependency] private readonly IClientConsoleHost _consoleHost = default!;
         [Dependency] private readonly IConfigurationManager _cfg = default!;
@@ -61,7 +63,10 @@ namespace Robust.Client.WebView.Cef
 
             var cachePath = "";
             if (_resourceManager.UserData is WritableDirProvider userData)
-                cachePath = userData.GetFullPath(new ResPath("/cef_cache"));
+            {
+                var rootDir = UserDataDir.GetRootUserDataDir(_gameController);
+                cachePath = Path.Combine(rootDir, "cef_cache", "0");
+            }
 
             var settings = new CefSettings()
             {

Robust.Client/Animations/AnimationTrackPlaySound.cs

@@ -40,11 +40,7 @@ namespace Robust.Client.Animations
                 var keyFrame = KeyFrames[keyFrameIndex];
 
                 var audioParams = keyFrame.AudioParamsFunc.Invoke();
-                var audio = new SoundPathSpecifier(keyFrame.Resource)
-                {
-                    Params = audioParams
-                };
-                IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<AudioSystem>().PlayEntity(audio, Filter.Local(), entity, true);
+                IoCManager.Resolve<IEntitySystemManager>().GetEntitySystem<AudioSystem>().PlayEntity(keyFrame.Specifier, Filter.Local(), entity, true, audioParams);
             }
 
             return (keyFrameIndex, playingTime);
@@ -55,7 +51,7 @@ namespace Robust.Client.Animations
             /// <summary>
             ///     The RSI state to play when this keyframe gets triggered.
             /// </summary>
-            public readonly string Resource;
+            public readonly ResolvedSoundSpecifier Specifier;
 
             /// <summary>
             ///     A function that returns the audio parameter to be used.
@@ -69,9 +65,9 @@ namespace Robust.Client.Animations
             /// </summary>
             public readonly float KeyTime;
 
-            public KeyFrame(string resource, float keyTime, Func<AudioParams>? audioParams = null)
+            public KeyFrame(ResolvedSoundSpecifier specifier, float keyTime, Func<AudioParams>? audioParams = null)
             {
-                Resource = resource;
+                Specifier = specifier;
                 KeyTime = keyTime;
                 AudioParamsFunc = audioParams ?? (() => AudioParams.Default);
             }

Robust.Client/Audio/AudioSystem.cs

@@ -415,6 +415,16 @@ public sealed partial class AudioSystem : SharedAudioSystem
         return occlusion;
     }
 
+    private bool TryGetAudio(ResolvedSoundSpecifier specifier, [NotNullWhen(true)] out AudioResource? audio)
+    {
+        var filename = GetAudioPath(specifier);
+        if (_resourceCache.TryGetResource(new ResPath(filename), out audio))
+            return true;
+
+        Log.Error($"Server tried to play audio file {filename} which does not exist.");
+        return false;
+    }
+
     private bool TryGetAudio(string filename, [NotNullWhen(true)] out AudioResource? audio)
     {
         if (_resourceCache.TryGetResource(new ResPath(filename), out audio))
@@ -433,15 +443,15 @@ public sealed partial class AudioSystem : SharedAudioSystem
         return false;
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(string? filename, EntityCoordinates coordinates,
+    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? specifier, EntityCoordinates coordinates,
         AudioParams? audioParams = null)
     {
-        return PlayStatic(filename, Filter.Local(), coordinates, true, audioParams);
+        return PlayStatic(specifier, Filter.Local(), coordinates, true, audioParams);
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(string? filename, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? specifier, EntityUid uid, AudioParams? audioParams = null)
     {
-        return PlayEntity(filename, Filter.Local(), uid, true, audioParams);
+        return PlayEntity(specifier, Filter.Local(), uid, true, audioParams);
     }
 
     /// <inheritdoc />
@@ -477,21 +487,21 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="audioParams"></param>
-    private (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, AudioParams? audioParams = null, bool recordReplay = true)
+    private (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? specifier, AudioParams? audioParams = null, bool recordReplay = true)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (recordReplay && _replayRecording.IsRecording)
         {
             _replayRecording.RecordReplayMessage(new PlayAudioGlobalMessage
             {
-                FileName = filename,
+                Specifier = specifier,
                 AudioParams = audioParams ?? AudioParams.Default
             });
         }
 
-        return TryGetAudio(filename, out var audio) ? PlayGlobal(audio, audioParams) : default;
+        return TryGetAudio(specifier, out var audio) ? PlayGlobal(audio, specifier, audioParams) : default;
     }
 
     /// <summary>
@@ -499,9 +509,9 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// </summary>
     /// <param name="stream">The audio stream to play.</param>
     /// <param name="audioParams"></param>
-    public (EntityUid Entity, AudioComponent Component)? PlayGlobal(AudioStream stream, AudioParams? audioParams = null)
+    public (EntityUid Entity, AudioComponent Component)? PlayGlobal(AudioStream stream, ResolvedSoundSpecifier? specifier, AudioParams? audioParams = null)
     {
-        var (entity, component) = CreateAndStartPlayingStream(audioParams, stream);
+        var (entity, component) = CreateAndStartPlayingStream(audioParams, specifier, stream);
         component.Global = true;
         component.Source.Global = true;
         DirtyField(entity, component, nameof(AudioComponent.Global));
@@ -513,22 +523,22 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="entity">The entity "emitting" the audio.</param>
-    private (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, EntityUid entity, AudioParams? audioParams = null, bool recordReplay = true)
+    private (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? specifier, EntityUid entity, AudioParams? audioParams = null, bool recordReplay = true)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (recordReplay && _replayRecording.IsRecording)
         {
             _replayRecording.RecordReplayMessage(new PlayAudioEntityMessage
             {
-                FileName = filename,
+                Specifier = specifier,
                 NetEntity = GetNetEntity(entity),
                 AudioParams = audioParams ?? AudioParams.Default
             });
         }
 
-        return TryGetAudio(filename, out var audio) ? PlayEntity(audio, entity, audioParams) : default;
+        return TryGetAudio(specifier, out var audio) ? PlayEntity(audio, entity, specifier, audioParams) : default;
     }
 
     /// <summary>
@@ -537,7 +547,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// <param name="stream">The audio stream to play.</param>
     /// <param name="entity">The entity "emitting" the audio.</param>
     /// <param name="audioParams"></param>
-    public (EntityUid Entity, AudioComponent Component)? PlayEntity(AudioStream stream, EntityUid entity, AudioParams? audioParams = null)
+    public (EntityUid Entity, AudioComponent Component)? PlayEntity(AudioStream stream, EntityUid entity, ResolvedSoundSpecifier? specifier, AudioParams? audioParams = null)
     {
         if (TerminatingOrDeleted(entity))
         {
@@ -545,7 +555,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
             return null;
         }
 
-        var playing = CreateAndStartPlayingStream(audioParams, stream);
+        var playing = CreateAndStartPlayingStream(audioParams, specifier, stream);
         _xformSys.SetCoordinates(playing.Entity, new EntityCoordinates(entity, Vector2.Zero));
 
         return playing;
@@ -557,22 +567,22 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
     /// <param name="audioParams"></param>
-    private (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, EntityCoordinates coordinates, AudioParams? audioParams = null, bool recordReplay = true)
+    private (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? specifier, EntityCoordinates coordinates, AudioParams? audioParams = null, bool recordReplay = true)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (recordReplay && _replayRecording.IsRecording)
         {
             _replayRecording.RecordReplayMessage(new PlayAudioPositionalMessage
             {
-                FileName = filename,
+                Specifier = specifier,
                 Coordinates = GetNetCoordinates(coordinates),
                 AudioParams = audioParams ?? AudioParams.Default
             });
         }
 
-        return TryGetAudio(filename, out var audio) ? PlayStatic(audio, coordinates, audioParams) : default;
+        return TryGetAudio(specifier, out var audio) ? PlayStatic(audio, coordinates, specifier, audioParams) : default;
     }
 
     /// <summary>
@@ -581,7 +591,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
     /// <param name="stream">The audio stream to play.</param>
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
     /// <param name="audioParams"></param>
-    public (EntityUid Entity, AudioComponent Component)? PlayStatic(AudioStream stream, EntityCoordinates coordinates, AudioParams? audioParams = null)
+    public (EntityUid Entity, AudioComponent Component)? PlayStatic(AudioStream stream, EntityCoordinates coordinates, ResolvedSoundSpecifier? specifier, AudioParams? audioParams = null)
     {
         if (TerminatingOrDeleted(coordinates.EntityId))
         {
@@ -589,33 +599,33 @@ public sealed partial class AudioSystem : SharedAudioSystem
             return null;
         }
 
-        var playing = CreateAndStartPlayingStream(audioParams, stream);
+        var playing = CreateAndStartPlayingStream(audioParams, specifier, stream);
         _xformSys.SetCoordinates(playing.Entity, coordinates);
         return playing;
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? specifier, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null)
     {
-        return PlayGlobal(filename, audioParams);
+        return PlayGlobal(specifier, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, Filter playerFilter, EntityUid entity, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? specifier, Filter playerFilter, EntityUid entity, bool recordReplay, AudioParams? audioParams = null)
     {
-        return PlayEntity(filename, entity, audioParams);
+        return PlayEntity(specifier, entity, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? specifier, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null)
     {
-        return PlayStatic(filename, coordinates, audioParams);
+        return PlayStatic(specifier, coordinates, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, ICommonSession recipient, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? specifier, ICommonSession recipient, AudioParams? audioParams = null)
     {
-        return PlayGlobal(filename, audioParams);
+        return PlayGlobal(specifier, audioParams);
     }
 
     public override void LoadStream<T>(Entity<AudioComponent> entity, T stream)
@@ -629,39 +639,39 @@ public sealed partial class AudioSystem : SharedAudioSystem
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, EntityUid recipient, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? specifier, EntityUid recipient, AudioParams? audioParams = null)
     {
-        return PlayGlobal(filename, audioParams);
+        return PlayGlobal(specifier, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? specifier, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null)
     {
-        return PlayEntity(filename, uid, audioParams);
+        return PlayEntity(specifier, uid, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? specifier, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null)
     {
-        return PlayEntity(filename, uid, audioParams);
+        return PlayEntity(specifier, uid, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? specifier, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
-        return PlayStatic(filename, coordinates, audioParams);
+        return PlayStatic(specifier, coordinates, audioParams);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? specifier, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
-        return PlayStatic(filename, coordinates, audioParams);
+        return PlayStatic(specifier, coordinates, audioParams);
     }
 
-    private (EntityUid Entity, AudioComponent Component) CreateAndStartPlayingStream(AudioParams? audioParams, AudioStream stream)
+    private (EntityUid Entity, AudioComponent Component) CreateAndStartPlayingStream(AudioParams? audioParams, ResolvedSoundSpecifier? specifier, AudioStream stream)
     {
         var audioP = audioParams ?? AudioParams.Default;
-        var entity = SetupAudio(null, audioP, initialize: false, length: stream.Length);
+        var entity = SetupAudio(specifier, audioP, initialize: false, length: stream.Length);
         LoadStream(entity, stream);
         EntityManager.InitializeAndStartEntity(entity);
         var comp = entity.Comp;
@@ -694,17 +704,17 @@ public sealed partial class AudioSystem : SharedAudioSystem
 
     private void OnEntityCoordinates(PlayAudioPositionalMessage ev)
     {
-        PlayStatic(ev.FileName, GetCoordinates(ev.Coordinates), ev.AudioParams, false);
+        PlayStatic(ev.Specifier, GetCoordinates(ev.Coordinates), ev.AudioParams, false);
     }
 
     private void OnEntityAudio(PlayAudioEntityMessage ev)
     {
-        PlayEntity(ev.FileName, GetEntity(ev.NetEntity), ev.AudioParams, false);
+        PlayEntity(ev.Specifier, GetEntity(ev.NetEntity), ev.AudioParams, false);
     }
 
     private void OnGlobalAudio(PlayAudioGlobalMessage ev)
     {
-        PlayGlobal(ev.FileName, ev.AudioParams, false);
+        PlayGlobal(ev.Specifier, ev.AudioParams, false);
     }
 
     protected override TimeSpan GetAudioLengthImpl(string filename)

Robust.Client/BaseClient.cs

@@ -115,10 +115,6 @@ namespace Robust.Client
         /// <inheritdoc />
         public void DisconnectFromServer(string reason)
         {
-            DebugTools.Assert(RunLevel > ClientRunLevel.Initialize);
-            DebugTools.Assert(_net.IsConnected);
-            // run level changed in OnNetDisconnect()
-            // are both of these *really* needed?
             _net.ClientDisconnect(reason);
         }
 

Robust.Client/GameController/GameController.cs

@@ -382,7 +382,7 @@ namespace Robust.Client
 
             _prof.Initialize();
 
-            _resManager.Initialize(Options.LoadConfigAndUserData ? userDataDir : null);
+            _resManager.Initialize(Options.LoadConfigAndUserData ? userDataDir : null, hideUserDataDir: true);
 
             var mountOptions = _commandLineArgs != null
                 ? MountOptions.Merge(_commandLineArgs.MountOptions, Options.MountOptions)

Robust.Client/GameObjects/EntitySystems/VisibilitySystem.cs

@@ -0,0 +1,8 @@
+using Robust.Shared.GameObjects;
+
+namespace Robust.Client.GameObjects;
+
+public sealed class VisibilitySystem : SharedVisibilitySystem
+{
+
+}

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

@@ -523,6 +523,9 @@ namespace Robust.Client.Graphics.Clyde
                     case Color color:
                         program.SetUniform(name, color);
                         break;
+                    case Color[] colorArr:
+                        program.SetUniform(name, colorArr);
+                        break;
                     case int i:
                         program.SetUniform(name, i);
                         break;

Robust.Client/Graphics/Clyde/Clyde.Shaders.cs

@@ -485,6 +485,13 @@ namespace Robust.Client.Graphics.Clyde
                 data.Parameters[name] = value;
             }
 
+            private protected override void SetParameterImpl(string name, Color[] value)
+            {
+                var data = Parent._shaderInstances[Handle];
+                data.ParametersDirty = true;
+                data.Parameters[name] = value;
+            }
+
             private protected override void SetParameterImpl(string name, int value)
             {
                 var data = Parent._shaderInstances[Handle];

Robust.Client/Graphics/Clyde/ClydeHeadless.cs

@@ -369,6 +369,10 @@ namespace Robust.Client.Graphics.Clyde
             {
             }
 
+            private protected override void SetParameterImpl(string name, Color[] value)
+            {
+            }
+
             private protected override void SetParameterImpl(string name, int value)
             {
             }

Robust.Client/Graphics/Clyde/GLObjects/Clyde.ShaderProgram.cs

@@ -334,7 +334,7 @@ namespace Robust.Client.Graphics.Clyde
             }
 
             [MethodImpl(MethodImplOptions.AggressiveInlining)]
-            private void SetUniformDirect(int slot, in Color color, bool convertToLinear=true)
+            private void SetUniformDirect(int slot, in Color color, bool convertToLinear = true)
             {
                 var converted = color;
                 if (convertToLinear)
@@ -349,6 +349,39 @@ namespace Robust.Client.Graphics.Clyde
                 }
             }
 
+            public void SetUniform(string uniformName, Color[] colors)
+            {
+                var uniformId = GetUniform(uniformName);
+                SetUniformDirect(uniformId, colors);
+            }
+
+            [MethodImpl(MethodImplOptions.AggressiveInlining)]
+            private void SetUniformDirect(int slot, Color[] colors, bool convertToLinear = true)
+            {
+                scoped Span<Color> colorsToPass;
+                if (convertToLinear)
+                {
+                    colorsToPass = stackalloc Color[colors.Length];
+                    for (int i = 0; i < colors.Length; i++)
+                    {
+                        colorsToPass[i] = Color.FromSrgb(colors[i]);
+                    }
+                }
+                else
+                {
+                    colorsToPass = colors;
+                }
+
+                unsafe
+                {
+                    fixed (Color* ptr = &colorsToPass[0])
+                    {
+                        GL.Uniform4(slot, colorsToPass.Length, (float*)ptr);
+                        _clyde.CheckGlError();
+                    }
+                }
+            }
+
             public void SetUniform(string uniformName, in Vector3 vector)
             {
                 var uniformId = GetUniform(uniformName);

Robust.Client/Graphics/Shaders/ParsedShader.cs

@@ -221,11 +221,12 @@ namespace Robust.Client.Graphics
 
         public static bool TypeSupportsArrays(this ShaderDataType type)
         {
-            // TODO: add support for int, and vec3/4 arrays
+            // TODO: add support for int, and vec3 arrays
             return
                 (type == ShaderDataType.Float) ||
                 (type == ShaderDataType.Vec2) ||
-                (type == ShaderDataType.Bool);
+                (type == ShaderDataType.Bool) ||
+                (type == ShaderDataType.Vec4);
         }
 
         [SuppressMessage("ReSharper", "StringLiteralTypo")]

Robust.Client/Graphics/Shaders/ShaderInstance.cs

@@ -113,6 +113,13 @@ namespace Robust.Client.Graphics
             SetParameterImpl(name, value);
         }
 
+        public void SetParameter(string name, Color[] value)
+        {
+            EnsureAlive();
+            EnsureMutable();
+            SetParameterImpl(name, value);
+        }
+
         public void SetParameter(string name, Vector4 value)
         {
             EnsureAlive();
@@ -223,6 +230,7 @@ namespace Robust.Client.Graphics
         private protected abstract void SetParameterImpl(string name, Vector3 value);
         private protected abstract void SetParameterImpl(string name, Vector4 value);
         private protected abstract void SetParameterImpl(string name, Color value);
+        private protected abstract void SetParameterImpl(string name, Color[] value);
         private protected abstract void SetParameterImpl(string name, int value);
         private protected abstract void SetParameterImpl(string name, Vector2i value);
         private protected abstract void SetParameterImpl(string name, bool value);

Robust.Client/Placement/PlacementMode.cs

@@ -144,7 +144,7 @@ namespace Robust.Client.Placement
             if (mousePos.MapId == MapId.Nullspace)
                 yield break;
 
-            var (_, (x, y)) = EntityCoordinates.FromMap(pManager.StartPoint.EntityId, mousePos, transformSys, pManager.EntityManager) - pManager.StartPoint;
+            var (_, (x, y)) = transformSys.ToCoordinates(pManager.StartPoint.EntityId, mousePos) - pManager.StartPoint;
             float iterations;
             Vector2 distance;
             if (Math.Abs(x) > Math.Abs(y))
@@ -176,7 +176,7 @@ namespace Robust.Client.Placement
             if (mousePos.MapId == MapId.Nullspace)
                 yield break;
 
-            var placementdiff = EntityCoordinates.FromMap(pManager.StartPoint.EntityId, mousePos, transformSys, pManager.EntityManager) - pManager.StartPoint;
+            var placementdiff = transformSys.ToCoordinates(pManager.StartPoint.EntityId, mousePos) - pManager.StartPoint;
 
             var xSign = Math.Sign(placementdiff.X);
             var ySign = Math.Sign(placementdiff.Y);
@@ -264,13 +264,15 @@ namespace Robust.Client.Placement
         protected EntityCoordinates ScreenToCursorGrid(ScreenCoordinates coords)
         {
             var mapCoords = pManager.EyeManager.PixelToMap(coords.Position);
+            var transformSys = pManager.EntityManager.System<SharedTransformSystem>();
+
             if (!pManager.MapManager.TryFindGridAt(mapCoords, out var gridUid, out var grid))
             {
-                return EntityCoordinates.FromMap(pManager.MapManager, mapCoords);
+
+                return transformSys.ToCoordinates(mapCoords);
             }
 
-            var transformSys = pManager.EntityManager.System<SharedTransformSystem>();
-            return EntityCoordinates.FromMap(gridUid, mapCoords, transformSys, pManager.EntityManager);
+            return transformSys.ToCoordinates(gridUid, mapCoords);
         }
     }
 }

Robust.Client/UserInterface/Controls/ScrollContainer.cs

@@ -28,6 +28,30 @@ namespace Robust.Client.UserInterface.Controls
         public int ScrollSpeedX { get; set; } = 50;
         public int ScrollSpeedY { get; set; } = 50;
 
+        public float VScroll
+        {
+            get => _vScrollBar.Value;
+            set => _vScrollBar.Value = value;
+        }
+
+        public float VScrollTarget
+        {
+            get => _vScrollBar.ValueTarget;
+            set => _vScrollBar.ValueTarget = value;
+        }
+
+        public float HScroll
+        {
+            get => _hScrollBar.Value;
+            set => _hScrollBar.Value = value;
+        }
+
+        public float HScrollTarget
+        {
+            get => _hScrollBar.ValueTarget;
+            set => _hScrollBar.ValueTarget = value;
+        }
+
         private bool _reserveScrollbarSpace;
         public bool ReserveScrollbarSpace
         {

Robust.Server/Audio/AudioSystem.cs

@@ -81,27 +81,27 @@ public sealed partial class AudioSystem : SharedAudioSystem
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? specifier, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
-        var entity = SetupAudio(filename, audioParams);
+        var entity = SetupAudio(specifier, audioParams);
         AddAudioFilter(entity, entity.Comp, playerFilter);
         entity.Comp.Global = true;
         return (entity, entity.Comp);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, Filter playerFilter, EntityUid uid, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? specifier, Filter playerFilter, EntityUid uid, bool recordReplay, AudioParams? audioParams = null)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (TerminatingOrDeleted(uid))
             return null;
 
-        var entity = SetupAudio(filename, audioParams);
+        var entity = SetupAudio(specifier, audioParams);
         // Move it after setting it up
         XformSystem.SetCoordinates(entity, new EntityCoordinates(uid, Vector2.Zero));
 
@@ -115,24 +115,24 @@ public sealed partial class AudioSystem : SharedAudioSystem
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(string? filename, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? specifier, EntityUid uid, AudioParams? audioParams = null)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (TerminatingOrDeleted(uid))
             return null;
 
-        var entity = SetupAudio(filename, audioParams);
+        var entity = SetupAudio(specifier, audioParams);
         XformSystem.SetCoordinates(entity, new EntityCoordinates(uid, Vector2.Zero));
 
         return (entity, entity.Comp);
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? specifier, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (TerminatingOrDeleted(coordinates.EntityId))
@@ -144,7 +144,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
         if (!coordinates.IsValid(EntityManager))
             return null;
 
-        var entity = SetupAudio(filename, audioParams);
+        var entity = SetupAudio(specifier, audioParams);
         XformSystem.SetCoordinates(entity, coordinates);
         AddAudioFilter(entity, entity.Comp, playerFilter);
 
@@ -152,10 +152,10 @@ public sealed partial class AudioSystem : SharedAudioSystem
     }
 
     /// <inheritdoc />
-    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(string? filename, EntityCoordinates coordinates,
+    public override (EntityUid Entity, AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? specifier, EntityCoordinates coordinates,
         AudioParams? audioParams = null)
     {
-        if (string.IsNullOrEmpty(filename))
+        if (specifier is null)
             return null;
 
         if (TerminatingOrDeleted(coordinates.EntityId))
@@ -168,7 +168,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
             return null;
 
         // TODO: Transform TryFindGridAt mess + optimisation required.
-        var entity = SetupAudio(filename, audioParams);
+        var entity = SetupAudio(specifier, audioParams);
         XformSystem.SetCoordinates(entity, coordinates);
 
         return (entity, entity.Comp);
@@ -191,7 +191,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
         if (sound == null)
             return null;
 
-        var audio = PlayPvs(GetSound(sound), source, audioParams ?? sound.Params);
+        var audio = PlayPvs(ResolveSound(sound), source, audioParams ?? sound.Params);
 
         if (audio == null)
             return null;
@@ -206,7 +206,7 @@ public sealed partial class AudioSystem : SharedAudioSystem
         if (sound == null)
             return null;
 
-        var audio = PlayPvs(GetSound(sound), coordinates, audioParams ?? sound.Params);
+        var audio = PlayPvs(ResolveSound(sound), coordinates, audioParams ?? sound.Params);
 
         if (audio == null)
             return null;
@@ -215,12 +215,12 @@ public sealed partial class AudioSystem : SharedAudioSystem
         return audio;
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, ICommonSession recipient, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? filename, ICommonSession recipient, AudioParams? audioParams = null)
     {
         return PlayGlobal(filename, Filter.SinglePlayer(recipient), false, audioParams);
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(string? filename, EntityUid recipient, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? filename, EntityUid recipient, AudioParams? audioParams = null)
     {
         if (TryComp(recipient, out ActorComponent? actor))
             return PlayGlobal(filename, actor.PlayerSession, audioParams);
@@ -228,12 +228,12 @@ public sealed partial class AudioSystem : SharedAudioSystem
         return null;
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? filename, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null)
     {
         return PlayEntity(filename, Filter.SinglePlayer(recipient), uid, false, audioParams);
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(string? filename, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? filename, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null)
     {
         if (TryComp(recipient, out ActorComponent? actor))
             return PlayEntity(filename, actor.PlayerSession, uid, audioParams);
@@ -241,12 +241,12 @@ public sealed partial class AudioSystem : SharedAudioSystem
         return null;
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? filename, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
         return PlayStatic(filename, Filter.SinglePlayer(recipient), coordinates, false, audioParams);
     }
 
-    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(string? filename, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
+    public override (EntityUid Entity, AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? filename, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
         if (TryComp(recipient, out ActorComponent? actor))
             return PlayStatic(filename, actor.PlayerSession, coordinates, audioParams);

Robust.Server/BaseServer.cs

@@ -297,7 +297,7 @@ namespace Robust.Server
                 : null;
 
             // Set up the VFS
-            _resources.Initialize(dataDir);
+            _resources.Initialize(dataDir, hideUserDataDir: false);
 
             var mountOptions = _commandLineArgs != null
                 ? MountOptions.Merge(_commandLineArgs.MountOptions, Options.MountOptions) : Options.MountOptions;

Robust.Server/GameObjects/EntitySystems/VisibilitySystem.cs

@@ -6,7 +6,7 @@ using Robust.Shared.ViewVariables;
 
 namespace Robust.Server.GameObjects
 {
-    public sealed class VisibilitySystem : EntitySystem
+    public sealed class VisibilitySystem : SharedVisibilitySystem
     {
         [Dependency] private readonly PvsSystem _pvs = default!;
         [Dependency] private readonly IViewVariablesManager _vvManager = default!;
@@ -40,7 +40,7 @@ namespace Robust.Server.GameObjects
             EntityManager.EntityInitialized -= OnEntityInit;
         }
 
-        public void AddLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+        public override void AddLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
         {
             ent.Comp ??= _visibilityQuery.CompOrNull(ent.Owner) ?? AddComp<VisibilityComponent>(ent.Owner);
 
@@ -53,7 +53,7 @@ namespace Robust.Server.GameObjects
                 RefreshVisibility(ent);
         }
 
-        public void RemoveLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+        public override void RemoveLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
         {
             if (!_visibilityQuery.Resolve(ent.Owner, ref ent.Comp, false))
                 return;
@@ -67,7 +67,7 @@ namespace Robust.Server.GameObjects
                 RefreshVisibility(ent);
         }
 
-        public void SetLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+        public override void SetLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
         {
             ent.Comp ??= _visibilityQuery.CompOrNull(ent.Owner) ?? AddComp<VisibilityComponent>(ent.Owner);
 
@@ -90,14 +90,14 @@ namespace Robust.Server.GameObjects
             RefreshVisibility(ent.Owner, null, ent.Comp);
         }
 
-        public void RefreshVisibility(EntityUid uid,
+        public override void RefreshVisibility(EntityUid uid,
             VisibilityComponent? visibilityComponent = null,
             MetaDataComponent? meta = null)
         {
             RefreshVisibility((uid, visibilityComponent, meta));
         }
 
-        public void RefreshVisibility(Entity<VisibilityComponent?, MetaDataComponent?> ent)
+        public override void RefreshVisibility(Entity<VisibilityComponent?, MetaDataComponent?> ent)
         {
             if (!_metaQuery.Resolve(ent, ref ent.Comp2, false))
                 return;

Robust.Shared.Maths/Properties/AssemblyInfo.cs

@@ -6,4 +6,3 @@
 
 [assembly: InternalsVisibleTo("Robust.Client")]
 [assembly: InternalsVisibleTo("Robust.UnitTesting")]
-[assembly: InternalsVisibleTo("Content.Benchmarks")]

Robust.Shared/Audio/ResolvedSoundSpecifier.cs

@@ -0,0 +1,90 @@
+using System;
+using JetBrains.Annotations;
+using Robust.Shared.Utility;
+using Robust.Shared.Serialization;
+using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.Shared.Prototypes;
+
+namespace Robust.Shared.Audio;
+
+/// <summary>
+/// Represents a path to a sound resource, either as a literal path or as a collection ID and index.
+/// </summary>
+/// <seealso cref="ResolvedPathSpecifier"/>
+/// <seealso cref="ResolvedCollectionSpecifier"/>
+[Serializable, NetSerializable]
+public abstract partial class ResolvedSoundSpecifier {
+    [Obsolete("String literals for sounds are deprecated, use a SoundSpecifier or ResolvedSoundSpecifier as appropriate instead")]
+    public static implicit operator ResolvedSoundSpecifier(string s) => new ResolvedPathSpecifier(s);
+    [Obsolete("String literals for sounds are deprecated, use a SoundSpecifier or ResolvedSoundSpecifier as appropriate instead")]
+    public static implicit operator ResolvedSoundSpecifier(ResPath s) => new ResolvedPathSpecifier(s);
+
+    /// <summary>
+    /// Returns whether <c>s</c> is null, or if it contains an empty path/collection ID.
+    /// </summary>
+    public static bool IsNullOrEmpty(ResolvedSoundSpecifier? s) {
+        return s switch {
+            null => true,
+            ResolvedPathSpecifier path => path.Path.ToString() == "",
+            ResolvedCollectionSpecifier collection => string.IsNullOrEmpty(collection.Collection),
+            _ => throw new ArgumentOutOfRangeException("s", s, "argument is not a ResolvedPathSpecifier or a ResolvedCollectionSpecifier"),
+        };
+    }
+}
+
+/// <summary>
+/// Represents a path to a sound resource as a literal path.
+/// </summary>
+/// <seealso cref="ResolvedCollectionSpecifier"/>
+[Serializable, NetSerializable]
+public sealed partial class ResolvedPathSpecifier : ResolvedSoundSpecifier {
+    /// <summary>
+    /// The resource path of the sound.
+    /// </summary>
+    public ResPath Path { get; private set; }
+
+    override public string ToString() =>
+        $"ResolvedPathSpecifier({Path})";
+
+    [UsedImplicitly]
+    private ResolvedPathSpecifier()
+    {
+    }
+    public ResolvedPathSpecifier(ResPath path)
+    {
+        Path = path;
+    }
+    public ResolvedPathSpecifier(string path) : this(new ResPath(path))
+    {
+    }
+}
+
+/// <summary>
+/// Represents a path to a sound resource as a collection ID and index.
+/// </summary>
+/// <seealso cref="ResolvedPathSpecifier"/>
+[Serializable, NetSerializable]
+public sealed partial class ResolvedCollectionSpecifier : ResolvedSoundSpecifier {
+    /// <summary>
+    /// The ID of the <see cref="SoundCollectionPrototype">sound collection</see> to look up.
+    /// </summary>
+    public ProtoId<SoundCollectionPrototype>? Collection { get; private set; }
+    /// <summary>
+    /// The index of the file in the associated sound collection to play.
+    /// </summary>
+    public int Index { get; private set; }
+
+    override public string ToString() =>
+        $"ResolvedCollectionSpecifier({Collection}, {Index})";
+
+    [UsedImplicitly]
+    private ResolvedCollectionSpecifier()
+    {
+    }
+
+    public ResolvedCollectionSpecifier(string collection, int index)
+    {
+        Collection = collection;
+        Index = index;
+    }
+}

Robust.Shared/Audio/SoundSpecifier.cs

@@ -27,6 +27,9 @@ public sealed partial class SoundPathSpecifier : SoundSpecifier
     [DataField(Node, customTypeSerializer: typeof(ResPathSerializer), required: true)]
     public ResPath Path { get; private set; }
 
+    override public string ToString() =>
+        $"SoundPathSpecifier({Path})";
+
     [UsedImplicitly]
     private SoundPathSpecifier()
     {
@@ -52,6 +55,9 @@ public sealed partial class SoundCollectionSpecifier : SoundSpecifier
     [DataField(Node, customTypeSerializer: typeof(PrototypeIdSerializer<SoundCollectionPrototype>), required: true)]
     public string? Collection { get; private set; }
 
+    override public string ToString() =>
+        $"SoundCollectionSpecifier({Collection})";
+
     [UsedImplicitly]
     public SoundCollectionSpecifier() { }
 

Robust.Shared/Audio/Systems/SharedAudioSystem.cs

@@ -283,33 +283,60 @@ public abstract partial class SharedAudioSystem : EntitySystem
     }
 
     /// <summary>
-    /// Resolves the filepath to a sound file.
+    /// Resolve a sound specifier so it can be consistently played back on all clients.
     /// </summary>
-    public string GetSound(SoundSpecifier specifier)
+    public ResolvedSoundSpecifier ResolveSound(SoundSpecifier specifier)
     {
         switch (specifier)
         {
             case SoundPathSpecifier path:
-                return path.Path == default ? string.Empty : path.Path.ToString();
+                return new ResolvedPathSpecifier(path.Path == default ? string.Empty : path.Path.ToString());
 
             case SoundCollectionSpecifier collection:
             {
                 if (collection.Collection == null)
-                    return string.Empty;
+                    return new ResolvedPathSpecifier(string.Empty);
 
                 var soundCollection = ProtoMan.Index<SoundCollectionPrototype>(collection.Collection);
-                return RandMan.Pick(soundCollection.PickFiles).ToString();
+                var index = RandMan.Next(soundCollection.PickFiles.Count);
+                return new ResolvedCollectionSpecifier(collection.Collection, index);
             }
         }
 
-        return string.Empty;
+        return new ResolvedPathSpecifier(string.Empty);
+    }
+
+    /// <summary>
+    /// Resolves the filepath to a sound file.
+    /// </summary>
+    [Obsolete("Use ResolveSound() and pass around resolved sound specifiers instead.")]
+    public string GetSound(SoundSpecifier specifier)
+    {
+        var resolved = ResolveSound(specifier);
+        return GetAudioPath(resolved);
     }
 
     #region AudioParams
 
-    protected Entity<AudioComponent> SetupAudio(string? fileName, AudioParams? audioParams, bool initialize = true, TimeSpan? length = null)
+    [return: NotNullIfNotNull(nameof(specifier))]
+    public string? GetAudioPath(ResolvedSoundSpecifier? specifier)
+    {
+        return specifier switch {
+            ResolvedPathSpecifier path =>
+                path.Path.ToString(),
+            ResolvedCollectionSpecifier collection =>
+                collection.Collection is null ?
+                    string.Empty :
+                    ProtoMan.Index<SoundCollectionPrototype>(collection.Collection).PickFiles[collection.Index].ToString(),
+            null => null,
+            _ => throw new ArgumentOutOfRangeException("specifier", specifier, "argument is not a ResolvedPathSpecifier or a ResolvedCollectionSpecifier"),
+        };
+    }
+
+    protected Entity<AudioComponent> SetupAudio(ResolvedSoundSpecifier? specifier, AudioParams? audioParams, bool initialize = true, TimeSpan? length = null)
     {
         var uid = EntityManager.CreateEntityUninitialized("Audio", MapCoordinates.Nullspace);
+        var fileName = GetAudioPath(specifier);
         DebugTools.Assert(!string.IsNullOrEmpty(fileName) || length is not null);
         MetadataSys.SetEntityName(uid, $"Audio ({fileName})", raiseEvents: false);
         audioParams ??= AudioParams.Default;
@@ -395,8 +422,9 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <summary>
     /// Gets the timespan of the specified audio.
     /// </summary>
-    public TimeSpan GetAudioLength(string filename)
+    public TimeSpan GetAudioLength(ResolvedSoundSpecifier specifier)
     {
+        var filename = GetAudioPath(specifier) ?? string.Empty;
         if (!filename.StartsWith("/"))
             throw new ArgumentException("Path must be rooted");
 
@@ -429,7 +457,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="playerFilter">The set of players that will hear the sound.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(string? filename, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? filename, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file globally, without position.
@@ -438,7 +466,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="playerFilter">The set of players that will hear the sound.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(SoundSpecifier? sound, Filter playerFilter, bool recordReplay, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayGlobal(GetSound(sound), playerFilter, recordReplay, audioParams ?? sound.Params);
+        return sound == null ? null : PlayGlobal(ResolveSound(sound), playerFilter, recordReplay, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -446,7 +474,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(string? filename, ICommonSession recipient, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? filename, ICommonSession recipient, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file globally, without position.
@@ -455,7 +483,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="recipient">The player that will hear the sound.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(SoundSpecifier? sound, ICommonSession recipient, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayGlobal(GetSound(sound), recipient, audioParams ?? sound.Params);
+        return sound == null ? null : PlayGlobal(ResolveSound(sound), recipient, audioParams ?? sound.Params);
     }
 
     public abstract void LoadStream<T>(Entity<AudioComponent> entity, T stream);
@@ -465,7 +493,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(string? filename, EntityUid recipient, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(ResolvedSoundSpecifier? filename, EntityUid recipient, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file globally, without position.
@@ -474,7 +502,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="recipient">The player that will hear the sound.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayGlobal(SoundSpecifier? sound, EntityUid recipient, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayGlobal(GetSound(sound), recipient, audioParams ?? sound.Params);
+        return sound == null ? null : PlayGlobal(ResolveSound(sound), recipient, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -483,7 +511,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="playerFilter">The set of players that will hear the sound.</param>
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(string? filename, Filter playerFilter, EntityUid uid, bool recordReplay, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? filename, Filter playerFilter, EntityUid uid, bool recordReplay, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file following an entity.
@@ -491,7 +519,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(string? filename, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? filename, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file following an entity.
@@ -499,7 +527,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(string? filename, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(ResolvedSoundSpecifier? filename, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file following an entity.
@@ -509,7 +537,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(SoundSpecifier? sound, Filter playerFilter, EntityUid uid, bool recordReplay, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayEntity(GetSound(sound), playerFilter, uid, recordReplay, audioParams ?? sound.Params);
+        return sound == null ? null : PlayEntity(ResolveSound(sound), playerFilter, uid, recordReplay, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -520,7 +548,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(SoundSpecifier? sound, ICommonSession recipient, EntityUid uid, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayEntity(GetSound(sound), recipient, uid, audioParams ?? sound.Params);
+        return sound == null ? null : PlayEntity(ResolveSound(sound), recipient, uid, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -531,7 +559,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayEntity(SoundSpecifier? sound, EntityUid recipient, EntityUid uid, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayEntity(GetSound(sound), recipient, uid, audioParams ?? sound.Params);
+        return sound == null ? null : PlayEntity(ResolveSound(sound), recipient, uid, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -541,7 +569,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(SoundSpecifier? sound, EntityUid uid, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayPvs(GetSound(sound), uid, audioParams ?? sound.Params);
+        return sound == null ? null : PlayPvs(ResolveSound(sound), uid, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -551,7 +579,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="coordinates">The EntityCoordinates to attach the audio source to.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(SoundSpecifier? sound, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayPvs(GetSound(sound), coordinates, audioParams ?? sound.Params);
+        return sound == null ? null : PlayPvs(ResolveSound(sound), coordinates, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -559,7 +587,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// </summary>
     /// <param name="sound">The sound specifier that points the audio file(s) that should be played.</param>
     /// <param name="coordinates">The EntityCoordinates to attach the audio source to.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(string? filename,
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? filename,
         EntityCoordinates coordinates, AudioParams? audioParams = null);
 
     /// <summary>
@@ -567,7 +595,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// </summary>
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="uid">The UID of the entity "emitting" the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(string? filename, EntityUid uid,
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayPvs(ResolvedSoundSpecifier? filename, EntityUid uid,
         AudioParams? audioParams = null);
 
     /// <summary>
@@ -604,7 +632,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="playerFilter">The set of players that will hear the sound.</param>
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(string? filename, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? filename, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file at a static position.
@@ -612,7 +640,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(string? filename, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? filename, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file at a static position.
@@ -620,7 +648,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="filename">The resource path to the OGG Vorbis file to play.</param>
     /// <param name="recipient">The player that will hear the sound.</param>
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
-    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(string? filename, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null);
+    public abstract (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(ResolvedSoundSpecifier? filename, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null);
 
     /// <summary>
     /// Play an audio file at a static position.
@@ -630,7 +658,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(SoundSpecifier? sound, Filter playerFilter, EntityCoordinates coordinates, bool recordReplay, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayStatic(GetSound(sound), playerFilter, coordinates, recordReplay, audioParams);
+        return sound == null ? null : PlayStatic(ResolveSound(sound), playerFilter, coordinates, recordReplay, audioParams);
     }
 
     /// <summary>
@@ -641,7 +669,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(SoundSpecifier? sound, ICommonSession recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayStatic(GetSound(sound), recipient, coordinates, audioParams ?? sound.Params);
+        return sound == null ? null : PlayStatic(ResolveSound(sound), recipient, coordinates, audioParams ?? sound.Params);
     }
 
     /// <summary>
@@ -652,7 +680,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     /// <param name="coordinates">The coordinates at which to play the audio.</param>
     public (EntityUid Entity, Components.AudioComponent Component)? PlayStatic(SoundSpecifier? sound, EntityUid recipient, EntityCoordinates coordinates, AudioParams? audioParams = null)
     {
-        return sound == null ? null : PlayStatic(GetSound(sound), recipient, coordinates, audioParams ?? sound.Params);
+        return sound == null ? null : PlayStatic(ResolveSound(sound), recipient, coordinates, audioParams ?? sound.Params);
     }
 
     // These are just here for replays now.
@@ -665,7 +693,7 @@ public abstract partial class SharedAudioSystem : EntitySystem
     [NetSerializable, Serializable]
     protected abstract class AudioMessage : EntityEventArgs
     {
-        public string FileName = string.Empty;
+        public ResolvedSoundSpecifier Specifier = new ResolvedPathSpecifier(string.Empty);
         public AudioParams AudioParams;
     }
 

Robust.Shared/ContentPack/AssemblyTypeChecker.Config.cs

@@ -88,6 +88,7 @@ namespace Robust.Shared.ContentPack
             public string SystemAssemblyName = default!;
             public HashSet<VerifierError> AllowedVerifierErrors = default!;
             public List<string> WhitelistedNamespaces = default!;
+            public List<string> AllowedAssemblyPrefixes = default!;
             public Dictionary<string, Dictionary<string, TypeConfig>> Types = default!;
         }
 

Robust.Shared/ContentPack/AssemblyTypeChecker.cs

@@ -131,6 +131,16 @@ namespace Robust.Shared.ContentPack
                 return false;
             }
 
+#pragma warning disable RA0004
+            var loadedConfig = _config.Result;
+#pragma warning restore RA0004
+
+            if (!loadedConfig.AllowedAssemblyPrefixes.Any(allowedNamePrefix => asmName.StartsWith(allowedNamePrefix)))
+            {
+                _sawmill.Error($"Assembly name '{asmName}' is not allowed for a content assembly");
+                return false;
+            }
+
             if (VerifyIL)
             {
                 if (!DoVerifyIL(asmName, resolver, peReader, reader))
@@ -179,10 +189,6 @@ namespace Robust.Shared.ContentPack
                 return true;
             }
 
-#pragma warning disable RA0004
-            var loadedConfig = _config.Result;
-#pragma warning restore RA0004
-
             var badRefs = new ConcurrentBag<EntityHandle>();
 
             // We still do explicit type reference scanning, even though the actual whitelists work with raw members.

Robust.Shared/ContentPack/DirLoader.cs

@@ -60,7 +60,7 @@ namespace Robust.Shared.ContentPack
 
             internal string GetPath(ResPath relPath)
             {
-                return Path.GetFullPath(Path.Combine(_directory.FullName, relPath.ToRelativeSystemPath()));
+                return PathHelpers.SafeGetResourcePath(_directory.FullName, relPath);
             }
 
             /// <inheritdoc />

Robust.Shared/ContentPack/IResourceManagerInternal.cs

@@ -14,7 +14,11 @@ namespace Robust.Shared.ContentPack
         /// The directory to use for user data.
         /// If null, a virtual temporary file system is used instead.
         /// </param>
-        void Initialize(string? userData);
+        /// <param name="hideUserDataDir">
+        /// If true, <see cref="IWritableDirProvider.RootDir"/> will be hidden on
+        /// <see cref="IResourceManager.UserData"/>.
+        /// </param>
+        void Initialize(string? userData, bool hideUserDataDir);
 
         /// <summary>
         ///     Mounts a single stream as a content file. Useful for unit testing.

Robust.Shared/ContentPack/IWritableDirProvider.cs

@@ -13,7 +13,7 @@ namespace Robust.Shared.ContentPack
     {
         /// <summary>
         /// The root path of this provider.
-        /// Can be null if it's a virtual provider.
+        /// Can be null if it's a virtual provider or the path is protected (e.g. on the client).
         /// </summary>
         string? RootDir { get; }
 

Robust.Shared/ContentPack/ModLoader.cs

@@ -93,19 +93,23 @@ namespace Robust.Shared.ContentPack
         {
             var sw = Stopwatch.StartNew();
             Sawmill.Debug("LOADING modules");
-            var files = new Dictionary<string, (ResPath Path, string[] references)>();
+            var files = new Dictionary<string, (ResPath Path, MemoryStream data, string[] references)>();
 
             // Find all modules we want to load.
             foreach (var fullPath in paths)
             {
                 using var asmFile = _res.ContentFileRead(fullPath);
-                var refData = GetAssemblyReferenceData(asmFile);
+                var ms = new MemoryStream();
+                asmFile.CopyTo(ms);
+
+                ms.Position = 0;
+                var refData = GetAssemblyReferenceData(ms);
                 if (refData == null)
                     continue;
 
                 var (asmRefs, asmName) = refData.Value;
 
-                if (!files.TryAdd(asmName, (fullPath, asmRefs)))
+                if (!files.TryAdd(asmName, (fullPath, ms, asmRefs)))
                 {
                     Sawmill.Error("Found multiple modules with the same assembly name " +
                                   $"'{asmName}', A: {files[asmName].Path}, B: {fullPath}.");
@@ -122,10 +126,10 @@ namespace Robust.Shared.ContentPack
 
                 Parallel.ForEach(files, pair =>
                 {
-                    var (name, (path, _)) = pair;
+                    var (name, (_, data, _)) = pair;
 
-                    using var stream = _res.ContentFileRead(path);
-                    if (!typeChecker.CheckAssembly(stream, resolver))
+                    data.Position = 0;
+                    if (!typeChecker.CheckAssembly(data, resolver))
                     {
                         throw new TypeCheckFailedException($"Assembly {name} failed type checks.");
                     }
@@ -137,14 +141,15 @@ namespace Robust.Shared.ContentPack
             var nodes = TopologicalSort.FromBeforeAfter(
                 files,
                 kv => kv.Key,
-                kv => kv.Value.Path,
+                kv => kv.Value,
                 _ => Array.Empty<string>(),
                 kv => kv.Value.references,
                 allowMissing: true); // missing refs would be non-content assemblies so allow that.
 
             // Actually load them in the order they depend on each other.
-            foreach (var path in TopologicalSort.Sort(nodes))
+            foreach (var item in TopologicalSort.Sort(nodes))
             {
+                var (path, memory, _) = item;
                 Sawmill.Debug($"Loading module: '{path}'");
                 try
                 {
@@ -156,9 +161,9 @@ namespace Robust.Shared.ContentPack
                     }
                     else
                     {
-                        using var assemblyStream = _res.ContentFileRead(path);
+                        memory.Position = 0;
                         using var symbolsStream = _res.ContentFileReadOrNull(path.WithExtension("pdb"));
-                        LoadGameAssembly(assemblyStream, symbolsStream, skipVerify: true);
+                        LoadGameAssembly(memory, symbolsStream, skipVerify: true);
                     }
                 }
                 catch (Exception e)
@@ -174,7 +179,7 @@ namespace Robust.Shared.ContentPack
 
         private (string[] refs, string name)? GetAssemblyReferenceData(Stream stream)
         {
-            using var reader = ModLoader.MakePEReader(stream);
+            using var reader = ModLoader.MakePEReader(stream, leaveOpen: true);
             var metaReader = reader.GetMetadataReader();
 
             var name = metaReader.GetString(metaReader.GetAssemblyDefinition().Name);

Robust.Shared/ContentPack/PathHelpers.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.IO;
 using System.Runtime.InteropServices;
+using Robust.Shared.Utility;
 
 namespace Robust.Shared.ContentPack
 {
@@ -63,5 +64,27 @@ namespace Robust.Shared.ContentPack
             !OperatingSystem.IsWindows()
             && !OperatingSystem.IsMacOS();
 
+
+        internal static string SafeGetResourcePath(string baseDir, ResPath path)
+        {
+            var relSysPath = path.ToRelativeSystemPath();
+            if (relSysPath.Contains("\\..") || relSysPath.Contains("/.."))
+            {
+                // Hard cap on any exploit smuggling a .. in there.
+                // Since that could allow leaving sandbox.
+                throw new InvalidOperationException($"This branch should never be reached. Path: {path}");
+            }
+
+            var retPath = Path.GetFullPath(Path.Join(baseDir, relSysPath));
+            // better safe than sorry check
+            if (!retPath.StartsWith(baseDir))
+            {
+                // Allow path to match if it's just missing the directory separator at the end.
+                if (retPath != baseDir.TrimEnd(Path.DirectorySeparatorChar))
+                    throw new InvalidOperationException($"This branch should never be reached. Path: {path}");
+            }
+
+            return retPath;
+        }
     }
 }

Robust.Shared/ContentPack/ResourceManager.cs

@@ -41,13 +41,13 @@ namespace Robust.Shared.ContentPack
         public IWritableDirProvider UserData { get; private set; } = default!;
 
         /// <inheritdoc />
-        public virtual void Initialize(string? userData)
+        public virtual void Initialize(string? userData, bool hideRootDir)
         {
             Sawmill = _logManager.GetSawmill("res");
 
             if (userData != null)
             {
-                UserData = new WritableDirProvider(Directory.CreateDirectory(userData));
+                UserData = new WritableDirProvider(Directory.CreateDirectory(userData), hideRootDir);
             }
             else
             {
@@ -379,7 +379,13 @@ namespace Robust.Shared.ContentPack
             {
                 if (root is DirLoader loader)
                 {
-                    yield return new ResPath(loader.GetPath(new ResPath(@"/")));
+                    var rootDir = loader.GetPath(new ResPath(@"/"));
+
+                    // TODO: GET RID OF THIS.
+                    // This code shouldn't be passing OS disk paths through ResPath.
+                    rootDir = rootDir.Replace(Path.DirectorySeparatorChar, '/');
+
+                    yield return new ResPath(rootDir);
                 }
             }
         }

Robust.Shared/ContentPack/Sandbox.yml

@@ -17,6 +17,10 @@ WhitelistedNamespaces:
 - Content
 - OpenDreamShared
 
+AllowedAssemblyPrefixes:
+- OpenDream
+- Content
+
 # The type whitelist does NOT care about which assembly types come from.
 # This is because types switch assembly all the time.
 # Just look up stuff like StreamReader on https://apisof.net.
@@ -696,7 +700,7 @@ Types:
       - "bool IsMatch(string, string, System.Text.RegularExpressions.RegexOptions, System.TimeSpan)"
       - "int GroupNumberFromName(string)"
       - "int[] GetGroupNumbers()"
-      - "string Escape()"
+      - "string Escape(string)"
       - "string GroupNameFromNumber(int)"
       - "string Replace(string, string)"
       - "string Replace(string, string, int)"

Robust.Shared/ContentPack/WritableDirProvider.cs

@@ -10,17 +10,22 @@ namespace Robust.Shared.ContentPack
     /// <inheritdoc />
     internal sealed class WritableDirProvider : IWritableDirProvider
     {
-        /// <inheritdoc />
+        private readonly bool _hideRootDir;
+
         public string RootDir { get; }
 
+        string? IWritableDirProvider.RootDir => _hideRootDir ? null : RootDir;
+
         /// <summary>
         /// Constructs an instance of <see cref="WritableDirProvider"/>.
         /// </summary>
         /// <param name="rootDir">Root file system directory to allow writing.</param>
-        public WritableDirProvider(DirectoryInfo rootDir)
+        /// <param name="hideRootDir">If true, <see cref="IWritableDirProvider.RootDir"/> is reported as null.</param>
+        public WritableDirProvider(DirectoryInfo rootDir, bool hideRootDir)
         {
             // FullName does not have a trailing separator, and we MUST have a separator.
             RootDir = rootDir.FullName + Path.DirectorySeparatorChar.ToString();
+            _hideRootDir = hideRootDir;
         }
 
         #region File Access
@@ -119,7 +124,7 @@ namespace Robust.Shared.ContentPack
                 throw new FileNotFoundException();
 
             var dirInfo = new DirectoryInfo(GetFullPath(path));
-            return new WritableDirProvider(dirInfo);
+            return new WritableDirProvider(dirInfo, _hideRootDir);
         }
 
         /// <inheritdoc />
@@ -180,20 +185,7 @@ namespace Robust.Shared.ContentPack
 
             path = path.Clean();
 
-            return GetFullPath(RootDir, path);
-        }
-
-        private static string GetFullPath(string root, ResPath path)
-        {
-            var relPath = path.ToRelativeSystemPath();
-            if (relPath.Contains("\\..") || relPath.Contains("/.."))
-            {
-                // Hard cap on any exploit smuggling a .. in there.
-                // Since that could allow leaving sandbox.
-                throw new InvalidOperationException($"This branch should never be reached. Path: {path}");
-            }
-
-            return Path.GetFullPath(Path.Combine(root, relPath));
+            return PathHelpers.SafeGetResourcePath(RootDir, path);
         }
     }
 }

Robust.Shared/EntitySerialization/EntitySerializer.cs

@@ -271,7 +271,10 @@ public sealed class EntitySerializer : ISerializationContext,
         foreach (var (origId, prototypeId) in savedMap)
         {
             if (_tileDef.TryGetDefinition(prototypeId, out var definition))
+            {
                 _tileMap.TryAdd(definition.TileId, origId);
+                _yamlTileIds.Add(origId); // Make sure we record the IDs we're using so when we need to reserve new ones we can
+            }
         }
     }
 
@@ -593,7 +596,7 @@ public sealed class EntitySerializer : ISerializationContext,
     public MappingDataNode Write()
     {
         DebugTools.AssertEqual(Maps.ToHashSet().Count, Maps.Count, "Duplicate maps?");
-        DebugTools.AssertEqual(Grids.ToHashSet().Count, Grids.Count, "Duplicate frids?");
+        DebugTools.AssertEqual(Grids.ToHashSet().Count, Grids.Count, "Duplicate grids?");
         DebugTools.AssertEqual(Orphans.ToHashSet().Count, Orphans.Count, "Duplicate orphans?");
         DebugTools.AssertEqual(Nullspace.ToHashSet().Count, Nullspace.Count, "Duplicate nullspace?");
 

Robust.Shared/GameObjects/Components/Eye/VisibilityComponent.cs

@@ -1,14 +1,13 @@
-using Robust.Shared.GameObjects;
 using Robust.Shared.Serialization.Manager.Attributes;
 
-namespace Robust.Server.GameObjects
+namespace Robust.Shared.GameObjects
 {
     /// <summary>
     /// Controls PVS visibility of entities. THIS COMPONENT CONTROLS WHETHER ENTITIES ARE NETWORKED TO PLAYERS
     /// AND SHOULD NOT BE USED AS THE SOLE WAY TO HIDE AN ENTITY FROM A PLAYER.
     /// </summary>
     [RegisterComponent]
-    [Access(typeof(VisibilitySystem))]
+    [Access(typeof(SharedVisibilitySystem))]
     public sealed partial class VisibilityComponent : Component
     {
         /// <summary>

Robust.Shared/GameObjects/EntityManager.Components.cs

@@ -1075,6 +1075,97 @@ namespace Robust.Shared.GameObjects
             return TryGetComponent(uid.Value, netId, out component, meta);
         }
 
+        /// <inheritdoc/>
+        public bool TryCopyComponent<T>(EntityUid source, EntityUid target, ref T? sourceComponent, [NotNullWhen(true)] out T? targetComp, MetaDataComponent? meta = null) where T : IComponent
+        {
+            if (!MetaQuery.Resolve(target, ref meta))
+            {
+                targetComp = default;
+                return false;
+            }
+
+            if (sourceComponent == null && !TryGetComponent(source, out sourceComponent))
+            {
+                targetComp = default;
+                return false;
+            }
+
+            targetComp = CopyComponentInternal(source, target, sourceComponent, meta);
+            return true;
+        }
+
+        /// <inheritdoc/>
+        public bool TryCopyComponents(
+            EntityUid source,
+            EntityUid target,
+            MetaDataComponent? meta = null,
+            params Type[] sourceComponents)
+        {
+            if (!MetaQuery.TryGetComponent(source, out meta))
+                return false;
+
+            var allCopied = true;
+
+            foreach (var type in sourceComponents)
+            {
+                if (!TryGetComponent(source, type, out var srcComp))
+                {
+                    allCopied = false;
+                    continue;
+                }
+
+                CopyComponent(source, target, srcComp, meta: meta);
+            }
+
+            return allCopied;
+        }
+
+        /// <inheritdoc/>
+        public IComponent CopyComponent(EntityUid source, EntityUid target, IComponent sourceComponent, MetaDataComponent? meta = null)
+        {
+            if (!MetaQuery.Resolve(target, ref meta))
+            {
+                throw new InvalidOperationException();
+            }
+
+            return CopyComponentInternal(source, target, sourceComponent, meta);
+        }
+
+        /// <inheritdoc/>
+        public T CopyComponent<T>(EntityUid source, EntityUid target, T sourceComponent,MetaDataComponent? meta = null) where T : IComponent
+        {
+            if (!MetaQuery.Resolve(target, ref meta))
+            {
+                throw new InvalidOperationException();
+            }
+
+            return CopyComponentInternal(source, target, sourceComponent, meta);
+        }
+
+        /// <inheritdoc/>
+        public void CopyComponents(EntityUid source, EntityUid target, MetaDataComponent? meta = null, params IComponent[] sourceComponents)
+        {
+            if (!MetaQuery.Resolve(target, ref meta))
+                return;
+
+            foreach (var comp in sourceComponents)
+            {
+                CopyComponentInternal(source, target, comp, meta);
+            }
+        }
+
+        private T CopyComponentInternal<T>(EntityUid source, EntityUid target, T sourceComponent, MetaDataComponent meta) where T : IComponent
+        {
+            var compReg = ComponentFactory.GetRegistration(sourceComponent.GetType());
+            var component = (T)ComponentFactory.GetComponent(compReg);
+
+            _serManager.CopyTo(sourceComponent, ref component, notNullableOverride: true);
+            component.Owner = target;
+
+            AddComponentInternal(target, component, compReg, true, false, meta);
+            return component;
+        }
+
         public EntityQuery<TComp1> GetEntityQuery<TComp1>() where TComp1 : IComponent
         {
             var comps = _entTraitArray[CompIdx.ArrayIndex<TComp1>()];

Robust.Shared/GameObjects/EntitySystem.Proxy.cs

@@ -175,7 +175,7 @@ public partial class EntitySystem
     protected void DirtyFields<T>(EntityUid uid, T comp, MetaDataComponent? meta, params ReadOnlySpan<string> fields)
         where T : IComponentDelta
     {
-        EntityManager.DirtyFields(uid, comp, meta);
+        EntityManager.DirtyFields(uid, comp, meta, fields);
     }
 
     /// <summary>
@@ -565,6 +565,52 @@ public partial class EntitySystem
 
     #endregion
 
+    #region Component Copy
+
+    /// <inheritdoc cref="IEntityManager.TryCopyComponent"/>
+    protected bool TryCopyComponent<T>(
+        EntityUid source,
+        EntityUid target,
+        ref T? sourceComponent,
+        [NotNullWhen(true)] out T? targetComp,
+        MetaDataComponent? meta = null) where T : IComponent
+    {
+        return EntityManager.TryCopyComponent(source, target, ref sourceComponent, out targetComp, meta);
+    }
+
+    /// <inheritdoc cref="IEntityManager.TryCopyComponents"/>
+    protected bool TryCopyComponents(
+        EntityUid source,
+        EntityUid target,
+        MetaDataComponent? meta = null,
+        params Type[] sourceComponents)
+    {
+        return EntityManager.TryCopyComponents(source, target, meta, sourceComponents);
+    }
+
+    /// <inheritdoc cref="IEntityManager.CopyComponent"/>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    protected IComponent CopyComp(EntityUid source, EntityUid target, IComponent sourceComponent, MetaDataComponent? meta = null)
+    {
+        return EntityManager.CopyComponent(source, target, sourceComponent, meta);
+    }
+
+    /// <inheritdoc cref="IEntityManager.CopyComponent{T}"/>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    protected T CopyComp<T>(EntityUid source, EntityUid target, T sourceComponent, MetaDataComponent? meta = null) where T : IComponent
+    {
+        return EntityManager.CopyComponent(source, target, sourceComponent, meta);
+    }
+
+    /// <inheritdoc cref="IEntityManager.CopyComponents"/>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    protected void CopyComps(EntityUid source, EntityUid target, MetaDataComponent? meta = null, params IComponent[] sourceComponents)
+    {
+        EntityManager.CopyComponents(source, target, meta, sourceComponents);
+    }
+
+    #endregion
+
     #region Component Has
 
     /// <summary>

Robust.Shared/GameObjects/IEntityManager.Components.cs

@@ -358,6 +358,51 @@ namespace Robust.Shared.GameObjects
         /// <returns>If the component existed in the entity.</returns>
         bool TryGetComponent([NotNullWhen(true)] EntityUid? uid, ushort netId, [NotNullWhen(true)] out IComponent? component, MetaDataComponent? meta = null);
 
+        /// <summary>
+        /// Tries to run <see cref="CopyComponents"/> without throwing if the component doesn't exist.
+        /// </summary>
+        bool TryCopyComponent<T>(
+            EntityUid source,
+            EntityUid target,
+            ref T? sourceComponent,
+            [NotNullWhen(true)] out T? targetComp,
+            MetaDataComponent? meta = null) where T : IComponent;
+
+        /// <summary>
+        /// Tries to run <see cref="CopyComponents"/> without throwing if the components don't exist.
+        /// </summary>
+        bool TryCopyComponents(EntityUid source, EntityUid target, MetaDataComponent? meta = null, params Type[] sourceComponents);
+
+        /// <summary>
+        ///     Copy a single component from source to target entity.
+        /// </summary>
+        /// <param name="source">The source entity to copy from.</param>
+        /// <param name="target">The target entity to copy to.</param>
+        /// <param name="sourceComponent">The source component instance to copy.</param>
+        /// <param name="component">The copied component if successful.</param>
+        /// <param name="meta">Optional metadata of the target entity.</param>
+        IComponent CopyComponent(EntityUid source, EntityUid target, IComponent sourceComponent, MetaDataComponent? meta = null);
+
+        /// <summary>
+        ///     Copy a single component from source to target entity.
+        /// </summary>
+        /// <typeparam name="T">The type of component to copy.</typeparam>
+        /// <param name="source">The source entity to copy from.</param>
+        /// <param name="target">The target entity to copy to.</param>
+        /// <param name="sourceComponent">The source component instance to copy.</param>
+        /// <param name="component">The copied component if successful.</param>
+        /// <param name="meta">Optional metadata of the target entity.</param>
+        T CopyComponent<T>(EntityUid source, EntityUid target, T sourceComponent, MetaDataComponent? meta = null) where T : IComponent;
+
+        /// <summary>
+        /// Copy multiple components from source to target entity using existing component instances.
+        /// </summary>
+        /// <param name="source">The source entity to copy from.</param>
+        /// <param name="target">The target entity to copy to.</param>
+        /// <param name="meta">Optional metadata of the target entity.</param>
+        /// <param name="sourceComponents">Array of component instances to copy.</param>
+        void CopyComponents(EntityUid source, EntityUid target, MetaDataComponent? meta = null, params IComponent[] sourceComponents);
+
         /// <summary>
         /// Returns a cached struct enumerator with the specified component.
         /// </summary>

Robust.Shared/GameObjects/Systems/PrototypeReloadSystem.cs

@@ -72,7 +72,9 @@ internal sealed class PrototypeReloadSystem : EntitySystem
         {
             var data = newPrototype.Components[name];
             var component = _componentFactory.GetComponent(name);
-            EntityManager.AddComponent(entity, component);
+
+            if (!EntityManager.HasComponent(entity, component.GetType()))
+                EntityManager.AddComponent(entity, component);
         }
 
         // Update entity metadata

Robust.Shared/GameObjects/Systems/SharedVisibilitySystem.cs

@@ -0,0 +1,26 @@
+namespace Robust.Shared.GameObjects;
+
+public abstract class SharedVisibilitySystem : EntitySystem
+{
+    public virtual void AddLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+    {
+    }
+
+    public virtual void RemoveLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+    {
+    }
+
+    public virtual void SetLayer(Entity<VisibilityComponent?> ent, ushort layer, bool refresh = true)
+    {
+    }
+
+    public virtual void RefreshVisibility(EntityUid uid,
+        VisibilityComponent? visibilityComponent = null,
+        MetaDataComponent? meta = null)
+    {
+    }
+
+    public virtual void RefreshVisibility(Entity<VisibilityComponent?, MetaDataComponent?> ent)
+    {
+    }
+}

Robust.Shared/Network/NetManager.ClientConnect.cs

@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.Linq;
 using System.Net;
 using System.Net.Http;
@@ -11,7 +10,6 @@ using System.Security.Cryptography;
 using System.Threading;
 using System.Threading.Tasks;
 using Lidgren.Network;
-using Robust.Shared.Log;
 using Robust.Shared.Network.Messages.Handshake;
 using Robust.Shared.Utility;
 using SpaceWizards.Sodium;
@@ -98,7 +96,7 @@ namespace Robust.Shared.Network
             {
                 await CCDoHandshake(winningPeer, winningConnection, userNameRequest, mainCancelToken);
             }
-            catch (TaskCanceledException)
+            catch (OperationCanceledException)
             {
                 winningPeer.Peer.Shutdown("Cancelled");
                 _toCleanNetPeers.Add(winningPeer.Peer);
@@ -120,7 +118,10 @@ namespace Robust.Shared.Network
             _logger.Debug("Handshake completed, connection established.");
         }
 
-        private async Task CCDoHandshake(NetPeerData peer, NetConnection connection, string userNameRequest,
+        private async Task CCDoHandshake(
+            NetPeerData peer,
+            NetConnection connection,
+            string userNameRequest,
             CancellationToken cancel)
         {
             var encrypt = _config.GetCVar(CVars.NetEncrypt);
@@ -289,37 +290,51 @@ namespace Robust.Shared.Network
         private async Task<(NetPeerData winningPeer, NetConnection winningConnection)?>
             CCHappyEyeballs(int port, IPAddress first, IPAddress? second, CancellationToken mainCancelToken)
         {
-            NetPeerData CreatePeerForIp(IPAddress address)
+            // Try to establish a connection with an IP address and wait for it to either connect or fail
+            // Returns a disposable wrapper around the peer/connection because ParallelTask
+            async Task<ConnectionAttempt> AttemptConnection(IPAddress address, CancellationToken cancel)
             {
                 var config = _getBaseNetPeerConfig();
-                if (address.AddressFamily == AddressFamily.InterNetworkV6)
-                {
-                    config.LocalAddress = IPAddress.IPv6Any;
-                }
-                else
-                {
-                    config.LocalAddress = IPAddress.Any;
-                }
+                config.LocalAddress = address.AddressFamily == AddressFamily.InterNetworkV6
+                    ? IPAddress.IPv6Any
+                    : IPAddress.Any;
 
                 var peer = new NetPeer(config);
                 peer.Start();
-                var data = new NetPeerData(peer);
-                _netPeers.Add(data);
-                return data;
+                var peerData = new NetPeerData(peer);
+                _netPeers.Add(peerData);
+
+                var connection = peer.Connect(new IPEndPoint(address, port));
+
+                try
+                {
+                    // We need AwaitNonInitStatusChange to properly handle connection state transitions
+                    var reason = await AwaitNonInitStatusChange(connection, cancel);
+
+                    if (connection.Status != NetConnectionStatus.Connected)
+                    {
+                        // Connection failed, clean up and yeet an exception
+                        peer.Shutdown(reason);
+                        _toCleanNetPeers.Add(peer);
+                        throw new Exception($"Connection failed: {reason}");
+                    }
+
+                    return new ConnectionAttempt(peerData, connection, this);
+                }
+                catch (Exception)
+                {
+                    // Something went wrong!
+                    peer.Shutdown("Connection attempt failed");
+                    _toCleanNetPeers.Add(peer);
+                    throw;
+                }
             }
 
-            // Create first peer.
-            var firstPeer = CreatePeerForIp(first);
-            var firstConnection = firstPeer.Peer.Connect(new IPEndPoint(first, port));
-            NetPeerData? secondPeer = null;
-            NetConnection? secondConnection = null;
-            string? secondReason = null;
-
+            // Waits for a connection's status to change from InitiatedConnect to anything else
             async Task<string> AwaitNonInitStatusChange(NetConnection connection, CancellationToken cancellationToken)
             {
-                NetConnectionStatus status;
                 string reason;
-
+                NetConnectionStatus status;
                 do
                 {
                     reason = await AwaitStatusChange(connection, cancellationToken);
@@ -329,124 +344,37 @@ namespace Robust.Shared.Network
                 return reason;
             }
 
-            async Task ConnectSecondDelayed(CancellationToken cancellationToken)
-            {
-                DebugTools.AssertNotNull(second);
-                // Connecting via second peer is delayed by 25ms to give an advantage to IPv6, if it works.
-                var delay = TimeSpan.FromSeconds(_config.GetCVar(CVars.NetHappyEyeballsDelay));
-                await Task.Delay(delay, cancellationToken);
-                if (cancellationToken.IsCancellationRequested)
-                {
-                    return;
-                }
-
-                secondPeer = CreatePeerForIp(second);
-                secondConnection = secondPeer.Peer.Connect(new IPEndPoint(second, port));
-
-                secondReason = await AwaitNonInitStatusChange(secondConnection, cancellationToken);
-            }
-
-            NetPeerData? winningPeer;
-            NetConnection? winningConnection;
-            string? firstReason = null;
             try
             {
-                if (second != null)
-                {
-                    // We have two addresses to try.
-                    var cancellation = CancellationTokenSource.CreateLinkedTokenSource(mainCancelToken);
-                    var firstPeerChanged = AwaitNonInitStatusChange(firstConnection, cancellation.Token);
-                    var secondPeerChanged = ConnectSecondDelayed(cancellation.Token);
+                // Create list of IPs to try
+                var addresses = second != null
+                    ? new[] { first, second }
+                    : new[] { first };
 
-                    var firstChange = await Task.WhenAny(firstPeerChanged, secondPeerChanged);
+                // Use ParallelTask to handle the connection attempts
+                var delay = TimeSpan.FromSeconds(_config.GetCVar(CVars.NetHappyEyeballsDelay));
+                var (result, _) = await HappyEyeballsHttp.ParallelTask(
+                    addresses.Length,
+                    (i, token) => AttemptConnection(addresses[i], token),
+                    delay,
+                    mainCancelToken);
 
-                    if (firstChange == firstPeerChanged)
-                    {
-                        _logger.Debug("First peer status changed.");
-                        // First peer responded first.
-                        if (firstConnection.Status == NetConnectionStatus.Connected)
-                        {
-                            // First peer won!
-                            _logger.Debug("First peer succeeded.");
-                            cancellation.Cancel();
-                            if (secondPeer != null)
-                            {
-                                secondPeer.Peer.Shutdown("First connection attempt won.");
-                                _toCleanNetPeers.Add(secondPeer.Peer);
-                            }
-
-                            winningPeer = firstPeer;
-                            winningConnection = firstConnection;
-                        }
-                        else
-                        {
-                            // First peer failed, try the second one I guess.
-                            _logger.Debug("First peer failed.");
-                            firstPeer.Peer.Shutdown("You failed.");
-                            _toCleanNetPeers.Add(firstPeer.Peer);
-                            firstReason = await firstPeerChanged;
-                            await secondPeerChanged;
-                            winningPeer = secondPeer;
-                            winningConnection = secondConnection;
-                        }
-                    }
-                    else
-                    {
-                        if (secondConnection!.Status == NetConnectionStatus.Connected)
-                        {
-                            // Second peer won!
-                            _logger.Debug("Second peer succeeded.");
-                            cancellation.Cancel();
-                            firstPeer.Peer.Shutdown("Second connection attempt won.");
-                            _toCleanNetPeers.Add(firstPeer.Peer);
-                            winningPeer = secondPeer;
-                            winningConnection = secondConnection;
-                        }
-                        else
-                        {
-                            // First peer failed, try the second one I guess.
-                            _logger.Debug("Second peer failed.");
-                            secondPeer!.Peer.Shutdown("You failed.");
-                            _toCleanNetPeers.Add(secondPeer.Peer);
-                            firstReason = await firstPeerChanged;
-                            winningPeer = firstPeer;
-                            winningConnection = firstConnection;
-                        }
-                    }
-                }
-                else
-                {
-                    // Only one address to try. Pretty straight forward.
-                    firstReason = await AwaitNonInitStatusChange(firstConnection, mainCancelToken);
-                    winningPeer = firstPeer;
-                    winningConnection = firstConnection;
-                }
+                return (result.Peer, result.Connection);
             }
-            catch (TaskCanceledException)
+            catch (OperationCanceledException)
             {
-                firstPeer.Peer.Shutdown("Cancelled");
-                _toCleanNetPeers.Add(firstPeer.Peer);
-                if (secondPeer != null)
-                {
-                    // ReSharper disable once PossibleNullReferenceException
-                    secondPeer.Peer.Shutdown("Cancelled");
-                    _toCleanNetPeers.Add(secondPeer.Peer);
-                }
-
+                // Connection attempt was cancelled, nothing to see here
+                OnConnectFailed("Connection attempt cancelled.");
                 return null;
             }
-
-            // winningPeer can still be failed at this point.
-            // If it is, neither succeeded. RIP.
-            if (winningConnection!.Status != NetConnectionStatus.Connected)
+            catch (AggregateException ae)
             {
-                winningPeer!.Peer.Shutdown("You failed");
-                _toCleanNetPeers.Add(winningPeer.Peer);
-                OnConnectFailed((secondReason ?? firstReason)!);
+                // ParallelTask throws AggregateException with all connection failures
+                // We just take the first one
+                var message = ae.InnerExceptions.First().Message;
+                OnConnectFailed(message);
                 return null;
             }
-
-            return (winningPeer!, winningConnection);
         }
 
         private Task<string> AwaitStatusChange(NetConnection connection, CancellationToken cancellationToken = default)
@@ -471,7 +399,8 @@ namespace Robust.Shared.Network
             return tcs.Task;
         }
 
-        private Task<NetIncomingMessage> AwaitData(NetConnection connection,
+        private Task<NetIncomingMessage> AwaitData(
+            NetConnection connection,
             CancellationToken cancellationToken = default)
         {
             if (_awaitingData.ContainsKey(connection))
@@ -529,5 +458,17 @@ namespace Robust.Shared.Network
         }
 
         private sealed record JoinRequest(string Hash, string? Hwid);
+
+        private sealed class ConnectionAttempt(NetPeerData peer, NetConnection connection, NetManager netManager) : IDisposable
+        {
+            public NetPeerData Peer { get; } = peer;
+            public NetConnection Connection { get; } = connection;
+
+            public void Dispose()
+            {
+                Peer.Peer.Shutdown("Disposing unused connection attempt");
+                netManager._toCleanNetPeers.Add(Peer.Peer);
+            }
+        }
     }
 }

Robust.Shared/Network/NetManager.cs

@@ -587,6 +587,14 @@ namespace Robust.Shared.Network
         public void ClientDisconnect(string reason)
         {
             DebugTools.Assert(IsClient, "Should never be called on the server.");
+
+            // First handle any in-progress connection attempt
+            if (ClientConnectState != ClientConnectionState.NotConnecting)
+            {
+                _cancelConnectTokenSource?.Cancel();
+            }
+
+            // Then handle existing connection if any
             if (ServerChannel != null)
             {
                 Disconnect?.Invoke(this, new NetDisconnectedArgs(ServerChannel, reason));

Robust.Shared/Physics/Systems/SharedJointSystem.cs

@@ -236,7 +236,8 @@ public abstract partial class SharedJointSystem : EntitySystem
         Vector2? anchorB = null,
         string? id = null,
         TransformComponent? xformA = null,
-        TransformComponent? xformB = null)
+        TransformComponent? xformB = null,
+        int? minimumDistance = null)
     {
         if (!Resolve(bodyA, ref xformA) || !Resolve(bodyB, ref xformB))
         {
@@ -246,9 +247,13 @@ public abstract partial class SharedJointSystem : EntitySystem
         anchorA ??= Vector2.Zero;
         anchorB ??= Vector2.Zero;
 
-        var length = Vector2.Transform(anchorA.Value, xformA.WorldMatrix) - Vector2.Transform(anchorB.Value, xformB.WorldMatrix);
+        var vecA = Vector2.Transform(anchorA.Value, xformA.WorldMatrix);
+        var vecB = Vector2.Transform(anchorB.Value, xformB.WorldMatrix);
+        var length = (vecA - vecB).Length();
+        if (minimumDistance != null)
+            length = Math.Max(minimumDistance.Value, length);
 
-        var joint = new DistanceJoint(bodyA, bodyB, anchorA.Value, anchorB.Value, length.Length());
+        var joint = new DistanceJoint(bodyA, bodyB, anchorA.Value, anchorB.Value, length);
         id ??= GetJointId(joint);
         joint.ID = id;
         AddJoint(joint);

Robust.Shared/Properties/AssemblyInfo.cs

@@ -9,7 +9,6 @@
 [assembly: InternalsVisibleTo("Robust.UnitTesting")]
 [assembly: InternalsVisibleTo("OpenToolkit.GraphicsLibraryFramework")]
 [assembly: InternalsVisibleTo("DynamicProxyGenAssembly2")] // Gives access to Castle(Moq)
-[assembly: InternalsVisibleTo("Content.Benchmarks")]
 [assembly: InternalsVisibleTo("Robust.Benchmarks")]
 [assembly: InternalsVisibleTo("Robust.Client.WebView")]
 [assembly: InternalsVisibleTo("Robust.Packaging")]

Robust.Shared/Prototypes/MultiRootInheritanceGraph.cs

@@ -38,6 +38,9 @@ public sealed class MultiRootInheritanceGraph<T> where T : notnull
         //check for circular inheritance
         foreach (var parent in parents)
         {
+            if (EqualityComparer<T>.Default.Equals(parent, id))
+                throw new InvalidOperationException($"Self Inheritance detected for id \"{id}\"!");
+
             var parentsL1 = GetParents(parent);
             if(parentsL1 == null) continue;
 

Robust.Shared/Serialization/NetBitArraySerializer.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.IO;
+using System.Reflection;
+using System.Reflection.Emit;
+using System.Runtime.Serialization;
+using JetBrains.Annotations;
+using NetSerializer;
+
+namespace Robust.Shared.Serialization;
+
+/// <summary>
+/// Custom serializer implementation for <see cref="BitArray"/>.
+/// </summary>
+/// <remarks>
+/// <para>
+/// This type is necessary as, since .NET 10, the internal layout of <see cref="BitArray"/> was changed.
+/// The type now (internally) implements <see cref="ISerializable"/> for backwards compatibility with existing
+/// <c>BinaryFormatter</c> code, but NetSerializer does not support <see cref="ISerializable"/>.
+/// </para>
+/// <para>
+/// This code is designed to be backportable &amp; network compatible with the previous behavior on .NET 9.
+/// </para>
+/// </remarks>
+internal sealed class NetBitArraySerializer : IDynamicTypeSerializer
+{
+    // NOTE: MUST be a IDynamicTypeSerializer for compatibility!
+    // Can be changed in the future.
+
+    // For reference, the layout of BitArray before .NET 10 was:
+    // private int[] m_array;
+    // private int m_length;
+    // private int _version;
+    // NetSerializer serialized these in the following order (sorted by name):
+    // _version, m_array, m_length
+
+    public bool Handles(Type type)
+    {
+        return type == typeof(BitArray);
+    }
+
+    public IEnumerable<Type> GetSubtypes(Type type)
+    {
+        return [typeof(int[]), typeof(int)];
+    }
+
+    public void GenerateWriterMethod(Serializer serializer, Type type, ILGenerator il)
+    {
+        var method = typeof(NetBitArraySerializer).GetMethod("Write", BindingFlags.Static | BindingFlags.NonPublic)!;
+
+        // arg0: Serializer, arg1: Stream, arg2: value
+        il.Emit(OpCodes.Ldarg_0);
+        il.Emit(OpCodes.Ldarg_1);
+        il.Emit(OpCodes.Ldarg_2);
+
+        il.EmitCall(OpCodes.Call, method, null);
+
+        il.Emit(OpCodes.Ret);
+    }
+
+    public void GenerateReaderMethod(Serializer serializer, Type type, ILGenerator il)
+    {
+        var method = typeof(NetBitArraySerializer).GetMethod("Read", BindingFlags.Static | BindingFlags.NonPublic)!;
+
+        // arg0: Serializer, arg1: stream, arg2: out value
+        il.Emit(OpCodes.Ldarg_0);
+        il.Emit(OpCodes.Ldarg_1);
+        il.Emit(OpCodes.Ldarg_2);
+
+        il.EmitCall(OpCodes.Call, method, null);
+
+        il.Emit(OpCodes.Ret);
+    }
+
+    [UsedImplicitly]
+    private static void Write(Serializer serializer, Stream stream, BitArray value)
+    {
+        var intCount = (31 + value.Length) >> 5;
+        var ints = new int[intCount];
+        value.CopyTo(ints, 0);
+
+        serializer.SerializeDirect(stream, 0); // _version
+        serializer.SerializeDirect(stream, ints); // m_array
+        serializer.SerializeDirect(stream, value.Length); // m_length
+    }
+
+    [UsedImplicitly]
+    private static void Read(Serializer serializer, Stream stream, out BitArray value)
+    {
+        serializer.DeserializeDirect<int>(stream, out _); // _version
+        serializer.DeserializeDirect<int[]>(stream, out var array); // m_array
+        serializer.DeserializeDirect<int>(stream, out var length); // m_length
+
+        value = new BitArray(array)
+        {
+            Length = length
+        };
+    }
+}

Robust.Shared/Serialization/RobustSerializer.cs

@@ -91,6 +91,7 @@ namespace Robust.Shared.Serialization
                     MappedStringSerializer.TypeSerializer,
                     new Vector2Serializer(),
                     new Matrix3x2Serializer(),
+                    new NetBitArraySerializer()
                 }
             };
             _serializer = new Serializer(types, settings);

Robust.UnitTesting/Shared/GameObjects/ContainerTests.cs

@@ -91,7 +91,7 @@ namespace Robust.UnitTesting.Shared.GameObjects
                  Assert.That(sContainerSys.Insert(itemUid, container));
 
                  // Modify visibility layer so that the item does not get sent ot the player
-                 sEntManager.System<VisibilitySystem>().AddLayer(itemUid, 10 );
+                 sEntManager.System<SharedVisibilitySystem>().AddLayer(itemUid, 10 );
              });
 
              // Needs minimum 4 to sync to client because buffer size is 3
@@ -119,7 +119,7 @@ namespace Robust.UnitTesting.Shared.GameObjects
              await server.WaitAssertion(() =>
              {
                  // Modify visibility layer so it now gets sent to the client
-                 sEntManager.System<VisibilitySystem>().RemoveLayer(itemUid, 10 );
+                 sEntManager.System<SharedVisibilitySystem>().RemoveLayer(itemUid, 10 );
              });
 
              await server.WaitRunTicks(1);
@@ -219,7 +219,7 @@ namespace Robust.UnitTesting.Shared.GameObjects
                  sContainerSys.Insert(sItemUid, container);
 
                  // Modify visibility layer so that the item does not get sent ot the player
-                 sEntManager.System<VisibilitySystem>().AddLayer(sItemUid, 10 );
+                 sEntManager.System<SharedVisibilitySystem>().AddLayer(sItemUid, 10 );
              });
 
             await server.WaitRunTicks(1);

Robust.UnitTesting/Shared/GameObjects/EntityManagerCopyTests.cs

@@ -0,0 +1,128 @@
+using System.Numerics;
+using NUnit.Framework;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Map;
+using Robust.Shared.Serialization.Manager.Attributes;
+using Robust.UnitTesting.Server;
+
+namespace Robust.UnitTesting.Shared.GameObjects;
+
+[TestFixture]
+public sealed partial class EntityManagerCopyTests
+{
+    [Test]
+    public void CopyComponentGeneric()
+    {
+        var instant = RobustServerSimulation.NewSimulation();
+        instant.RegisterComponents(fac =>
+        {
+            fac.RegisterClass<AComponent>();
+        });
+
+        var sim = instant.InitializeInstance();
+        var entManager = sim.Resolve<IEntityManager>();
+        var mapSystem = entManager.System<SharedMapSystem>();
+
+        mapSystem.CreateMap(out var mapId);
+
+        var original = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        var comp = entManager.AddComponent<AComponent>(original);
+
+        Assert.That(comp.Value, Is.EqualTo(false));
+        comp.Value = true;
+
+        var target = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        Assert.That(!entManager.HasComponent<AComponent>(target));
+
+        var targetComp = entManager.CopyComponent(original, target, comp);
+
+        Assert.That(targetComp!.Owner == target);
+        Assert.That(targetComp.Value, Is.EqualTo(comp.Value));
+        Assert.That(!ReferenceEquals(comp, targetComp));
+    }
+
+    [Test]
+    public void CopyComponentNonGeneric()
+    {
+        var instant = RobustServerSimulation.NewSimulation();
+        instant.RegisterComponents(fac =>
+        {
+            fac.RegisterClass<AComponent>();
+        });
+
+        var sim = instant.InitializeInstance();
+        var entManager = sim.Resolve<IEntityManager>();
+        var mapSystem = entManager.System<SharedMapSystem>();
+
+        mapSystem.CreateMap(out var mapId);
+
+        var original = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        var comp = entManager.AddComponent<AComponent>(original);
+
+        Assert.That(comp.Value, Is.EqualTo(false));
+        comp.Value = true;
+
+        var target = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        Assert.That(!entManager.HasComponent<AComponent>(target));
+
+        var targetComp = entManager.CopyComponent(original, target, (IComponent) comp);
+
+        Assert.That(targetComp!.Owner == target);
+        Assert.That(((AComponent) targetComp).Value, Is.EqualTo(comp.Value));
+        Assert.That(!ReferenceEquals(comp, targetComp));
+    }
+
+    [Test]
+    public void CopyComponentMultiple()
+    {
+        var instant = RobustServerSimulation.NewSimulation();
+        instant.RegisterComponents(fac =>
+        {
+            fac.RegisterClass<AComponent>();
+            fac.RegisterClass<BComponent>();
+        });
+
+        var sim = instant.InitializeInstance();
+        var entManager = sim.Resolve<IEntityManager>();
+        var mapSystem = entManager.System<SharedMapSystem>();
+
+        mapSystem.CreateMap(out var mapId);
+
+        var original = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        var comp = entManager.AddComponent<AComponent>(original);
+        var comp2 = entManager.AddComponent<BComponent>(original);
+
+        Assert.That(comp.Value, Is.EqualTo(false));
+        comp.Value = true;
+
+        var target = entManager.Spawn(null, new MapCoordinates(Vector2.Zero, mapId));
+        Assert.That(!entManager.HasComponent<AComponent>(target));
+
+        entManager.CopyComponents(original, target, null, comp, comp2);
+        var targetComp = entManager.GetComponent<AComponent>(target);
+        var targetComp2 = entManager.GetComponent<BComponent>(target);
+
+        Assert.That(targetComp!.Owner == target);
+        Assert.That(targetComp.Value, Is.EqualTo(comp.Value));
+
+        Assert.That(targetComp2!.Owner == target);
+        Assert.That(targetComp2.Value, Is.EqualTo(comp2.Value));
+
+        Assert.That(!ReferenceEquals(comp, targetComp));
+        Assert.That(!ReferenceEquals(comp2, targetComp2));
+    }
+
+    [DataDefinition]
+    private sealed partial class AComponent : Component
+    {
+        [DataField]
+        public bool Value = false;
+    }
+
+    [DataDefinition]
+    private sealed partial class BComponent : Component
+    {
+        [DataField]
+        public bool Value = false;
+    }
+}

Robust.UnitTesting/Shared/GameObjects/IEntityManagerTests.cs

@@ -1,12 +1,14 @@
+using System.Numerics;
 using NUnit.Framework;
 using Robust.Shared.GameObjects;
 using Robust.Shared.Map;
+using Robust.Shared.Serialization.Manager.Attributes;
 using Robust.UnitTesting.Server;
 
 namespace Robust.UnitTesting.Shared.GameObjects
 {
     [TestFixture, Parallelizable]
-    sealed class EntityManagerTests
+    sealed partial class EntityManagerTests
     {
         private static ISimulation SimulationFactory()
         {

Robust.UnitTesting/Shared/Prototypes/MultiRootGraphTest.cs

@@ -104,4 +104,11 @@ public sealed class MultiRootGraphTest
         Assert.Throws<InvalidOperationException>(() => graph.Add(Id3, new[] { Id1 }));
 
     }
+
+    [Test]
+    public void IsOwnParentTest()
+    {
+        var graph = new MultiRootInheritanceGraph<string>();
+        Assert.Throws<InvalidOperationException>(() => graph.Add(Id1, new []{ Id1 }));
+    }
 }

Robust.UnitTesting/Shared/Resources/WritableDirProviderTest.cs

@@ -24,7 +24,7 @@ namespace Robust.UnitTesting.Shared.Resources
             _testDir = Directory.CreateDirectory(_testDirPath);
             var subDir = Path.Combine(_testDirPath, "writable");
 
-            _dirProvider = new WritableDirProvider(Directory.CreateDirectory(subDir));
+            _dirProvider = new WritableDirProvider(Directory.CreateDirectory(subDir), hideRootDir: false);
         }
 
         [OneTimeTearDown]

Schemas/mapfile.yml

@@ -1,8 +1,18 @@
 # schema file for Yamale
 meta:
   format: int()
-  postmapinit: bool()
+  postmapinit: bool(required=False)
+  time: str(required=False) # timestamp() expects yyyy-mm-dd
+  category: enum("Unknown", "Entity", "Grid", "Map", "Save", required=False) # FileCategory enum
+  engineVersion: str(required=False)
+  entityCount: int(required=False)
+  forkId: str(required=False)
+  forkVersion: str(required=False)
 tilemap: map(str(), key=int())
+orphans: list(int(), required=False)
+nullspace: list(int(), required=False)
+maps: list(int(), required=False)
+grids: list(int(), required=False)
 entities: list(include('proto'), min=1)
 ---
 proto:
@@ -14,64 +24,3 @@ entity:
   components: list(comp())
   missingComponents: list(str(), required=False)
 
-# Example
-# meta:
-#   format: 3
-#   name: DemoStation
-#   author: Space-Wizards
-#   postmapinit: false
-# tilemap:
-#   0: space
-#   1: floor_asteroid_coarse_sand0
-#   2: floor_asteroid_coarse_sand1
-#   3: floor_asteroid_coarse_sand2
-#   4: floor_asteroid_coarse_sand_dug
-#   5: floor_asteroid_sand
-#   6: floor_asteroid_tile
-#   7: floor_blue
-#   8: floor_dark
-#   9: floor_elevator_shaft
-#   10: floor_freezer
-#   11: floor_glass
-#   12: floor_gold
-#   13: floor_green_circuit
-#   14: floor_hydro
-#   15: floor_lino
-#   16: floor_mono
-#   17: floor_reinforced
-#   18: floor_rglass
-#   19: floor_rock_vault
-#   20: floor_showroom
-#   21: floor_snow
-#   22: floor_steel
-#   23: floor_steel_dirty
-#   24: floor_techmaint
-#   25: floor_warning1
-#   26: floor_warning2
-#   27: floor_white
-#   28: floor_white_warning1
-#   29: floor_white_warning2
-#   30: floor_wood
-#   31: lattice
-#   32: plating
-#   33: plating
-# entities:
-# - uid: 0
-#   components:
-#   - parent: null
-#     type: Transform
-#   - index: 0
-#   chunks:
-#   - ind: "-1,-1"
-#     tiles: AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAFgAAAA==
-#     type: MapGrid
-#   - linearDamping: 0.05
-#     fixtures: []
-#     bodyType: Dynamic
-#     type: Physics
-# - uid: 1
-#   type: SpawnPointLatejoin
-#   components:
-#   - parent: 0
-#     pos: 0,0
-#     type: Transform