Added missing deprecation notices to Lua docs

(cherry picked from commit 9f96d0c772)

.github/workflows/ci.yml

@@ -15,10 +15,10 @@ jobs:
 
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Install .NET 6.0
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 
@@ -39,7 +39,7 @@ jobs:
 
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Check Code
         run: |
@@ -57,10 +57,10 @@ jobs:
 
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Install .NET 6.0
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 

.github/workflows/documentation.yml

@@ -1,9 +1,6 @@
 name: Deploy Documentation
 
 on:
-  push:
-    branches: [ bleed ]
-    tags: [ 'release-*', 'playtest-*' ]
   workflow_dispatch:
     inputs:
       tag:
@@ -15,49 +12,18 @@ permissions:
   contents: read  #  to fetch code (actions/checkout)
 
 jobs:
-  prepare:
-    name: Prepare version strings
+  wiki:
+    name: Update Wiki
     if: github.repository == 'openra/openra'
     runs-on: ubuntu-22.04
     steps:
-      - name: Prepare environment variables
-        run: |
-          if [ "${{ github.event_name }}" = "push" ]; then
-            if [ "${{ github.ref_type }}" = "tag" ]; then
-              VERSION_TYPE=`echo "${GITHUB_REF#refs/tags/}" | cut -d"-" -f1`
-              echo "GIT_TAG=${GITHUB_REF#refs/tags/}" >> $GITHUB_ENV
-              echo "VERSION_TYPE=$VERSION_TYPE" >> $GITHUB_ENV
-            else
-              echo "GIT_TAG=bleed" >> $GITHUB_ENV
-              echo "VERSION_TYPE=bleed" >> $GITHUB_ENV
-            fi
-          else
-            VERSION_TYPE=`echo "${{ github.event.inputs.tag }}" | cut -d"-" -f1`
-            echo "GIT_TAG=${{ github.event.inputs.tag }}" >> $GITHUB_ENV
-            echo "VERSION_TYPE=$VERSION_TYPE" >> $GITHUB_ENV
-          fi
-    outputs:
-      git_tag: ${{ env.GIT_TAG }}
-      version_type: ${{ env.VERSION_TYPE }}
-
-  wiki:
-    name: Update Wiki
-    needs: prepare
-    if: github.repository == 'openra/openra' && needs.prepare.outputs.version_type != 'bleed'
-    runs-on: ubuntu-22.04
-    steps:
-      - name: Debug output
-        run: |
-          echo ${{ needs.prepare.outputs.git_tag }}
-          echo ${{ needs.prepare.outputs.version_type }}
-
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
         with:
-          ref: ${{ needs.prepare.outputs.git_tag }}
+          ref: ${{ github.event.inputs.tag }}
 
       - name: Install .NET 6
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 
@@ -66,53 +32,49 @@ jobs:
           make all
 
       - name: Clone Wiki
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
         with:
           repository: openra/openra.wiki
           token: ${{ secrets.DOCS_TOKEN }}
           path: wiki
 
       - name: Update Wiki (Playtest)
-        if: startsWith(needs.prepare.outputs.git_tag, 'playtest-')
+        if: startsWith(github.event.inputs.tag, 'playtest-')
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
         run: |
-          ./utility.sh all --settings-docs "${{ needs.prepare.outputs.git_tag }}" > "wiki/Settings (playtest).md"
+          ./utility.sh all --settings-docs "${GIT_TAG}" > "wiki/Settings (playtest).md"
 
       - name: Update Wiki (Release)
-        if: startsWith(needs.prepare.outputs.git_tag, 'release-')
+        if: startsWith(github.event.inputs.tag, 'release-')
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
         run: |
-          ./utility.sh all --settings-docs "${{ needs.prepare.outputs.git_tag }}" > "wiki/Settings.md"
+          ./utility.sh all --settings-docs "${GIT_TAG}" > "wiki/Settings.md"
 
       - name: Push Wiki
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
         run: |
           cd wiki
           git config --local user.email "actions@github.com"
           git config --local user.name "GitHub Actions"
-          git status
-          git diff-index --quiet HEAD || \
-          (
-            git add --all && \
-            git commit -m "Update auto-generated documentation for ${{ needs.prepare.outputs.git_tag }}" && \
-            git push origin master
-          )
+          git add --all
+          git commit -m "Update auto-generated documentation for ${GIT_TAG}"
+          git push origin master
 
   docs:
     name: Update docs.openra.net
-    needs: prepare
     if: github.repository == 'openra/openra'
     runs-on: ubuntu-22.04
     steps:
-      - name: Debug output
-        run: |
-          echo ${{ needs.prepare.outputs.git_tag }}
-          echo ${{ needs.prepare.outputs.version_type }}
-
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
         with:
-          ref: ${{ needs.prepare.outputs.git_tag }}
+          ref: ${{ github.event.inputs.tag }}
 
       - name: Install .NET 6
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 
@@ -120,31 +82,62 @@ jobs:
         run: |
           make all
 
-      # version_type is release/playtest/bleed - the name of the target branch.
-      - name: Clone docs.openra.net
-        uses: actions/checkout@v4
+      - name: Clone docs.openra.net (Playtest)
+        if: startsWith(github.event.inputs.tag, 'playtest-')
+        uses: actions/checkout@v3
         with:
           repository: openra/docs
           token: ${{ secrets.DOCS_TOKEN }}
           path: docs
-          ref: ${{ needs.prepare.outputs.version_type }}
+          ref: playtest
 
-      - name: Generate docs files
+      - name: Clone docs.openra.net (Release)
+        if: startsWith(github.event.inputs.tag, 'release-')
+        uses: actions/checkout@v3
+        with:
+          repository: openra/docs
+          token: ${{ secrets.DOCS_TOKEN }}
+          path: docs
+          ref: release
+
+      - name: Update docs.openra.net (Playtest)
+        if: startsWith(github.event.inputs.tag, 'playtest-')
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
         run: |
-          ./utility.sh all --docs "${{ needs.prepare.outputs.git_tag }}" | python3 ./packaging/format-docs.py > "docs/api/traits.md"
-          ./utility.sh all --weapon-docs "${{ needs.prepare.outputs.git_tag }}" | python3 ./packaging/format-docs.py > "docs/api/weapons.md"
-          ./utility.sh all --sprite-sequence-docs "${{ needs.prepare.outputs.git_tag }}" | python3 ./packaging/format-docs.py > "docs/api/sprite-sequences.md"
-          ./utility.sh all --lua-docs "${{ needs.prepare.outputs.git_tag }}" > "docs/api/lua.md"
+          ./utility.sh all --docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/traits.md"
+          ./utility.sh all --weapon-docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/weapons.md"
+          ./utility.sh all --sprite-sequence-docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/sprite-sequences.md"
+          ./utility.sh all --lua-docs "${GIT_TAG}" > "docs/api/lua.md"
 
-      - name: Update docs.openra.net
+      - name: Update docs.openra.net (Release)
+        if: startsWith(github.event.inputs.tag, 'release-')
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
+        run: |
+          ./utility.sh all --docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/traits.md"
+          ./utility.sh all --weapon-docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/weapons.md"
+          ./utility.sh all --sprite-sequence-docs "${GIT_TAG}" | python3 ./packaging/format-docs.py > "docs/api/sprite-sequences.md"
+          ./utility.sh all --lua-docs "${GIT_TAG}" > "docs/api/lua.md"
+
+      - name: Commit docs.openra.net
+        env:
+          GIT_TAG: ${{ github.event.inputs.tag }}
         run: |
           cd docs
           git config --local user.email "actions@github.com"
           git config --local user.name "GitHub Actions"
-          git status
-          git diff-index --quiet HEAD || \
-          (
-            git add api/*.md && \
-            git commit -m "Update auto-generated documentation for ${{ needs.prepare.outputs.git_tag }}" && \
-            git push origin ${{ needs.prepare.outputs.version_type }}
-          )
+          git add api/*.md
+          git commit -m "Update auto-generated documentation for ${GIT_TAG}"
+
+      - name: Push docs.openra.net (Release)
+        if: startsWith(github.event.inputs.tag, 'release-')
+        run: |
+          cd docs
+          git push origin release
+
+      - name: Push docs.openra.net (Playtest)
+        if: startsWith(github.event.inputs.tag, 'playtest-')
+        run: |
+          cd docs
+          git push origin playtest

.github/workflows/packaging.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Prepare Environment
         run: echo "GIT_TAG=${GITHUB_REF#refs/tags/}" >> ${GITHUB_ENV}
@@ -40,10 +40,10 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Install .NET 6.0
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 
@@ -70,10 +70,10 @@ jobs:
     runs-on: macos-11
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Install .NET 6.0
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 
@@ -105,10 +105,10 @@ jobs:
     runs-on: ubuntu-22.04
     steps:
       - name: Clone Repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v3
 
       - name: Install .NET 6.0
-        uses: actions/setup-dotnet@v4
+        uses: actions/setup-dotnet@v3
         with:
           dotnet-version: '6.0.x'
 

AUTHORS

@@ -150,7 +150,6 @@ Also thanks to:
     * Teemu Nieminen (Temeez)
     * Thomas Christlieb (ThomasChr)
     * Tim Mylemans (gecko)
-    * Tinix
     * Tirili
     * Tomas Einarsson (Mesacer)
     * Tom van Leth (tovl)

Directory.Build.props

@@ -33,7 +33,7 @@
     <Optimize>false</Optimize>
     <!-- Enable only for Debug builds to improve compile-time performance for Release builds -->
     <EnforceCodeStyleInBuild>true</EnforceCodeStyleInBuild>
-    <!-- Enabling GenerateDocumentationFile is required for IDE0005 (Remove unnecessary import)
+    <!-- Enabling GenerateDocumentationFile is required for IDE0005 (Remove unnecessary import) 
       rule to run in command line builds. https://github.com/dotnet/roslyn/issues/41640
       Enable only for Debug builds to improve compile-time performance for Release builds -->
     <GenerateDocumentationFile>true</GenerateDocumentationFile>
@@ -51,10 +51,8 @@
     </ItemGroup>
   </Target>
 
-  <!-- StyleCop/Roslynator -->
+  <!-- StyleCop -->
   <ItemGroup>
     <PackageReference Include="StyleCop.Analyzers" Version="1.2.0-beta.435" PrivateAssets="All" />
-    <!-- Roslynator analyzers fail to run under Mono (AD0001) -->
-    <PackageReference Include="Roslynator.Analyzers" Version="4.2.0" PrivateAssets="All" Condition="'$(MSBuildRuntimeType)'!='Mono'" />
   </ItemGroup>
 </Project>

OpenRA.Game/Activities/Activity.cs

@@ -146,22 +146,18 @@ namespace OpenRA.Activities
 		}
 
 		/// <summary>
-		/// <para>
 		/// Called every tick to run activity logic. Returns false if the activity should
 		/// remain active, or true if it is complete. Cancelled activities must ensure they
 		/// return the actor to a consistent state before returning true.
-		/// </para>
-		/// <para>
+		///
 		/// Child activities can be queued using QueueChild, and these will be ticked
 		/// instead of the parent while they are active. Activities that need to run logic
 		/// in parallel with child activities should set ChildHasPriority to false and
 		/// manually call TickChildren.
-		/// </para>
-		/// <para>
+		///
 		/// Queuing one or more child activities and returning true is valid, and causes
 		/// the activity to be completed immediately (without ticking again) once the
 		/// children have completed.
-		/// </para>
 		/// </summary>
 		public virtual bool Tick(Actor self)
 		{
@@ -226,11 +222,10 @@ namespace OpenRA.Activities
 		}
 
 		/// <summary>
-		/// <para>Prints the activity tree, starting from the top or optionally from a given origin.</para>
-		/// <para>
+		/// Prints the activity tree, starting from the top or optionally from a given origin.
+		///
 		/// Call this method from any place that's called during a tick, such as the Tick() method itself or
 		/// the Before(First|Last)Run() methods. The origin activity will be marked in the output.
-		/// </para>
 		/// </summary>
 		/// <param name="self">The actor performing this activity.</param>
 		/// <param name="origin">Activity from which to start traversing, and which to mark. If null, mark the calling activity, and start traversal from the top.</param>

OpenRA.Game/Actor.cs

@@ -71,12 +71,7 @@ namespace OpenRA
 		public IEffectiveOwner EffectiveOwner { get; }
 		public IOccupySpace OccupiesSpace { get; }
 		public ITargetable[] Targetables { get; }
-		public IEnumerable<ITargetablePositions> EnabledTargetablePositions { get; }
-		readonly ICrushable[] crushables;
-		public ICrushable[] Crushables
-		{
-			get => crushables ?? throw new InvalidOperationException($"Crushables for {Info.Name} are not initialized.");
-		}
+		public IEnumerable<ITargetablePositions> EnabledTargetablePositions { get; private set; }
 
 		public bool IsIdle => CurrentActivity == null;
 		public bool IsDead => Disposed || (health != null && health.IsDead);
@@ -160,7 +155,6 @@ namespace OpenRA
 				var targetablesList = new List<ITargetable>();
 				var targetablePositionsList = new List<ITargetablePositions>();
 				var syncHashesList = new List<SyncHash>();
-				var crushablesList = new List<ICrushable>();
 
 				foreach (var traitInfo in Info.TraitsInConstructOrder())
 				{
@@ -187,7 +181,6 @@ namespace OpenRA
 					{ if (trait is ITargetable t) targetablesList.Add(t); }
 					{ if (trait is ITargetablePositions t) targetablePositionsList.Add(t); }
 					{ if (trait is ISync t) syncHashesList.Add(new SyncHash(t)); }
-					{ if (trait is ICrushable t) crushablesList.Add(t); }
 				}
 
 				resolveOrders = resolveOrdersList.ToArray();
@@ -202,7 +195,6 @@ namespace OpenRA
 				EnabledTargetablePositions = targetablePositions.Where(Exts.IsTraitEnabled);
 				enabledTargetableWorldPositions = EnabledTargetablePositions.SelectMany(tp => tp.TargetablePositions(this));
 				SyncHashes = syncHashesList.ToArray();
-				crushables = crushablesList.ToArray();
 			}
 		}
 

OpenRA.Game/CVec.cs

@@ -61,14 +61,14 @@ namespace OpenRA
 
 		public static readonly CVec[] Directions =
 		{
-			new(-1, -1),
-			new(-1,  0),
-			new(-1,  1),
-			new(0, -1),
-			new(0,  1),
-			new(1, -1),
-			new(1,  0),
-			new(1,  1),
+			new CVec(-1, -1),
+			new CVec(-1,  0),
+			new CVec(-1,  1),
+			new CVec(0, -1),
+			new CVec(0,  1),
+			new CVec(1, -1),
+			new CVec(1,  0),
+			new CVec(1,  1),
 		};
 
 		#region Scripting interface

OpenRA.Game/CryptoUtil.cs

@@ -22,9 +22,6 @@ namespace OpenRA
 		// Fixed byte pattern for the OID header
 		static readonly byte[] OIDHeader = { 0x30, 0xD, 0x6, 0x9, 0x2A, 0x86, 0x48, 0x86, 0xF7, 0xD, 0x1, 0x1, 0x1, 0x5, 0x0 };
 
-		static readonly char[] HexUpperAlphabet = "0123456789ABCDEF".ToArray();
-		static readonly char[] HexLowerAlphabet = "0123456789abcdef".ToArray();
-
 		public static string PublicKeyFingerprint(RSAParameters parameters)
 		{
 			// Public key fingerprint is defined as the SHA1 of the modulus + exponent bytes
@@ -56,33 +53,33 @@ namespace OpenRA
 				using (var s = new MemoryStream(data))
 				{
 					// SEQUENCE
-					s.ReadUInt8();
+					s.ReadByte();
 					ReadTLVLength(s);
 
 					// SEQUENCE -> fixed header junk
-					s.ReadUInt8();
+					s.ReadByte();
 					var headerLength = ReadTLVLength(s);
 					s.Position += headerLength;
 
 					// SEQUENCE -> BIT_STRING
-					s.ReadUInt8();
+					s.ReadByte();
 					ReadTLVLength(s);
-					s.ReadUInt8();
+					s.ReadByte();
 
 					// SEQUENCE -> BIT_STRING -> SEQUENCE
-					s.ReadUInt8();
+					s.ReadByte();
 					ReadTLVLength(s);
 
 					// SEQUENCE -> BIT_STRING -> SEQUENCE -> INTEGER (modulus)
-					s.ReadUInt8();
+					s.ReadByte();
 					var modulusLength = ReadTLVLength(s);
-					s.ReadUInt8();
+					s.ReadByte();
 					var modulus = s.ReadBytes(modulusLength - 1);
 
 					// SEQUENCE -> BIT_STRING -> SEQUENCE -> INTEGER (exponent)
-					s.ReadUInt8();
+					s.ReadByte();
 					var exponentLength = ReadTLVLength(s);
-					s.ReadUInt8();
+					s.ReadByte();
 					var exponent = s.ReadBytes(exponentLength - 1);
 
 					return new RSAParameters
@@ -161,13 +158,13 @@ namespace OpenRA
 
 		static int ReadTLVLength(Stream s)
 		{
-			var length = s.ReadUInt8();
+			var length = s.ReadByte();
 			if (length < 0x80)
 				return length;
 
-			Span<byte> data = stackalloc byte[4];
-			s.ReadBytes(data[..Math.Min(length & 0x7F, 4)]);
-			return BitConverter.ToInt32(data);
+			var data = new byte[4];
+			s.ReadBytes(data, 0, Math.Min(length & 0x7F, 4));
+			return BitConverter.ToInt32(data.ToArray(), 0);
 		}
 
 		static int TripletFullLength(int dataLength)
@@ -252,44 +249,19 @@ namespace OpenRA
 
 		public static string SHA1Hash(Stream data)
 		{
-			using var csp = SHA1.Create();
-			return ToHex(csp.ComputeHash(data), true);
+			using (var csp = SHA1.Create())
+				return new string(csp.ComputeHash(data).SelectMany(a => a.ToString("x2")).ToArray());
 		}
 
 		public static string SHA1Hash(byte[] data)
 		{
-			using var csp = SHA1.Create();
-			return ToHex(csp.ComputeHash(data), true);
+			using (var csp = SHA1.Create())
+				return new string(csp.ComputeHash(data).SelectMany(a => a.ToString("x2")).ToArray());
 		}
 
 		public static string SHA1Hash(string data)
 		{
 			return SHA1Hash(Encoding.UTF8.GetBytes(data));
 		}
-
-		public static string ToHex(ReadOnlySpan<byte> source, bool lowerCase = false)
-		{
-			if (source.Length == 0)
-				return string.Empty;
-
-			// excessively avoid stack overflow if source is too large (considering that we're allocating a new string)
-			var buffer = source.Length <= 256 ? stackalloc char[source.Length * 2] : new char[source.Length * 2];
-			return ToHexInternal(source, buffer, lowerCase);
-		}
-
-		static string ToHexInternal(ReadOnlySpan<byte> source, Span<char> buffer, bool lowerCase)
-		{
-			var sourceIndex = 0;
-			var alphabet = lowerCase ? HexLowerAlphabet : HexUpperAlphabet;
-
-			for (var i = 0; i < buffer.Length; i += 2)
-			{
-				var b = source[sourceIndex++];
-				buffer[i] = alphabet[b >> 4];
-				buffer[i + 1] = alphabet[b & 0xF];
-			}
-
-			return new string(buffer);
-		}
 	}
 }

OpenRA.Game/ExternalMods.cs

@@ -66,7 +66,6 @@ namespace OpenRA
 			// Several types of support directory types are available, depending on
 			// how the player has installed and launched the game.
 			// Read registration metadata from all of them
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			foreach (var source in GetSupportDirs(ModRegistration.User | ModRegistration.System))
 			{
 				var metadataPath = Path.Combine(source, "ModMetadata");
@@ -77,7 +76,7 @@ namespace OpenRA
 				{
 					try
 					{
-						var yaml = MiniYaml.FromFile(path, stringPool: stringPool).First().Value;
+						var yaml = MiniYaml.FromStream(File.OpenRead(path), path).First().Value;
 						LoadMod(yaml, path);
 					}
 					catch (Exception e)
@@ -95,17 +94,17 @@ namespace OpenRA
 
 			if (sheetBuilder != null)
 			{
-				var iconNode = yaml.NodeWithKeyOrDefault("Icon");
+				var iconNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon");
 				if (iconNode != null && !string.IsNullOrEmpty(iconNode.Value.Value))
 					using (var stream = new MemoryStream(Convert.FromBase64String(iconNode.Value.Value)))
 						mod.Icon = sheetBuilder.Add(new Png(stream));
 
-				var icon2xNode = yaml.NodeWithKeyOrDefault("Icon2x");
+				var icon2xNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon2x");
 				if (icon2xNode != null && !string.IsNullOrEmpty(icon2xNode.Value.Value))
 					using (var stream = new MemoryStream(Convert.FromBase64String(icon2xNode.Value.Value)))
 						mod.Icon2x = sheetBuilder.Add(new Png(stream), 1f / 2);
 
-				var icon3xNode = yaml.NodeWithKeyOrDefault("Icon3x");
+				var icon3xNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon3x");
 				if (icon3xNode != null && !string.IsNullOrEmpty(icon3xNode.Value.Value))
 					using (var stream = new MemoryStream(Convert.FromBase64String(icon3xNode.Value.Value)))
 						mod.Icon3x = sheetBuilder.Add(new Png(stream), 1f / 3);
@@ -123,7 +122,7 @@ namespace OpenRA
 				return;
 
 			var key = ExternalMod.MakeKey(mod);
-			var yaml = new MiniYamlNode("Registration", new MiniYaml("", new[]
+			var yaml = new MiniYamlNode("Registration", new MiniYaml("", new List<MiniYamlNode>()
 			{
 				new MiniYamlNode("Id", mod.Id),
 				new MiniYamlNode("Version", mod.Metadata.Version),
@@ -132,21 +131,17 @@ namespace OpenRA
 				new MiniYamlNode("LaunchArgs", new[] { "Game.Mod=" + mod.Id }.Concat(launchArgs).JoinWith(", "))
 			}));
 
-			var iconNodes = new List<MiniYamlNode>();
-
 			using (var stream = mod.Package.GetStream("icon.png"))
 				if (stream != null)
-					iconNodes.Add(new MiniYamlNode("Icon", Convert.ToBase64String(stream.ReadAllBytes())));
+					yaml.Value.Nodes.Add(new MiniYamlNode("Icon", Convert.ToBase64String(stream.ReadAllBytes())));
 
 			using (var stream = mod.Package.GetStream("icon-2x.png"))
 				if (stream != null)
-					iconNodes.Add(new MiniYamlNode("Icon2x", Convert.ToBase64String(stream.ReadAllBytes())));
+					yaml.Value.Nodes.Add(new MiniYamlNode("Icon2x", Convert.ToBase64String(stream.ReadAllBytes())));
 
 			using (var stream = mod.Package.GetStream("icon-3x.png"))
 				if (stream != null)
-					iconNodes.Add(new MiniYamlNode("Icon3x", Convert.ToBase64String(stream.ReadAllBytes())));
-
-			yaml = yaml.WithValue(yaml.Value.WithNodesAppended(iconNodes));
+					yaml.Value.Nodes.Add(new MiniYamlNode("Icon3x", Convert.ToBase64String(stream.ReadAllBytes())));
 
 			var sources = new HashSet<string>();
 			if (registration.HasFlag(ModRegistration.System))
@@ -206,7 +201,7 @@ namespace OpenRA
 					string modKey = null;
 					try
 					{
-						var yaml = MiniYaml.FromFile(path).First().Value;
+						var yaml = MiniYaml.FromStream(File.OpenRead(path), path).First().Value;
 						var m = FieldLoader.Load<ExternalMod>(yaml);
 						modKey = ExternalMod.MakeKey(m);
 

OpenRA.Game/Exts.cs

@@ -22,14 +22,15 @@ namespace OpenRA
 {
 	public static class Exts
 	{
-		public static string FormatInvariant(this string format, params object[] args)
+		public static bool IsUppercase(this string str)
 		{
-			return string.Format(CultureInfo.InvariantCulture, format, args);
+			return string.Compare(str.ToUpperInvariant(), str, false) == 0;
 		}
 
-		public static string FormatCurrent(this string format, params object[] args)
+		public static T WithDefault<T>(T def, Func<T> f)
 		{
-			return string.Format(CultureInfo.CurrentCulture, format, args);
+			try { return f(); }
+			catch { return def; }
 		}
 
 		public static Lazy<T> Lazy<T>(Func<T> p) { return new Lazy<T>(p); }
@@ -130,35 +131,11 @@ namespace OpenRA
 			return ret;
 		}
 
-		public static T GetOrAdd<T>(this HashSet<T> set, T value)
-		{
-			if (!set.TryGetValue(value, out var ret))
-				set.Add(ret = value);
-			return ret;
-		}
-
-		public static T GetOrAdd<T>(this HashSet<T> set, T value, Func<T, T> createFn)
-		{
-			if (!set.TryGetValue(value, out var ret))
-				set.Add(ret = createFn(value));
-			return ret;
-		}
-
 		public static int IndexOf<T>(this T[] array, T value)
 		{
 			return Array.IndexOf(array, value);
 		}
 
-		public static T FirstOrDefault<T>(this T[] array, Predicate<T> match)
-		{
-			return Array.Find(array, match);
-		}
-
-		public static T FirstOrDefault<T>(this List<T> list, Predicate<T> match)
-		{
-			return list.Find(match);
-		}
-
 		public static T Random<T>(this IEnumerable<T> ts, MersenneTwister r)
 		{
 			return Random(ts, r, true);
@@ -171,7 +148,7 @@ namespace OpenRA
 
 		static T Random<T>(IEnumerable<T> ts, MersenneTwister r, bool throws)
 		{
-			var xs = ts as IReadOnlyCollection<T>;
+			var xs = ts as ICollection<T>;
 			xs ??= ts.ToList();
 			if (xs.Count == 0)
 			{
@@ -326,9 +303,9 @@ namespace OpenRA
 
 			// Adjust for other rounding modes
 			if (round == ISqrtRoundMode.Nearest && remainder > root)
-				root++;
+				root += 1;
 			else if (round == ISqrtRoundMode.Ceiling && root * root < number)
-				root++;
+				root += 1;
 
 			return root;
 		}
@@ -367,9 +344,9 @@ namespace OpenRA
 
 			// Adjust for other rounding modes
 			if (round == ISqrtRoundMode.Nearest && remainder > root)
-				root++;
+				root += 1;
 			else if (round == ISqrtRoundMode.Ceiling && root * root < number)
-				root++;
+				root += 1;
 
 			return root;
 		}
@@ -379,11 +356,6 @@ namespace OpenRA
 			return number * 46341 / 32768;
 		}
 
-		public static int MultiplyBySqrtTwoOverTwo(int number)
-		{
-			return (int)(number * 23170L / 32768L);
-		}
-
 		public static int IntegerDivisionRoundingAwayFromZero(int dividend, int divisor)
 		{
 			var quotient = Math.DivRem(dividend, divisor, out var remainder);
@@ -521,22 +493,17 @@ namespace OpenRA
 			return result;
 		}
 
-		public static byte ParseByteInvariant(string s)
-		{
-			return byte.Parse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo);
-		}
-
-		public static short ParseInt16Invariant(string s)
-		{
-			return short.Parse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo);
-		}
-
-		public static int ParseInt32Invariant(string s)
+		public static int ParseIntegerInvariant(string s)
 		{
 			return int.Parse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo);
 		}
 
-		public static bool TryParseInt32Invariant(string s, out int i)
+		public static byte ParseByte(string s)
+		{
+			return byte.Parse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo);
+		}
+
+		public static bool TryParseIntegerInvariant(string s, out int i)
 		{
 			return int.TryParse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo, out i);
 		}
@@ -546,26 +513,6 @@ namespace OpenRA
 			return long.TryParse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo, out i);
 		}
 
-		public static string ToStringInvariant(this byte i)
-		{
-			return i.ToString(NumberFormatInfo.InvariantInfo);
-		}
-
-		public static string ToStringInvariant(this byte i, string format)
-		{
-			return i.ToString(format, NumberFormatInfo.InvariantInfo);
-		}
-
-		public static string ToStringInvariant(this int i)
-		{
-			return i.ToString(NumberFormatInfo.InvariantInfo);
-		}
-
-		public static string ToStringInvariant(this int i, string format)
-		{
-			return i.ToString(format, NumberFormatInfo.InvariantInfo);
-		}
-
 		public static bool IsTraitEnabled<T>(this T trait)
 		{
 			return trait is not IDisabledTrait disabledTrait || !disabledTrait.IsTraitDisabled;
@@ -615,6 +562,11 @@ namespace OpenRA
 		{
 			return new LineSplitEnumerator(str.AsSpan(), separator);
 		}
+
+		public static bool TryParseInt32Invariant(string s, out int i)
+		{
+			return int.TryParse(s, NumberStyles.Integer, NumberFormatInfo.InvariantInfo, out i);
+		}
 	}
 
 	public ref struct LineSplitEnumerator
@@ -629,7 +581,7 @@ namespace OpenRA
 			Current = default;
 		}
 
-		public readonly LineSplitEnumerator GetEnumerator() => this;
+		public LineSplitEnumerator GetEnumerator() => this;
 
 		public bool MoveNext()
 		{

OpenRA.Game/FieldLoader.cs

@@ -87,7 +87,6 @@ namespace OpenRA
 				{ typeof(WAngle), ParseWAngle },
 				{ typeof(WRot), ParseWRot },
 				{ typeof(CPos), ParseCPos },
-				{ typeof(CPos[]), ParseCPosArray },
 				{ typeof(CVec), ParseCVec },
 				{ typeof(CVec[]), ParseCVecArray },
 				{ typeof(BooleanExpression), ParseBooleanExpression },
@@ -119,7 +118,7 @@ namespace OpenRA
 
 		static object ParseInt(string fieldName, Type fieldType, string value, MemberInfo field)
 		{
-			if (Exts.TryParseInt32Invariant(value, out var res))
+			if (Exts.TryParseIntegerInvariant(value, out var res))
 			{
 				if (res >= 0 && res < BoxedInts.Length)
 					return BoxedInts[res];
@@ -196,11 +195,11 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma);
-				if (parts.Length == 3
-					&& WDist.TryParse(parts[0], out var rx)
-					&& WDist.TryParse(parts[1], out var ry)
-					&& WDist.TryParse(parts[2], out var rz))
-					return new WVec(rx, ry, rz);
+				if (parts.Length == 3)
+				{
+					if (WDist.TryParse(parts[0], out var rx) && WDist.TryParse(parts[1], out var ry) && WDist.TryParse(parts[2], out var rz))
+						return new WVec(rx, ry, rz);
+				}
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -220,8 +219,8 @@ namespace OpenRA
 				for (var i = 0; i < vecs.Length; ++i)
 				{
 					if (WDist.TryParse(parts[3 * i], out var rx)
-						&& WDist.TryParse(parts[3 * i + 1], out var ry)
-						&& WDist.TryParse(parts[3 * i + 2], out var rz))
+							&& WDist.TryParse(parts[3 * i + 1], out var ry)
+							&& WDist.TryParse(parts[3 * i + 2], out var rz))
 						vecs[i] = new WVec(rx, ry, rz);
 				}
 
@@ -236,11 +235,13 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma);
-				if (parts.Length == 3
-					&& WDist.TryParse(parts[0], out var rx)
-					&& WDist.TryParse(parts[1], out var ry)
-					&& WDist.TryParse(parts[2], out var rz))
-					return new WPos(rx, ry, rz);
+				if (parts.Length == 3)
+				{
+					if (WDist.TryParse(parts[0], out var rx)
+						&& WDist.TryParse(parts[1], out var ry)
+						&& WDist.TryParse(parts[2], out var rz))
+						return new WPos(rx, ry, rz);
+				}
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -248,7 +249,7 @@ namespace OpenRA
 
 		static object ParseWAngle(string fieldName, Type fieldType, string value, MemberInfo field)
 		{
-			if (Exts.TryParseInt32Invariant(value, out var res))
+			if (Exts.TryParseIntegerInvariant(value, out var res))
 				return new WAngle(res);
 			return InvalidValueAction(value, fieldType, fieldName);
 		}
@@ -258,11 +259,13 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma);
-				if (parts.Length == 3
-					&& Exts.TryParseInt32Invariant(parts[0], out var rr)
-					&& Exts.TryParseInt32Invariant(parts[1], out var rp)
-					&& Exts.TryParseInt32Invariant(parts[2], out var ry))
-					return new WRot(new WAngle(rr), new WAngle(rp), new WAngle(ry));
+				if (parts.Length == 3)
+				{
+					if (Exts.TryParseIntegerInvariant(parts[0], out var rr)
+							&& Exts.TryParseIntegerInvariant(parts[1], out var rp)
+							&& Exts.TryParseIntegerInvariant(parts[2], out var ry))
+						return new WRot(new WAngle(rr), new WAngle(rp), new WAngle(ry));
+				}
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -275,33 +278,10 @@ namespace OpenRA
 				var parts = value.Split(SplitComma, StringSplitOptions.RemoveEmptyEntries);
 				if (parts.Length == 3)
 					return new CPos(
-						Exts.ParseInt32Invariant(parts[0]),
-						Exts.ParseInt32Invariant(parts[1]),
-						Exts.ParseByteInvariant(parts[2]));
-				return new CPos(Exts.ParseInt32Invariant(parts[0]), Exts.ParseInt32Invariant(parts[1]));
-			}
-
-			return InvalidValueAction(value, fieldType, fieldName);
-		}
-
-		static object ParseCPosArray(string fieldName, Type fieldType, string value, MemberInfo field)
-		{
-			if (value != null)
-			{
-				var parts = value.Split(SplitComma);
-
-				if (parts.Length % 2 != 0)
-					return InvalidValueAction(value, fieldType, fieldName);
-
-				var vecs = new CPos[parts.Length / 2];
-				for (var i = 0; i < vecs.Length; i++)
-				{
-					if (int.TryParse(parts[2 * i], out var rx)
-							&& int.TryParse(parts[2 * i + 1], out var ry))
-						vecs[i] = new CPos(rx, ry);
-				}
-
-				return vecs;
+						Exts.ParseIntegerInvariant(parts[0]),
+						Exts.ParseIntegerInvariant(parts[1]),
+						Exts.ParseByte(parts[2]));
+				return new CPos(Exts.ParseIntegerInvariant(parts[0]), Exts.ParseIntegerInvariant(parts[1]));
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -312,7 +292,7 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma, StringSplitOptions.RemoveEmptyEntries);
-				return new CVec(Exts.ParseInt32Invariant(parts[0]), Exts.ParseInt32Invariant(parts[1]));
+				return new CVec(Exts.ParseIntegerInvariant(parts[0]), Exts.ParseIntegerInvariant(parts[1]));
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -405,7 +385,7 @@ namespace OpenRA
 
 				var ints = new int2[parts.Length / 2];
 				for (var i = 0; i < ints.Length; i++)
-					ints[i] = new int2(Exts.ParseInt32Invariant(parts[2 * i]), Exts.ParseInt32Invariant(parts[2 * i + 1]));
+					ints[i] = new int2(Exts.ParseIntegerInvariant(parts[2 * i]), Exts.ParseIntegerInvariant(parts[2 * i + 1]));
 
 				return ints;
 			}
@@ -418,7 +398,7 @@ namespace OpenRA
 			if (value != null)
 			{
 				var parts = value.Split(SplitComma, StringSplitOptions.RemoveEmptyEntries);
-				return new Size(Exts.ParseInt32Invariant(parts[0]), Exts.ParseInt32Invariant(parts[1]));
+				return new Size(Exts.ParseIntegerInvariant(parts[0]), Exts.ParseIntegerInvariant(parts[1]));
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -432,7 +412,7 @@ namespace OpenRA
 				if (parts.Length != 2)
 					return InvalidValueAction(value, fieldType, fieldName);
 
-				return new int2(Exts.ParseInt32Invariant(parts[0]), Exts.ParseInt32Invariant(parts[1]));
+				return new int2(Exts.ParseIntegerInvariant(parts[0]), Exts.ParseIntegerInvariant(parts[1]));
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -480,10 +460,10 @@ namespace OpenRA
 			{
 				var parts = value.Split(SplitComma, StringSplitOptions.RemoveEmptyEntries);
 				return new Rectangle(
-					Exts.ParseInt32Invariant(parts[0]),
-					Exts.ParseInt32Invariant(parts[1]),
-					Exts.ParseInt32Invariant(parts[2]),
-					Exts.ParseInt32Invariant(parts[3]));
+					Exts.ParseIntegerInvariant(parts[0]),
+					Exts.ParseIntegerInvariant(parts[1]),
+					Exts.ParseIntegerInvariant(parts[2]),
+					Exts.ParseIntegerInvariant(parts[3]));
 			}
 
 			return InvalidValueAction(value, fieldType, fieldName);
@@ -520,7 +500,7 @@ namespace OpenRA
 			if (yaml == null)
 				return Activator.CreateInstance(fieldType);
 
-			var dict = Activator.CreateInstance(fieldType, yaml.Nodes.Length);
+			var dict = Activator.CreateInstance(fieldType, yaml.Nodes.Count);
 			var arguments = fieldType.GetGenericArguments();
 			var addMethod = fieldType.GetMethod(nameof(Dictionary<object, object>.Add), arguments);
 			var addArgs = new object[2];
@@ -551,7 +531,7 @@ namespace OpenRA
 			if (string.IsNullOrEmpty(value))
 				return null;
 
-			var innerType = fieldType.GetGenericArguments()[0];
+			var innerType = fieldType.GetGenericArguments().First();
 			var innerValue = GetValue("Nullable<T>", innerType, value, field);
 			return fieldType.GetConstructor(new[] { innerType }).Invoke(new[] { innerValue });
 		}

OpenRA.Game/FieldSaver.cs

@@ -15,7 +15,6 @@ using System.ComponentModel;
 using System.Globalization;
 using System.Linq;
 using System.Reflection;
-using System.Text;
 using OpenRA.Primitives;
 
 namespace OpenRA
@@ -59,7 +58,7 @@ namespace OpenRA
 
 			return new MiniYaml(
 				null,
-				fields.Select(info => new MiniYamlNode(info.YamlName, FormatValue(o, info.Field))));
+				fields.Select(info => new MiniYamlNode(info.YamlName, FormatValue(o, info.Field))).ToList());
 		}
 
 		public static MiniYamlNode SaveField(object o, string field)
@@ -85,7 +84,7 @@ namespace OpenRA
 			// This is only for documentation generation
 			if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Dictionary<,>))
 			{
-				var result = new StringBuilder();
+				var result = "";
 				var dict = (System.Collections.IDictionary)v;
 				foreach (var kvp in dict)
 				{
@@ -95,10 +94,10 @@ namespace OpenRA
 					var formattedKey = FormatValue(key);
 					var formattedValue = FormatValue(value);
 
-					result.Append($"{formattedKey}: {formattedValue}{Environment.NewLine}");
+					result += $"{formattedKey}: {formattedValue}{Environment.NewLine}";
 				}
 
-				return result.ToString();
+				return result;
 			}
 
 			if (v is DateTime d)

OpenRA.Game/FileFormats/Png.cs

@@ -16,7 +16,6 @@ using System.Linq;
 using System.Net;
 using System.Text;
 using ICSharpCode.SharpZipLib.Checksum;
-using ICSharpCode.SharpZipLib.Zip.Compression;
 using ICSharpCode.SharpZipLib.Zip.Compression.Streams;
 using OpenRA.Graphics;
 using OpenRA.Primitives;
@@ -46,13 +45,12 @@ namespace OpenRA.FileFormats
 			var data = new List<byte>();
 			Type = SpriteFrameType.Rgba32;
 
-			byte bitDepth = 8;
 			while (true)
 			{
 				var length = IPAddress.NetworkToHostOrder(s.ReadInt32());
-				var type = s.ReadASCII(4);
+				var type = Encoding.UTF8.GetString(s.ReadBytes(4));
 				var content = s.ReadBytes(length);
-				s.ReadInt32(); // crc
+				/*var crc = */s.ReadInt32();
 
 				if (!headerParsed && type != "IHDR")
 					throw new InvalidDataException("Invalid PNG file - header does not appear first.");
@@ -68,7 +66,7 @@ namespace OpenRA.FileFormats
 							Width = IPAddress.NetworkToHostOrder(ms.ReadInt32());
 							Height = IPAddress.NetworkToHostOrder(ms.ReadInt32());
 
-							bitDepth = ms.ReadUInt8();
+							var bitDepth = ms.ReadUInt8();
 							var colorType = (PngColorType)ms.ReadUInt8();
 							if (IsPaletted(bitDepth, colorType))
 								Type = SpriteFrameType.Indexed8;
@@ -78,7 +76,7 @@ namespace OpenRA.FileFormats
 							Data = new byte[Width * Height * PixelStride];
 
 							var compression = ms.ReadUInt8();
-							ms.ReadUInt8(); // filter
+							/*var filter = */ms.ReadUInt8();
 							var interlace = ms.ReadUInt8();
 
 							if (compression != 0)
@@ -94,8 +92,8 @@ namespace OpenRA.FileFormats
 
 						case "PLTE":
 						{
-							Palette = new Color[length / 3];
-							for (var i = 0; i < Palette.Length; i++)
+							Palette = new Color[256];
+							for (var i = 0; i < length / 3; i++)
 							{
 								var r = ms.ReadUInt8(); var g = ms.ReadUInt8(); var b = ms.ReadUInt8();
 								Palette[i] = Color.FromArgb(r, g, b);
@@ -138,34 +136,14 @@ namespace OpenRA.FileFormats
 								{
 									var pxStride = PixelStride;
 									var rowStride = Width * pxStride;
-									var pixelsPerByte = 8 / bitDepth;
-									var sourceRowStride = Exts.IntegerDivisionRoundingAwayFromZero(rowStride, pixelsPerByte);
 
 									Span<byte> prevLine = new byte[rowStride];
 									for (var y = 0; y < Height; y++)
 									{
 										var filter = (PngFilter)ds.ReadUInt8();
-										ds.ReadBytes(Data, y * rowStride, sourceRowStride);
+										ds.ReadBytes(Data, y * rowStride, rowStride);
 										var line = Data.AsSpan(y * rowStride, rowStride);
 
-										// If the source has a bit depth of 1, 2 or 4 it packs multiple pixels per byte.
-										// Unpack to bit depth of 8, yielding 1 pixel per byte.
-										// This makes life easier for consumers of palleted data.
-										if (bitDepth < 8)
-										{
-											var mask = 0xFF >> (8 - bitDepth);
-											for (var i = sourceRowStride - 1; i >= 0; i--)
-											{
-												var packed = line[i];
-												for (var j = 0; j < pixelsPerByte; j++)
-												{
-													var dest = i * pixelsPerByte + j;
-													if (dest < line.Length) // Guard against last byte being only partially packed
-														line[dest] = (byte)(packed >> (8 - (j + 1) * bitDepth) & mask);
-												}
-											}
-										}
-
 										switch (filter)
 										{
 											case PngFilter.None:
@@ -291,7 +269,7 @@ namespace OpenRA.FileFormats
 
 		static bool IsPaletted(byte bitDepth, PngColorType colorType)
 		{
-			if (bitDepth <= 8 && colorType == (PngColorType.Indexed | PngColorType.Color))
+			if (bitDepth == 8 && colorType == (PngColorType.Indexed | PngColorType.Color))
 				return true;
 
 			if (bitDepth == 8 && colorType == (PngColorType.Color | PngColorType.Alpha))
@@ -309,10 +287,10 @@ namespace OpenRA.FileFormats
 
 			var typeBytes = Encoding.ASCII.GetBytes(type);
 			output.Write(IPAddress.HostToNetworkOrder((int)input.Length));
-			output.Write(typeBytes);
+			output.WriteArray(typeBytes);
 
 			var data = input.ReadAllBytes();
-			output.Write(data);
+			output.WriteArray(data);
 
 			var crc32 = new Crc32();
 			crc32.Update(typeBytes);
@@ -324,7 +302,7 @@ namespace OpenRA.FileFormats
 		{
 			using (var output = new MemoryStream())
 			{
-				output.Write(Signature);
+				output.WriteArray(Signature);
 				using (var header = new MemoryStream())
 				{
 					header.Write(IPAddress.HostToNetworkOrder(Width));
@@ -372,14 +350,13 @@ namespace OpenRA.FileFormats
 
 				using (var data = new MemoryStream())
 				{
-					using (var compressed = new DeflaterOutputStream(data, new Deflater(Deflater.BEST_COMPRESSION)))
+					using (var compressed = new DeflaterOutputStream(data))
 					{
 						var rowStride = Width * PixelStride;
 						for (var y = 0; y < Height; y++)
 						{
-							// Assuming no filtering for simplicity
-							const byte FilterType = 0;
-							compressed.WriteByte(FilterType);
+							// Write uncompressed scanlines for simplicity
+							compressed.WriteByte(0);
 							compressed.Write(Data, y * rowStride, rowStride);
 						}
 
@@ -394,7 +371,7 @@ namespace OpenRA.FileFormats
 				{
 					using (var text = new MemoryStream())
 					{
-						text.Write(Encoding.ASCII.GetBytes(kv.Key + (char)0 + kv.Value));
+						text.WriteArray(Encoding.ASCII.GetBytes(kv.Key + (char)0 + kv.Value));
 						WritePngChunk(output, "tEXt", text);
 					}
 				}

OpenRA.Game/FileFormats/ReplayMetadata.cs

@@ -47,8 +47,8 @@ namespace OpenRA.FileFormats
 				throw new NotSupportedException($"Metadata version {version} is not supported");
 
 			// Read game info (max 100K limit as a safeguard against corrupted files)
-			var data = fs.ReadLengthPrefixedString(Encoding.UTF8, 1024 * 100);
-			GameInfo = GameInformation.Deserialize(data, path);
+			var data = fs.ReadString(Encoding.UTF8, 1024 * 100);
+			GameInfo = GameInformation.Deserialize(data);
 		}
 
 		public void Write(BinaryWriter writer)
@@ -62,7 +62,7 @@ namespace OpenRA.FileFormats
 			{
 				// Write lobby info data
 				writer.Flush();
-				dataLength += writer.BaseStream.WriteLengthPrefixedString(Encoding.UTF8, GameInfo.Serialize());
+				dataLength += writer.BaseStream.WriteString(Encoding.UTF8, GameInfo.Serialize());
 			}
 
 			// Write total length & end marker

OpenRA.Game/FileSystem/FileSystem.cs

@@ -83,14 +83,14 @@ namespace OpenRA.FileSystem
 
 		public void Mount(string name, string explicitName = null)
 		{
-			var optional = name.StartsWith('~');
+			var optional = name.StartsWith("~", StringComparison.Ordinal);
 			if (optional)
 				name = name[1..];
 
 			try
 			{
 				IReadOnlyPackage package;
-				if (name.StartsWith('$'))
+				if (name.StartsWith("$", StringComparison.Ordinal))
 				{
 					name = name[1..];
 
@@ -109,8 +109,10 @@ namespace OpenRA.FileSystem
 
 				Mount(package, explicitName);
 			}
-			catch when (optional)
+			catch
 			{
+				if (!optional)
+					throw;
 			}
 		}
 
@@ -159,7 +161,9 @@ namespace OpenRA.FileSystem
 					explicitMounts.Remove(key);
 
 				// Mod packages aren't owned by us, so we shouldn't dispose them
-				if (!modPackages.Remove(package))
+				if (modPackages.Contains(package))
+					modPackages.Remove(package);
+				else
 					package.Dispose();
 			}
 			else
@@ -186,12 +190,6 @@ namespace OpenRA.FileSystem
 			UnmountAll();
 			foreach (var kv in manifest.Packages)
 				Mount(kv.Key, kv.Value);
-
-			mountedPackages.TrimExcess();
-			explicitMounts.TrimExcess();
-			modPackages.TrimExcess();
-			foreach (var packages in fileIndex.Values)
-				packages.TrimExcess();
 		}
 
 		Stream GetFromCache(string filename)
@@ -228,11 +226,14 @@ namespace OpenRA.FileSystem
 		public bool TryOpen(string filename, out Stream s)
 		{
 			var explicitSplit = filename.IndexOf('|');
-			if (explicitSplit > 0 && explicitMounts.TryGetValue(filename[..explicitSplit], out var explicitPackage))
+			if (explicitSplit > 0)
 			{
-				s = explicitPackage.GetStream(filename[(explicitSplit + 1)..]);
-				if (s != null)
-					return true;
+				if (explicitMounts.TryGetValue(filename[..explicitSplit], out var explicitPackage))
+				{
+					s = explicitPackage.GetStream(filename[(explicitSplit + 1)..]);
+					if (s != null)
+						return true;
+				}
 			}
 
 			s = GetFromCache(filename);
@@ -261,10 +262,10 @@ namespace OpenRA.FileSystem
 		public bool Exists(string filename)
 		{
 			var explicitSplit = filename.IndexOf('|');
-			if (explicitSplit > 0 &&
-				explicitMounts.TryGetValue(filename[..explicitSplit], out var explicitPackage) &&
-				explicitPackage.Contains(filename[(explicitSplit + 1)..]))
-				return true;
+			if (explicitSplit > 0)
+				if (explicitMounts.TryGetValue(filename[..explicitSplit], out var explicitPackage))
+					if (explicitPackage.Contains(filename[(explicitSplit + 1)..]))
+						return true;
 
 			return fileIndex.ContainsKey(filename);
 		}
@@ -294,7 +295,7 @@ namespace OpenRA.FileSystem
 		public static string ResolveAssemblyPath(string path, Manifest manifest, InstalledMods installedMods)
 		{
 			var explicitSplit = path.IndexOf('|');
-			if (explicitSplit > 0 && !path.StartsWith('^'))
+			if (explicitSplit > 0 && !path.StartsWith("^"))
 			{
 				var parent = path[..explicitSplit];
 				var filename = path[(explicitSplit + 1)..];
@@ -303,7 +304,7 @@ namespace OpenRA.FileSystem
 				if (parentPath == null)
 					return null;
 
-				if (parentPath.StartsWith('$'))
+				if (parentPath.StartsWith("$", StringComparison.Ordinal))
 				{
 					if (!installedMods.TryGetValue(parentPath[1..], out var mod))
 						return null;

OpenRA.Game/FileSystem/Folder.cs

@@ -84,7 +84,7 @@ namespace OpenRA.FileSystem
 			// in FileSystem.OpenPackage.  Their internal name therefore contains the
 			// full parent path too.  We need to be careful to not add a second path
 			// prefix to these hacked packages.
-			var filePath = filename.StartsWith(Name, StringComparison.Ordinal) ? filename : Path.Combine(Name, filename);
+			var filePath = filename.StartsWith(Name) ? filename : Path.Combine(Name, filename);
 
 			Directory.CreateDirectory(Path.GetDirectoryName(filePath));
 			using (var s = File.Create(filePath))
@@ -98,7 +98,7 @@ namespace OpenRA.FileSystem
 			// in FileSystem.OpenPackage.  Their internal name therefore contains the
 			// full parent path too.  We need to be careful to not add a second path
 			// prefix to these hacked packages.
-			var filePath = filename.StartsWith(Name, StringComparison.Ordinal) ? filename : Path.Combine(Name, filename);
+			var filePath = filename.StartsWith(Name) ? filename : Path.Combine(Name, filename);
 			if (Directory.Exists(filePath))
 				Directory.Delete(filePath, true);
 			else if (File.Exists(filePath))

OpenRA.Game/FileSystem/ZipFile.cs

@@ -21,7 +21,7 @@ namespace OpenRA.FileSystem
 	{
 		const uint ZipSignature = 0x04034b50;
 
-		public class ReadOnlyZipFile : IReadOnlyPackage
+		class ReadOnlyZipFile : IReadOnlyPackage
 		{
 			public string Name { get; protected set; }
 			protected ZipFile pkg;
@@ -68,7 +68,6 @@ namespace OpenRA.FileSystem
 			public void Dispose()
 			{
 				pkg?.Close();
-				GC.SuppressFinalize(this);
 			}
 
 			public IReadOnlyPackage OpenPackage(string filename, FileSystem context)
@@ -94,7 +93,7 @@ namespace OpenRA.FileSystem
 			}
 		}
 
-		public sealed class ReadWriteZipFile : ReadOnlyZipFile, IReadWritePackage
+		sealed class ReadWriteZipFile : ReadOnlyZipFile, IReadWritePackage
 		{
 			readonly MemoryStream pkgStream = new();
 
@@ -118,7 +117,10 @@ namespace OpenRA.FileSystem
 
 			void Commit()
 			{
-				File.WriteAllBytes(Name, pkgStream.ToArray());
+				var pos = pkgStream.Position;
+				pkgStream.Position = 0;
+				File.WriteAllBytes(Name, pkgStream.ReadBytes((int)pkgStream.Length));
+				pkgStream.Position = pos;
 			}
 
 			public void Update(string filename, byte[] contents)
@@ -145,7 +147,7 @@ namespace OpenRA.FileSystem
 
 			public ZipFolder(ReadOnlyZipFile parent, string path)
 			{
-				if (path.EndsWith('/'))
+				if (path.EndsWith("/", StringComparison.Ordinal))
 					path = path[..^1];
 
 				Name = path;

OpenRA.Game/Game.cs

@@ -180,7 +180,6 @@ namespace OpenRA
 		}
 
 		public static event Action BeforeGameStart = () => { };
-		public static event Action AfterGameStart = () => { };
 		internal static void StartGame(string mapUID, WorldType type)
 		{
 			// Dispose of the old world before creating a new one.
@@ -224,12 +223,6 @@ namespace OpenRA
 			//   Much better to clean up now then to drop frames during gameplay for GC pauses.
 			GCSettings.LargeObjectHeapCompactionMode = GCLargeObjectHeapCompactionMode.CompactOnce;
 			GC.Collect();
-
-			// PostLoadComplete is designed for anything that should trigger at the very end of loading.
-			// e.g. audio notifications that the game is starting.
-			OrderManager.World.PostLoadComplete(worldRenderer);
-
-			AfterGameStart();
 		}
 
 		public static void RestartGame()
@@ -423,7 +416,7 @@ namespace OpenRA
 
 				// Sanitize input from platform-specific launchers
 				// Process.Start requires paths to not be quoted, even if they contain spaces
-				if (launchPath != null && launchPath[0] == '"' && launchPath.Last() == '"')
+				if (launchPath != null && launchPath.First() == '"' && launchPath.Last() == '"')
 					launchPath = launchPath[1..^1];
 
 				// Metadata registration requires an explicit launch path
@@ -531,11 +524,10 @@ namespace OpenRA
 				.Where(m => m.Status == MapStatus.Available && m.Visibility.HasFlag(MapVisibility.Shellmap))
 				.Select(m => m.Uid);
 
-			var shellmap = shellmaps.RandomOrDefault(CosmeticRandom);
-			if (shellmap == null)
+			if (!shellmaps.Any())
 				throw new InvalidDataException("No valid shellmaps available");
 
-			return shellmap;
+			return shellmaps.Random(CosmeticRandom);
 		}
 
 		public static void SwitchToExternalMod(ExternalMod mod, string[] launchArguments = null, Action onFailed = null)
@@ -609,10 +601,7 @@ namespace OpenRA
 
 			if (orderManager.LastTickTime.ShouldAdvance(tick))
 			{
-				if (orderManager.GameStarted && orderManager.LocalFrameNumber == 0)
-					PerfHistory.Reset(); // Remove history that occurred whilst the new game was loading.
-
-				using (var sample = new PerfSample("tick_time"))
+				using (new PerfSample("tick_time"))
 				{
 					orderManager.LastTickTime.AdvanceTickTime(tick);
 
@@ -621,11 +610,7 @@ namespace OpenRA
 					Sync.RunUnsynced(world, orderManager.TickImmediate);
 
 					if (world == null)
-					{
-						if (orderManager.GameStarted)
-							PerfHistory.Reset(); // Remove old history when a new game starts.
 						return;
-					}
 
 					if (orderManager.TryTick())
 					{
@@ -679,7 +664,7 @@ namespace OpenRA
 				// Prepare renderables (i.e. render voxels) before calling BeginFrame
 				using (new PerfSample("render_prepare"))
 				{
-					worldRenderer?.BeginFrame();
+					Renderer.WorldModelRenderer.BeginFrame();
 
 					// World rendering is disabled while the loading screen is displayed
 					if (worldRenderer != null && !worldRenderer.World.IsLoadingGameSave)
@@ -689,7 +674,7 @@ namespace OpenRA
 					}
 
 					Ui.PrepareRenderables();
-					worldRenderer?.EndFrame();
+					Renderer.WorldModelRenderer.EndFrame();
 				}
 
 				// worldRenderer is null during the initial install/download screen
@@ -793,7 +778,7 @@ namespace OpenRA
 				var logicWorld = worldRenderer?.World;
 
 				// ReplayTimestep = 0 means the replay is paused: we need to keep logicInterval as UI.Timestep to avoid breakage
-				if (logicWorld != null && (!logicWorld.IsReplay || logicWorld.ReplayTimestep != 0))
+				if (logicWorld != null && !(logicWorld.IsReplay && logicWorld.ReplayTimestep == 0))
 					logicInterval = logicWorld == OrderManager.World ? OrderManager.SuggestedTimestep : logicWorld.Timestep;
 
 				// Ideal time between screen updates
@@ -928,15 +913,15 @@ namespace OpenRA
 		{
 			var endpoints = new List<IPEndPoint>
 			{
-				new(IPAddress.IPv6Any, settings.ListenPort),
-				new(IPAddress.Any, settings.ListenPort)
+				new IPEndPoint(IPAddress.IPv6Any, settings.ListenPort),
+				new IPEndPoint(IPAddress.Any, settings.ListenPort)
 			};
 			server = new Server.Server(endpoints, settings, ModData, ServerType.Multiplayer);
 
 			return server.GetEndpointForLocalConnection();
 		}
 
-		public static ConnectionTarget CreateLocalServer(string map, bool isSkirmish = false)
+		public static ConnectionTarget CreateLocalServer(string map)
 		{
 			var settings = new ServerSettings()
 			{
@@ -950,9 +935,9 @@ namespace OpenRA
 			// This would break the Restart button, which relies on the PlayerIndex always being the same for local servers
 			var endpoints = new List<IPEndPoint>
 			{
-				new(IPAddress.Loopback, 0)
+				new IPEndPoint(IPAddress.Loopback, 0)
 			};
-			server = new Server.Server(endpoints, settings, ModData, isSkirmish ? ServerType.Skirmish : ServerType.Local);
+			server = new Server.Server(endpoints, settings, ModData, ServerType.Local);
 
 			return server.GetEndpointForLocalConnection();
 		}

OpenRA.Game/GameInformation.cs

@@ -49,13 +49,13 @@ namespace OpenRA
 			playersByRuntime = new Dictionary<OpenRA.Player, Player>();
 		}
 
-		public static GameInformation Deserialize(string data, string path)
+		public static GameInformation Deserialize(string data)
 		{
 			try
 			{
 				var info = new GameInformation();
 
-				var nodes = MiniYaml.FromString(data, path);
+				var nodes = MiniYaml.FromString(data);
 				foreach (var node in nodes)
 				{
 					var keyParts = node.Key.Split('@');
@@ -85,7 +85,7 @@ namespace OpenRA
 		{
 			var nodes = new List<MiniYamlNode>
 			{
-				new("Root", FieldSaver.Save(this))
+				new MiniYamlNode("Root", FieldSaver.Save(this))
 			};
 
 			for (var i = 0; i < Players.Count; i++)

OpenRA.Game/GameRules/ActorInfo.cs

@@ -22,7 +22,7 @@ namespace OpenRA
 	/// </summary>
 	public class ActorInfo
 	{
-		public const char AbstractActorPrefix = '^';
+		public const string AbstractActorPrefix = "^";
 		public const char TraitInstanceSeparator = '@';
 
 		/// <summary>
@@ -130,7 +130,6 @@ namespace OpenRA
 
 			// Continue resolving traits as long as possible.
 			// Each time we resolve some traits, this means dependencies for other traits may then be possible to satisfy in the next pass.
-#pragma warning disable CA1851 // Possible multiple enumerations of 'IEnumerable' collection
 			var readyToResolve = more.ToList();
 			while (readyToResolve.Count != 0)
 			{
@@ -139,7 +138,6 @@ namespace OpenRA
 				readyToResolve.Clear();
 				readyToResolve.AddRange(more);
 			}
-#pragma warning restore CA1851
 
 			if (unresolved.Count != 0)
 			{
@@ -162,7 +160,7 @@ namespace OpenRA
 				throw new YamlException(exceptionString);
 			}
 
-			constructOrderCache = resolved.ConvertAll(r => r.Trait);
+			constructOrderCache = resolved.Select(r => r.Trait).ToList();
 			return constructOrderCache;
 		}
 
@@ -187,7 +185,7 @@ namespace OpenRA
 		public bool HasTraitInfo<T>() where T : ITraitInfoInterface { return traits.Contains<T>(); }
 		public T TraitInfo<T>() where T : ITraitInfoInterface { return traits.Get<T>(); }
 		public T TraitInfoOrDefault<T>() where T : ITraitInfoInterface { return traits.GetOrDefault<T>(); }
-		public IReadOnlyCollection<T> TraitInfos<T>() where T : ITraitInfoInterface { return traits.WithInterface<T>(); }
+		public IEnumerable<T> TraitInfos<T>() where T : ITraitInfoInterface { return traits.WithInterface<T>(); }
 
 		public BitSet<TargetableType> GetAllTargetTypes()
 		{

OpenRA.Game/GameRules/Ruleset.cs

@@ -124,7 +124,7 @@ namespace OpenRA
 			{
 				var actors = MergeOrDefault("Manifest,Rules", fs, m.Rules, null, null,
 					k => new ActorInfo(modData.ObjectCreator, k.Key.ToLowerInvariant(), k.Value),
-					filterNode: n => n.Key.StartsWith(ActorInfo.AbstractActorPrefix));
+					filterNode: n => n.Key.StartsWith(ActorInfo.AbstractActorPrefix, StringComparison.Ordinal));
 
 				var weapons = MergeOrDefault("Manifest,Weapons", fs, m.Weapons, null, null,
 					k => new WeaponInfo(k.Value));
@@ -182,7 +182,7 @@ namespace OpenRA
 			{
 				var actors = MergeOrDefault("Rules", fileSystem, m.Rules, mapRules, dr.Actors,
 					k => new ActorInfo(modData.ObjectCreator, k.Key.ToLowerInvariant(), k.Value),
-					filterNode: n => n.Key.StartsWith(ActorInfo.AbstractActorPrefix));
+					filterNode: n => n.Key.StartsWith(ActorInfo.AbstractActorPrefix, StringComparison.Ordinal));
 
 				var weapons = MergeOrDefault("Weapons", fileSystem, m.Weapons, mapWeapons, dr.Weapons,
 					k => new WeaponInfo(k.Value));
@@ -226,10 +226,10 @@ namespace OpenRA
 
 		static bool AnyCustomYaml(MiniYaml yaml)
 		{
-			return yaml != null && (yaml.Value != null || yaml.Nodes.Length > 0);
+			return yaml != null && (yaml.Value != null || yaml.Nodes.Count > 0);
 		}
 
-		static bool AnyFlaggedTraits(ModData modData, IEnumerable<MiniYamlNode> actors)
+		static bool AnyFlaggedTraits(ModData modData, List<MiniYamlNode> actors)
 		{
 			foreach (var actorNode in actors)
 			{
@@ -260,18 +260,18 @@ namespace OpenRA
 				return true;
 
 			// Any trait overrides that aren't explicitly whitelisted are flagged
-			if (mapRules == null)
-				return false;
-
-			if (AnyFlaggedTraits(modData, mapRules.Nodes))
-				return true;
-
-			if (mapRules.Value != null)
+			if (mapRules != null)
 			{
-				var mapFiles = FieldLoader.GetValue<string[]>("value", mapRules.Value);
-				foreach (var f in mapFiles)
-					if (AnyFlaggedTraits(modData, MiniYaml.FromStream(fileSystem.Open(f), f)))
-						return true;
+				if (AnyFlaggedTraits(modData, mapRules.Nodes))
+					return true;
+
+				if (mapRules.Value != null)
+				{
+					var mapFiles = FieldLoader.GetValue<string[]>("value", mapRules.Value);
+					foreach (var f in mapFiles)
+						if (AnyFlaggedTraits(modData, MiniYaml.FromStream(fileSystem.Open(f), f)))
+							return true;
+				}
 			}
 
 			return false;

OpenRA.Game/GameRules/SoundInfo.cs

@@ -40,16 +40,16 @@ namespace OpenRA.GameRules
 		static Dictionary<string, SoundPool> ParseSoundPool(MiniYaml y, string key)
 		{
 			var ret = new Dictionary<string, SoundPool>();
-			var classifiction = y.NodeWithKey(key);
+			var classifiction = y.Nodes.First(x => x.Key == key);
 			foreach (var t in classifiction.Value.Nodes)
 			{
 				var volumeModifier = 1f;
-				var volumeModifierNode = t.Value.NodeWithKeyOrDefault(nameof(SoundPool.VolumeModifier));
+				var volumeModifierNode = t.Value.Nodes.FirstOrDefault(x => x.Key == nameof(SoundPool.VolumeModifier));
 				if (volumeModifierNode != null)
 					volumeModifier = FieldLoader.GetValue<float>(volumeModifierNode.Key, volumeModifierNode.Value.Value);
 
 				var interruptType = SoundPool.DefaultInterruptType;
-				var interruptTypeNode = t.Value.NodeWithKeyOrDefault(nameof(SoundPool.InterruptType));
+				var interruptTypeNode = t.Value.Nodes.FirstOrDefault(x => x.Key == nameof(SoundPool.InterruptType));
 				if (interruptTypeNode != null)
 					interruptType = FieldLoader.GetValue<SoundPool.InterruptType>(interruptTypeNode.Key, interruptTypeNode.Value.Value);
 

OpenRA.Game/GameRules/WeaponInfo.cs

@@ -139,14 +139,13 @@ namespace OpenRA.GameRules
 		{
 			// Resolve any weapon-level yaml inheritance or removals
 			// HACK: The "Defaults" sequence syntax prevents us from doing this generally during yaml parsing
-			content = content.WithNodes(MiniYaml.Merge(new IReadOnlyCollection<MiniYamlNode>[] { content.Nodes }));
+			content.Nodes = MiniYaml.Merge(new[] { content.Nodes });
 			FieldLoader.Load(this, content);
 		}
 
 		static object LoadProjectile(MiniYaml yaml)
 		{
-			var proj = yaml.NodeWithKeyOrDefault("Projectile")?.Value;
-			if (proj == null)
+			if (!yaml.ToDictionary().TryGetValue("Projectile", out var proj))
 				return null;
 
 			var ret = Game.CreateObject<IProjectileInfo>(proj.Value + "Info");
@@ -160,7 +159,7 @@ namespace OpenRA.GameRules
 		static object LoadWarheads(MiniYaml yaml)
 		{
 			var retList = new List<IWarhead>();
-			foreach (var node in yaml.Nodes.Where(n => n.Key.StartsWith("Warhead", StringComparison.Ordinal)))
+			foreach (var node in yaml.Nodes.Where(n => n.Key.StartsWith("Warhead")))
 			{
 				var ret = Game.CreateObject<IWarhead>(node.Value.Value + "Warhead");
 				if (ret == null)

OpenRA.Game/GameSpeed.cs

@@ -10,6 +10,7 @@
 #endregion
 
 using System.Collections.Generic;
+using System.Linq;
 
 namespace OpenRA
 {
@@ -37,7 +38,7 @@ namespace OpenRA
 		static object LoadSpeeds(MiniYaml y)
 		{
 			var ret = new Dictionary<string, GameSpeed>();
-			var speedsNode = y.NodeWithKeyOrDefault("Speeds");
+			var speedsNode = y.Nodes.FirstOrDefault(n => n.Key == "Speeds");
 			if (speedsNode == null)
 				throw new YamlException("Error parsing GameSpeeds: Missing Speeds node!");
 

OpenRA.Game/Graphics/ChromeProvider.cs

@@ -77,12 +77,11 @@ namespace OpenRA.Graphics
 			cachedPanelSprites = new Dictionary<string, Sprite[]>();
 			cachedCollectionSheets = new Dictionary<Collection, (Sheet, int)>();
 
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var chrome = MiniYaml.Merge(modData.Manifest.Chrome
-				.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool)));
+				.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s)));
 
 			foreach (var c in chrome)
-				if (!c.Key.StartsWith('^'))
+				if (!c.Key.StartsWith("^", StringComparison.Ordinal))
 					LoadCollection(c.Key, c.Value);
 		}
 
@@ -235,7 +234,7 @@ namespace OpenRA.Graphics
 			{
 				// PERF: We don't need to search for images if there are no definitions.
 				// PERF: It's more efficient to send an empty array rather than an array of 9 nulls.
-				if (collection.Regions.Count == 0)
+				if (!collection.Regions.Any())
 					return Array.Empty<Sprite>();
 
 				// Support manual definitions for unusual dialog layouts

OpenRA.Game/Graphics/CursorProvider.cs

@@ -24,11 +24,10 @@ namespace OpenRA.Graphics
 		public CursorProvider(ModData modData)
 		{
 			var fileSystem = modData.DefaultFileSystem;
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 			var sequenceYaml = MiniYaml.Merge(modData.Manifest.Cursors.Select(
-				s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool)));
+				s => MiniYaml.FromStream(fileSystem.Open(s), s)));
 
-			var cursorsYaml = new MiniYaml(null, sequenceYaml).NodeWithKey("Cursors").Value;
+			var nodesDict = new MiniYaml(null, sequenceYaml).ToDictionary();
 
 			// Overwrite previous definitions if there are duplicates
 			var pals = new Dictionary<string, IProvidesCursorPaletteInfo>();
@@ -36,14 +35,14 @@ namespace OpenRA.Graphics
 				if (p.Palette != null)
 					pals[p.Palette] = p;
 
-			Palettes = cursorsYaml.Nodes.Select(n => n.Value.Value)
+			Palettes = nodesDict["Cursors"].Nodes.Select(n => n.Value.Value)
 				.Where(p => p != null)
 				.Distinct()
 				.ToDictionary(p => p, p => pals[p].ReadPalette(modData.DefaultFileSystem));
 
 			var frameCache = new FrameCache(fileSystem, modData.SpriteLoaders);
 			var cursors = new Dictionary<string, CursorSequence>();
-			foreach (var s in cursorsYaml.Nodes)
+			foreach (var s in nodesDict["Cursors"].Nodes)
 				foreach (var sequence in s.Value.Nodes)
 					cursors.Add(sequence.Key, new CursorSequence(frameCache, sequence.Key, s.Key, s.Value.Value, sequence.Value));
 

OpenRA.Game/Graphics/CursorSequence.cs

@@ -27,7 +27,7 @@ namespace OpenRA.Graphics
 		{
 			var d = info.ToDictionary();
 
-			Start = Exts.ParseInt32Invariant(d["Start"].Value);
+			Start = Exts.ParseIntegerInvariant(d["Start"].Value);
 			Palette = palette;
 			Name = name;
 
@@ -38,9 +38,9 @@ namespace OpenRA.Graphics
 				(d.TryGetValue("End", out yaml) && yaml.Value == "*"))
 				Length = Frames.Length;
 			else if (d.TryGetValue("Length", out yaml))
-				Length = Exts.ParseInt32Invariant(yaml.Value);
+				Length = Exts.ParseIntegerInvariant(yaml.Value);
 			else if (d.TryGetValue("End", out yaml))
-				Length = Exts.ParseInt32Invariant(yaml.Value) - Start;
+				Length = Exts.ParseIntegerInvariant(yaml.Value) - Start;
 			else
 				Length = 1;
 
@@ -54,13 +54,13 @@ namespace OpenRA.Graphics
 
 			if (d.TryGetValue("X", out yaml))
 			{
-				Exts.TryParseInt32Invariant(yaml.Value, out var x);
+				Exts.TryParseIntegerInvariant(yaml.Value, out var x);
 				Hotspot = Hotspot.WithX(x);
 			}
 
 			if (d.TryGetValue("Y", out yaml))
 			{
-				Exts.TryParseInt32Invariant(yaml.Value, out var y);
+				Exts.TryParseIntegerInvariant(yaml.Value, out var y);
 				Hotspot = Hotspot.WithY(y);
 			}
 		}

OpenRA.Game/Graphics/MarkerTileRenderable.cs

@@ -1,56 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.Linq;
-using OpenRA.Primitives;
-
-namespace OpenRA.Graphics
-{
-	public class MarkerTileRenderable : IRenderable, IFinalizedRenderable
-	{
-		readonly CPos pos;
-		readonly Color color;
-
-		public MarkerTileRenderable(CPos pos, Color color)
-		{
-			this.pos = pos;
-			this.color = color;
-		}
-
-		public WPos Pos => WPos.Zero;
-		public int ZOffset => 0;
-		public bool IsDecoration => true;
-
-		public IRenderable WithZOffset(int newOffset) { return this; }
-
-		public IRenderable OffsetBy(in WVec vec)
-		{
-			return new MarkerTileRenderable(pos, color);
-		}
-
-		public IRenderable AsDecoration() { return this; }
-
-		public IFinalizedRenderable PrepareRender(WorldRenderer wr) { return this; }
-		public void Render(WorldRenderer wr)
-		{
-			var map = wr.World.Map;
-			var r = map.Grid.Ramps[map.Ramp[pos]];
-			var wpos = map.CenterOfCell(pos) - new WVec(0, 0, r.CenterHeightOffset);
-
-			var corners = r.Corners.Select(corner => wr.Viewport.WorldToViewPx(wr.Screen3DPosition(wpos + corner))).ToList();
-
-			Game.Renderer.RgbaColorRenderer.FillRect(corners[0], corners[1], corners[2], corners[3], color);
-		}
-
-		public void RenderDebugGeometry(WorldRenderer wr) { }
-		public Rectangle ScreenBounds(WorldRenderer wr) { return Rectangle.Empty; }
-	}
-}

OpenRA.Game/Graphics/Model.cs

@@ -10,8 +10,9 @@
 #endregion
 
 using System;
+using System.Collections.Generic;
+using OpenRA.FileSystem;
 using OpenRA.Primitives;
-using OpenRA.Traits;
 
 namespace OpenRA.Graphics
 {
@@ -29,14 +30,6 @@ namespace OpenRA.Graphics
 		Rectangle AggregateBounds { get; }
 	}
 
-	public interface IModelWidget
-	{
-		public string Palette { get; }
-		public float Scale { get; }
-		public void Setup(Func<bool> isVisible, Func<string> getPalette, Func<string> getPlayerPalette,
-			Func<float> getScale, Func<IModel> getVoxel, Func<WRot> getRotation);
-	}
-
 	public readonly struct ModelRenderData
 	{
 		public readonly int Start;
@@ -51,13 +44,51 @@ namespace OpenRA.Graphics
 		}
 	}
 
-	public interface IModelCacheInfo : ITraitInfoInterface { }
-
-	public interface IModelCache
+	public interface IModelCache : IDisposable
 	{
 		IModel GetModel(string model);
 		IModel GetModelSequence(string model, string sequence);
 		bool HasModelSequence(string model, string sequence);
-		IVertexBuffer<ModelVertex> VertexBuffer { get; }
+		IVertexBuffer<Vertex> VertexBuffer { get; }
+	}
+
+	public interface IModelSequenceLoader
+	{
+		Action<string> OnMissingModelError { get; set; }
+		IModelCache CacheModels(IReadOnlyFileSystem fileSystem, ModData modData, IReadOnlyDictionary<string, MiniYamlNode> modelDefinitions);
+	}
+
+	public class PlaceholderModelSequenceLoader : IModelSequenceLoader
+	{
+		public Action<string> OnMissingModelError { get; set; }
+
+		sealed class PlaceholderModelCache : IModelCache
+		{
+			public IVertexBuffer<Vertex> VertexBuffer => throw new NotImplementedException();
+
+			public void Dispose() { }
+
+			public IModel GetModel(string model)
+			{
+				throw new NotImplementedException();
+			}
+
+			public IModel GetModelSequence(string model, string sequence)
+			{
+				throw new NotImplementedException();
+			}
+
+			public bool HasModelSequence(string model, string sequence)
+			{
+				throw new NotImplementedException();
+			}
+		}
+
+		public PlaceholderModelSequenceLoader(ModData modData) { }
+
+		public IModelCache CacheModels(IReadOnlyFileSystem fileSystem, ModData modData, IReadOnlyDictionary<string, MiniYamlNode> modelDefinitions)
+		{
+			return new PlaceholderModelCache();
+		}
 	}
 }

OpenRA.Game/Graphics/ModelRenderer.cs

@@ -12,11 +12,9 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using OpenRA.Graphics;
 using OpenRA.Primitives;
-using OpenRA.Traits;
 
-namespace OpenRA.Mods.Cnc.Traits
+namespace OpenRA.Graphics
 {
 	public class ModelRenderProxy
 	{
@@ -34,14 +32,7 @@ namespace OpenRA.Mods.Cnc.Traits
 		}
 	}
 
-	[TraitLocation(SystemActors.World | SystemActors.EditorWorld)]
-	[Desc("Render voxels")]
-	public class ModelRendererInfo : TraitInfo, Requires<IModelCacheInfo>
-	{
-		public override object Create(ActorInitializer init) { return new ModelRenderer(this, init.Self); }
-	}
-
-	public sealed class ModelRenderer : IDisposable, IRenderer, INotifyActorDisposing
+	public sealed class ModelRenderer : IDisposable
 	{
 		// Static constants
 		static readonly float[] ShadowDiffuse = new float[] { 0, 0, 0 };
@@ -55,32 +46,28 @@ namespace OpenRA.Mods.Cnc.Traits
 
 		readonly Renderer renderer;
 		readonly IShader shader;
-		public readonly IModelCache ModelCache;
 
 		readonly Dictionary<Sheet, IFrameBuffer> mappedBuffers = new();
 		readonly Stack<KeyValuePair<Sheet, IFrameBuffer>> unmappedBuffers = new();
 		readonly List<(Sheet Sheet, Action Func)> doRender = new();
-		readonly int sheetSize;
 
 		SheetBuilder sheetBuilderForFrame;
 		bool isInFrame;
 
-		public void SetPalette(HardwarePalette palette)
+		public ModelRenderer(Renderer renderer, IShader shader)
 		{
-			shader.SetTexture("Palette", palette.Texture);
-			shader.SetVec("PaletteRows", palette.Height);
+			this.renderer = renderer;
+			this.shader = shader;
 		}
 
-		public ModelRenderer(ModelRendererInfo info, Actor self)
+		public void SetPalette(ITexture palette)
 		{
-			renderer = Game.Renderer;
-			shader = renderer.CreateShader(new ModelShaderBindings());
-			renderer.WorldRenderers = renderer.WorldRenderers.Append(this).ToArray();
+			shader.SetTexture("Palette", palette);
+		}
 
-			ModelCache = self.Trait<IModelCache>();
-
-			sheetSize = Game.Settings.Graphics.SheetSize;
-			var a = 2f / sheetSize;
+		public void SetViewportParams()
+		{
+			var a = 2f / renderer.SheetSize;
 			var view = new[]
 			{
 				a, 0, 0, 0,
@@ -189,12 +176,12 @@ namespace OpenRA.Mods.Cnc.Traits
 			var spriteCenter = new float2(sb.Left + sb.Width / 2, sb.Top + sb.Height / 2);
 			var shadowCenter = new float2(ssb.Left + ssb.Width / 2, ssb.Top + ssb.Height / 2);
 
-			var translateMtx = Util.TranslationMatrix(spriteCenter.X - spriteOffset.X, sheetSize - (spriteCenter.Y - spriteOffset.Y), 0);
-			var shadowTranslateMtx = Util.TranslationMatrix(shadowCenter.X - shadowSpriteOffset.X, sheetSize - (shadowCenter.Y - shadowSpriteOffset.Y), 0);
+			var translateMtx = Util.TranslationMatrix(spriteCenter.X - spriteOffset.X, renderer.SheetSize - (spriteCenter.Y - spriteOffset.Y), 0);
+			var shadowTranslateMtx = Util.TranslationMatrix(shadowCenter.X - shadowSpriteOffset.X, renderer.SheetSize - (shadowCenter.Y - shadowSpriteOffset.Y), 0);
 			var correctionTransform = Util.MatrixMultiply(translateMtx, FlipMtx);
 			var shadowCorrectionTransform = Util.MatrixMultiply(shadowTranslateMtx, ShadowScaleFlipMtx);
 
-			void RenderFunc()
+			doRender.Add((sprite.Sheet, () =>
 			{
 				foreach (var m in models)
 				{
@@ -226,18 +213,16 @@ namespace OpenRA.Mods.Cnc.Traits
 						// Transform light vector from shadow -> world -> limb coords
 						var lightDirection = ExtractRotationVector(Util.MatrixMultiply(it, lightTransform));
 
-						Render(rd, ModelCache, Util.MatrixMultiply(transform, t), lightDirection,
-							lightAmbientColor, lightDiffuseColor, color.TextureIndex, normals.TextureIndex);
+						Render(rd, wr.World.ModelCache, Util.MatrixMultiply(transform, t), lightDirection,
+							lightAmbientColor, lightDiffuseColor, color.TextureMidIndex, normals.TextureMidIndex);
 
 						// Disable shadow normals by forcing zero diffuse and identity ambient light
 						if (m.ShowShadow)
-							Render(rd, ModelCache, Util.MatrixMultiply(shadow, t), lightDirection,
-								ShadowAmbient, ShadowDiffuse, shadowPalette.TextureIndex, normals.TextureIndex);
+							Render(rd, wr.World.ModelCache, Util.MatrixMultiply(shadow, t), lightDirection,
+								ShadowAmbient, ShadowDiffuse, shadowPalette.TextureMidIndex, normals.TextureMidIndex);
 					}
 				}
-			}
-
-			doRender.Add((sprite.Sheet, RenderFunc));
+			}));
 
 			var screenLightVector = Util.MatrixVectorMultiply(invShadowTransform, ZVector);
 			screenLightVector = Util.MatrixVectorMultiply(cameraTransform, screenLightVector);
@@ -252,9 +237,9 @@ namespace OpenRA.Mods.Cnc.Traits
 
 			// Width and height must be even to avoid rendering glitches
 			if ((width & 1) == 1)
-				width++;
+				width += 1;
 			if ((height & 1) == 1)
-				height++;
+				height += 1;
 
 			size = new Size(width, height);
 		}
@@ -282,17 +267,17 @@ namespace OpenRA.Mods.Cnc.Traits
 			IModelCache cache,
 			float[] t, float[] lightDirection,
 			float[] ambientLight, float[] diffuseLight,
-			float colorPaletteTextureIndex, float normalsPaletteTextureIndex)
+			float colorPaletteTextureMidIndex, float normalsPaletteTextureMidIndex)
 		{
 			shader.SetTexture("DiffuseTexture", renderData.Sheet.GetTexture());
-			shader.SetVec("Palettes", colorPaletteTextureIndex, normalsPaletteTextureIndex);
+			shader.SetVec("PaletteRows", colorPaletteTextureMidIndex, normalsPaletteTextureMidIndex);
 			shader.SetMatrix("TransformMatrix", t);
 			shader.SetVec("LightDirection", lightDirection, 4);
 			shader.SetVec("AmbientLight", ambientLight, 3);
 			shader.SetVec("DiffuseLight", diffuseLight, 3);
 
 			shader.PrepareRender();
-			renderer.DrawBatch(cache.VertexBuffer, shader, renderData.Start, renderData.Count, PrimitiveType.TriangleList);
+			renderer.DrawBatch(cache.VertexBuffer, renderData.Start, renderData.Count, PrimitiveType.TriangleList);
 		}
 
 		public void BeginFrame()
@@ -313,14 +298,14 @@ namespace OpenRA.Mods.Cnc.Traits
 			Game.Renderer.Flush();
 			fbo.Bind();
 
-			Game.Renderer.EnableDepthBuffer();
+			Game.Renderer.Context.EnableDepthBuffer();
 			return fbo;
 		}
 
 		static void DisableFrameBuffer(IFrameBuffer fbo)
 		{
 			Game.Renderer.Flush();
-			Game.Renderer.DisableDepthBuffer();
+			Game.Renderer.Context.DisableDepthBuffer();
 			fbo.Unbind();
 		}
 
@@ -368,7 +353,8 @@ namespace OpenRA.Mods.Cnc.Traits
 				return kv.Key;
 			}
 
-			var framebuffer = renderer.CreateFrameBuffer(new Size(sheetSize, sheetSize));
+			var size = new Size(renderer.SheetSize, renderer.SheetSize);
+			var framebuffer = renderer.Context.CreateFrameBuffer(size);
 			var sheet = new Sheet(SheetType.BGRA, framebuffer.Texture);
 			mappedBuffers.Add(sheet, framebuffer);
 
@@ -385,12 +371,6 @@ namespace OpenRA.Mods.Cnc.Traits
 
 			mappedBuffers.Clear();
 			unmappedBuffers.Clear();
-			renderer.WorldRenderers = renderer.WorldRenderers.Where(r => r != this).ToArray();
-		}
-
-		void INotifyActorDisposing.Disposing(Actor a)
-		{
-			Dispose();
 		}
 	}
 }

OpenRA.Game/Graphics/ModelVertex.cs

@@ -1,53 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.Runtime.InteropServices;
-
-namespace OpenRA.Graphics
-{
-	[StructLayout(LayoutKind.Sequential)]
-	public readonly struct ModelVertex
-	{
-		// 3d position
-		public readonly float X, Y, Z;
-
-		// Primary and secondary texture coordinates or RGBA color
-		public readonly float S, T, U, V;
-
-		// Palette and channel flags
-		public readonly float P, C;
-
-		public ModelVertex(in float3 xyz, float s, float t, float u, float v, float p, float c)
-			: this(xyz.X, xyz.Y, xyz.Z, s, t, u, v, p, c) { }
-
-		public ModelVertex(float x, float y, float z, float s, float t, float u, float v, float p, float c)
-		{
-			X = x; Y = y; Z = z;
-			S = s; T = t;
-			U = u; V = v;
-			P = p; C = c;
-		}
-	}
-
-	public sealed class ModelShaderBindings : ShaderBindings
-	{
-		public ModelShaderBindings()
-			: base("model")
-		{ }
-
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
-			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 3, 0),
-			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 4, 12),
-			new ShaderVertexAttribute("aVertexTexMetadata", ShaderVertexAttributeType.Float, 2, 28),
-		};
-	}
-}

OpenRA.Game/Graphics/Palette.cs

@@ -30,7 +30,7 @@ namespace OpenRA.Graphics
 
 		public static Color GetColor(this IPalette palette, int index)
 		{
-			return Color.FromArgb(palette[index]);
+			return Color.FromArgb((int)palette[index]);
 		}
 
 		public static IPalette AsReadOnly(this IPalette palette)
@@ -103,7 +103,7 @@ namespace OpenRA.Graphics
 			: this(p)
 		{
 			for (var i = 0; i < Palette.Size; i++)
-				colors[i] = r.GetRemappedColor(this.GetColor(i), i).ToArgb();
+				colors[i] = (uint)r.GetRemappedColor(this.GetColor(i), i).ToArgb();
 		}
 
 		public ImmutablePalette(IPalette p)
@@ -142,7 +142,7 @@ namespace OpenRA.Graphics
 
 		public void SetColor(int index, Color color)
 		{
-			colors[index] = color.ToArgb();
+			colors[index] = (uint)color.ToArgb();
 		}
 
 		public void SetFromPalette(IPalette p)
@@ -153,7 +153,7 @@ namespace OpenRA.Graphics
 		public void ApplyRemap(IPaletteRemap r)
 		{
 			for (var i = 0; i < Palette.Size; i++)
-				colors[i] = r.GetRemappedColor(this.GetColor(i), i).ToArgb();
+				colors[i] = (uint)r.GetRemappedColor(this.GetColor(i), i).ToArgb();
 		}
 	}
 }

OpenRA.Game/Graphics/PaletteReference.cs

@@ -13,17 +13,19 @@ namespace OpenRA.Graphics
 {
 	public sealed class PaletteReference
 	{
+		readonly float index;
 		readonly HardwarePalette hardwarePalette;
 
 		public readonly string Name;
 		public IPalette Palette { get; internal set; }
-		public int TextureIndex { get; }
+		public float TextureIndex => index / hardwarePalette.Height;
+		public float TextureMidIndex => (index + 0.5f) / hardwarePalette.Height;
 
 		public PaletteReference(string name, int index, IPalette palette, HardwarePalette hardwarePalette)
 		{
 			Name = name;
 			Palette = palette;
-			TextureIndex = index;
+			this.index = index;
 			this.hardwarePalette = hardwarePalette;
 		}
 

OpenRA.Game/Graphics/PlatformInterfaces.cs

@@ -20,12 +20,13 @@ namespace OpenRA
 		Automatic,
 		ANGLE,
 		Modern,
-		Embedded
+		Embedded,
+		Legacy
 	}
 
 	public interface IPlatform
 	{
-		IPlatformWindow CreateWindow(Size size, WindowMode windowMode, float scaleModifier, int vertexBatchSize, int indexBatchSize, int videoDisplay, GLProfile profile);
+		IPlatformWindow CreateWindow(Size size, WindowMode windowMode, float scaleModifier, int batchSize, int videoDisplay, GLProfile profile, bool enableLegacyGL);
 		ISoundEngine CreateSound(string device);
 		IFont CreateFont(byte[] data);
 	}
@@ -82,18 +83,16 @@ namespace OpenRA
 
 	public interface IGraphicsContext : IDisposable
 	{
-		IVertexBuffer<T> CreateVertexBuffer<T>(int size) where T : struct;
-		T[] CreateVertices<T>(int size) where T : struct;
-		IIndexBuffer CreateIndexBuffer(uint[] indices);
+		IVertexBuffer<Vertex> CreateVertexBuffer(int size);
+		Vertex[] CreateVertices(int size);
 		ITexture CreateTexture();
 		IFrameBuffer CreateFrameBuffer(Size s);
 		IFrameBuffer CreateFrameBuffer(Size s, Color clearColor);
-		IShader CreateShader(IShaderBindings shaderBindings);
+		IShader CreateShader(string name);
 		void EnableScissor(int x, int y, int width, int height);
 		void DisableScissor();
 		void Present();
 		void DrawPrimitives(PrimitiveType pt, int firstVertex, int numVertices);
-		void DrawElements(int numIndices, int offset);
 		void Clear();
 		void EnableDepthBuffer();
 		void DisableDepthBuffer();
@@ -103,14 +102,7 @@ namespace OpenRA
 		string GLVersion { get; }
 	}
 
-	public interface IRenderer
-	{
-		void BeginFrame();
-		void EndFrame();
-		void SetPalette(HardwarePalette palette);
-	}
-
-	public interface IVertexBuffer<T> : IDisposable where T : struct
+	public interface IVertexBuffer<T> : IDisposable
 	{
 		void Bind();
 		void SetData(T[] vertices, int length);
@@ -122,11 +114,6 @@ namespace OpenRA
 		void SetData(T[] vertices, int offset, int start, int length);
 	}
 
-	public interface IIndexBuffer : IDisposable
-	{
-		void Bind();
-	}
-
 	public interface IShader
 	{
 		void SetBool(string name, bool value);
@@ -137,17 +124,6 @@ namespace OpenRA
 		void SetTexture(string param, ITexture texture);
 		void SetMatrix(string param, float[] mtx);
 		void PrepareRender();
-		void Bind();
-	}
-
-	public interface IShaderBindings
-	{
-		string VertexShaderName { get; }
-		string VertexShaderCode { get; }
-		string FragmentShaderName { get; }
-		string FragmentShaderCode { get; }
-		int Stride { get; }
-		ShaderVertexAttribute[] Attributes { get; }
 	}
 
 	public enum TextureScaleFilter { Nearest, Linear }
@@ -156,7 +132,6 @@ namespace OpenRA
 	{
 		void SetData(byte[] colors, int width, int height);
 		void SetFloatData(float[] data, int width, int height);
-		void SetDataFromReadBuffer(Rectangle rect);
 		byte[] GetData();
 		Size Size { get; }
 		TextureScaleFilter ScaleFilter { get; set; }

OpenRA.Game/Graphics/RenderPostProcessPassVertex.cs

@@ -1,64 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.Runtime.InteropServices;
-
-namespace OpenRA.Graphics
-{
-	[StructLayout(LayoutKind.Sequential)]
-	public readonly struct RenderPostProcessPassVertex
-	{
-		public readonly float X, Y;
-
-		public RenderPostProcessPassVertex(float x, float y)
-		{
-			X = x; Y = y;
-		}
-	}
-
-	[StructLayout(LayoutKind.Sequential)]
-	public readonly struct RenderPostProcessPassTexturedVertex
-	{
-		// 3d position
-		public readonly float X, Y;
-		public readonly float S, T;
-
-		public RenderPostProcessPassTexturedVertex(float x, float y, float s, float t)
-		{
-			X = x; Y = y;
-			S = s; T = t;
-		}
-	}
-
-	public sealed class RenderPostProcessPassShaderBindings : ShaderBindings
-	{
-		public RenderPostProcessPassShaderBindings(string name)
-			: base("postprocess", "postprocess_" + name) { }
-
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
-			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 2, 0)
-		};
-	}
-
-	public sealed class RenderPostProcessPassTexturedShaderBindings : ShaderBindings
-	{
-		public RenderPostProcessPassTexturedShaderBindings(string name)
-			: base("postprocess_textured", "postprocess_textured_" + name)
-		{ }
-
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
-			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 2, 0),
-			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 2, 8),
-		};
-	}
-}

OpenRA.Game/Graphics/RgbaColorRenderer.cs

@@ -21,7 +21,7 @@ namespace OpenRA.Graphics
 		static readonly float3 Offset = new(0.5f, 0.5f, 0f);
 
 		readonly SpriteRenderer parent;
-		readonly Vertex[] vertices = new Vertex[4];
+		readonly Vertex[] vertices = new Vertex[6];
 
 		public RgbaColorRenderer(SpriteRenderer parent)
 		{
@@ -45,12 +45,14 @@ namespace OpenRA.Graphics
 			var eb = endColor.B / 255.0f;
 			var ea = endColor.A / 255.0f;
 
-			vertices[0] = new Vertex(start - corner + Offset, sr, sg, sb, sa, 0);
-			vertices[1] = new Vertex(start + corner + Offset, sr, sg, sb, sa, 0);
-			vertices[2] = new Vertex(end + corner + Offset, er, eg, eb, ea, 0);
-			vertices[3] = new Vertex(end - corner + Offset, er, eg, eb, ea, 0);
+			vertices[0] = new Vertex(start - corner + Offset, sr, sg, sb, sa, 0, 0);
+			vertices[1] = new Vertex(start + corner + Offset, sr, sg, sb, sa, 0, 0);
+			vertices[2] = new Vertex(end + corner + Offset, er, eg, eb, ea, 0, 0);
+			vertices[3] = new Vertex(end + corner + Offset, er, eg, eb, ea, 0, 0);
+			vertices[4] = new Vertex(end - corner + Offset, er, eg, eb, ea, 0, 0);
+			vertices[5] = new Vertex(start - corner + Offset, sr, sg, sb, sa, 0, 0);
 
-			parent.DrawRGBAQuad(vertices, blendMode);
+			parent.DrawRGBAVertices(vertices, blendMode);
 		}
 
 		public void DrawLine(in float3 start, in float3 end, float width, Color color, BlendMode blendMode = BlendMode.Alpha)
@@ -64,11 +66,13 @@ namespace OpenRA.Graphics
 			var b = color.B / 255.0f;
 			var a = color.A / 255.0f;
 
-			vertices[0] = new Vertex(start - corner + Offset, r, g, b, a, 0);
-			vertices[1] = new Vertex(start + corner + Offset, r, g, b, a, 0);
-			vertices[2] = new Vertex(end + corner + Offset, r, g, b, a, 0);
-			vertices[3] = new Vertex(end - corner + Offset, r, g, b, a, 0);
-			parent.DrawRGBAQuad(vertices, blendMode);
+			vertices[0] = new Vertex(start - corner + Offset, r, g, b, a, 0, 0);
+			vertices[1] = new Vertex(start + corner + Offset, r, g, b, a, 0, 0);
+			vertices[2] = new Vertex(end + corner + Offset, r, g, b, a, 0, 0);
+			vertices[3] = new Vertex(end + corner + Offset, r, g, b, a, 0, 0);
+			vertices[4] = new Vertex(end - corner + Offset, r, g, b, a, 0, 0);
+			vertices[5] = new Vertex(start - corner + Offset, r, g, b, a, 0, 0);
+			parent.DrawRGBAVertices(vertices, blendMode);
 		}
 
 		/// <summary>
@@ -153,11 +157,13 @@ namespace OpenRA.Graphics
 				var cd = closed || i < limit - 1 ? IntersectionOf(end - corner, dir, end - nextCorner, nextDir) : end - corner;
 
 				// Fill segment
-				vertices[0] = new Vertex(ca + Offset, r, g, b, a, 0);
-				vertices[1] = new Vertex(cb + Offset, r, g, b, a, 0);
-				vertices[2] = new Vertex(cc + Offset, r, g, b, a, 0);
-				vertices[3] = new Vertex(cd + Offset, r, g, b, a, 0);
-				parent.DrawRGBAQuad(vertices, blendMode);
+				vertices[0] = new Vertex(ca + Offset, r, g, b, a, 0, 0);
+				vertices[1] = new Vertex(cb + Offset, r, g, b, a, 0, 0);
+				vertices[2] = new Vertex(cc + Offset, r, g, b, a, 0, 0);
+				vertices[3] = new Vertex(cc + Offset, r, g, b, a, 0, 0);
+				vertices[4] = new Vertex(cd + Offset, r, g, b, a, 0, 0);
+				vertices[5] = new Vertex(ca + Offset, r, g, b, a, 0, 0);
+				parent.DrawRGBAVertices(vertices, blendMode);
 
 				// Advance line segment
 				end = next;
@@ -194,6 +200,20 @@ namespace OpenRA.Graphics
 			DrawPolygon(new[] { tl, tr, br, bl }, width, color, blendMode);
 		}
 
+		public void FillTriangle(in float3 a, in float3 b, in float3 c, Color color, BlendMode blendMode = BlendMode.Alpha)
+		{
+			color = Util.PremultiplyAlpha(color);
+			var cr = color.R / 255.0f;
+			var cg = color.G / 255.0f;
+			var cb = color.B / 255.0f;
+			var ca = color.A / 255.0f;
+
+			vertices[0] = new Vertex(a + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[1] = new Vertex(b + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[2] = new Vertex(c + Offset, cr, cg, cb, ca, 0, 0);
+			parent.DrawRGBAVertices(vertices, blendMode);
+		}
+
 		public void FillRect(in float3 tl, in float3 br, Color color, BlendMode blendMode = BlendMode.Alpha)
 		{
 			var tr = new float3(br.X, tl.Y, tl.Z);
@@ -209,11 +229,13 @@ namespace OpenRA.Graphics
 			var cb = color.B / 255.0f;
 			var ca = color.A / 255.0f;
 
-			vertices[0] = new Vertex(a + Offset, cr, cg, cb, ca, 0);
-			vertices[1] = new Vertex(b + Offset, cr, cg, cb, ca, 0);
-			vertices[2] = new Vertex(c + Offset, cr, cg, cb, ca, 0);
-			vertices[3] = new Vertex(d + Offset, cr, cg, cb, ca, 0);
-			parent.DrawRGBAQuad(vertices, blendMode);
+			vertices[0] = new Vertex(a + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[1] = new Vertex(b + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[2] = new Vertex(c + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[3] = new Vertex(c + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[4] = new Vertex(d + Offset, cr, cg, cb, ca, 0, 0);
+			vertices[5] = new Vertex(a + Offset, cr, cg, cb, ca, 0, 0);
+			parent.DrawRGBAVertices(vertices, blendMode);
 		}
 
 		public void FillRect(in float3 a, in float3 b, in float3 c, in float3 d, Color topLeftColor, Color topRightColor, Color bottomRightColor, Color bottomLeftColor, BlendMode blendMode = BlendMode.Alpha)
@@ -221,9 +243,11 @@ namespace OpenRA.Graphics
 			vertices[0] = VertexWithColor(a + Offset, topLeftColor);
 			vertices[1] = VertexWithColor(b + Offset, topRightColor);
 			vertices[2] = VertexWithColor(c + Offset, bottomRightColor);
-			vertices[3] = VertexWithColor(d + Offset, bottomLeftColor);
+			vertices[3] = VertexWithColor(c + Offset, bottomRightColor);
+			vertices[4] = VertexWithColor(d + Offset, bottomLeftColor);
+			vertices[5] = VertexWithColor(a + Offset, topLeftColor);
 
-			parent.DrawRGBAQuad(vertices, blendMode);
+			parent.DrawRGBAVertices(vertices, blendMode);
 		}
 
 		static Vertex VertexWithColor(in float3 xyz, Color color)
@@ -234,7 +258,7 @@ namespace OpenRA.Graphics
 			var cb = color.B / 255.0f;
 			var ca = color.A / 255.0f;
 
-			return new Vertex(xyz, cr, cg, cb, ca, 0);
+			return new Vertex(xyz, cr, cg, cb, ca, 0, 0);
 		}
 
 		public void FillEllipse(in float3 tl, in float3 br, Color color, BlendMode blendMode = BlendMode.Alpha)

OpenRA.Game/Graphics/SequenceSet.cs

@@ -94,7 +94,7 @@ namespace OpenRA.Graphics
 			foreach (var node in nodes)
 			{
 				// Nodes starting with ^ are inheritable but never loaded directly
-				if (node.Key.StartsWith(ActorInfo.AbstractActorPrefix))
+				if (node.Key.StartsWith(ActorInfo.AbstractActorPrefix, StringComparison.Ordinal))
 					continue;
 
 				images[node.Key] = modData.SpriteSequenceLoader.ParseSequences(modData, tileSet, SpriteCache, node);

OpenRA.Game/Graphics/ShaderBindings.cs

@@ -1,70 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.IO;
-using System.Linq;
-
-namespace OpenRA.Graphics
-{
-	public enum ShaderVertexAttributeType
-	{
-		// Assign the underlying OpenGL type values
-		// to simplify enum use in the shader
-		Float = 0x1406, // GL_FLOAT
-		Int = 0x1404, // GL_INT
-		UInt = 0x1405 // GL_UNSIGNED_INT
-	}
-
-	public readonly struct ShaderVertexAttribute
-	{
-		public readonly string Name;
-		public readonly ShaderVertexAttributeType Type;
-		public readonly int Components;
-		public readonly int Offset;
-
-		public ShaderVertexAttribute(string name, ShaderVertexAttributeType type, int components, int offset)
-		{
-			Name = name;
-			Type = type;
-			Components = components;
-			Offset = offset;
-		}
-	}
-
-	public abstract class ShaderBindings : IShaderBindings
-	{
-		public string VertexShaderName { get; }
-		public string VertexShaderCode { get; }
-		public string FragmentShaderName { get; }
-		public string FragmentShaderCode { get; }
-		public int Stride { get; }
-
-		public abstract ShaderVertexAttribute[] Attributes { get; }
-
-		protected ShaderBindings(string name)
-			: this(name, name) { }
-
-		protected ShaderBindings(string vertexName, string fragmentName)
-		{
-			Stride = Attributes.Sum(a => a.Components * 4);
-			VertexShaderName = vertexName;
-			VertexShaderCode = GetShaderCode(VertexShaderName + ".vert");
-			FragmentShaderName = fragmentName;
-			FragmentShaderCode = GetShaderCode(FragmentShaderName + ".frag");
-		}
-
-		public static string GetShaderCode(string filename)
-		{
-			var filepath = Path.Combine(Platform.EngineDir, "glsl", filename);
-			return File.ReadAllText(filepath);
-		}
-	}
-}

OpenRA.Game/Graphics/SheetBuilder.cs

@@ -82,16 +82,16 @@ namespace OpenRA.Graphics
 			this.margin = margin;
 		}
 
-		public Sprite Add(ISpriteFrame frame, bool premultiplied = false) { return Add(frame.Data, frame.Type, frame.Size, 0, frame.Offset, premultiplied); }
-		public Sprite Add(byte[] src, SpriteFrameType type, Size size, bool premultiplied = false) { return Add(src, type, size, 0, float3.Zero, premultiplied); }
-		public Sprite Add(byte[] src, SpriteFrameType type, Size size, float zRamp, in float3 spriteOffset, bool premultiplied = false)
+		public Sprite Add(ISpriteFrame frame) { return Add(frame.Data, frame.Type, frame.Size, 0, frame.Offset); }
+		public Sprite Add(byte[] src, SpriteFrameType type, Size size) { return Add(src, type, size, 0, float3.Zero); }
+		public Sprite Add(byte[] src, SpriteFrameType type, Size size, float zRamp, in float3 spriteOffset)
 		{
 			// Don't bother allocating empty sprites
 			if (size.Width == 0 || size.Height == 0)
 				return new Sprite(Current, Rectangle.Empty, 0, spriteOffset, CurrentChannel, BlendMode.Alpha);
 
 			var rect = Allocate(size, zRamp, spriteOffset);
-			Util.FastCopyIntoChannel(rect, src, type, premultiplied);
+			Util.FastCopyIntoChannel(rect, src, type);
 			Current.CommitBufferedData();
 			return rect;
 		}

OpenRA.Game/Graphics/Sprite.cs

@@ -42,11 +42,11 @@ namespace OpenRA.Graphics
 			// in rendering a line of texels that sample outside the sprite rectangle.
 			// Insetting the texture coordinates by a small fraction of a pixel avoids this
 			// with negligible impact on the 1:1 rendering case.
-			const float Inset = 1 / 128f;
-			Left = (Math.Min(bounds.Left, bounds.Right) + Inset) / sheet.Size.Width;
-			Top = (Math.Min(bounds.Top, bounds.Bottom) + Inset) / sheet.Size.Height;
-			Right = (Math.Max(bounds.Left, bounds.Right) - Inset) / sheet.Size.Width;
-			Bottom = (Math.Max(bounds.Top, bounds.Bottom) - Inset) / sheet.Size.Height;
+			var inset = 1 / 128f;
+			Left = (Math.Min(bounds.Left, bounds.Right) + inset) / sheet.Size.Width;
+			Top = (Math.Min(bounds.Top, bounds.Bottom) + inset) / sheet.Size.Height;
+			Right = (Math.Max(bounds.Left, bounds.Right) - inset) / sheet.Size.Width;
+			Bottom = (Math.Max(bounds.Top, bounds.Bottom) - inset) / sheet.Size.Height;
 		}
 	}
 

OpenRA.Game/Graphics/SpriteCache.cs

@@ -24,9 +24,11 @@ namespace OpenRA.Graphics
 		readonly ISpriteLoader[] loaders;
 		readonly IReadOnlyFileSystem fileSystem;
 
-		readonly Dictionary<int, (int[] Frames, MiniYamlNode.SourceLocation Location, Func<ISpriteFrame, ISpriteFrame> AdjustFrame, bool Premultiplied)> spriteReservations = new();
+		readonly Dictionary<int, (int[] Frames, MiniYamlNode.SourceLocation Location)> spriteReservations = new();
+		readonly Dictionary<int, (int[] Frames, MiniYamlNode.SourceLocation Location)> frameReservations = new();
 		readonly Dictionary<string, List<int>> reservationsByFilename = new();
 
+		readonly Dictionary<int, ISpriteFrame[]> resolvedFrames = new();
 		readonly Dictionary<int, Sprite[]> resolvedSprites = new();
 
 		readonly Dictionary<int, (string Filename, MiniYamlNode.SourceLocation Location)> missingFiles = new();
@@ -45,10 +47,18 @@ namespace OpenRA.Graphics
 			this.loaders = loaders;
 		}
 
-		public int ReserveSprites(string filename, IEnumerable<int> frames, MiniYamlNode.SourceLocation location, Func<ISpriteFrame, ISpriteFrame> adjustFrame = null, bool premultiplied = false)
+		public int ReserveSprites(string filename, IEnumerable<int> frames, MiniYamlNode.SourceLocation location)
 		{
 			var token = nextReservationToken++;
-			spriteReservations[token] = (frames?.ToArray(), location, adjustFrame, premultiplied);
+			spriteReservations[token] = (frames?.ToArray(), location);
+			reservationsByFilename.GetOrAdd(filename, _ => new List<int>()).Add(token);
+			return token;
+		}
+
+		public int ReserveFrames(string filename, IEnumerable<int> frames, MiniYamlNode.SourceLocation location)
+		{
+			var token = nextReservationToken++;
+			frameReservations[token] = (frames?.ToArray(), location);
 			reservationsByFilename.GetOrAdd(filename, _ => new List<int>()).Add(token);
 			return token;
 		}
@@ -74,73 +84,60 @@ namespace OpenRA.Graphics
 			foreach (var sb in SheetBuilders.Values)
 				sb.Current.CreateBuffer();
 
-			var pendingResolve = new List<(
-				string Filename,
-				int FrameIndex,
-				bool Premultiplied,
-				Func<ISpriteFrame, ISpriteFrame> AdjustFrame,
-				ISpriteFrame Frame,
-				Sprite[] SpritesForToken)>();
+			var spriteCache = new Dictionary<int, Sprite>();
 			foreach (var (filename, tokens) in reservationsByFilename)
 			{
 				modData.LoadScreen?.Display();
 				var loadedFrames = GetFrames(fileSystem, filename, loaders, out _);
 				foreach (var token in tokens)
 				{
-					if (spriteReservations.TryGetValue(token, out var rs))
+					if (frameReservations.TryGetValue(token, out var r))
+					{
+						if (loadedFrames != null)
+						{
+							if (r.Frames != null)
+							{
+								var resolved = new ISpriteFrame[loadedFrames.Length];
+								foreach (var i in r.Frames)
+									resolved[i] = loadedFrames[i];
+								resolvedFrames[token] = resolved;
+							}
+							else
+								resolvedFrames[token] = loadedFrames;
+						}
+						else
+						{
+							resolvedFrames[token] = null;
+							missingFiles[token] = (filename, r.Location);
+						}
+					}
+
+					if (spriteReservations.TryGetValue(token, out r))
 					{
 						if (loadedFrames != null)
 						{
 							var resolved = new Sprite[loadedFrames.Length];
-							resolvedSprites[token] = resolved;
-							var frames = rs.Frames ?? Enumerable.Range(0, loadedFrames.Length);
-
+							var frames = r.Frames ?? Enumerable.Range(0, loadedFrames.Length);
 							foreach (var i in frames)
-							{
-								var frame = loadedFrames[i];
-								if (rs.AdjustFrame != null)
-									frame = rs.AdjustFrame(frame);
-								pendingResolve.Add((filename, i, rs.Premultiplied, rs.AdjustFrame, frame, resolved));
-							}
+								resolved[i] = spriteCache.GetOrAdd(i,
+									f => SheetBuilders[SheetBuilder.FrameTypeToSheetType(loadedFrames[f].Type)].Add(loadedFrames[f]));
+
+							resolvedSprites[token] = resolved;
 						}
 						else
 						{
 							resolvedSprites[token] = null;
-							missingFiles[token] = (filename, rs.Location);
+							missingFiles[token] = (filename, r.Location);
 						}
 					}
 				}
+
+				spriteCache.Clear();
 			}
 
 			spriteReservations.Clear();
-			spriteReservations.TrimExcess();
+			frameReservations.Clear();
 			reservationsByFilename.Clear();
-			reservationsByFilename.TrimExcess();
-
-			// When the sheet builder is adding sprites, it reserves height for the tallest sprite seen along the row.
-			// We can achieve better sheet packing by keeping sprites with similar heights together.
-			var orderedPendingResolve = pendingResolve.OrderBy(x => x.Frame.Size.Height);
-
-			var spriteCache = new Dictionary<(
-				string Filename,
-				int FrameIndex,
-				bool Premultiplied,
-				Func<ISpriteFrame, ISpriteFrame> AdjustFrame),
-				Sprite>(pendingResolve.Count);
-			foreach (var (filename, frameIndex, premultiplied, adjustFrame, frame, spritesForToken) in orderedPendingResolve)
-			{
-				// Premultiplied and non-premultiplied sprites must be cached separately
-				// to cover the case where the same image is requested in both versions.
-				spritesForToken[frameIndex] = spriteCache.GetOrAdd(
-					(filename, frameIndex, premultiplied, adjustFrame),
-					_ =>
-					{
-						var sheetBuilder = SheetBuilders[SheetBuilder.FrameTypeToSheetType(frame.Type)];
-						return sheetBuilder.Add(frame, premultiplied);
-					});
-
-				modData.LoadScreen?.Display();
-			}
 
 			foreach (var sb in SheetBuilders.Values)
 				sb.Current.ReleaseBuffer();
@@ -148,11 +145,18 @@ namespace OpenRA.Graphics
 
 		public Sprite[] ResolveSprites(int token)
 		{
-			if (!resolvedSprites.Remove(token, out var resolved))
-				throw new InvalidOperationException($"{nameof(token)} {token} has either already been resolved, or was never reserved via {nameof(ReserveSprites)}");
+			var resolved = resolvedSprites[token];
+			resolvedSprites.Remove(token);
+			if (missingFiles.TryGetValue(token, out var r))
+				throw new FileNotFoundException($"{r.Location}: {r.Filename} not found", r.Filename);
 
-			resolvedSprites.TrimExcess();
+			return resolved;
+		}
 
+		public ISpriteFrame[] ResolveFrames(int token)
+		{
+			var resolved = resolvedFrames[token];
+			resolvedFrames.Remove(token);
 			if (missingFiles.TryGetValue(token, out var r))
 				throw new FileNotFoundException($"{r.Location}: {r.Filename} not found", r.Filename);
 

OpenRA.Game/Graphics/SpriteLoader.cs

@@ -22,30 +22,20 @@ namespace OpenRA.Graphics
 	/// </summary>
 	public enum SpriteFrameType
 	{
-		/// <summary>
-		/// 8 bit index into an external palette.
-		/// </summary>
+		// 8 bit index into an external palette
 		Indexed8,
 
-		/// <summary>
-		/// 32 bit color such as returned by Color.ToArgb() or the bmp file format
-		/// (remember that little-endian systems place the little bits in the first byte).
-		/// </summary>
+		// 32 bit color such as returned by Color.ToArgb() or the bmp file format
+		// (remember that little-endian systems place the little bits in the first byte!)
 		Bgra32,
 
-		/// <summary>
-		/// Like BGRA, but without an alpha channel.
-		/// </summary>
+		// Like BGRA, but without an alpha channel
 		Bgr24,
 
-		/// <summary>
-		/// 32 bit color in big-endian format, like png.
-		/// </summary>
+		// 32 bit color in big-endian format, like png
 		Rgba32,
 
-		/// <summary>
-		/// Like RGBA, but without an alpha channel.
-		/// </summary>
+		// Like RGBA, but without an alpha channel
 		Rgb24
 	}
 

OpenRA.Game/Graphics/SpriteRenderer.cs

@@ -11,7 +11,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Runtime.InteropServices;
 using OpenRA.Primitives;
 
 namespace OpenRA.Graphics
@@ -20,7 +19,6 @@ namespace OpenRA.Graphics
 	{
 		public const int SheetCount = 8;
 		static readonly string[] SheetIndexToTextureName = Exts.MakeArray(SheetCount, i => $"Texture{i}");
-		static readonly int UintSize = Marshal.SizeOf(typeof(uint));
 
 		readonly Renderer renderer;
 		readonly IShader shader;
@@ -29,21 +27,21 @@ namespace OpenRA.Graphics
 		readonly Sheet[] sheets = new Sheet[SheetCount];
 
 		BlendMode currentBlend = BlendMode.Alpha;
-		int vertexCount = 0;
-		int sheetCount = 0;
+		int nv = 0;
+		int ns = 0;
 
 		public SpriteRenderer(Renderer renderer, IShader shader)
 		{
 			this.renderer = renderer;
 			this.shader = shader;
-			vertices = renderer.Context.CreateVertices<Vertex>(renderer.TempVertexBufferSize);
+			vertices = renderer.Context.CreateVertices(renderer.TempBufferSize);
 		}
 
 		public void Flush()
 		{
-			if (vertexCount > 0)
+			if (nv > 0)
 			{
-				for (var i = 0; i < sheetCount; i++)
+				for (var i = 0; i < ns; i++)
 				{
 					shader.SetTexture(SheetIndexToTextureName[i], sheets[i].GetTexture());
 					sheets[i] = null;
@@ -52,11 +50,12 @@ namespace OpenRA.Graphics
 				renderer.Context.SetBlendMode(currentBlend);
 				shader.PrepareRender();
 
-				renderer.DrawQuadBatch(ref vertices, shader, vertexCount);
+				// PERF: The renderer may choose to replace vertices with a different temporary buffer.
+				renderer.DrawBatch(ref vertices, nv, PrimitiveType.TriangleList);
 				renderer.Context.SetBlendMode(BlendMode.None);
 
-				vertexCount = 0;
-				sheetCount = 0;
+				nv = 0;
+				ns = 0;
 			}
 		}
 
@@ -64,7 +63,7 @@ namespace OpenRA.Graphics
 		{
 			renderer.CurrentBatchRenderer = this;
 
-			if (s.BlendMode != currentBlend || vertexCount + 4 > renderer.TempVertexBufferSize)
+			if (s.BlendMode != currentBlend || nv + 6 > renderer.TempBufferSize)
 				Flush();
 
 			currentBlend = s.BlendMode;
@@ -72,7 +71,7 @@ namespace OpenRA.Graphics
 			// Check if the sheet (or secondary data sheet) have already been mapped
 			var sheet = s.Sheet;
 			var sheetIndex = 0;
-			for (; sheetIndex < sheetCount; sheetIndex++)
+			for (; sheetIndex < ns; sheetIndex++)
 				if (sheets[sheetIndex] == sheet)
 					break;
 
@@ -81,7 +80,7 @@ namespace OpenRA.Graphics
 			if (ss != null)
 			{
 				var secondarySheet = ss.SecondarySheet;
-				for (; secondarySheetIndex < sheetCount; secondarySheetIndex++)
+				for (; secondarySheetIndex < ns; secondarySheetIndex++)
 					if (sheets[secondarySheetIndex] == secondarySheet)
 						break;
 
@@ -100,22 +99,22 @@ namespace OpenRA.Graphics
 				secondarySheetIndex = ss != null && ss.SecondarySheet != sheet ? 1 : 0;
 			}
 
-			if (sheetIndex >= sheetCount)
+			if (sheetIndex >= ns)
 			{
 				sheets[sheetIndex] = sheet;
-				sheetCount++;
+				ns++;
 			}
 
-			if (secondarySheetIndex >= sheetCount && ss != null)
+			if (secondarySheetIndex >= ns && ss != null)
 			{
 				sheets[secondarySheetIndex] = ss.SecondarySheet;
-				sheetCount++;
+				ns++;
 			}
 
 			return new int2(sheetIndex, secondarySheetIndex);
 		}
 
-		static int ResolveTextureIndex(Sprite s, PaletteReference pal)
+		static float ResolveTextureIndex(Sprite s, PaletteReference pal)
 		{
 			if (pal == null)
 				return 0;
@@ -129,20 +128,20 @@ namespace OpenRA.Graphics
 			return pal.TextureIndex;
 		}
 
-		internal void DrawSprite(Sprite s, int paletteTextureIndex, in float3 location, in float3 scale, float rotation = 0f)
+		internal void DrawSprite(Sprite s, float paletteTextureIndex, in float3 location, in float3 scale, float rotation = 0f)
 		{
 			var samplers = SetRenderStateForSprite(s);
-			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, vertexCount, scale * s.Size, float3.Ones,
+			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, nv, scale * s.Size, float3.Ones,
 								1f, rotation);
-			vertexCount += 4;
+			nv += 6;
 		}
 
-		internal void DrawSprite(Sprite s, int paletteTextureIndex, in float3 location, float scale, float rotation = 0f)
+		internal void DrawSprite(Sprite s, float paletteTextureIndex, in float3 location, float scale, float rotation = 0f)
 		{
 			var samplers = SetRenderStateForSprite(s);
-			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, vertexCount, scale * s.Size, float3.Ones,
+			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, nv, scale * s.Size, float3.Ones,
 								1f, rotation);
-			vertexCount += 4;
+			nv += 6;
 		}
 
 		public void DrawSprite(Sprite s, PaletteReference pal, in float3 location, float scale = 1f, float rotation = 0f)
@@ -150,13 +149,13 @@ namespace OpenRA.Graphics
 			DrawSprite(s, ResolveTextureIndex(s, pal), location, scale, rotation);
 		}
 
-		internal void DrawSprite(Sprite s, int paletteTextureIndex, in float3 location, float scale, in float3 tint, float alpha,
+		internal void DrawSprite(Sprite s, float paletteTextureIndex, in float3 location, float scale, in float3 tint, float alpha,
 			float rotation = 0f)
 		{
 			var samplers = SetRenderStateForSprite(s);
-			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, vertexCount, scale * s.Size, tint, alpha,
+			Util.FastCreateQuad(vertices, location + scale * s.Offset, s, samplers, paletteTextureIndex, nv, scale * s.Size, tint, alpha,
 								rotation);
-			vertexCount += 4;
+			nv += 6;
 		}
 
 		public void DrawSprite(Sprite s, PaletteReference pal, in float3 location, float scale, in float3 tint, float alpha,
@@ -165,14 +164,14 @@ namespace OpenRA.Graphics
 			DrawSprite(s, ResolveTextureIndex(s, pal), location, scale, tint, alpha, rotation);
 		}
 
-		internal void DrawSprite(Sprite s, int paletteTextureIndex, in float3 a, in float3 b, in float3 c, in float3 d, in float3 tint, float alpha)
+		internal void DrawSprite(Sprite s, float paletteTextureIndex, in float3 a, in float3 b, in float3 c, in float3 d, in float3 tint, float alpha)
 		{
 			var samplers = SetRenderStateForSprite(s);
-			Util.FastCreateQuad(vertices, a, b, c, d, s, samplers, paletteTextureIndex, tint, alpha, vertexCount);
-			vertexCount += 4;
+			Util.FastCreateQuad(vertices, a, b, c, d, s, samplers, paletteTextureIndex, tint, alpha, nv);
+			nv += 6;
 		}
 
-		public void DrawVertexBuffer(IVertexBuffer<Vertex> buffer, IIndexBuffer indices, int start, int length, IEnumerable<Sheet> sheets, BlendMode blendMode)
+		public void DrawVertexBuffer(IVertexBuffer<Vertex> buffer, int start, int length, PrimitiveType type, IEnumerable<Sheet> sheets, BlendMode blendMode)
 		{
 			var i = 0;
 			foreach (var s in sheets)
@@ -186,7 +185,7 @@ namespace OpenRA.Graphics
 
 			renderer.Context.SetBlendMode(blendMode);
 			shader.PrepareRender();
-			renderer.DrawQuadBatch(buffer, indices, shader, length, UintSize * start);
+			renderer.DrawBatch(buffer, start, length, type);
 			renderer.Context.SetBlendMode(BlendMode.None);
 		}
 
@@ -197,32 +196,29 @@ namespace OpenRA.Graphics
 		}
 
 		// For RGBAColorRenderer
-		internal void DrawRGBAQuad(Vertex[] v, BlendMode blendMode)
+		internal void DrawRGBAVertices(Vertex[] v, BlendMode blendMode)
 		{
 			renderer.CurrentBatchRenderer = this;
 
-			if (currentBlend != blendMode || vertexCount + 4 > renderer.TempVertexBufferSize)
+			if (currentBlend != blendMode || nv + v.Length > renderer.TempBufferSize)
 				Flush();
 
 			currentBlend = blendMode;
-
-			Array.Copy(v, 0, vertices, vertexCount, v.Length);
-			vertexCount += 4;
+			Array.Copy(v, 0, vertices, nv, v.Length);
+			nv += v.Length;
 		}
 
-		public void SetPalette(HardwarePalette palette)
+		public void SetPalette(ITexture palette, ITexture colorShifts)
 		{
-			shader.SetTexture("Palette", palette.Texture);
-			shader.SetTexture("ColorShifts", palette.ColorShifts);
-			shader.SetVec("PaletteRows", palette.Height);
+			shader.SetTexture("Palette", palette);
+			shader.SetTexture("ColorShifts", colorShifts);
 		}
 
 		public void SetViewportParams(Size sheetSize, int downscale, float depthMargin, int2 scroll)
 		{
-			// OpenGL only renders x and y coordinates inside [-1, 1] range. We project world coordinates
-			// using p1 to values [0, 2] and then subtract by 1 using p2, where p stands for projection. It's
-			// standard practice for shaders to use a projection matrix, but as we project orthographically
-			// we are able to send less data to the GPU.
+			// Calculate the scale (r1) and offset (r2) that convert from OpenRA viewport pixels
+			// to OpenGL normalized device coordinates (NDC). OpenGL expects coordinates to vary from [-1, 1],
+			// so we rescale viewport pixels to the range [0, 2] using r1 then subtract 1 using r2.
 			var width = 2f / (downscale * sheetSize.Width);
 			var height = 2f / (downscale * sheetSize.Height);
 
@@ -243,8 +239,8 @@ namespace OpenRA.Graphics
 			var depth = depthMargin != 0f ? 2f / (downscale * (sheetSize.Height + depthMargin)) : 0;
 			shader.SetVec("DepthTextureScale", 128 * depth);
 			shader.SetVec("Scroll", scroll.X, scroll.Y, depthMargin != 0f ? scroll.Y : 0);
-			shader.SetVec("p1", width, height, -depth);
-			shader.SetVec("p2", -1, -1, depthMargin != 0f ? 1 : 0);
+			shader.SetVec("r1", width, height, -depth);
+			shader.SetVec("r2", -1, -1, depthMargin != 0f ? 1 : 0);
 		}
 
 		public void SetDepthPreview(bool enabled, float contrast, float offset)

OpenRA.Game/Graphics/TerrainSpriteLayer.cs

@@ -12,15 +12,12 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Runtime.CompilerServices;
 
 namespace OpenRA.Graphics
 {
 	public sealed class TerrainSpriteLayer : IDisposable
 	{
-		// PERF: we can reuse the IndexBuffer as all layers have the same size.
-		static readonly ConditionalWeakTable<World, IndexBufferRc> IndexBuffers = new();
-		readonly IndexBufferRc indexBufferWrapper;
+		static readonly int[] CornerVertexMap = { 0, 1, 2, 2, 3, 0 };
 
 		public readonly BlendMode BlendMode;
 
@@ -31,8 +28,7 @@ namespace OpenRA.Graphics
 		readonly Vertex[] vertices;
 		readonly bool[] ignoreTint;
 		readonly HashSet<int> dirtyRows = new();
-		readonly int indexRowStride;
-		readonly int vertexRowStride;
+		readonly int rowStride;
 		readonly bool restrictToBounds;
 
 		readonly WorldRenderer worldRenderer;
@@ -47,25 +43,19 @@ namespace OpenRA.Graphics
 			this.emptySprite = emptySprite;
 			sheets = new Sheet[SpriteRenderer.SheetCount];
 			BlendMode = blendMode;
+
 			map = world.Map;
+			rowStride = 6 * map.MapSize.X;
 
-			vertexRowStride = 4 * map.MapSize.X;
-			vertices = new Vertex[vertexRowStride * map.MapSize.Y];
-			vertexBuffer = Game.Renderer.Context.CreateVertexBuffer<Vertex>(vertices.Length);
-
-			indexRowStride = 6 * map.MapSize.X;
-			lock (IndexBuffers)
-			{
-				indexBufferWrapper = IndexBuffers.GetValue(world, world => new IndexBufferRc(world));
-				indexBufferWrapper.AddRef();
-			}
-
+			vertices = new Vertex[rowStride * map.MapSize.Y];
 			palettes = new PaletteReference[map.MapSize.X * map.MapSize.Y];
+			vertexBuffer = Game.Renderer.Context.CreateVertexBuffer(vertices.Length);
+
 			wr.PaletteInvalidated += UpdatePaletteIndices;
 
 			if (wr.TerrainLighting != null)
 			{
-				ignoreTint = new bool[vertexRowStride * map.MapSize.Y];
+				ignoreTint = new bool[rowStride * map.MapSize.Y];
 				wr.TerrainLighting.CellChanged += UpdateTint;
 			}
 		}
@@ -75,9 +65,8 @@ namespace OpenRA.Graphics
 			for (var i = 0; i < vertices.Length; i++)
 			{
 				var v = vertices[i];
-				var p = palettes[i / 4]?.TextureIndex ?? 0;
-				var c = (uint)((p & 0xFFFF) << 16) | (v.C & 0xFFFF);
-				vertices[i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, c, v.R, v.G, v.B, v.A);
+				var p = palettes[i / 6]?.TextureIndex ?? 0;
+				vertices[i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, p, v.C, v.R, v.G, v.B, v.A);
 			}
 
 			for (var row = 0; row < map.MapSize.Y; row++)
@@ -108,13 +97,13 @@ namespace OpenRA.Graphics
 
 		void UpdateTint(MPos uv)
 		{
-			var offset = vertexRowStride * uv.V + 4 * uv.U;
+			var offset = rowStride * uv.V + 6 * uv.U;
 			if (ignoreTint[offset])
 			{
-				for (var i = 0; i < 4; i++)
+				for (var i = 0; i < 6; i++)
 				{
 					var v = vertices[offset + i];
-					vertices[offset + i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, v.C, v.A * float3.Ones, v.A);
+					vertices[offset + i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, v.P, v.C, v.A * float3.Ones, v.A);
 				}
 
 				return;
@@ -136,10 +125,10 @@ namespace OpenRA.Graphics
 
 			// Apply tint directly to the underlying vertices
 			// This saves us from having to re-query the sprite information, which has not changed
-			for (var i = 0; i < 4; i++)
+			for (var i = 0; i < 6; i++)
 			{
 				var v = vertices[offset + i];
-				vertices[offset + i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, v.C, v.A * weights[i], v.A);
+				vertices[offset + i] = new Vertex(v.X, v.Y, v.Z, v.S, v.T, v.U, v.V, v.P, v.C, v.A * weights[CornerVertexMap[i]], v.A);
 			}
 
 			dirtyRows.Add(uv.V);
@@ -191,7 +180,7 @@ namespace OpenRA.Graphics
 			if (!map.Tiles.Contains(uv))
 				return;
 
-			var offset = vertexRowStride * uv.V + 4 * uv.U;
+			var offset = rowStride * uv.V + 6 * uv.U;
 			Util.FastCreateQuad(vertices, pos, sprite, samplers, palette?.TextureIndex ?? 0, offset, scale * sprite.Size, alpha * float3.Ones, alpha);
 			palettes[uv.V * map.MapSize.X + uv.U] = palette;
 
@@ -220,13 +209,13 @@ namespace OpenRA.Graphics
 				if (!dirtyRows.Remove(row))
 					continue;
 
-				var rowOffset = vertexRowStride * row;
-				vertexBuffer.SetData(vertices, rowOffset, rowOffset, vertexRowStride);
+				var rowOffset = rowStride * row;
+				vertexBuffer.SetData(vertices, rowOffset, rowOffset, rowStride);
 			}
 
 			Game.Renderer.WorldSpriteRenderer.DrawVertexBuffer(
-				vertexBuffer, indexBufferWrapper.Buffer, indexRowStride * firstRow,
-				indexRowStride * (lastRow - firstRow), sheets, BlendMode);
+				vertexBuffer, rowStride * firstRow, rowStride * (lastRow - firstRow),
+				PrimitiveType.TriangleList, sheets, BlendMode);
 
 			Game.Renderer.Flush();
 		}
@@ -238,29 +227,6 @@ namespace OpenRA.Graphics
 				worldRenderer.TerrainLighting.CellChanged -= UpdateTint;
 
 			vertexBuffer.Dispose();
-
-			lock (IndexBuffers)
-				indexBufferWrapper.Dispose();
-		}
-
-		sealed class IndexBufferRc : IDisposable
-		{
-			public IIndexBuffer Buffer;
-			int count;
-
-			public IndexBufferRc(World world)
-			{
-				Buffer = Game.Renderer.Context.CreateIndexBuffer(Util.CreateQuadIndices(world.Map.MapSize.X * world.Map.MapSize.Y));
-			}
-
-			public void AddRef() { count++; }
-
-			public void Dispose()
-			{
-				count--;
-				if (count == 0)
-					Buffer.Dispose();
-			}
 		}
 	}
 }

OpenRA.Game/Graphics/Util.cs

@@ -10,7 +10,6 @@
 #endregion
 
 using System;
-using System.Runtime.InteropServices;
 using OpenRA.FileFormats;
 using OpenRA.Primitives;
 
@@ -21,17 +20,7 @@ namespace OpenRA.Graphics
 		// yes, our channel order is nuts.
 		static readonly int[] ChannelMasks = { 2, 1, 0, 3 };
 
-		public static uint[] CreateQuadIndices(int quads)
-		{
-			var indices = new uint[quads * 6];
-			ReadOnlySpan<uint> cornerVertexMap = stackalloc uint[] { 0, 1, 2, 2, 3, 0 };
-			for (var i = 0; i < indices.Length; i++)
-				indices[i] = cornerVertexMap[i % 6] + (uint)(4 * (i / 6));
-
-			return indices;
-		}
-
-		public static void FastCreateQuad(Vertex[] vertices, in float3 o, Sprite r, int2 samplers, int paletteTextureIndex, int nv,
+		public static void FastCreateQuad(Vertex[] vertices, in float3 o, Sprite r, int2 samplers, float paletteTextureIndex, int nv,
 			in float3 size, in float3 tint, float alpha, float rotation = 0f)
 		{
 			float3 a, b, c, d;
@@ -73,7 +62,7 @@ namespace OpenRA.Graphics
 
 		public static void FastCreateQuad(Vertex[] vertices,
 			in float3 a, in float3 b, in float3 c, in float3 d,
-			Sprite r, int2 samplers, int paletteTextureIndex,
+			Sprite r, int2 samplers, float paletteTextureIndex,
 			in float3 tint, float alpha, int nv)
 		{
 			float sl = 0;
@@ -95,33 +84,76 @@ namespace OpenRA.Graphics
 				attribC |= samplers.Y << 9;
 			}
 
-			attribC |= (paletteTextureIndex & 0xFFFF) << 16;
-
-			var uAttribC = (uint)attribC;
-			vertices[nv] = new Vertex(a, r.Left, r.Top, sl, st, uAttribC, tint, alpha);
-			vertices[nv + 1] = new Vertex(b, r.Right, r.Top, sr, st, uAttribC, tint, alpha);
-			vertices[nv + 2] = new Vertex(c, r.Right, r.Bottom, sr, sb, uAttribC, tint, alpha);
-			vertices[nv + 3] = new Vertex(d, r.Left, r.Bottom, sl, sb, uAttribC, tint, alpha);
+			var fAttribC = (float)attribC;
+			vertices[nv] = new Vertex(a, r.Left, r.Top, sl, st, paletteTextureIndex, fAttribC, tint, alpha);
+			vertices[nv + 1] = new Vertex(b, r.Right, r.Top, sr, st, paletteTextureIndex, fAttribC, tint, alpha);
+			vertices[nv + 2] = new Vertex(c, r.Right, r.Bottom, sr, sb, paletteTextureIndex, fAttribC, tint, alpha);
+			vertices[nv + 3] = new Vertex(c, r.Right, r.Bottom, sr, sb, paletteTextureIndex, fAttribC, tint, alpha);
+			vertices[nv + 4] = new Vertex(d, r.Left, r.Bottom, sl, sb, paletteTextureIndex, fAttribC, tint, alpha);
+			vertices[nv + 5] = new Vertex(a, r.Left, r.Top, sl, st, paletteTextureIndex, fAttribC, tint, alpha);
 		}
 
-		public static void FastCopyIntoChannel(Sprite dest, byte[] src, SpriteFrameType srcType, bool premultiplied = false)
+		public static void FastCopyIntoChannel(Sprite dest, byte[] src, SpriteFrameType srcType)
 		{
 			var destData = dest.Sheet.GetData();
-			var stride = dest.Sheet.Size.Width;
-			var x = dest.Bounds.Left;
-			var y = dest.Bounds.Top;
 			var width = dest.Bounds.Width;
 			var height = dest.Bounds.Height;
 
 			if (dest.Channel == TextureChannel.RGBA)
 			{
-				CopyIntoRgba(src, srcType, premultiplied, destData, x, y, width, height, stride);
+				var destStride = dest.Sheet.Size.Width;
+				unsafe
+				{
+					// Cast the data to an int array so we can copy the src data directly
+					fixed (byte* bd = &destData[0])
+					{
+						var data = (int*)bd;
+						var x = dest.Bounds.Left;
+						var y = dest.Bounds.Top;
+
+						var k = 0;
+						for (var j = 0; j < height; j++)
+						{
+							for (var i = 0; i < width; i++)
+							{
+								byte r, g, b, a;
+								switch (srcType)
+								{
+									case SpriteFrameType.Bgra32:
+									case SpriteFrameType.Bgr24:
+									{
+										b = src[k++];
+										g = src[k++];
+										r = src[k++];
+										a = srcType == SpriteFrameType.Bgra32 ? src[k++] : (byte)255;
+										break;
+									}
+
+									case SpriteFrameType.Rgba32:
+									case SpriteFrameType.Rgb24:
+									{
+										r = src[k++];
+										g = src[k++];
+										b = src[k++];
+										a = srcType == SpriteFrameType.Rgba32 ? src[k++] : (byte)255;
+										break;
+									}
+
+									default:
+										throw new InvalidOperationException($"Unknown SpriteFrameType {srcType}");
+								}
+
+								var cc = Color.FromArgb(a, r, g, b);
+								data[(y + j) * destStride + x + i] = PremultiplyAlpha(cc).ToArgb();
+							}
+						}
+					}
+				}
 			}
 			else
 			{
-				// Copy into single channel of destination.
-				var destStride = stride * 4;
-				var destOffset = destStride * y + x * 4 + ChannelMasks[(int)dest.Channel];
+				var destStride = dest.Sheet.Size.Width * 4;
+				var destOffset = destStride * dest.Bounds.Top + dest.Bounds.Left * 4 + ChannelMasks[(int)dest.Channel];
 				var destSkip = destStride - 4 * width;
 
 				var srcOffset = 0;
@@ -138,119 +170,56 @@ namespace OpenRA.Graphics
 			}
 		}
 
-		static void CopyIntoRgba(
-			byte[] src, SpriteFrameType srcType, bool premultiplied, byte[] dest, int x, int y, int width, int height, int stride)
-		{
-			var si = 0;
-			var di = y * stride + x;
-			var d = MemoryMarshal.Cast<byte, uint>(dest);
-
-			// SpriteFrameType.Brga32 is a common source format, and it matches the destination format.
-			// Provide a fast past that just performs memory copies.
-			if (srcType == SpriteFrameType.Bgra32)
-			{
-				var s = MemoryMarshal.Cast<byte, uint>(src);
-				for (var h = 0; h < height; h++)
-				{
-					s[si..(si + width)].CopyTo(d[di..(di + width)]);
-
-					if (!premultiplied)
-					{
-						for (var w = 0; w < width; w++)
-						{
-							d[di] = PremultiplyAlpha(Color.FromArgb(d[di])).ToArgb();
-							di++;
-						}
-
-						di -= width;
-					}
-
-					si += width;
-					di += stride;
-				}
-
-				return;
-			}
-
-			for (var h = 0; h < height; h++)
-			{
-				for (var w = 0; w < width; w++)
-				{
-					byte r, g, b, a;
-					switch (srcType)
-					{
-						case SpriteFrameType.Bgra32:
-						case SpriteFrameType.Bgr24:
-							b = src[si++];
-							g = src[si++];
-							r = src[si++];
-							a = srcType == SpriteFrameType.Bgra32 ? src[si++] : byte.MaxValue;
-							break;
-
-						case SpriteFrameType.Rgba32:
-						case SpriteFrameType.Rgb24:
-							r = src[si++];
-							g = src[si++];
-							b = src[si++];
-							a = srcType == SpriteFrameType.Rgba32 ? src[si++] : byte.MaxValue;
-							break;
-
-						default:
-							throw new InvalidOperationException($"Unknown SpriteFrameType {srcType}");
-					}
-
-					var c = Color.FromArgb(a, r, g, b);
-					if (!premultiplied)
-						c = PremultiplyAlpha(c);
-					d[di++] = c.ToArgb();
-				}
-
-				di += stride - width;
-			}
-		}
-
 		public static void FastCopyIntoSprite(Sprite dest, Png src)
 		{
 			var destData = dest.Sheet.GetData();
-			var stride = dest.Sheet.Size.Width;
-			var x = dest.Bounds.Left;
-			var y = dest.Bounds.Top;
+			var destStride = dest.Sheet.Size.Width;
 			var width = dest.Bounds.Width;
 			var height = dest.Bounds.Height;
 
-			var si = 0;
-			var di = y * stride + x;
-			var d = MemoryMarshal.Cast<byte, uint>(destData);
-
-			for (var h = 0; h < height; h++)
+			unsafe
 			{
-				for (var w = 0; w < width; w++)
+				// Cast the data to an int array so we can copy the src data directly
+				fixed (byte* bd = &destData[0])
 				{
-					Color c;
-					switch (src.Type)
+					var data = (int*)bd;
+					var x = dest.Bounds.Left;
+					var y = dest.Bounds.Top;
+
+					var k = 0;
+					for (var j = 0; j < height; j++)
 					{
-						case SpriteFrameType.Indexed8:
-							c = src.Palette[src.Data[si++]];
-							break;
+						for (var i = 0; i < width; i++)
+						{
+							Color cc;
+							switch (src.Type)
+							{
+								case SpriteFrameType.Indexed8:
+								{
+									cc = src.Palette[src.Data[k++]];
+									break;
+								}
 
-						case SpriteFrameType.Rgba32:
-						case SpriteFrameType.Rgb24:
-							var r = src.Data[si++];
-							var g = src.Data[si++];
-							var b = src.Data[si++];
-							var a = src.Type == SpriteFrameType.Rgba32 ? src.Data[si++] : byte.MaxValue;
-							c = Color.FromArgb(a, r, g, b);
-							break;
+								case SpriteFrameType.Rgba32:
+								case SpriteFrameType.Rgb24:
+								{
+									var r = src.Data[k++];
+									var g = src.Data[k++];
+									var b = src.Data[k++];
+									var a = src.Type == SpriteFrameType.Rgba32 ? src.Data[k++] : (byte)255;
+									cc = Color.FromArgb(a, r, g, b);
+									break;
+								}
 
-						// PNGs don't support BGR[A], so no need to include them here
-						default:
-							throw new InvalidOperationException($"Unknown SpriteFrameType {src.Type}");
+								// Pngs don't support BGR[A], so no need to include them here
+								default:
+									throw new InvalidOperationException($"Unknown SpriteFrameType {src.Type}");
+							}
+
+							data[(y + j) * destStride + x + i] = PremultiplyAlpha(cc).ToArgb();
+						}
 					}
-
-					d[di++] = PremultiplyAlpha(c).ToArgb();
 				}
-
-				di += stride - width;
 			}
 		}
 
@@ -336,5 +305,239 @@ namespace OpenRA.Graphics
 				(int)((byte)(t * a2 * c2.G + 0.5f) + (1 - t) * (byte)(a1 * c1.G + 0.5f)),
 				(int)((byte)(t * a2 * c2.B + 0.5f) + (1 - t) * (byte)(a1 * c1.B + 0.5f))));
 		}
+
+		public static float[] IdentityMatrix()
+		{
+			return Exts.MakeArray(16, j => (j % 5 == 0) ? 1.0f : 0);
+		}
+
+		public static float[] ScaleMatrix(float sx, float sy, float sz)
+		{
+			var mtx = IdentityMatrix();
+			mtx[0] = sx;
+			mtx[5] = sy;
+			mtx[10] = sz;
+			return mtx;
+		}
+
+		public static float[] TranslationMatrix(float x, float y, float z)
+		{
+			var mtx = IdentityMatrix();
+			mtx[12] = x;
+			mtx[13] = y;
+			mtx[14] = z;
+			return mtx;
+		}
+
+		public static float[] MatrixMultiply(float[] lhs, float[] rhs)
+		{
+			var mtx = new float[16];
+			for (var i = 0; i < 4; i++)
+				for (var j = 0; j < 4; j++)
+				{
+					mtx[4 * i + j] = 0;
+					for (var k = 0; k < 4; k++)
+						mtx[4 * i + j] += lhs[4 * k + j] * rhs[4 * i + k];
+				}
+
+			return mtx;
+		}
+
+		public static float[] MatrixVectorMultiply(float[] mtx, float[] vec)
+		{
+			var ret = new float[4];
+			for (var j = 0; j < 4; j++)
+			{
+				ret[j] = 0;
+				for (var k = 0; k < 4; k++)
+					ret[j] += mtx[4 * k + j] * vec[k];
+			}
+
+			return ret;
+		}
+
+		public static float[] MatrixInverse(float[] m)
+		{
+			var mtx = new float[16];
+
+			mtx[0] = m[5] * m[10] * m[15] -
+				m[5] * m[11] * m[14] -
+				m[9] * m[6] * m[15] +
+				m[9] * m[7] * m[14] +
+				m[13] * m[6] * m[11] -
+				m[13] * m[7] * m[10];
+
+			mtx[4] = -m[4] * m[10] * m[15] +
+				m[4] * m[11] * m[14] +
+				m[8] * m[6] * m[15] -
+				m[8] * m[7] * m[14] -
+				m[12] * m[6] * m[11] +
+				m[12] * m[7] * m[10];
+
+			mtx[8] = m[4] * m[9] * m[15] -
+				m[4] * m[11] * m[13] -
+				m[8] * m[5] * m[15] +
+				m[8] * m[7] * m[13] +
+				m[12] * m[5] * m[11] -
+				m[12] * m[7] * m[9];
+
+			mtx[12] = -m[4] * m[9] * m[14] +
+				m[4] * m[10] * m[13] +
+				m[8] * m[5] * m[14] -
+				m[8] * m[6] * m[13] -
+				m[12] * m[5] * m[10] +
+				m[12] * m[6] * m[9];
+
+			mtx[1] = -m[1] * m[10] * m[15] +
+				m[1] * m[11] * m[14] +
+				m[9] * m[2] * m[15] -
+				m[9] * m[3] * m[14] -
+				m[13] * m[2] * m[11] +
+				m[13] * m[3] * m[10];
+
+			mtx[5] = m[0] * m[10] * m[15] -
+				m[0] * m[11] * m[14] -
+				m[8] * m[2] * m[15] +
+				m[8] * m[3] * m[14] +
+				m[12] * m[2] * m[11] -
+				m[12] * m[3] * m[10];
+
+			mtx[9] = -m[0] * m[9] * m[15] +
+				m[0] * m[11] * m[13] +
+				m[8] * m[1] * m[15] -
+				m[8] * m[3] * m[13] -
+				m[12] * m[1] * m[11] +
+				m[12] * m[3] * m[9];
+
+			mtx[13] = m[0] * m[9] * m[14] -
+				m[0] * m[10] * m[13] -
+				m[8] * m[1] * m[14] +
+				m[8] * m[2] * m[13] +
+				m[12] * m[1] * m[10] -
+				m[12] * m[2] * m[9];
+
+			mtx[2] = m[1] * m[6] * m[15] -
+				m[1] * m[7] * m[14] -
+				m[5] * m[2] * m[15] +
+				m[5] * m[3] * m[14] +
+				m[13] * m[2] * m[7] -
+				m[13] * m[3] * m[6];
+
+			mtx[6] = -m[0] * m[6] * m[15] +
+				m[0] * m[7] * m[14] +
+				m[4] * m[2] * m[15] -
+				m[4] * m[3] * m[14] -
+				m[12] * m[2] * m[7] +
+				m[12] * m[3] * m[6];
+
+			mtx[10] = m[0] * m[5] * m[15] -
+				m[0] * m[7] * m[13] -
+				m[4] * m[1] * m[15] +
+				m[4] * m[3] * m[13] +
+				m[12] * m[1] * m[7] -
+				m[12] * m[3] * m[5];
+
+			mtx[14] = -m[0] * m[5] * m[14] +
+				m[0] * m[6] * m[13] +
+				m[4] * m[1] * m[14] -
+				m[4] * m[2] * m[13] -
+				m[12] * m[1] * m[6] +
+				m[12] * m[2] * m[5];
+
+			mtx[3] = -m[1] * m[6] * m[11] +
+				m[1] * m[7] * m[10] +
+				m[5] * m[2] * m[11] -
+				m[5] * m[3] * m[10] -
+				m[9] * m[2] * m[7] +
+				m[9] * m[3] * m[6];
+
+			mtx[7] = m[0] * m[6] * m[11] -
+				m[0] * m[7] * m[10] -
+				m[4] * m[2] * m[11] +
+				m[4] * m[3] * m[10] +
+				m[8] * m[2] * m[7] -
+				m[8] * m[3] * m[6];
+
+			mtx[11] = -m[0] * m[5] * m[11] +
+				m[0] * m[7] * m[9] +
+				m[4] * m[1] * m[11] -
+				m[4] * m[3] * m[9] -
+				m[8] * m[1] * m[7] +
+				m[8] * m[3] * m[5];
+
+			mtx[15] = m[0] * m[5] * m[10] -
+				m[0] * m[6] * m[9] -
+				m[4] * m[1] * m[10] +
+				m[4] * m[2] * m[9] +
+				m[8] * m[1] * m[6] -
+				m[8] * m[2] * m[5];
+
+			var det = m[0] * mtx[0] + m[1] * mtx[4] + m[2] * mtx[8] + m[3] * mtx[12];
+			if (det == 0)
+				return null;
+
+			for (var i = 0; i < 16; i++)
+				mtx[i] *= 1 / det;
+
+			return mtx;
+		}
+
+		public static float[] MakeFloatMatrix(Int32Matrix4x4 imtx)
+		{
+			var multipler = 1f / imtx.M44;
+			return new[]
+			{
+				imtx.M11 * multipler,
+				imtx.M12 * multipler,
+				imtx.M13 * multipler,
+				imtx.M14 * multipler,
+
+				imtx.M21 * multipler,
+				imtx.M22 * multipler,
+				imtx.M23 * multipler,
+				imtx.M24 * multipler,
+
+				imtx.M31 * multipler,
+				imtx.M32 * multipler,
+				imtx.M33 * multipler,
+				imtx.M34 * multipler,
+
+				imtx.M41 * multipler,
+				imtx.M42 * multipler,
+				imtx.M43 * multipler,
+				imtx.M44 * multipler,
+			};
+		}
+
+		public static float[] MatrixAABBMultiply(float[] mtx, float[] bounds)
+		{
+			// Corner offsets
+			var ix = new uint[] { 0, 0, 0, 0, 3, 3, 3, 3 };
+			var iy = new uint[] { 1, 1, 4, 4, 1, 1, 4, 4 };
+			var iz = new uint[] { 2, 5, 2, 5, 2, 5, 2, 5 };
+
+			// Vectors to opposing corner
+			var ret = new[]
+			{
+				float.MaxValue, float.MaxValue, float.MaxValue,
+				float.MinValue, float.MinValue, float.MinValue
+			};
+
+			// Transform vectors and find new bounding box
+			for (var i = 0; i < 8; i++)
+			{
+				var vec = new[] { bounds[ix[i]], bounds[iy[i]], bounds[iz[i]], 1 };
+				var tvec = MatrixVectorMultiply(mtx, vec);
+
+				ret[0] = Math.Min(ret[0], tvec[0] / tvec[3]);
+				ret[1] = Math.Min(ret[1], tvec[1] / tvec[3]);
+				ret[2] = Math.Min(ret[2], tvec[2] / tvec[3]);
+				ret[3] = Math.Max(ret[3], tvec[0] / tvec[3]);
+				ret[4] = Math.Max(ret[4], tvec[1] / tvec[3]);
+				ret[5] = Math.Max(ret[5], tvec[2] / tvec[3]);
+			}
+
+			return ret;
+		}
 	}
 }

OpenRA.Game/Graphics/Vertex.cs

@@ -23,42 +23,27 @@ namespace OpenRA.Graphics
 		public readonly float S, T, U, V;
 
 		// Palette and channel flags
-		public readonly uint C;
+		public readonly float P, C;
 
 		// Color tint
 		public readonly float R, G, B, A;
 
-		public Vertex(in float3 xyz, float s, float t, float u, float v, uint c)
-			: this(xyz.X, xyz.Y, xyz.Z, s, t, u, v, c, float3.Ones, 1f) { }
+		public Vertex(in float3 xyz, float s, float t, float u, float v, float p, float c)
+			: this(xyz.X, xyz.Y, xyz.Z, s, t, u, v, p, c, float3.Ones, 1f) { }
 
-		public Vertex(in float3 xyz, float s, float t, float u, float v, uint c, in float3 tint, float a)
-			: this(xyz.X, xyz.Y, xyz.Z, s, t, u, v, c, tint.X, tint.Y, tint.Z, a) { }
+		public Vertex(in float3 xyz, float s, float t, float u, float v, float p, float c, in float3 tint, float a)
+			: this(xyz.X, xyz.Y, xyz.Z, s, t, u, v, p, c, tint.X, tint.Y, tint.Z, a) { }
 
-		public Vertex(float x, float y, float z, float s, float t, float u, float v, uint c, in float3 tint, float a)
-			: this(x, y, z, s, t, u, v, c, tint.X, tint.Y, tint.Z, a) { }
+		public Vertex(float x, float y, float z, float s, float t, float u, float v, float p, float c, in float3 tint, float a)
+			: this(x, y, z, s, t, u, v, p, c, tint.X, tint.Y, tint.Z, a) { }
 
-		public Vertex(float x, float y, float z, float s, float t, float u, float v, uint c, float r, float g, float b, float a)
+		public Vertex(float x, float y, float z, float s, float t, float u, float v, float p, float c, float r, float g, float b, float a)
 		{
 			X = x; Y = y; Z = z;
 			S = s; T = t;
 			U = u; V = v;
-			C = c;
+			P = p; C = c;
 			R = r; G = g; B = b; A = a;
 		}
 	}
-
-	public sealed class CombinedShaderBindings : ShaderBindings
-	{
-		public CombinedShaderBindings()
-			: base("combined")
-		{ }
-
-		public override ShaderVertexAttribute[] Attributes { get; } = new[]
-		{
-			new ShaderVertexAttribute("aVertexPosition", ShaderVertexAttributeType.Float, 3, 0),
-			new ShaderVertexAttribute("aVertexTexCoord", ShaderVertexAttributeType.Float, 4, 12),
-			new ShaderVertexAttribute("aVertexAttributes", ShaderVertexAttributeType.UInt, 1, 28),
-			new ShaderVertexAttribute("aVertexTint", ShaderVertexAttributeType.Float, 4, 32)
-		};
-	}
 }

OpenRA.Game/Graphics/Viewport.cs

@@ -282,23 +282,11 @@ namespace OpenRA.Graphics
 		IEnumerable<MPos> CandidateMouseoverCells(int2 world)
 		{
 			var map = worldRenderer.World.Map;
-			var tileScale = map.Grid.TileScale / 2;
 			var minPos = worldRenderer.ProjectedPosition(world);
 
-			// Find all the cells that could potentially have been clicked.
-			MPos a;
-			MPos b;
-			if (map.Grid.Type == MapGridType.RectangularIsometric)
-			{
-				// TODO: this generates too many cells.
-				a = map.CellContaining(minPos - new WVec(tileScale, 0, 0)).ToMPos(map.Grid.Type);
-				b = map.CellContaining(minPos + new WVec(tileScale, tileScale * map.Grid.MaximumTerrainHeight, 0)).ToMPos(map.Grid.Type);
-			}
-			else
-			{
-				a = map.CellContaining(minPos).ToMPos(map.Grid.Type);
-				b = map.CellContaining(minPos + new WVec(0, tileScale * map.Grid.MaximumTerrainHeight, 0)).ToMPos(map.Grid.Type);
-			}
+			// Find all the cells that could potentially have been clicked
+			var a = map.CellContaining(minPos - new WVec(1024, 0, 0)).ToMPos(map.Grid.Type);
+			var b = map.CellContaining(minPos + new WVec(512, 512 * map.Grid.MaximumTerrainHeight, 0)).ToMPos(map.Grid.Type);
 
 			for (var v = b.V; v >= a.V; v--)
 				for (var u = b.U; u >= a.U; u--)
@@ -311,13 +299,10 @@ namespace OpenRA.Graphics
 
 		public void Center(IEnumerable<Actor> actors)
 		{
-			var actorsCollection = actors as IReadOnlyCollection<Actor>;
-			actorsCollection ??= actors.ToList();
-
-			if (actorsCollection.Count == 0)
+			if (!actors.Any())
 				return;
 
-			Center(actorsCollection.Select(a => a.CenterPosition).Average());
+			Center(actors.Select(a => a.CenterPosition).Average());
 		}
 
 		public void Center(WPos pos)

OpenRA.Game/Graphics/WorldRenderer.cs

@@ -44,8 +44,6 @@ namespace OpenRA.Graphics
 		readonly List<IFinalizedRenderable> preparedAnnotationRenderables = new();
 
 		readonly List<IRenderable> renderablesBuffer = new();
-		readonly IRenderer[] renderers;
-		readonly IRenderPostProcessPass[] postProcessPasses;
 
 		internal WorldRenderer(ModData modData, World world)
 		{
@@ -68,24 +66,9 @@ namespace OpenRA.Graphics
 			palette.Initialize();
 
 			TerrainLighting = world.WorldActor.TraitOrDefault<ITerrainLighting>();
-			renderers = world.WorldActor.TraitsImplementing<IRenderer>().ToArray();
 			terrainRenderer = world.WorldActor.TraitOrDefault<IRenderTerrain>();
 
 			debugVis = Exts.Lazy(() => world.WorldActor.TraitOrDefault<DebugVisualizations>());
-
-			postProcessPasses = world.WorldActor.TraitsImplementing<IRenderPostProcessPass>().ToArray();
-		}
-
-		public void BeginFrame()
-		{
-			foreach (var r in renderers)
-				r.BeginFrame();
-		}
-
-		public void EndFrame()
-		{
-			foreach (var r in renderers)
-				r.EndFrame();
 		}
 
 		public void UpdatePalettesForPlayer(string internalName, Color color, bool replaceExisting)
@@ -287,8 +270,6 @@ namespace OpenRA.Graphics
 			if (enableDepthBuffer)
 				Game.Renderer.ClearDepthBuffer();
 
-			ApplyPostProcessing(PostProcessPassType.AfterActors);
-
 			World.ApplyToActorsWithTrait<IRenderAboveWorld>((actor, trait) =>
 			{
 				if (actor.IsInWorld && !actor.Disposed)
@@ -298,8 +279,6 @@ namespace OpenRA.Graphics
 			if (enableDepthBuffer)
 				Game.Renderer.ClearDepthBuffer();
 
-			ApplyPostProcessing(PostProcessPassType.AfterWorld);
-
 			World.ApplyToActorsWithTrait<IRenderShroud>((actor, trait) => trait.RenderShroud(this));
 
 			if (enableDepthBuffer)
@@ -313,23 +292,9 @@ namespace OpenRA.Graphics
 				foreach (var r in g)
 					r.Render(this);
 
-			ApplyPostProcessing(PostProcessPassType.AfterShroud);
-
 			Game.Renderer.Flush();
 		}
 
-		void ApplyPostProcessing(PostProcessPassType type)
-		{
-			foreach (var pass in postProcessPasses)
-			{
-				if (pass.Type != type || !pass.Enabled)
-					continue;
-
-				Game.Renderer.Flush();
-				pass.Draw(this);
-			}
-		}
-
 		public void DrawAnnotations()
 		{
 			Game.Renderer.EnableAntialiasingFilter();

OpenRA.Game/HotkeyDefinition.cs

@@ -10,6 +10,7 @@
 #endregion
 
 using System.Collections.Generic;
+using System.Linq;
 
 namespace OpenRA
 {
@@ -30,26 +31,29 @@ namespace OpenRA
 			if (!string.IsNullOrEmpty(node.Value))
 				Default = FieldLoader.GetValue<Hotkey>("value", node.Value);
 
-			var nodeDict = node.ToDictionary();
+			var descriptionNode = node.Nodes.FirstOrDefault(n => n.Key == "Description");
+			if (descriptionNode != null)
+				Description = descriptionNode.Value.Value;
 
-			if (nodeDict.TryGetValue("Description", out var descriptionYaml))
-				Description = descriptionYaml.Value;
+			var typesNode = node.Nodes.FirstOrDefault(n => n.Key == "Types");
+			if (typesNode != null)
+				Types = FieldLoader.GetValue<HashSet<string>>("Types", typesNode.Value.Value);
 
-			if (nodeDict.TryGetValue("Types", out var typesYaml))
-				Types = FieldLoader.GetValue<HashSet<string>>("Types", typesYaml.Value);
+			var contextsNode = node.Nodes.FirstOrDefault(n => n.Key == "Contexts");
+			if (contextsNode != null)
+				Contexts = FieldLoader.GetValue<HashSet<string>>("Contexts", contextsNode.Value.Value);
 
-			if (nodeDict.TryGetValue("Contexts", out var contextYaml))
-				Contexts = FieldLoader.GetValue<HashSet<string>>("Contexts", contextYaml.Value);
-
-			if (nodeDict.TryGetValue("Platform", out var platformYaml))
+			var platformNode = node.Nodes.FirstOrDefault(n => n.Key == "Platform");
+			if (platformNode != null)
 			{
-				var platformOverride = platformYaml.NodeWithKeyOrDefault(Platform.CurrentPlatform.ToString());
+				var platformOverride = platformNode.Value.Nodes.FirstOrDefault(n => n.Key == Platform.CurrentPlatform.ToString());
 				if (platformOverride != null)
 					Default = FieldLoader.GetValue<Hotkey>("value", platformOverride.Value.Value);
 			}
 
-			if (nodeDict.TryGetValue("Readonly", out var readonlyYaml))
-				Readonly = FieldLoader.GetValue<bool>("Readonly", readonlyYaml.Value);
+			var readonlyNode = node.Nodes.FirstOrDefault(n => n.Key == "Readonly");
+			if (readonlyNode != null)
+				Readonly = FieldLoader.GetValue<bool>("Readonly", readonlyNode.Value.Value);
 		}
 	}
 }

OpenRA.Game/LocalPlayerProfile.cs

@@ -84,11 +84,10 @@ namespace OpenRA
 				{
 					var client = HttpClientFactory.Create();
 
-					var url = playerDatabase.Profile + Fingerprint;
-					var httpResponseMessage = await client.GetAsync(url);
+					var httpResponseMessage = await client.GetAsync(playerDatabase.Profile + Fingerprint);
 					var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-					var yaml = MiniYaml.FromStream(result, url).First();
+					var yaml = MiniYaml.FromStream(result).First();
 					if (yaml.Key == "Player")
 					{
 						innerData = FieldLoader.Load<PlayerProfile>(yaml.Value);

OpenRA.Game/Manifest.cs

@@ -43,6 +43,17 @@ namespace OpenRA
 		}
 	}
 
+	public sealed class ModelSequenceFormat : IGlobalModData
+	{
+		public readonly string Type;
+		public readonly IReadOnlyDictionary<string, MiniYaml> Metadata;
+		public ModelSequenceFormat(MiniYaml yaml)
+		{
+			Type = yaml.Value;
+			Metadata = new ReadOnlyDictionary<string, MiniYaml>(yaml.ToDictionary());
+		}
+	}
+
 	public class ModMetadata
 	{
 		public string Title;
@@ -94,8 +105,7 @@ namespace OpenRA
 			Id = modId;
 			Package = package;
 
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
-			var nodes = MiniYaml.FromStream(package.GetStream("mod.yaml"), $"{package.Name}:mod.yaml", stringPool: stringPool);
+			var nodes = MiniYaml.FromStream(package.GetStream("mod.yaml"), "mod.yaml");
 			for (var i = nodes.Count - 1; i >= 0; i--)
 			{
 				if (nodes[i].Key != "Include")
@@ -108,7 +118,7 @@ namespace OpenRA
 					throw new YamlException($"{nodes[i].Location}: File `{filename}` not found.");
 
 				nodes.RemoveAt(i);
-				nodes.InsertRange(i, MiniYaml.FromStream(contents, $"{package.Name}:{filename}", stringPool: stringPool));
+				nodes.InsertRange(i, MiniYaml.FromStream(contents, filename));
 			}
 
 			// Merge inherited overrides
@@ -201,18 +211,18 @@ namespace OpenRA
 
 		static string[] YamlList(Dictionary<string, MiniYaml> yaml, string key)
 		{
-			if (!yaml.TryGetValue(key, out var value))
+			if (!yaml.ContainsKey(key))
 				return Array.Empty<string>();
 
-			return value.Nodes.Select(n => n.Key).ToArray();
+			return yaml[key].ToDictionary().Keys.ToArray();
 		}
 
 		static IReadOnlyDictionary<string, string> YamlDictionary(Dictionary<string, MiniYaml> yaml, string key)
 		{
-			if (!yaml.TryGetValue(key, out var value))
+			if (!yaml.ContainsKey(key))
 				return new Dictionary<string, string>();
 
-			return value.ToDictionary(my => my.Value);
+			return yaml[key].ToDictionary(my => my.Value);
 		}
 
 		public bool Contains<T>() where T : IGlobalModData

OpenRA.Game/Map/ActorInitializer.cs

@@ -175,7 +175,8 @@ namespace OpenRA
 		protected CompositeActorInit(TraitInfo info)
 			: base(info.InstanceName) { }
 
-		protected CompositeActorInit() { }
+		protected CompositeActorInit()
+			: base() { }
 
 		public virtual void Initialize(MiniYaml yaml)
 		{

OpenRA.Game/Map/ActorReference.cs

@@ -84,7 +84,7 @@ namespace OpenRA
 
 		public MiniYaml Save(Func<ActorInit, bool> initFilter = null)
 		{
-			var nodes = new List<MiniYamlNode>();
+			var ret = new MiniYaml(Type);
 			foreach (var o in initDict.Value)
 			{
 				if (o is not ActorInit init || o is ISuppressInitExport)
@@ -98,10 +98,10 @@ namespace OpenRA
 				if (!string.IsNullOrEmpty(init.InstanceName))
 					initName += ActorInfo.TraitInstanceSeparator + init.InstanceName;
 
-				nodes.Add(new MiniYamlNode(initName, init.Save()));
+				ret.Nodes.Add(new MiniYamlNode(initName, init.Save()));
 			}
 
-			return new MiniYaml(Type, nodes);
+			return ret;
 		}
 
 		public IEnumerator<object> GetEnumerator() { return initDict.Value.GetEnumerator(); }
@@ -139,7 +139,7 @@ namespace OpenRA
 			return removed;
 		}
 
-		public IReadOnlyCollection<T> GetAll<T>() where T : ActorInit
+		public IEnumerable<T> GetAll<T>() where T : ActorInit
 		{
 			return initDict.Value.WithInterface<T>();
 		}
@@ -152,9 +152,8 @@ namespace OpenRA
 			// If a more specific init is not available, fall back to an unnamed init.
 			// If duplicate inits are defined, take the last to match standard yaml override expectations
 			if (info != null && !string.IsNullOrEmpty(info.InstanceName))
-				return
-					inits.LastOrDefault(i => i.InstanceName == info.InstanceName) ??
-					inits.LastOrDefault(i => string.IsNullOrEmpty(i.InstanceName));
+				return inits.LastOrDefault(i => i.InstanceName == info.InstanceName) ??
+				       inits.LastOrDefault(i => string.IsNullOrEmpty(i.InstanceName));
 
 			// Untagged traits will only use untagged inits
 			return inits.LastOrDefault(i => string.IsNullOrEmpty(i.InstanceName));

OpenRA.Game/Map/CellCoordsRegion.cs

@@ -1,90 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System.Collections;
-using System.Collections.Generic;
-
-namespace OpenRA
-{
-	public readonly struct CellCoordsRegion : IEnumerable<CPos>
-	{
-		public struct CellCoordsEnumerator : IEnumerator<CPos>
-		{
-			readonly CellCoordsRegion r;
-
-			public CellCoordsEnumerator(CellCoordsRegion region)
-				: this()
-			{
-				r = region;
-				Reset();
-			}
-
-			public bool MoveNext()
-			{
-				var x = Current.X + 1;
-				var y = Current.Y;
-
-				// Check for column overflow.
-				if (x > r.BottomRight.X)
-				{
-					y++;
-					x = r.TopLeft.X;
-
-					// Check for row overflow.
-					if (y > r.BottomRight.Y)
-						return false;
-				}
-
-				Current = new CPos(x, y);
-				return true;
-			}
-
-			public void Reset()
-			{
-				Current = new CPos(r.TopLeft.X - 1, r.TopLeft.Y);
-			}
-
-			public CPos Current { get; private set; }
-
-			readonly object IEnumerator.Current => Current;
-			public readonly void Dispose() { }
-		}
-
-		public CellCoordsRegion(CPos topLeft, CPos bottomRight)
-		{
-			TopLeft = topLeft;
-			BottomRight = bottomRight;
-		}
-
-		public override string ToString()
-		{
-			return $"{TopLeft}->{BottomRight}";
-		}
-
-		public CellCoordsEnumerator GetEnumerator()
-		{
-			return new CellCoordsEnumerator(this);
-		}
-
-		IEnumerator<CPos> IEnumerable<CPos>.GetEnumerator()
-		{
-			return GetEnumerator();
-		}
-
-		IEnumerator IEnumerable.GetEnumerator()
-		{
-			return GetEnumerator();
-		}
-
-		public CPos TopLeft { get; }
-		public CPos BottomRight { get; }
-	}
-}

OpenRA.Game/Map/CellRegion.cs

@@ -12,6 +12,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace OpenRA
 {
@@ -63,9 +64,9 @@ namespace OpenRA
 		}
 
 		/// <summary>Returns the minimal region that covers at least the specified cells.</summary>
-		public static CellRegion BoundingRegion(MapGridType shape, IReadOnlyCollection<CPos> cells)
+		public static CellRegion BoundingRegion(MapGridType shape, IEnumerable<CPos> cells)
 		{
-			if (cells == null || cells.Count == 0)
+			if (cells == null || !cells.Any())
 				throw new ArgumentException("cells must not be null or empty.", nameof(cells));
 
 			var minU = int.MaxValue;
@@ -102,7 +103,6 @@ namespace OpenRA
 		}
 
 		public MapCoordsRegion MapCoords => new(mapTopLeft, mapBottomRight);
-		public CellCoordsRegion CellCoords => new(TopLeft, BottomRight);
 
 		public CellRegionEnumerator GetEnumerator()
 		{
@@ -136,12 +136,12 @@ namespace OpenRA
 
 			public bool MoveNext()
 			{
-				u++;
+				u += 1;
 
 				// Check for column overflow
 				if (u > r.mapBottomRight.U)
 				{
-					v++;
+					v += 1;
 					u = r.mapTopLeft.U;
 
 					// Check for row overflow
@@ -162,8 +162,8 @@ namespace OpenRA
 			}
 
 			public CPos Current { get; private set; }
-			readonly object IEnumerator.Current => Current;
-			public readonly void Dispose() { }
+			object IEnumerator.Current => Current;
+			public void Dispose() { }
 		}
 	}
 }

OpenRA.Game/Map/Map.cs

@@ -11,7 +11,6 @@
 
 using System;
 using System.Collections.Generic;
-using System.Collections.Immutable;
 using System.IO;
 using System.Linq;
 using System.Reflection;
@@ -91,13 +90,13 @@ namespace OpenRA
 				throw new InvalidOperationException("Map does not have a field/property " + fieldName);
 
 			var t = field != null ? field.FieldType : property.PropertyType;
-			type = t == typeof(IReadOnlyCollection<MiniYamlNode>) ? Type.NodeList :
+			type = t == typeof(List<MiniYamlNode>) ? Type.NodeList :
 				t == typeof(MiniYaml) ? Type.MiniYaml : Type.Normal;
 		}
 
-		public void Deserialize(Map map, MiniYaml yaml)
+		public void Deserialize(Map map, List<MiniYamlNode> nodes)
 		{
-			var node = yaml.NodeWithKeyOrDefault(key);
+			var node = nodes.FirstOrDefault(n => n.Key == key);
 			if (node == null)
 			{
 				if (required)
@@ -131,14 +130,14 @@ namespace OpenRA
 			var value = field != null ? field.GetValue(map) : property.GetValue(map, null);
 			if (type == Type.NodeList)
 			{
-				var listValue = (IReadOnlyCollection<MiniYamlNode>)value;
+				var listValue = (List<MiniYamlNode>)value;
 				if (required || listValue.Count > 0)
 					nodes.Add(new MiniYamlNode(key, null, listValue));
 			}
 			else if (type == Type.MiniYaml)
 			{
 				var yamlValue = (MiniYaml)value;
-				if (required || (yamlValue != null && (yamlValue.Value != null || yamlValue.Nodes.Length > 0)))
+				if (required || (yamlValue != null && (yamlValue.Value != null || yamlValue.Nodes.Count > 0)))
 					nodes.Add(new MiniYamlNode(key, yamlValue));
 			}
 			else
@@ -159,26 +158,26 @@ namespace OpenRA
 		/// <summary>Defines the order of the fields in map.yaml.</summary>
 		static readonly MapField[] YamlFields =
 		{
-			new("MapFormat"),
-			new("RequiresMod"),
-			new("Title"),
-			new("Author"),
-			new("Tileset"),
-			new("MapSize"),
-			new("Bounds"),
-			new("Visibility"),
-			new("Categories"),
-			new("LockPreview", required: false, ignoreIfValue: "False"),
-			new("Players", "PlayerDefinitions"),
-			new("Actors", "ActorDefinitions"),
-			new("Rules", "RuleDefinitions", required: false),
-			new("Translations", "TranslationDefinitions", required: false),
-			new("Sequences", "SequenceDefinitions", required: false),
-			new("ModelSequences", "ModelSequenceDefinitions", required: false),
-			new("Weapons", "WeaponDefinitions", required: false),
-			new("Voices", "VoiceDefinitions", required: false),
-			new("Music", "MusicDefinitions", required: false),
-			new("Notifications", "NotificationDefinitions", required: false),
+			new MapField("MapFormat"),
+			new MapField("RequiresMod"),
+			new MapField("Title"),
+			new MapField("Author"),
+			new MapField("Tileset"),
+			new MapField("MapSize"),
+			new MapField("Bounds"),
+			new MapField("Visibility"),
+			new MapField("Categories"),
+			new MapField("LockPreview", required: false, ignoreIfValue: "False"),
+			new MapField("Players", "PlayerDefinitions"),
+			new MapField("Actors", "ActorDefinitions"),
+			new MapField("Rules", "RuleDefinitions", required: false),
+			new MapField("Translations", "TranslationDefinitions", required: false),
+			new MapField("Sequences", "SequenceDefinitions", required: false),
+			new MapField("ModelSequences", "ModelSequenceDefinitions", required: false),
+			new MapField("Weapons", "WeaponDefinitions", required: false),
+			new MapField("Voices", "VoiceDefinitions", required: false),
+			new MapField("Music", "MusicDefinitions", required: false),
+			new MapField("Notifications", "NotificationDefinitions", required: false),
 		};
 
 		// Format versions
@@ -198,18 +197,18 @@ namespace OpenRA
 		public int2 MapSize { get; private set; }
 
 		// Player and actor yaml. Public for access by the map importers and lint checks.
-		public IReadOnlyCollection<MiniYamlNode> PlayerDefinitions = ImmutableArray<MiniYamlNode>.Empty;
-		public IReadOnlyCollection<MiniYamlNode> ActorDefinitions = ImmutableArray<MiniYamlNode>.Empty;
+		public List<MiniYamlNode> PlayerDefinitions = new();
+		public List<MiniYamlNode> ActorDefinitions = new();
 
 		// Custom map yaml. Public for access by the map importers and lint checks
-		public MiniYaml RuleDefinitions;
-		public MiniYaml TranslationDefinitions;
-		public MiniYaml SequenceDefinitions;
-		public MiniYaml ModelSequenceDefinitions;
-		public MiniYaml WeaponDefinitions;
-		public MiniYaml VoiceDefinitions;
-		public MiniYaml MusicDefinitions;
-		public MiniYaml NotificationDefinitions;
+		public readonly MiniYaml RuleDefinitions;
+		public readonly MiniYaml TranslationDefinitions;
+		public readonly MiniYaml SequenceDefinitions;
+		public readonly MiniYaml ModelSequenceDefinitions;
+		public readonly MiniYaml WeaponDefinitions;
+		public readonly MiniYaml VoiceDefinitions;
+		public readonly MiniYaml MusicDefinitions;
+		public readonly MiniYaml NotificationDefinitions;
 
 		public readonly Dictionary<CPos, TerrainTile> ReplacedInvalidTerrainTiles = new();
 
@@ -275,10 +274,7 @@ namespace OpenRA
 			try
 			{
 				foreach (var filename in contents)
-					if (filename.EndsWith(".yaml", StringComparison.Ordinal) ||
-						filename.EndsWith(".bin", StringComparison.Ordinal) ||
-						filename.EndsWith(".lua", StringComparison.Ordinal) ||
-						(format >= 12 && filename == "map.png"))
+					if (filename.EndsWith(".yaml") || filename.EndsWith(".bin") || filename.EndsWith(".lua") || (format >= 12 && filename == "map.png"))
 						streams.Add(package.GetStream(filename));
 
 				// Take the SHA1
@@ -361,15 +357,15 @@ namespace OpenRA
 			if (!Package.Contains("map.yaml") || !Package.Contains("map.bin"))
 				throw new InvalidDataException($"Not a valid map\n File: {package.Name}");
 
-			var yaml = new MiniYaml(null, MiniYaml.FromStream(Package.GetStream("map.yaml"), $"{package.Name}:map.yaml"));
+			var yaml = new MiniYaml(null, MiniYaml.FromStream(Package.GetStream("map.yaml"), package.Name));
 			foreach (var field in YamlFields)
-				field.Deserialize(this, yaml);
+				field.Deserialize(this, yaml.Nodes);
 
 			if (MapFormat < SupportedMapFormat)
 				throw new InvalidDataException($"Map format {MapFormat} is not supported.\n File: {package.Name}");
 
-			PlayerDefinitions = yaml.NodeWithKeyOrDefault("Players")?.Value.Nodes ?? ImmutableArray<MiniYamlNode>.Empty;
-			ActorDefinitions = yaml.NodeWithKeyOrDefault("Actors")?.Value.Nodes ?? ImmutableArray<MiniYamlNode>.Empty;
+			PlayerDefinitions = MiniYaml.NodesOrEmpty(yaml, "Players");
+			ActorDefinitions = MiniYaml.NodesOrEmpty(yaml, "Actors");
 
 			Grid = modData.Manifest.Get<MapGrid>();
 
@@ -611,7 +607,7 @@ namespace OpenRA
 
 			// Odd-height ramps get bumped up a level to the next even height layer
 			if ((height & 1) == 1 && Ramp[uv] != 0)
-				height++;
+				height += 1;
 
 			var candidates = new List<PPos>();
 
@@ -650,24 +646,21 @@ namespace OpenRA
 				foreach (var file in Package.Contents)
 					toPackage.Update(file, Package.GetStream(file).ReadAllBytes());
 
-			void UpdatePackage(string filename, byte[] data)
+			if (!LockPreview)
 			{
-				if (Package != toPackage)
-					toPackage.Update(filename, data);
-				else
-				{
-					var stream = Package.GetStream(filename);
-					if (stream == null || !Enumerable.SequenceEqual(data, stream.ReadAllBytes()))
-						toPackage.Update(filename, data);
-				}
+				var previewData = SavePreview();
+				if (Package != toPackage || !Enumerable.SequenceEqual(previewData, Package.GetStream("map.png").ReadAllBytes()))
+					toPackage.Update("map.png", previewData);
 			}
 
-			if (!LockPreview)
-				UpdatePackage("map.png", SavePreview());
-
 			// Update the package with the new map data
-			UpdatePackage("map.yaml", Encoding.UTF8.GetBytes(root.WriteToString()));
-			UpdatePackage("map.bin", SaveBinaryData());
+			var textData = Encoding.UTF8.GetBytes(root.WriteToString());
+			if (Package != toPackage || !Enumerable.SequenceEqual(textData, Package.GetStream("map.yaml").ReadAllBytes()))
+				toPackage.Update("map.yaml", textData);
+
+			var binaryData = SaveBinaryData();
+			if (Package != toPackage || !Enumerable.SequenceEqual(binaryData, Package.GetStream("map.bin").ReadAllBytes()))
+				toPackage.Update("map.bin", binaryData);
 
 			Package = toPackage;
 
@@ -688,16 +681,16 @@ namespace OpenRA
 				writer.Write((ushort)MapSize.Y);
 
 				// Data offsets
-				const int TilesOffset = 17;
+				var tilesOffset = 17;
 				var heightsOffset = Grid.MaximumTerrainHeight > 0 ? 3 * MapSize.X * MapSize.Y + 17 : 0;
 				var resourcesOffset = (Grid.MaximumTerrainHeight > 0 ? 4 : 3) * MapSize.X * MapSize.Y + 17;
 
-				writer.Write((uint)TilesOffset);
+				writer.Write((uint)tilesOffset);
 				writer.Write((uint)heightsOffset);
 				writer.Write((uint)resourcesOffset);
 
 				// Tile data
-				if (TilesOffset != 0)
+				if (tilesOffset != 0)
 				{
 					for (var i = 0; i < MapSize.X; i++)
 					{
@@ -779,10 +772,19 @@ namespace OpenRA
 
 			if (Grid.MaximumTerrainHeight > 0)
 			{
-				(top, bottom) = GetCellSpaceBounds();
+				// The minimap is drawn in cell space, so we need to
+				// unproject the PPos bounds to find the MPos boundaries.
+				// This matches the calculation in RadarWidget that is used ingame
+				for (var x = Bounds.Left; x < Bounds.Right; x++)
+				{
+					var allTop = Unproject(new PPos(x, Bounds.Top));
+					var allBottom = Unproject(new PPos(x, Bounds.Bottom));
+					if (allTop.Count > 0)
+						top = Math.Min(top, allTop.MinBy(uv => uv.V).V);
 
-				if (top == int.MaxValue || bottom == int.MinValue)
-					throw new InvalidDataException("The map has invalid boundaries");
+					if (allBottom.Count > 0)
+						bottom = Math.Max(bottom, allBottom.MaxBy(uv => uv.V).V);
+				}
 			}
 			else
 			{
@@ -799,7 +801,7 @@ namespace OpenRA
 				bitmapWidth = 2 * bitmapWidth - 1;
 
 			var stride = bitmapWidth * 4;
-			const int PxStride = 4;
+			var pxStride = 4;
 			var minimapData = new byte[stride * height];
 			(Color Left, Color Right) terrainColor = default;
 
@@ -821,10 +823,10 @@ namespace OpenRA
 					{
 						// Odd rows are shifted right by 1px
 						var dx = uv.V & 1;
-						var xOffset = PxStride * (2 * x + dx);
+						var xOffset = pxStride * (2 * x + dx);
 						if (x + dx > 0)
 						{
-							var z = y * stride + xOffset - PxStride;
+							var z = y * stride + xOffset - pxStride;
 							var c = actorColor.A == 0 ? terrainColor.Left : actorColor;
 							minimapData[z++] = c.R;
 							minimapData[z++] = c.G;
@@ -844,7 +846,7 @@ namespace OpenRA
 					}
 					else
 					{
-						var z = y * stride + PxStride * x;
+						var z = y * stride + pxStride * x;
 						var c = actorColor.A == 0 ? terrainColor.Left : actorColor;
 						minimapData[z++] = c.R;
 						minimapData[z++] = c.G;
@@ -858,28 +860,6 @@ namespace OpenRA
 			return png.Save();
 		}
 
-		public (int Top, int Bottom) GetCellSpaceBounds()
-		{
-			var top = int.MaxValue;
-			var bottom = int.MinValue;
-
-			// The minimap is drawn in cell space, so we need to
-			// unproject the PPos bounds to find the MPos boundaries.
-			// This matches the calculation in RadarWidget that is used ingame
-			for (var x = Bounds.Left; x < Bounds.Right; x++)
-			{
-				var allTop = Unproject(new PPos(x, Bounds.Top));
-				var allBottom = Unproject(new PPos(x, Bounds.Bottom));
-				if (allTop.Count > 0)
-					top = Math.Min(top, allTop.MinBy(uv => uv.V).V);
-
-				if (allBottom.Count > 0)
-					bottom = Math.Max(bottom, allBottom.MaxBy(uv => uv.V).V);
-			}
-
-			return (top, bottom);
-		}
-
 		public bool Contains(CPos cell)
 		{
 			if (Grid.Type == MapGridType.RectangularIsometric)
@@ -1200,7 +1180,7 @@ namespace OpenRA
 			// Project this guessed cell and take the first available cell
 			// If it is projected outside the layer, then make another guess.
 			var allProjected = ProjectedCellsCovering(uv);
-			var projected = allProjected.Length > 0 ? allProjected[0]
+			var projected = allProjected.Length > 0 ? allProjected.First()
 				: new PPos(uv.U, uv.V.Clamp(Bounds.Top, Bounds.Bottom));
 
 			// Clamp the projected cell to the map area
@@ -1269,7 +1249,7 @@ namespace OpenRA
 			PPos edge;
 			if (allProjected.Length > 0)
 			{
-				var puv = allProjected[0];
+				var puv = allProjected.First();
 				var horizontalBound = (puv.U - Bounds.Left < Bounds.Width / 2) ? Bounds.Left : Bounds.Right;
 				var verticalBound = (puv.V - Bounds.Top < Bounds.Height / 2) ? Bounds.Top : Bounds.Bottom;
 
@@ -1369,18 +1349,13 @@ namespace OpenRA
 				throw new ArgumentOutOfRangeException(nameof(maxRange),
 					$"The requested range ({maxRange}) cannot exceed the value of MaximumTileSearchRange ({Grid.MaximumTileSearchRange})");
 
-			return FindTilesInAnnulus();
-
-			IEnumerable<CPos> FindTilesInAnnulus()
+			for (var i = minRange; i <= maxRange; i++)
 			{
-				for (var i = minRange; i <= maxRange; i++)
+				foreach (var offset in Grid.TilesByDistance[i])
 				{
-					foreach (var offset in Grid.TilesByDistance[i])
-					{
-						var t = offset + center;
-						if (allowOutsideBounds ? Tiles.Contains(t) : Contains(t))
-							yield return t;
-					}
+					var t = offset + center;
+					if (allowOutsideBounds ? Tiles.Contains(t) : Contains(t))
+						yield return t;
 				}
 			}
 		}

OpenRA.Game/Map/MapCache.cs

@@ -38,7 +38,7 @@ namespace OpenRA
 		readonly object syncRoot = new();
 		readonly Queue<MapPreview> generateMinimap = new();
 
-		public HashSet<string> StringPool { get; } = new();
+		public Dictionary<string, string> StringPool { get; } = new Dictionary<string, string>();
 
 		readonly List<MapDirectoryTracker> mapDirectoryTrackers = new();
 
@@ -97,7 +97,7 @@ namespace OpenRA
 					? MapClassification.Unknown : Enum<MapClassification>.Parse(kv.Value);
 
 				IReadOnlyPackage package;
-				var optional = name.StartsWith('~');
+				var optional = name.StartsWith("~", StringComparison.Ordinal);
 				if (optional)
 					name = name[1..];
 
@@ -106,7 +106,7 @@ namespace OpenRA
 					// HACK: If the path is inside the support directory then we may need to create it
 					// Assume that the path is a directory if there is not an existing file with the same name
 					var resolved = Platform.ResolvePath(name);
-					if (resolved.StartsWith(Platform.SupportDir, StringComparison.Ordinal) && !File.Exists(resolved))
+					if (resolved.StartsWith(Platform.SupportDir) && !File.Exists(resolved))
 						Directory.CreateDirectory(resolved);
 
 					package = modData.ModFiles.OpenPackage(name);
@@ -128,10 +128,7 @@ namespace OpenRA
 			foreach (var kv in MapLocations)
 			{
 				foreach (var map in kv.Key.Contents)
-				{
 					LoadMapInternal(map, kv.Key, kv.Value, mapGrid, null, modDataRules);
-					GC.Collect();
-				}
 			}
 
 			// We only want to track maps in runtime, not at loadtime
@@ -151,16 +148,11 @@ namespace OpenRA
 				using (new PerfTimer(map))
 				{
 					mapPackage = package.OpenPackage(map, modData.ModFiles);
-					Log.Write("debug", $"Loading Map: {map} FROM {mapPackage.Name}");
-					Console.WriteLine($"Loading Map: {map} FROM {mapPackage.Name}");
 					if (mapPackage != null)
 					{
 						var uid = Map.ComputeUID(mapPackage);
 						previews[uid].UpdateFromMap(mapPackage, package, classification, modData.Manifest.MapCompatibility, mapGrid.Type, modDataRules);
 
-						// Freeing the package to save memory if there is a lot of Maps
-						previews[uid].PackageDispose();
-
 						if (oldMap != uid)
 						{
 							LastModifiedMap = uid;
@@ -176,13 +168,9 @@ namespace OpenRA
 				Console.WriteLine($"Failed to load map: {map}");
 				Console.WriteLine("Details:");
 				Console.WriteLine(e);
-				Console.WriteLine("StackTrace:");
-				Console.WriteLine(System.Environment.StackTrace);
 				Log.Write("debug", $"Failed to load map: {map}");
 				Log.Write("debug", "Details:");
 				Log.Write("debug", e);
-				Log.Write("debug", "StackTrace:");
-				Log.Write("debug", System.Environment.StackTrace);
 			}
 		}
 
@@ -202,13 +190,13 @@ namespace OpenRA
 					continue;
 
 				var name = kv.Key;
-				var optional = name.StartsWith('~');
+				var optional = name.StartsWith("~", StringComparison.Ordinal);
 				if (optional)
 					name = name[1..];
 
 				// Don't try to open the map directory in the support directory if it doesn't exist
 				var resolved = Platform.ResolvePath(name);
-				if (resolved.StartsWith(Platform.SupportDir, StringComparison.Ordinal) && (!Directory.Exists(resolved) || !File.Exists(resolved)))
+				if (resolved.StartsWith(Platform.SupportDir) && (!Directory.Exists(resolved) || !File.Exists(resolved)))
 					continue;
 
 				using (var package = (IReadWritePackage)modData.ModFiles.OpenPackage(name))
@@ -245,12 +233,11 @@ namespace OpenRA
 				.ToList();
 
 			foreach (var uid in queryUids)
-				previews[uid].UpdateRemoteSearch(MapStatus.Searching, null, null);
+				previews[uid].UpdateRemoteSearch(MapStatus.Searching, null);
 
 			Task.Run(async () =>
 			{
 				var client = HttpClientFactory.Create();
-				var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 
 				// Limit each query to 50 maps at a time to avoid request size limits
 				for (var i = 0; i < queryUids.Count; i += 50)
@@ -262,15 +249,15 @@ namespace OpenRA
 						var httpResponseMessage = await client.GetAsync(url);
 						var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-						var yaml = MiniYaml.FromStream(result, url, stringPool: stringPool);
+						var yaml = MiniYaml.FromStream(result);
 						foreach (var kv in yaml)
-							previews[kv.Key].UpdateRemoteSearch(MapStatus.DownloadAvailable, kv.Value, modData.Manifest.MapCompatibility, mapDetailsReceived);
+							previews[kv.Key].UpdateRemoteSearch(MapStatus.DownloadAvailable, kv.Value, mapDetailsReceived);
 
 						foreach (var uid in batchUids)
 						{
 							var p = previews[uid];
 							if (p.Status != MapStatus.DownloadAvailable)
-								p.UpdateRemoteSearch(MapStatus.Unavailable, null, null);
+								p.UpdateRemoteSearch(MapStatus.Unavailable, null);
 						}
 					}
 					catch (Exception e)
@@ -282,7 +269,7 @@ namespace OpenRA
 						foreach (var uid in batchUids)
 						{
 							var p = previews[uid];
-							p.UpdateRemoteSearch(MapStatus.Unavailable, null, null);
+							p.UpdateRemoteSearch(MapStatus.Unavailable, null);
 							mapQueryFailed?.Invoke(p);
 						}
 					}
@@ -295,11 +282,11 @@ namespace OpenRA
 			Log.Write("debug", "MapCache.LoadAsyncInternal started");
 
 			// Milliseconds to wait on one loop when nothing to do
-			const int EmptyDelay = 50;
+			var emptyDelay = 50;
 
 			// Keep the thread alive for at least 5 seconds after the last minimap generation
-			const int MaxKeepAlive = 5000 / EmptyDelay;
-			var keepAlive = MaxKeepAlive;
+			var maxKeepAlive = 5000 / emptyDelay;
+			var keepAlive = maxKeepAlive;
 
 			while (true)
 			{
@@ -319,11 +306,11 @@ namespace OpenRA
 
 				if (todo.Count == 0)
 				{
-					Thread.Sleep(EmptyDelay);
+					Thread.Sleep(emptyDelay);
 					continue;
 				}
 				else
-					keepAlive = MaxKeepAlive;
+					keepAlive = maxKeepAlive;
 
 				// Render the minimap into the shared sheet
 				foreach (var p in todo)
@@ -361,8 +348,8 @@ namespace OpenRA
 
 			while (this[uid].Status != MapStatus.Available)
 			{
-				if (mapUpdates.TryGetValue(uid, out var newUid))
-					uid = newUid;
+				if (mapUpdates.ContainsKey(uid))
+					uid = mapUpdates[uid];
 				else
 					return null;
 			}
@@ -385,6 +372,7 @@ namespace OpenRA
 				{
 					// Wait for any existing thread to exit before starting a new one.
 					previewLoaderThread?.Join();
+
 					previewLoaderThread = new Thread(LoadAsyncInternal)
 					{
 						Name = "Map Preview Loader",

OpenRA.Game/Map/MapCoordsRegion.cs

@@ -35,7 +35,7 @@ namespace OpenRA
 				// Check for column overflow
 				if (u > r.BottomRight.U)
 				{
-					v++;
+					v += 1;
 					u = r.TopLeft.U;
 
 					// Check for row overflow
@@ -53,8 +53,8 @@ namespace OpenRA
 			}
 
 			public MPos Current { get; private set; }
-			readonly object IEnumerator.Current => Current;
-			public readonly void Dispose() { }
+			object IEnumerator.Current => Current;
+			public void Dispose() { }
 		}
 
 		public MapCoordsRegion(MPos mapTopLeft, MPos mapBottomRight)

OpenRA.Game/Map/MapGrid.cs

@@ -116,12 +116,12 @@ namespace OpenRA
 
 		public readonly WVec[] SubCellOffsets =
 		{
-			new(0, 0, 0),       // full cell - index 0
-			new(-299, -256, 0), // top left - index 1
-			new(256, -256, 0),  // top right - index 2
-			new(0, 0, 0),       // center - index 3
-			new(-299, 256, 0),  // bottom left - index 4
-			new(256, 256, 0),   // bottom right - index 5
+			new WVec(0, 0, 0),       // full cell - index 0
+			new WVec(-299, -256, 0), // top left - index 1
+			new WVec(256, -256, 0),  // top right - index 2
+			new WVec(0, 0, 0),       // center - index 3
+			new WVec(-299, 256, 0),  // bottom left - index 4
+			new WVec(256, 256, 0),   // bottom right - index 5
 		};
 
 		public CellRamp[] Ramps { get; }

OpenRA.Game/Map/MapPreview.cs

@@ -59,7 +59,6 @@ namespace OpenRA
 		public readonly string rules;
 		public readonly string players_block;
 		public readonly int mapformat;
-		public readonly string game_mod;
 	}
 
 	public sealed class MapPreview : IDisposable, IReadOnlyFileSystem
@@ -140,11 +139,10 @@ namespace OpenRA
 							files = files.Append(mapFiles);
 						}
 
-						var stringPool = new HashSet<string>(); // Reuse common strings in YAML
 						var sources =
 							modDataRules.Select(x => x.Where(IsLoadableRuleDefinition).ToList())
-							.Concat(files.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s, stringPool: stringPool).Where(IsLoadableRuleDefinition).ToList()));
-						if (RuleDefinitions.Nodes.Length > 0)
+							.Concat(files.Select(s => MiniYaml.FromStream(fileSystem.Open(s), s).Where(IsLoadableRuleDefinition).ToList()));
+						if (RuleDefinitions.Nodes.Count > 0)
 							sources = sources.Append(RuleDefinitions.Nodes.Where(IsLoadableRuleDefinition).ToList());
 
 						var yamlNodes = MiniYaml.Merge(sources);
@@ -174,23 +172,7 @@ namespace OpenRA
 		readonly ModData modData;
 
 		public readonly string Uid;
-		public string PackageName { get; private set; }
-		IReadOnlyPackage pPackage;
-		public IReadOnlyPackage Package
-		{
-			get
-			{
-				if (pPackage == null)
-				{
-					pPackage = parentPackage.OpenPackage(PackageName, modData.ModFiles);
-				}
-
-				return pPackage;
-			}
-
-			private set => pPackage = value;
-		}
-
+		public IReadOnlyPackage Package { get; private set; }
 		IReadOnlyPackage parentPackage;
 
 		volatile InnerData innerData;
@@ -274,7 +256,6 @@ namespace OpenRA
 		{
 			this.cache = cache;
 			this.modData = modData;
-			this.pPackage = null;
 
 			Uid = uid;
 			innerData = new InnerData
@@ -301,10 +282,9 @@ namespace OpenRA
 		{
 			this.modData = modData;
 			cache = modData.MapCache;
-			this.pPackage = null;
 
 			Uid = map.Uid;
-			PackageName = map.Package.Name;
+			Package = map.Package;
 
 			var mapPlayers = new MapPlayers(map.PlayerDefinitions);
 			var spawns = new List<CPos>();
@@ -353,10 +333,10 @@ namespace OpenRA
 				if (yamlStream == null)
 					throw new FileNotFoundException("Required file map.yaml not present in this map");
 
-				yaml = new MiniYaml(null, MiniYaml.FromStream(yamlStream, $"{p.Name}:map.yaml", stringPool: cache.StringPool)).ToDictionary();
+				yaml = new MiniYaml(null, MiniYaml.FromStream(yamlStream, "map.yaml", stringPool: cache.StringPool)).ToDictionary();
 			}
 
-			PackageName = p.Name;
+			Package = p;
 			parentPackage = parent;
 
 			var newData = innerData.Clone();
@@ -447,7 +427,7 @@ namespace OpenRA
 			innerData = newData;
 		}
 
-		public void UpdateRemoteSearch(MapStatus status, MiniYaml yaml, string[] mapCompatibility, Action<MapPreview> parseMetadata = null)
+		public void UpdateRemoteSearch(MapStatus status, MiniYaml yaml, Action<MapPreview> parseMetadata = null)
 		{
 			var newData = innerData.Clone();
 			newData.Status = status;
@@ -494,19 +474,11 @@ namespace OpenRA
 					}
 
 					var playersString = Encoding.UTF8.GetString(Convert.FromBase64String(r.players_block));
-					newData.Players = new MapPlayers(MiniYaml.FromString(playersString,
-						$"{yaml.NodeWithKey(nameof(r.players_block)).Location.Name}:{nameof(r.players_block)}"));
+					newData.Players = new MapPlayers(MiniYaml.FromString(playersString));
 
 					var rulesString = Encoding.UTF8.GetString(Convert.FromBase64String(r.rules));
-					var rulesYaml = new MiniYaml("", MiniYaml.FromString(rulesString,
-						$"{yaml.NodeWithKey(nameof(r.rules)).Location.Name}:{nameof(r.rules)}")).ToDictionary();
+					var rulesYaml = new MiniYaml("", MiniYaml.FromString(rulesString)).ToDictionary();
 					newData.SetCustomRules(modData, this, rulesYaml, null);
-
-					// Map is for a different mod: update its information so it can be displayed
-					// in the cross-mod server browser UI, but mark it as unavailable so it can't
-					// be selected in a server for the current mod.
-					if (!mapCompatibility.Contains(r.game_mod))
-						newData.Status = MapStatus.Unavailable;
 				}
 				catch (Exception e)
 				{
@@ -605,15 +577,10 @@ namespace OpenRA
 
 		public void Dispose()
 		{
-			PackageDispose();
-		}
-
-		public void PackageDispose()
-		{
-			if (pPackage != null)
+			if (Package != null)
 			{
-				pPackage.Dispose();
-				pPackage = null;
+				Package.Dispose();
+				Package = null;
 			}
 		}
 

OpenRA.Game/Map/ProjectedCellLayer.cs

@@ -9,7 +9,6 @@
  */
 #endregion
 
-using System;
 using OpenRA.Primitives;
 
 namespace OpenRA
@@ -54,15 +53,5 @@ namespace OpenRA
 		{
 			return Bounds.Contains(uv.U, uv.V);
 		}
-
-		public int IndexOf(T value, int startIndex)
-		{
-			return Array.IndexOf(Entries, value, startIndex);
-		}
-
-		public void SetAll(T value)
-		{
-			Array.Fill(Entries, value);
-		}
 	}
 }

OpenRA.Game/Map/ProjectedCellRegion.cs

@@ -93,12 +93,12 @@ namespace OpenRA
 
 			public bool MoveNext()
 			{
-				u++;
+				u += 1;
 
 				// Check for column overflow
 				if (u > r.BottomRight.U)
 				{
-					v++;
+					v += 1;
 					u = r.TopLeft.U;
 
 					// Check for row overflow
@@ -118,8 +118,8 @@ namespace OpenRA
 			}
 
 			public PPos Current { get; private set; }
-			readonly object IEnumerator.Current => Current;
-			public readonly void Dispose() { }
+			object IEnumerator.Current => Current;
+			public void Dispose() { }
 		}
 	}
 }

OpenRA.Game/MiniYaml.cs

@@ -20,36 +20,18 @@ namespace OpenRA
 {
 	public static class MiniYamlExts
 	{
-		public static void WriteToFile(this IEnumerable<MiniYamlNode> y, string filename)
+		public static void WriteToFile(this List<MiniYamlNode> y, string filename)
 		{
 			File.WriteAllLines(filename, y.ToLines().Select(x => x.TrimEnd()).ToArray());
 		}
 
-		public static string WriteToString(this IEnumerable<MiniYamlNode> y)
+		public static string WriteToString(this List<MiniYamlNode> y)
 		{
 			// Remove all trailing newlines and restore the final EOF newline
 			return y.ToLines().JoinWith("\n").TrimEnd('\n') + "\n";
 		}
 
-		public static IEnumerable<string> ToLines(this IEnumerable<MiniYamlNode> y)
-		{
-			foreach (var kv in y)
-				foreach (var line in kv.Value.ToLines(kv.Key, kv.Comment))
-					yield return line;
-		}
-
-		public static void WriteToFile(this IEnumerable<MiniYamlNodeBuilder> y, string filename)
-		{
-			File.WriteAllLines(filename, y.ToLines().Select(x => x.TrimEnd()).ToArray());
-		}
-
-		public static string WriteToString(this IEnumerable<MiniYamlNodeBuilder> y)
-		{
-			// Remove all trailing newlines and restore the final EOF newline
-			return y.ToLines().JoinWith("\n").TrimEnd('\n') + "\n";
-		}
-
-		public static IEnumerable<string> ToLines(this IEnumerable<MiniYamlNodeBuilder> y)
+		public static IEnumerable<string> ToLines(this List<MiniYamlNode> y)
 		{
 			foreach (var kv in y)
 				foreach (var line in kv.Value.ToLines(kv.Key, kv.Comment))
@@ -61,29 +43,22 @@ namespace OpenRA
 	{
 		public readonly struct SourceLocation
 		{
-			public readonly string Name;
+			public readonly string Filename;
 			public readonly int Line;
 
-			public SourceLocation(string name, int line)
+			public SourceLocation(string filename, int line)
 			{
-				Name = name;
+				Filename = filename;
 				Line = line;
 			}
 
-			public override string ToString() { return $"{Name}:{Line}"; }
+			public override string ToString() { return $"{Filename}:{Line}"; }
 		}
 
-		public readonly SourceLocation Location;
-		public readonly string Key;
-		public readonly MiniYaml Value;
-		public readonly string Comment;
-
-		public MiniYamlNode WithValue(MiniYaml value)
-		{
-			if (Value == value)
-				return this;
-			return new MiniYamlNode(Key, value, Comment, Location);
-		}
+		public SourceLocation Location;
+		public string Key;
+		public MiniYaml Value;
+		public string Comment;
 
 		public MiniYamlNode(string k, MiniYaml v, string c = null)
 		{
@@ -99,15 +74,26 @@ namespace OpenRA
 		}
 
 		public MiniYamlNode(string k, string v, string c = null)
-			: this(k, new MiniYaml(v, Enumerable.Empty<MiniYamlNode>()), c) { }
+			: this(k, v, c, null) { }
 
-		public MiniYamlNode(string k, string v, IEnumerable<MiniYamlNode> n)
+		public MiniYamlNode(string k, string v, List<MiniYamlNode> n)
 			: this(k, new MiniYaml(v, n), null) { }
 
+		public MiniYamlNode(string k, string v, string c, List<MiniYamlNode> n)
+			: this(k, new MiniYaml(v, n), c) { }
+
+		public MiniYamlNode(string k, string v, string c, List<MiniYamlNode> n, SourceLocation loc)
+			: this(k, new MiniYaml(v, n), c, loc) { }
+
 		public override string ToString()
 		{
 			return $"{{YamlNode: {Key} @ {Location}}}";
 		}
+
+		public MiniYamlNode Clone()
+		{
+			return new MiniYamlNode(Key, Value.Clone(), Comment, Location);
+		}
 	}
 
 	public sealed class MiniYaml
@@ -115,58 +101,15 @@ namespace OpenRA
 		const int SpacesPerLevel = 4;
 		static readonly Func<string, string> StringIdentity = s => s;
 		static readonly Func<MiniYaml, MiniYaml> MiniYamlIdentity = my => my;
+		public string Value;
+		public List<MiniYamlNode> Nodes;
 
-		public readonly string Value;
-		public readonly ImmutableArray<MiniYamlNode> Nodes;
-
-		public MiniYaml WithValue(string value)
+		public MiniYaml Clone()
 		{
-			if (Value == value)
-				return this;
-			return new MiniYaml(value, Nodes);
-		}
-
-		public MiniYaml WithNodes(IEnumerable<MiniYamlNode> nodes)
-		{
-			if (nodes is ImmutableArray<MiniYamlNode> n && Nodes == n)
-				return this;
-			return new MiniYaml(Value, nodes);
-		}
-
-		public MiniYaml WithNodesAppended(IEnumerable<MiniYamlNode> nodes)
-		{
-			var newNodes = Nodes.AddRange(nodes);
-			if (Nodes == newNodes)
-				return this;
-			return new MiniYaml(Value, newNodes);
-		}
-
-		public MiniYamlNode NodeWithKey(string key)
-		{
-			var result = NodeWithKeyOrDefault(key);
-			if (result == null)
-				throw new InvalidDataException($"No node with key '{key}'");
-			return result;
-		}
-
-		public MiniYamlNode NodeWithKeyOrDefault(string key)
-		{
-			// PERF: Avoid LINQ.
-			var first = true;
-			MiniYamlNode result = null;
+			var clonedNodes = new List<MiniYamlNode>(Nodes.Count);
 			foreach (var node in Nodes)
-			{
-				if (node.Key != key)
-					continue;
-
-				if (!first)
-					throw new InvalidDataException($"Duplicate key '{node.Key}' in {node.Location}");
-
-				first = false;
-				result = node;
-			}
-
-			return result;
+				clonedNodes.Add(node.Clone());
+			return new MiniYaml(Value, clonedNodes);
 		}
 
 		public Dictionary<string, MiniYaml> ToDictionary()
@@ -182,7 +125,7 @@ namespace OpenRA
 		public Dictionary<TKey, TElement> ToDictionary<TKey, TElement>(
 			Func<string, TKey> keySelector, Func<MiniYaml, TElement> elementSelector)
 		{
-			var ret = new Dictionary<TKey, TElement>(Nodes.Length);
+			var ret = new Dictionary<TKey, TElement>(Nodes.Count);
 			foreach (var y in Nodes)
 			{
 				var key = keySelector(y.Key);
@@ -195,27 +138,28 @@ namespace OpenRA
 		}
 
 		public MiniYaml(string value)
-			: this(value, Enumerable.Empty<MiniYamlNode>()) { }
+			: this(value, null) { }
 
-		public MiniYaml(string value, IEnumerable<MiniYamlNode> nodes)
+		public MiniYaml(string value, List<MiniYamlNode> nodes)
 		{
 			Value = value;
-			Nodes = ImmutableArray.CreateRange(nodes);
+			Nodes = nodes ?? new List<MiniYamlNode>();
 		}
 
-		static List<MiniYamlNode> FromLines(IEnumerable<ReadOnlyMemory<char>> lines, string name, bool discardCommentsAndWhitespace, HashSet<string> stringPool)
+		public static List<MiniYamlNode> NodesOrEmpty(MiniYaml y, string s)
 		{
-			// YAML config often contains repeated strings for key, values, comments.
-			// Pool these strings so we only need one copy of each unique string.
-			// This saves on long-term memory usage as parsed values can often live a long time.
-			// A caller can also provide a pool as input, allowing de-duplication across multiple parses.
-			stringPool ??= new HashSet<string>();
+			var nd = y.ToDictionary();
+			return nd.TryGetValue(s, out var v) ? v.Nodes : new List<MiniYamlNode>();
+		}
 
-			var result = new List<List<MiniYamlNode>>
+		static List<MiniYamlNode> FromLines(IEnumerable<ReadOnlyMemory<char>> lines, string filename, bool discardCommentsAndWhitespace, Dictionary<string, string> stringPool)
+		{
+			stringPool ??= new Dictionary<string, string>();
+
+			var levels = new List<List<MiniYamlNode>>
 			{
-				new()
+				new List<MiniYamlNode>()
 			};
-			var parsedLines = new List<(int Level, string Key, string Value, string Comment, MiniYamlNode.SourceLocation Location)>();
 
 			var lineNo = 0;
 			foreach (var ll in lines)
@@ -231,7 +175,7 @@ namespace OpenRA
 				ReadOnlySpan<char> key = default;
 				ReadOnlySpan<char> value = default;
 				ReadOnlySpan<char> comment = default;
-				var location = new MiniYamlNode.SourceLocation(name, lineNo);
+				var location = new MiniYamlNode.SourceLocation(filename, lineNo);
 
 				if (line.Length > 0)
 				{
@@ -262,6 +206,15 @@ namespace OpenRA
 						}
 					}
 
+					if (levels.Count <= level)
+						throw new YamlException($"Bad indent in miniyaml at {location}");
+
+					while (levels.Count > level + 1)
+					{
+						levels[^1].TrimExcess();
+						levels.RemoveAt(levels.Count - 1);
+					}
+
 					// Extract key, value, comment from line as `<key>: <value>#<comment>`
 					// The # character is allowed in the value if escaped (\#).
 					// Leading and trailing whitespace is always trimmed from keys.
@@ -283,7 +236,7 @@ namespace OpenRA
 						if (commentStart < 0 && line[i] == '#' && (i == 0 || line[i - 1] != '\\'))
 						{
 							commentStart = i + 1;
-							if (i <= keyStart + keyLength)
+							if (commentStart <= keyLength)
 								keyLength = i - keyStart;
 							else
 								valueLength = i - valueStart;
@@ -321,12 +274,6 @@ namespace OpenRA
 
 				if (!key.IsEmpty || !discardCommentsAndWhitespace)
 				{
-					if (parsedLines.Count > 0 && parsedLines[^1].Level < level - 1)
-						throw new YamlException($"Bad indent in miniyaml at {location}");
-
-					while (parsedLines.Count > 0 && parsedLines[^1].Level > level)
-						BuildCompletedSubNode(level);
-
 					var keyString = key.IsEmpty ? null : key.ToString();
 					var valueString = value.IsEmpty ? null : value.ToString();
 
@@ -334,68 +281,39 @@ namespace OpenRA
 					// (i.e. a lone # at the end of a line) can be correctly re-serialized
 					var commentString = comment == default ? null : comment.ToString();
 
-					keyString = keyString == null ? null : stringPool.GetOrAdd(keyString);
-					valueString = valueString == null ? null : stringPool.GetOrAdd(valueString);
-					commentString = commentString == null ? null : stringPool.GetOrAdd(commentString);
+					keyString = keyString == null ? null : stringPool.GetOrAdd(keyString, keyString);
+					valueString = valueString == null ? null : stringPool.GetOrAdd(valueString, valueString);
+					commentString = commentString == null ? null : stringPool.GetOrAdd(commentString, commentString);
 
-					parsedLines.Add((level, keyString, valueString, commentString, location));
+					var nodes = new List<MiniYamlNode>();
+					levels[level].Add(new MiniYamlNode(keyString, valueString, commentString, nodes, location));
+
+					levels.Add(nodes);
 				}
 			}
 
-			if (parsedLines.Count > 0)
-				BuildCompletedSubNode(0);
+			foreach (var nodes in levels)
+				nodes.TrimExcess();
 
-			return result[0];
-
-			void BuildCompletedSubNode(int level)
-			{
-				var lastLevel = parsedLines[^1].Level;
-				while (lastLevel >= result.Count)
-					result.Add(new List<MiniYamlNode>());
-
-				while (parsedLines.Count > 0 && parsedLines[^1].Level >= level)
-				{
-					var parent = parsedLines[^1];
-					var startOfRange = parsedLines.Count - 1;
-					while (startOfRange > 0 && parsedLines[startOfRange - 1].Level == parent.Level)
-						startOfRange--;
-
-					for (var i = startOfRange; i < parsedLines.Count - 1; i++)
-					{
-						var sibling = parsedLines[i];
-						result[parent.Level].Add(
-							new MiniYamlNode(sibling.Key, new MiniYaml(sibling.Value), sibling.Comment, sibling.Location));
-					}
-
-					var childNodes = parent.Level + 1 < result.Count ? result[parent.Level + 1] : null;
-					result[parent.Level].Add(new MiniYamlNode(
-						parent.Key,
-						new MiniYaml(parent.Value, childNodes ?? Enumerable.Empty<MiniYamlNode>()),
-						parent.Comment,
-						parent.Location));
-					childNodes?.Clear();
-
-					parsedLines.RemoveRange(startOfRange, parsedLines.Count - startOfRange);
-				}
-			}
+			return levels[0];
 		}
 
-		public static List<MiniYamlNode> FromFile(string path, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
+		public static List<MiniYamlNode> FromFile(string path, bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
 		{
 			return FromStream(File.OpenRead(path), path, discardCommentsAndWhitespace, stringPool);
 		}
 
-		public static List<MiniYamlNode> FromStream(Stream s, string name, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
+		public static List<MiniYamlNode> FromStream(Stream s, string fileName = "<no filename available>", bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
 		{
-			return FromLines(s.ReadAllLinesAsMemory(), name, discardCommentsAndWhitespace, stringPool);
+			return FromLines(s.ReadAllLinesAsMemory(), fileName, discardCommentsAndWhitespace, stringPool);
 		}
 
-		public static List<MiniYamlNode> FromString(string text, string name, bool discardCommentsAndWhitespace = true, HashSet<string> stringPool = null)
+		public static List<MiniYamlNode> FromString(string text, string fileName = "<no filename available>", bool discardCommentsAndWhitespace = true, Dictionary<string, string> stringPool = null)
 		{
-			return FromLines(text.Split(new[] { "\r\n", "\n" }, StringSplitOptions.None).Select(s => s.AsMemory()), name, discardCommentsAndWhitespace, stringPool);
+			return FromLines(text.Split(new[] { "\r\n", "\n" }, StringSplitOptions.None).Select(s => s.AsMemory()), fileName, discardCommentsAndWhitespace, stringPool);
 		}
 
-		public static List<MiniYamlNode> Merge(IEnumerable<IReadOnlyCollection<MiniYamlNode>> sources)
+		public static List<MiniYamlNode> Merge(IEnumerable<List<MiniYamlNode>> sources)
 		{
 			var sourcesList = sources.ToList();
 			if (sourcesList.Count == 0)
@@ -418,7 +336,7 @@ namespace OpenRA
 			}
 
 			// Resolve any top-level removals (e.g. removing whole actor blocks)
-			var nodes = new MiniYaml("", resolved.Select(kv => new MiniYamlNode(kv.Key, kv.Value)));
+			var nodes = new MiniYaml("", resolved.Select(kv => new MiniYamlNode(kv.Key, kv.Value)).ToList());
 			return ResolveInherits(nodes, tree, ImmutableDictionary<string, MiniYamlNode.SourceLocation>.Empty);
 		}
 
@@ -427,23 +345,19 @@ namespace OpenRA
 		{
 			if (existingNodeKeys.Add(overrideNode.Key))
 			{
-				existingNodes.Add(overrideNode);
+				existingNodes.Add(overrideNode.Clone());
 				return;
 			}
 
-			var existingNodeIndex = IndexOfKey(existingNodes, overrideNode.Key);
-			var existingNode = existingNodes[existingNodeIndex];
-			var value = MergePartial(existingNode.Value, overrideNode.Value);
-			var nodes = ResolveInherits(value, tree, inherited);
-			if (!value.Nodes.SequenceEqual(nodes))
-				value = value.WithNodes(nodes);
-			existingNodes[existingNodeIndex] = existingNode.WithValue(value);
+			var existingNode = existingNodes.Find(n => n.Key == overrideNode.Key);
+			existingNode.Value = MergePartial(existingNode.Value, overrideNode.Value);
+			existingNode.Value.Nodes = ResolveInherits(existingNode.Value, tree, inherited);
 		}
 
 		static List<MiniYamlNode> ResolveInherits(MiniYaml node, Dictionary<string, MiniYaml> tree, ImmutableDictionary<string, MiniYamlNode.SourceLocation> inherited)
 		{
-			var resolved = new List<MiniYamlNode>(node.Nodes.Length);
-			var resolvedKeys = new HashSet<string>(node.Nodes.Length);
+			var resolved = new List<MiniYamlNode>(node.Nodes.Count);
+			var resolvedKeys = new HashSet<string>(node.Nodes.Count);
 
 			foreach (var n in node.Nodes)
 			{
@@ -465,7 +379,7 @@ namespace OpenRA
 					foreach (var r in ResolveInherits(parent, tree, inherited))
 						MergeIntoResolved(r, resolved, resolvedKeys, tree, inherited);
 				}
-				else if (n.Key.StartsWith('-'))
+				else if (n.Key.StartsWith("-", StringComparison.Ordinal))
 				{
 					var removed = n.Key[1..];
 					if (resolved.RemoveAll(r => r.Key == removed) == 0)
@@ -476,6 +390,7 @@ namespace OpenRA
 					MergeIntoResolved(n, resolved, resolvedKeys, tree, inherited);
 			}
 
+			resolved.TrimExcess();
 			return resolved;
 		}
 
@@ -483,7 +398,7 @@ namespace OpenRA
 		/// Merges any duplicate keys that are defined within the same set of nodes.
 		/// Does not resolve inheritance or node removals.
 		/// </summary>
-		static IReadOnlyCollection<MiniYamlNode> MergeSelfPartial(IReadOnlyCollection<MiniYamlNode> existingNodes)
+		static List<MiniYamlNode> MergeSelfPartial(List<MiniYamlNode> existingNodes)
 		{
 			var keys = new HashSet<string>(existingNodes.Count);
 			var ret = new List<MiniYamlNode>(existingNodes.Count);
@@ -494,12 +409,12 @@ namespace OpenRA
 				else
 				{
 					// Node with the same key has already been added: merge new node over the existing one
-					var originalIndex = IndexOfKey(ret, n.Key);
-					var original = ret[originalIndex];
-					ret[originalIndex] = original.WithValue(MergePartial(original.Value, n.Value));
+					var original = ret.First(r => r.Key == n.Key);
+					original.Value = MergePartial(original.Value, n.Value);
 				}
 			}
 
+			ret.TrimExcess();
 			return ret;
 		}
 
@@ -517,7 +432,7 @@ namespace OpenRA
 			return new MiniYaml(overrideNodes.Value ?? existingNodes.Value, MergePartial(existingNodes.Nodes, overrideNodes.Nodes));
 		}
 
-		static IReadOnlyCollection<MiniYamlNode> MergePartial(IReadOnlyCollection<MiniYamlNode> existingNodes, IReadOnlyCollection<MiniYamlNode> overrideNodes)
+		static List<MiniYamlNode> MergePartial(List<MiniYamlNode> existingNodes, List<MiniYamlNode> overrideNodes)
 		{
 			if (existingNodes.Count == 0)
 				return overrideNodes;
@@ -537,7 +452,7 @@ namespace OpenRA
 			{
 				// Append Removal nodes to the result.
 				// Therefore: we know the remainder of the method deals with a plain node.
-				if (node.Key.StartsWith('-'))
+				if (node.Key.StartsWith("-", StringComparison.Ordinal))
 				{
 					ret.Add(node);
 					return;
@@ -553,8 +468,9 @@ namespace OpenRA
 				// A Removal node is closer than the previous node.
 				// We should not merge the new node, as the data being merged will jump before the Removal.
 				// Instead, append it so the previous node is applied, then removed, then the new node is applied.
-				var previousNodeIndex = LastIndexOfKey(ret, node.Key);
-				var previousRemovalNodeIndex = LastIndexOfKey(ret, $"-{node.Key}");
+				var removalKey = $"-{node.Key}";
+				var previousNodeIndex = ret.FindLastIndex(n => n.Key == node.Key);
+				var previousRemovalNodeIndex = ret.FindLastIndex(n => n.Key == removalKey);
 				if (previousRemovalNodeIndex != -1 && previousRemovalNodeIndex > previousNodeIndex)
 				{
 					ret.Add(node);
@@ -563,30 +479,13 @@ namespace OpenRA
 
 				// A previous node is present with no intervening Removal.
 				// We should merge the new one into it, in place.
-				ret[previousNodeIndex] = node.WithValue(MergePartial(ret[previousNodeIndex].Value, node.Value));
+				ret[previousNodeIndex] = new MiniYamlNode(node.Key, MergePartial(ret[previousNodeIndex].Value, node.Value), node.Comment, node.Location);
 			}
 
+			ret.TrimExcess();
 			return ret;
 		}
 
-		static int IndexOfKey(List<MiniYamlNode> nodes, string key)
-		{
-			// PERF: Avoid LINQ.
-			for (var i = 0; i < nodes.Count; i++)
-				if (nodes[i].Key == key)
-					return i;
-			return -1;
-		}
-
-		static int LastIndexOfKey(List<MiniYamlNode> nodes, string key)
-		{
-			// PERF: Avoid LINQ.
-			for (var i = nodes.Count - 1; i >= 0; i--)
-				if (nodes[i].Key == key)
-					return i;
-			return -1;
-		}
-
 		public IEnumerable<string> ToLines(string key, string comment = null)
 		{
 			var hasKey = !string.IsNullOrEmpty(key);
@@ -609,100 +508,14 @@ namespace OpenRA
 				files = files.Append(mapFiles);
 			}
 
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
-			IEnumerable<IReadOnlyCollection<MiniYamlNode>> yaml = files.Select(s => FromStream(fileSystem.Open(s), s, stringPool: stringPool));
-			if (mapRules != null && mapRules.Nodes.Length > 0)
+			var yaml = files.Select(s => FromStream(fileSystem.Open(s), s));
+			if (mapRules != null && mapRules.Nodes.Count > 0)
 				yaml = yaml.Append(mapRules.Nodes);
 
 			return Merge(yaml);
 		}
 	}
 
-	public sealed class MiniYamlNodeBuilder
-	{
-		public MiniYamlNode.SourceLocation Location;
-		public string Key;
-		public MiniYamlBuilder Value;
-		public string Comment;
-
-		public MiniYamlNodeBuilder(MiniYamlNode node)
-		{
-			Location = node.Location;
-			Key = node.Key;
-			Value = new MiniYamlBuilder(node.Value);
-			Comment = node.Comment;
-		}
-
-		public MiniYamlNodeBuilder(string k, MiniYamlBuilder v, string c = null)
-		{
-			Key = k;
-			Value = v;
-			Comment = c;
-		}
-
-		public MiniYamlNodeBuilder(string k, MiniYamlBuilder v, string c, MiniYamlNode.SourceLocation loc)
-			: this(k, v, c)
-		{
-			Location = loc;
-		}
-
-		public MiniYamlNodeBuilder(string k, string v, string c = null)
-			: this(k, new MiniYamlBuilder(v, null), c) { }
-
-		public MiniYamlNodeBuilder(string k, string v, List<MiniYamlNode> n)
-			: this(k, new MiniYamlBuilder(v, n), null) { }
-
-		public MiniYamlNode Build()
-		{
-			return new MiniYamlNode(Key, Value.Build(), Comment, Location);
-		}
-	}
-
-	public sealed class MiniYamlBuilder
-	{
-		public string Value;
-		public List<MiniYamlNodeBuilder> Nodes;
-
-		public MiniYamlBuilder(MiniYaml yaml)
-		{
-			Value = yaml.Value;
-			Nodes = yaml.Nodes.Select(n => new MiniYamlNodeBuilder(n)).ToList();
-		}
-
-		public MiniYamlBuilder(string value)
-			: this(value, null) { }
-
-		public MiniYamlBuilder(string value, List<MiniYamlNode> nodes)
-		{
-			Value = value;
-			Nodes = nodes == null ? new List<MiniYamlNodeBuilder>() : nodes.ConvertAll(x => new MiniYamlNodeBuilder(x));
-		}
-
-		public MiniYaml Build()
-		{
-			return new MiniYaml(Value, Nodes.Select(n => n.Build()));
-		}
-
-		public IEnumerable<string> ToLines(string key, string comment = null)
-		{
-			var hasKey = !string.IsNullOrEmpty(key);
-			var hasValue = !string.IsNullOrEmpty(Value);
-			var hasComment = comment != null;
-			yield return (hasKey ? key + ":" : "")
-				+ (hasValue ? " " + Value.Replace("#", "\\#") : "")
-				+ (hasComment ? (hasKey || hasValue ? " " : "") + "#" + comment : "");
-
-			if (Nodes != null)
-				foreach (var line in Nodes.ToLines())
-					yield return "\t" + line;
-		}
-
-		public MiniYamlNodeBuilder NodeWithKeyOrDefault(string key)
-		{
-			return Nodes.SingleOrDefault(n => n.Key == key);
-		}
-	}
-
 	[Serializable]
 	public class YamlException : Exception
 	{

OpenRA.Game/ModData.cs

@@ -33,6 +33,7 @@ namespace OpenRA
 		public readonly ISpriteLoader[] SpriteLoaders;
 		public readonly ITerrainLoader TerrainLoader;
 		public readonly ISpriteSequenceLoader SpriteSequenceLoader;
+		public readonly IModelSequenceLoader ModelSequenceLoader;
 		public readonly IVideoLoader[] VideoLoaders;
 		public readonly HotkeyManager Hotkeys;
 		public ILoadScreen LoadScreen { get; }
@@ -89,6 +90,15 @@ namespace OpenRA
 
 			SpriteSequenceLoader = (ISpriteSequenceLoader)sequenceCtor.Invoke(new[] { this });
 
+			var modelFormat = Manifest.Get<ModelSequenceFormat>();
+			var modelLoader = ObjectCreator.FindType(modelFormat.Type + "Loader");
+			var modelCtor = modelLoader?.GetConstructor(new[] { typeof(ModData) });
+			if (modelLoader == null || !modelLoader.GetInterfaces().Contains(typeof(IModelSequenceLoader)) || modelCtor == null)
+				throw new InvalidOperationException($"Unable to find a model loader for type '{modelFormat.Type}'.");
+
+			ModelSequenceLoader = (IModelSequenceLoader)modelCtor.Invoke(new[] { this });
+			ModelSequenceLoader.OnMissingModelError = s => Log.Write("debug", s);
+
 			Hotkeys = new HotkeyManager(ModFiles, Game.Settings.Keys, Manifest);
 
 			defaultRules = Exts.Lazy(() => Ruleset.LoadDefaults(this));
@@ -158,8 +168,7 @@ namespace OpenRA
 
 		public List<MiniYamlNode>[] GetRulesYaml()
 		{
-			var stringPool = new HashSet<string>(); // Reuse common strings in YAML
-			return Manifest.Rules.Select(s => MiniYaml.FromStream(DefaultFileSystem.Open(s), s, stringPool: stringPool)).ToArray();
+			return Manifest.Rules.Select(s => MiniYaml.FromStream(DefaultFileSystem.Open(s), s)).ToArray();
 		}
 
 		public void Dispose()

OpenRA.Game/Network/Connection.cs

@@ -260,15 +260,15 @@ namespace OpenRA.Network
 			try
 			{
 				var ms = new MemoryStream();
-				ms.Write(packet.Length);
-				ms.Write(packet);
+				ms.WriteArray(BitConverter.GetBytes(packet.Length));
+				ms.WriteArray(packet);
 
 				foreach (var s in queuedSyncPackets)
 				{
 					var q = OrderIO.SerializeSync(s);
 
-					ms.Write(q.Length);
-					ms.Write(q);
+					ms.WriteArray(BitConverter.GetBytes(q.Length));
+					ms.WriteArray(q);
 
 					sentSync.Enqueue(s);
 				}

OpenRA.Game/Network/GameSave.cs

@@ -122,10 +122,10 @@ namespace OpenRA.Network
 				LastSyncFrame = rs.ReadInt32();
 				lastSyncPacket = rs.ReadBytes(Order.SyncHashOrderLength);
 
-				var globalSettings = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:globalSettings");
+				var globalSettings = MiniYaml.FromString(rs.ReadString(Encoding.UTF8, Connection.MaxOrderLength));
 				GlobalSettings = Session.Global.Deserialize(globalSettings[0].Value);
 
-				var slots = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slots");
+				var slots = MiniYaml.FromString(rs.ReadString(Encoding.UTF8, Connection.MaxOrderLength));
 				Slots = new Dictionary<string, Session.Slot>();
 				foreach (var s in slots)
 				{
@@ -133,7 +133,7 @@ namespace OpenRA.Network
 					Slots.Add(slot.PlayerReference, slot);
 				}
 
-				var slotClients = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:slotClients");
+				var slotClients = MiniYaml.FromString(rs.ReadString(Encoding.UTF8, Connection.MaxOrderLength));
 				SlotClients = new Dictionary<string, SlotClient>();
 				foreach (var s in slotClients)
 				{
@@ -144,9 +144,9 @@ namespace OpenRA.Network
 				if (rs.Position != traitDataOffset || rs.ReadInt32() != TraitDataMarker)
 					throw new InvalidDataException("Invalid orasav file");
 
-				var traitData = MiniYaml.FromString(rs.ReadLengthPrefixedString(Encoding.UTF8, Connection.MaxOrderLength), $"{filepath}:traitData");
+				var traitData = MiniYaml.FromString(rs.ReadString(Encoding.UTF8, Connection.MaxOrderLength));
 				foreach (var td in traitData)
-					TraitData.Add(Exts.ParseInt32Invariant(td.Key), td.Value);
+					TraitData.Add(int.Parse(td.Key), td.Value);
 
 				rs.Seek(0, SeekOrigin.Begin);
 				ordersStream.Write(rs.ReadBytes(metadataOffset), 0, metadataOffset);
@@ -226,10 +226,10 @@ namespace OpenRA.Network
 				clientSlot = firstBotSlotIndex;
 			}
 
-			ordersStream.Write(data.Length + 8);
-			ordersStream.Write(frame);
-			ordersStream.Write(clientSlot);
-			ordersStream.Write(data);
+			ordersStream.WriteArray(BitConverter.GetBytes(data.Length + 8));
+			ordersStream.WriteArray(BitConverter.GetBytes(frame));
+			ordersStream.WriteArray(BitConverter.GetBytes(clientSlot));
+			ordersStream.WriteArray(data);
 			LastOrdersFrame = frame;
 		}
 
@@ -238,7 +238,7 @@ namespace OpenRA.Network
 			// Send the trait data first to guarantee that it is available when needed
 			foreach (var kv in TraitData)
 			{
-				var data = new List<MiniYamlNode>() { new(kv.Key.ToStringInvariant(), kv.Value) }.WriteToString();
+				var data = new List<MiniYamlNode>() { new MiniYamlNode(kv.Key.ToString(), kv.Value) }.WriteToString();
 				packetFn(0, 0, Order.FromTargetString("SaveTraitData", data, true).Serialize());
 			}
 
@@ -288,35 +288,35 @@ namespace OpenRA.Network
 			{
 				ordersStream.Seek(0, SeekOrigin.Begin);
 				ordersStream.CopyTo(file);
-				file.Write(MetadataMarker);
-				file.Write(LastOrdersFrame);
-				file.Write(LastSyncFrame);
+				file.Write(BitConverter.GetBytes(MetadataMarker), 0, 4);
+				file.Write(BitConverter.GetBytes(LastOrdersFrame), 0, 4);
+				file.Write(BitConverter.GetBytes(LastSyncFrame), 0, 4);
 				file.Write(lastSyncPacket, 0, Order.SyncHashOrderLength);
 
 				var globalSettingsNodes = new List<MiniYamlNode>() { GlobalSettings.Serialize() };
-				file.WriteLengthPrefixedString(Encoding.UTF8, globalSettingsNodes.WriteToString());
+				file.WriteString(Encoding.UTF8, globalSettingsNodes.WriteToString());
 
 				var slotNodes = Slots
 					.Select(s => s.Value.Serialize())
 					.ToList();
-				file.WriteLengthPrefixedString(Encoding.UTF8, slotNodes.WriteToString());
+				file.WriteString(Encoding.UTF8, slotNodes.WriteToString());
 
 				var slotClientNodes = SlotClients
 					.Select(s => s.Value.Serialize(s.Key))
 					.ToList();
-				file.WriteLengthPrefixedString(Encoding.UTF8, slotClientNodes.WriteToString());
+				file.WriteString(Encoding.UTF8, slotClientNodes.WriteToString());
 
 				var traitDataOffset = file.Length;
-				file.Write(TraitDataMarker);
+				file.Write(BitConverter.GetBytes(TraitDataMarker), 0, 4);
 
 				var traitDataNodes = TraitData
-					.Select(kv => new MiniYamlNode(kv.Key.ToStringInvariant(), kv.Value))
+					.Select(kv => new MiniYamlNode(kv.Key.ToString(), kv.Value))
 					.ToList();
-				file.WriteLengthPrefixedString(Encoding.UTF8, traitDataNodes.WriteToString());
+				file.WriteString(Encoding.UTF8, traitDataNodes.WriteToString());
 
-				file.Write((int)ordersStream.Length);
-				file.Write((int)traitDataOffset);
-				file.Write(EOFMarker);
+				file.Write(BitConverter.GetBytes(ordersStream.Length), 0, 4);
+				file.Write(BitConverter.GetBytes(traitDataOffset), 0, 4);
+				file.Write(BitConverter.GetBytes(EOFMarker), 0, 4);
 			}
 		}
 	}

OpenRA.Game/Network/GameServer.cs

@@ -140,7 +140,7 @@ namespace OpenRA.Network
 		static object LoadClients(MiniYaml yaml)
 		{
 			var clients = new List<GameClient>();
-			var clientsNode = yaml.NodeWithKeyOrDefault("Clients");
+			var clientsNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Clients");
 			if (clientsNode != null)
 			{
 				var regex = new Regex(@"Client@\d+");
@@ -159,7 +159,7 @@ namespace OpenRA.Network
 			// Games advertised using the old API used a single Mods field
 			if (Mod == null || Version == null)
 			{
-				var modsNode = yaml.NodeWithKeyOrDefault("Mods");
+				var modsNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Mods");
 				if (modsNode != null)
 				{
 					var modVersion = modsNode.Value.Value.Split('@');
@@ -169,8 +169,9 @@ namespace OpenRA.Network
 			}
 
 			// Games advertised using the old API calculated the play time locally
-			if (State == 2 && PlayTime < 0 && DateTime.TryParse(Started, out var startTime))
-				PlayTime = (int)(DateTime.UtcNow - startTime).TotalSeconds;
+			if (State == 2 && PlayTime < 0)
+				if (DateTime.TryParse(Started, out var startTime))
+					PlayTime = (int)(DateTime.UtcNow - startTime).TotalSeconds;
 
 			var externalKey = ExternalMod.MakeKey(Mod, Version);
 			if (Game.ExternalMods.TryGetValue(externalKey, out var external) && external.Version == Version)
@@ -216,7 +217,7 @@ namespace OpenRA.Network
 			Name = server.Settings.Name;
 
 			// IP address will be replaced with a real value by the master server / receiving LAN client
-			Address = "0.0.0.0:" + server.Settings.ListenPort.ToStringInvariant();
+			Address = "0.0.0.0:" + server.Settings.ListenPort.ToString();
 			State = (int)server.State;
 			MaxPlayers = server.LobbyInfo.Slots.Count(s => !s.Value.Closed) - server.LobbyInfo.Clients.Count(c1 => c1.Bot != null);
 			Map = server.Map.Uid;
@@ -233,7 +234,7 @@ namespace OpenRA.Network
 
 		public string ToPOSTData(bool lanGame)
 		{
-			var root = new List<MiniYamlNode>() { new("Protocol", ProtocolVersion.ToStringInvariant()) };
+			var root = new List<MiniYamlNode>() { new MiniYamlNode("Protocol", ProtocolVersion.ToString()) };
 			foreach (var field in SerializeFields)
 				root.Add(FieldSaver.SaveField(this, field));
 
@@ -242,16 +243,18 @@ namespace OpenRA.Network
 				// Add fields that are normally generated by the master server
 				// LAN games overload the Id with a GUID string (rather than an ID) to allow deduplication
 				root.Add(new MiniYamlNode("Id", Platform.SessionGUID.ToString()));
-				root.Add(new MiniYamlNode("Players", Clients.Count(c => !c.IsBot && !c.IsSpectator).ToStringInvariant()));
-				root.Add(new MiniYamlNode("Spectators", Clients.Count(c => c.IsSpectator).ToStringInvariant()));
-				root.Add(new MiniYamlNode("Bots", Clients.Count(c => c.IsBot).ToStringInvariant()));
+				root.Add(new MiniYamlNode("Players", Clients.Count(c => !c.IsBot && !c.IsSpectator).ToString()));
+				root.Add(new MiniYamlNode("Spectators", Clients.Count(c => c.IsSpectator).ToString()));
+				root.Add(new MiniYamlNode("Bots", Clients.Count(c => c.IsBot).ToString()));
 
 				// Included for backwards compatibility with older clients that don't support separated Mod/Version.
 				root.Add(new MiniYamlNode("Mods", Mod + "@" + Version));
 			}
 
-			var clientsNode = new MiniYaml("", Clients.Select((c, i) =>
-				new MiniYamlNode("Client@" + i, FieldSaver.Save(c))));
+			var clientsNode = new MiniYaml("");
+			var i = 0;
+			foreach (var c in Clients)
+				clientsNode.Nodes.Add(new MiniYamlNode("Client@" + i++.ToString(), FieldSaver.Save(c)));
 
 			root.Add(new MiniYamlNode("Clients", clientsNode));
 			return new MiniYaml("", root)

OpenRA.Game/Network/Handshake.cs

@@ -20,16 +20,16 @@ namespace OpenRA.Network
 		public string Version;
 		public string AuthToken;
 
-		public static HandshakeRequest Deserialize(string data, string name)
+		public static HandshakeRequest Deserialize(string data)
 		{
 			var handshake = new HandshakeRequest();
-			FieldLoader.Load(handshake, MiniYaml.FromString(data, name).First().Value);
+			FieldLoader.Load(handshake, MiniYaml.FromString(data).First().Value);
 			return handshake;
 		}
 
 		public string Serialize()
 		{
-			var data = new List<MiniYamlNode> { new("Handshake", FieldSaver.Save(this)) };
+			var data = new List<MiniYamlNode> { new MiniYamlNode("Handshake", FieldSaver.Save(this)) };
 			return data.WriteToString();
 		}
 	}
@@ -51,14 +51,14 @@ namespace OpenRA.Network
 		[FieldLoader.Ignore]
 		public Session.Client Client;
 
-		public static HandshakeResponse Deserialize(string data, string name)
+		public static HandshakeResponse Deserialize(string data)
 		{
 			var handshake = new HandshakeResponse
 			{
 				Client = new Session.Client()
 			};
 
-			var ys = MiniYaml.FromString(data, name);
+			var ys = MiniYaml.FromString(data);
 			foreach (var y in ys)
 			{
 				switch (y.Key)
@@ -79,9 +79,9 @@ namespace OpenRA.Network
 		{
 			var data = new List<MiniYamlNode>
 			{
-				new("Handshake", null,
+				new MiniYamlNode("Handshake", null,
 					new[] { "Mod", "Version", "Password", "Fingerprint", "AuthSignature", "OrdersProtocol" }.Select(p => FieldSaver.SaveField(this, p)).ToList()),
-				new("Client", FieldSaver.Save(Client))
+				new MiniYamlNode("Client", FieldSaver.Save(Client))
 			};
 
 			return data.WriteToString();

OpenRA.Game/Network/LocalizedMessage.cs

@@ -9,8 +9,10 @@
  */
 #endregion
 
+using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text.RegularExpressions;
 using Linguini.Shared.Types.Bundle;
 
 namespace OpenRA.Network
@@ -55,51 +57,61 @@ namespace OpenRA.Network
 		public readonly string Key = string.Empty;
 
 		[FieldLoader.LoadUsing(nameof(LoadArguments))]
-		public readonly Dictionary<string, object> Arguments;
+		public readonly FluentArgument[] Arguments = Array.Empty<FluentArgument>();
+
+		public string TranslatedText { get; }
 
 		static object LoadArguments(MiniYaml yaml)
 		{
-			var arguments = new Dictionary<string, object>();
-			var argumentsNode = yaml.NodeWithKeyOrDefault("Arguments");
+			var arguments = new List<FluentArgument>();
+			var argumentsNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Arguments");
 			if (argumentsNode != null)
 			{
-				foreach (var argumentNode in argumentsNode.Value.Nodes)
-				{
-					var argument = FieldLoader.Load<FluentArgument>(argumentNode.Value);
-					if (argument.Type == FluentArgument.FluentArgumentType.Number)
-					{
-						if (!double.TryParse(argument.Value, out var number))
-							Log.Write("debug", $"Failed to parse {argument.Value}");
-
-						arguments.Add(argument.Key, number);
-					}
-					else
-						arguments.Add(argument.Key, argument.Value);
-				}
+				var regex = new Regex(@"Argument@\d+");
+				foreach (var argument in argumentsNode.Value.Nodes)
+					if (regex.IsMatch(argument.Key))
+						arguments.Add(FieldLoader.Load<FluentArgument>(argument.Value));
 			}
 
-			return arguments;
+			return arguments.ToArray();
 		}
 
 		public LocalizedMessage(MiniYaml yaml)
 		{
 			// Let the FieldLoader do the dirty work of loading the public fields.
 			FieldLoader.Load(this, yaml);
+
+			var argumentDictionary = new Dictionary<string, object>();
+			foreach (var argument in Arguments)
+			{
+				if (argument.Type == FluentArgument.FluentArgumentType.Number)
+				{
+					if (!double.TryParse(argument.Value, out var number))
+						Log.Write("debug", $"Failed to parse {argument.Value}");
+
+					argumentDictionary.Add(argument.Key, number);
+				}
+				else
+					argumentDictionary.Add(argument.Key, argument.Value);
+			}
+
+			TranslatedText = TranslationProvider.GetString(Key, argumentDictionary);
 		}
 
 		public static string Serialize(string key, Dictionary<string, object> arguments = null)
 		{
 			var root = new List<MiniYamlNode>
 			{
-				new("Protocol", ProtocolVersion.ToStringInvariant()),
-				new("Key", key)
+				new MiniYamlNode("Protocol", ProtocolVersion.ToString()),
+				new MiniYamlNode("Key", key)
 			};
 
 			if (arguments != null)
 			{
-				var argumentsNode = new MiniYaml("", arguments
-					.Select(a => new FluentArgument(a.Key, a.Value))
-					.Select((argument, i) => new MiniYamlNode("Argument@" + i, FieldSaver.Save(argument))));
+				var argumentsNode = new MiniYaml("");
+				var i = 0;
+				foreach (var argument in arguments.Select(a => new FluentArgument(a.Key, a.Value)))
+					argumentsNode.Nodes.Add(new MiniYamlNode("Argument@" + i++, FieldSaver.Save(argument)));
 
 				root.Add(new MiniYamlNode("Arguments", argumentsNode));
 			}

OpenRA.Game/Network/Order.cs

@@ -156,18 +156,7 @@ namespace OpenRA
 									else
 									{
 										var pos = new WPos(r.ReadInt32(), r.ReadInt32(), r.ReadInt32());
-
-										var numberOfTerrainPositions = r.ReadInt16();
-										if (numberOfTerrainPositions == -1)
-											target = Target.FromPos(pos);
-										else
-										{
-											var terrainPositions = new WPos[numberOfTerrainPositions];
-											for (var i = 0; i < numberOfTerrainPositions; i++)
-												terrainPositions[i] = new WPos(r.ReadInt32(), r.ReadInt32(), r.ReadInt32());
-
-											target = Target.FromSerializedTerrainPosition(pos, terrainPositions);
-										}
+										target = Target.FromPos(pos);
 									}
 
 									break;
@@ -399,21 +388,6 @@ namespace OpenRA
 									w.Write(targetState.Pos.X);
 									w.Write(targetState.Pos.Y);
 									w.Write(targetState.Pos.Z);
-
-									// Don't send extra data over the network that will be restored by the Target ctor
-									var terrainPositions = targetState.TerrainPositions.Length;
-									if (terrainPositions == 1 && targetState.TerrainPositions[0] == targetState.Pos)
-										w.Write((short)-1);
-									else
-									{
-										w.Write((short)terrainPositions);
-										foreach (var position in targetState.TerrainPositions)
-										{
-											w.Write(position.X);
-											w.Write(position.Y);
-											w.Write(position.Z);
-										}
-									}
 								}
 
 								break;

OpenRA.Game/Network/OrderIO.cs

@@ -27,7 +27,7 @@ namespace OpenRA.Network
 			// the Order objects directly on the local client.
 			data = new MemoryStream();
 			foreach (var o in orders)
-				data.Write(o.Serialize());
+				data.WriteArray(o.Serialize());
 		}
 
 		public OrderPacket(MemoryStream data)
@@ -55,7 +55,7 @@ namespace OpenRA.Network
 		public byte[] Serialize(int frame)
 		{
 			var ms = new MemoryStream((int)data.Length + 4);
-			ms.Write(frame);
+			ms.WriteArray(BitConverter.GetBytes(frame));
 
 			data.Position = 0;
 			data.CopyTo(ms);
@@ -83,19 +83,19 @@ namespace OpenRA.Network
 		public static byte[] SerializeSync((int Frame, int SyncHash, ulong DefeatState) data)
 		{
 			var ms = new MemoryStream(4 + Order.SyncHashOrderLength);
-			ms.Write(data.Frame);
+			ms.WriteArray(BitConverter.GetBytes(data.Frame));
 			ms.WriteByte((byte)OrderType.SyncHash);
-			ms.Write(data.SyncHash);
-			ms.Write(data.DefeatState);
+			ms.WriteArray(BitConverter.GetBytes(data.SyncHash));
+			ms.WriteArray(BitConverter.GetBytes(data.DefeatState));
 			return ms.GetBuffer();
 		}
 
 		public static byte[] SerializePingResponse(long timestamp, byte queueLength)
 		{
 			var ms = new MemoryStream(14);
-			ms.Write(0);
+			ms.WriteArray(BitConverter.GetBytes(0));
 			ms.WriteByte((byte)OrderType.Ping);
-			ms.Write(timestamp);
+			ms.WriteArray(BitConverter.GetBytes(timestamp));
 			ms.WriteByte(queueLength);
 			return ms.GetBuffer();
 		}

OpenRA.Game/Network/OrderManager.cs

@@ -22,9 +22,6 @@ namespace OpenRA.Network
 	{
 		const OrderPacket ClientDisconnected = null;
 
-		[TranslationReference("frame")]
-		const string DesyncCompareLogs = "notification-desync-compare-logs";
-
 		readonly SyncReport syncReport;
 		readonly Dictionary<int, Queue<(int Frame, OrderPacket Orders)>> pendingOrders = new();
 		readonly Dictionary<int, (int SyncHash, ulong DefeatState)> syncForFrame = new();
@@ -39,9 +36,6 @@ namespace OpenRA.Network
 		public string ServerError = null;
 		public bool AuthenticationFailed = false;
 
-		// The default null means "no map restriction" while an empty set means "all maps restricted"
-		public HashSet<string> ServerMapPool = null;
-
 		public int NetFrameNumber { get; private set; }
 		public int LocalFrameNumber;
 
@@ -76,7 +70,7 @@ namespace OpenRA.Network
 			public int Client;
 			public Order Order;
 
-			public override readonly string ToString()
+			public override string ToString()
 			{
 				return $"ClientId: {Client} {Order}";
 			}
@@ -91,7 +85,7 @@ namespace OpenRA.Network
 			World.OutOfSync();
 			IsOutOfSync = true;
 
-			TextNotificationsManager.AddSystemLine(DesyncCompareLogs, Translation.Arguments("frame", frame));
+			TextNotificationsManager.AddSystemLine($"Out of sync in frame {frame}.\nCompare syncreport.log with other players.");
 		}
 
 		public void StartGame()

OpenRA.Game/Network/ReplayConnection.cs

@@ -69,7 +69,7 @@ namespace OpenRA.Network
 								if (o.OrderString == "StartGame")
 									IsValid = true;
 								else if (o.OrderString == "SyncInfo" && !IsValid)
-									LobbyInfo = Session.Deserialize(o.TargetString, o.OrderString);
+									LobbyInfo = Session.Deserialize(o.TargetString);
 							}
 						}
 					}

OpenRA.Game/Network/ReplayRecorder.cs

@@ -67,7 +67,7 @@ namespace OpenRA.Network
 				}
 			}
 
-			file.Write(initialContent);
+			file.WriteArray(initialContent);
 			writer = new BinaryWriter(file);
 		}
 
@@ -92,8 +92,8 @@ namespace OpenRA.Network
 		public void ReceiveFrame(int clientID, int frame, byte[] data)
 		{
 			var ms = new MemoryStream(4 + data.Length);
-			ms.Write(frame);
-			ms.Write(data);
+			ms.WriteArray(BitConverter.GetBytes(frame));
+			ms.WriteArray(data);
 			Receive(clientID, ms.GetBuffer());
 		}
 

OpenRA.Game/Network/Session.cs

@@ -41,13 +41,13 @@ namespace OpenRA.Network
 			return null;
 		}
 
-		public static Session Deserialize(string data, string name)
+		public static Session Deserialize(string data)
 		{
 			try
 			{
 				var session = new Session();
 
-				var nodes = MiniYaml.FromString(data, name);
+				var nodes = MiniYaml.FromString(data);
 				foreach (var node in nodes)
 				{
 					var strings = node.Key.Split('@');
@@ -227,7 +227,7 @@ namespace OpenRA.Network
 			{
 				var gs = FieldLoader.Load<Global>(data);
 
-				var optionsNode = data.NodeWithKeyOrDefault("Options");
+				var optionsNode = data.Nodes.FirstOrDefault(n => n.Key == "Options");
 				if (optionsNode != null)
 					foreach (var n in optionsNode.Value.Nodes)
 						gs.LobbyOptions[n.Key] = FieldLoader.Load<LobbyOptionState>(n.Value);
@@ -238,9 +238,8 @@ namespace OpenRA.Network
 			public MiniYamlNode Serialize()
 			{
 				var data = new MiniYamlNode("GlobalSettings", FieldSaver.Save(this));
-				var options = LobbyOptions.Select(kv => new MiniYamlNode(kv.Key, FieldSaver.Save(kv.Value)));
-				data = data.WithValue(data.Value.WithNodesAppended(
-					new[] { new MiniYamlNode("Options", new MiniYaml(null, options)) }));
+				var options = LobbyOptions.Select(kv => new MiniYamlNode(kv.Key, FieldSaver.Save(kv.Value))).ToList();
+				data.Value.Nodes.Add(new MiniYamlNode("Options", new MiniYaml(null, options)));
 				return data;
 			}
 
@@ -265,7 +264,7 @@ namespace OpenRA.Network
 		{
 			var sessionData = new List<MiniYamlNode>()
 			{
-				new("DisabledSpawnPoints", FieldSaver.FormatValue(DisabledSpawnPoints))
+				new MiniYamlNode("DisabledSpawnPoints", FieldSaver.FormatValue(DisabledSpawnPoints))
 			};
 
 			foreach (var client in Clients)

OpenRA.Game/Network/SyncReport.cs

@@ -201,12 +201,8 @@ namespace OpenRA.Network
 			public TypeInfo(Type type)
 			{
 				const BindingFlags Flags = BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance;
-				var fields = type.GetFields(Flags)
-					.Where(fi => !fi.IsLiteral && !fi.IsStatic && fi.HasAttribute<SyncAttribute>())
-					.ToList();
-				var properties = type.GetProperties(Flags)
-					.Where(pi => pi.HasAttribute<SyncAttribute>())
-					.ToList();
+				var fields = type.GetFields(Flags).Where(fi => !fi.IsLiteral && !fi.IsStatic && fi.HasAttribute<SyncAttribute>());
+				var properties = type.GetProperties(Flags).Where(pi => pi.HasAttribute<SyncAttribute>());
 
 				foreach (var prop in properties)
 					if (!prop.CanRead || prop.GetIndexParameters().Length > 0)
@@ -304,7 +300,7 @@ namespace OpenRA.Network
 
 			public object this[int index]
 			{
-				readonly get
+				get
 				{
 					if (item2OrSentinel == Sentinel)
 						return ((object[])item1OrArray)[index];

OpenRA.Game/Network/UnitOrders.cs

@@ -20,24 +20,6 @@ namespace OpenRA.Network
 	{
 		public const int ChatMessageMaxLength = 2500;
 
-		[TranslationReference("player")]
-		const string Joined = "notification-joined";
-
-		[TranslationReference("player")]
-		const string Left = "notification-lobby-disconnected";
-
-		[TranslationReference]
-		const string GameStarted = "notification-game-has-started";
-
-		[TranslationReference]
-		const string GameSaved = "notification-game-saved";
-
-		[TranslationReference("player")]
-		const string GamePaused = "notification-game-paused";
-
-		[TranslationReference("player")]
-		const string GameUnpaused = "notification-game-unpaused";
-
 		public static int? KickVoteTarget { get; internal set; }
 
 		static Player FindPlayerByClient(this World world, Session.Client c)
@@ -58,350 +40,342 @@ namespace OpenRA.Network
 
 				// Client side translated server message
 				case "LocalizedMessage":
-				{
-					if (string.IsNullOrEmpty(order.TargetString))
-						break;
-
-					var yaml = MiniYaml.FromString(order.TargetString, order.OrderString);
-					foreach (var node in yaml)
 					{
-						var localizedMessage = new LocalizedMessage(node.Value);
-						if (localizedMessage.Key == Joined)
-							TextNotificationsManager.AddPlayerJoinedLine(localizedMessage.Key, localizedMessage.Arguments);
-						else if (localizedMessage.Key == Left)
-							TextNotificationsManager.AddPlayerLeftLine(localizedMessage.Key, localizedMessage.Arguments);
-						else
-							TextNotificationsManager.AddSystemLine(localizedMessage.Key, localizedMessage.Arguments);
-					}
+						if (string.IsNullOrEmpty(order.TargetString))
+							break;
 
-					break;
-				}
+						var yaml = MiniYaml.FromString(order.TargetString);
+						foreach (var node in yaml)
+						{
+							var localizedMessage = new LocalizedMessage(node.Value);
+							TextNotificationsManager.AddSystemLine(localizedMessage.TranslatedText);
+						}
+
+						break;
+					}
 
 				case "DisableChatEntry":
-				{
-					if (OrderNotFromServerOrWorldIsReplay(clientId, world))
+					{
+						if (OrderNotFromServerOrWorldIsReplay(clientId, world))
+							break;
+
+						// Server may send MaxValue to indicate that it is disabled until further notice
+						if (order.ExtraData == uint.MaxValue)
+							TextNotificationsManager.ChatDisabledUntil = uint.MaxValue;
+						else
+							TextNotificationsManager.ChatDisabledUntil = Game.RunTime + order.ExtraData;
+
 						break;
-
-					// Server may send MaxValue to indicate that it is disabled until further notice
-					if (order.ExtraData == uint.MaxValue)
-						TextNotificationsManager.ChatDisabledUntil = uint.MaxValue;
-					else
-						TextNotificationsManager.ChatDisabledUntil = Game.RunTime + order.ExtraData;
-
-					break;
-				}
+					}
 
 				case "StartKickVote":
-				{
-					if (OrderNotFromServerOrWorldIsReplay(clientId, world))
-						break;
+					{
+						if (OrderNotFromServerOrWorldIsReplay(clientId, world))
+							break;
 
-					KickVoteTarget = (int)order.ExtraData;
-					break;
-				}
+						KickVoteTarget = (int)order.ExtraData;
+						break;
+					}
 
 				case "EndKickVote":
-				{
-					if (OrderNotFromServerOrWorldIsReplay(clientId, world))
+					{
+						if (OrderNotFromServerOrWorldIsReplay(clientId, world))
+							break;
+
+						if (KickVoteTarget == (int)order.ExtraData)
+							KickVoteTarget = null;
+
 						break;
-
-					if (KickVoteTarget == (int)order.ExtraData)
-						KickVoteTarget = null;
-
-					break;
-				}
+					}
 
 				case "Chat":
-				{
-					var client = orderManager.LobbyInfo.ClientWithIndex(clientId);
-					if (client == null)
-						break;
-
-					// Cut chat messages to the hard limit to avoid exploits
-					var message = order.TargetString;
-					if (message.Length > ChatMessageMaxLength)
-						message = order.TargetString[..ChatMessageMaxLength];
-
-					// ExtraData 0 means this is a normal chat order, everything else is team chat
-					if (order.ExtraData == 0)
 					{
-						var p = world?.FindPlayerByClient(client);
-						var suffix = (p != null && p.WinState == WinState.Lost) ? " (Dead)" : "";
-						suffix = client.IsObserver ? " (Spectator)" : suffix;
+						var client = orderManager.LobbyInfo.ClientWithIndex(clientId);
+						if (client == null)
+							break;
 
-						if (orderManager.LocalClient != null && client != orderManager.LocalClient && client.Team > 0 && client.Team == orderManager.LocalClient.Team)
-							suffix += " (Ally)";
+						// Cut chat messages to the hard limit to avoid exploits
+						var message = order.TargetString;
+						if (message.Length > ChatMessageMaxLength)
+							message = order.TargetString[..ChatMessageMaxLength];
 
-						TextNotificationsManager.AddChatLine(clientId, client.Name + suffix, message, client.Color);
-						break;
-					}
+						// ExtraData 0 means this is a normal chat order, everything else is team chat
+						if (order.ExtraData == 0)
+						{
+							var p = world?.FindPlayerByClient(client);
+							var suffix = (p != null && p.WinState == WinState.Lost) ? " (Dead)" : "";
+							suffix = client.IsObserver ? " (Spectator)" : suffix;
 
-					// We are still in the lobby
-					if (world == null)
-					{
-						var prefix = order.ExtraData == uint.MaxValue ? "[Spectators] " : "[Team] ";
-						if (orderManager.LocalClient != null && client.Team == orderManager.LocalClient.Team)
-							TextNotificationsManager.AddChatLine(clientId, prefix + client.Name, message, client.Color);
+							if (orderManager.LocalClient != null && client != orderManager.LocalClient && client.Team > 0 && client.Team == orderManager.LocalClient.Team)
+								suffix += " (Ally)";
+
+							TextNotificationsManager.AddChatLine(clientId, client.Name + suffix, message, client.Color);
+							break;
+						}
+
+						// We are still in the lobby
+						if (world == null)
+						{
+							var prefix = order.ExtraData == uint.MaxValue ? "[Spectators] " : "[Team] ";
+							if (orderManager.LocalClient != null && client.Team == orderManager.LocalClient.Team)
+								TextNotificationsManager.AddChatLine(clientId, prefix + client.Name, message, client.Color);
+
+							break;
+						}
+
+						var player = world.FindPlayerByClient(client);
+						var localClientIsObserver = world.IsReplay || (orderManager.LocalClient != null && orderManager.LocalClient.IsObserver)
+							|| (world.LocalPlayer != null && world.LocalPlayer.WinState != WinState.Undefined);
+
+						// ExtraData gives us the team number, uint.MaxValue means Spectators
+						if (order.ExtraData == uint.MaxValue && localClientIsObserver)
+						{
+							// Validate before adding the line
+							if (client.IsObserver || (player != null && player.WinState != WinState.Undefined))
+								TextNotificationsManager.AddChatLine(clientId, "[Spectators] " + client.Name, message, client.Color);
+
+							break;
+						}
+
+						var valid = client.Team == order.ExtraData && player != null && player.WinState == WinState.Undefined;
+						var isSameTeam = orderManager.LocalClient != null && order.ExtraData == orderManager.LocalClient.Team
+							&& world.LocalPlayer != null && world.LocalPlayer.WinState == WinState.Undefined;
+
+						if (valid && (isSameTeam || world.IsReplay))
+							TextNotificationsManager.AddChatLine(clientId, "[Team" + (world.IsReplay ? " " + order.ExtraData : "") + "] " + client.Name, message, client.Color);
 
 						break;
 					}
 
-					var player = world.FindPlayerByClient(client);
-					var localClientIsObserver = world.IsReplay || (orderManager.LocalClient != null && orderManager.LocalClient.IsObserver)
-						|| (world.LocalPlayer != null && world.LocalPlayer.WinState != WinState.Undefined);
-
-					// ExtraData gives us the team number, uint.MaxValue means Spectators
-					if (order.ExtraData == uint.MaxValue && localClientIsObserver)
-					{
-						// Validate before adding the line
-						if (client.IsObserver || (player != null && player.WinState != WinState.Undefined))
-							TextNotificationsManager.AddChatLine(clientId, "[Spectators] " + client.Name, message, client.Color);
-
-						break;
-					}
-
-					var valid = client.Team == order.ExtraData && player != null && player.WinState == WinState.Undefined;
-					var isSameTeam = orderManager.LocalClient != null && order.ExtraData == orderManager.LocalClient.Team
-						&& world.LocalPlayer != null && world.LocalPlayer.WinState == WinState.Undefined;
-
-					if (valid && (isSameTeam || world.IsReplay))
-						TextNotificationsManager.AddChatLine(clientId, "[Team" + (world.IsReplay ? " " + order.ExtraData : "") + "] " + client.Name, message, client.Color);
-
-					break;
-				}
-
 				case "StartGame":
-				{
-					if (Game.ModData.MapCache[orderManager.LobbyInfo.GlobalSettings.Map].Status != MapStatus.Available)
 					{
-						Game.Disconnect();
-						Game.LoadShellMap();
+						if (Game.ModData.MapCache[orderManager.LobbyInfo.GlobalSettings.Map].Status != MapStatus.Available)
+						{
+							Game.Disconnect();
+							Game.LoadShellMap();
 
-						// TODO: After adding a startup error dialog, notify the replay load failure.
+							// TODO: After adding a startup error dialog, notify the replay load failure.
+							break;
+						}
+
+						if (!string.IsNullOrEmpty(order.TargetString))
+						{
+							var data = MiniYaml.FromString(order.TargetString);
+							var saveLastOrdersFrame = data.FirstOrDefault(n => n.Key == "SaveLastOrdersFrame");
+							if (saveLastOrdersFrame != null)
+								orderManager.GameSaveLastFrame =
+									FieldLoader.GetValue<int>("saveLastOrdersFrame", saveLastOrdersFrame.Value.Value);
+
+							var saveSyncFrame = data.FirstOrDefault(n => n.Key == "SaveSyncFrame");
+							if (saveSyncFrame != null)
+								orderManager.GameSaveLastSyncFrame =
+									FieldLoader.GetValue<int>("SaveSyncFrame", saveSyncFrame.Value.Value);
+						}
+						else
+							TextNotificationsManager.AddSystemLine("The game has started.");
+
+						Game.StartGame(orderManager.LobbyInfo.GlobalSettings.Map, WorldType.Regular);
 						break;
 					}
 
-					if (!string.IsNullOrEmpty(order.TargetString))
-					{
-						var data = MiniYaml.FromString(order.TargetString, order.OrderString);
-						var saveLastOrdersFrame = data.FirstOrDefault(n => n.Key == "SaveLastOrdersFrame");
-						if (saveLastOrdersFrame != null)
-							orderManager.GameSaveLastFrame =
-								FieldLoader.GetValue<int>("saveLastOrdersFrame", saveLastOrdersFrame.Value.Value);
-
-						var saveSyncFrame = data.FirstOrDefault(n => n.Key == "SaveSyncFrame");
-						if (saveSyncFrame != null)
-							orderManager.GameSaveLastSyncFrame =
-								FieldLoader.GetValue<int>("SaveSyncFrame", saveSyncFrame.Value.Value);
-					}
-					else
-						TextNotificationsManager.AddSystemLine(GameStarted);
-
-					Game.StartGame(orderManager.LobbyInfo.GlobalSettings.Map, WorldType.Regular);
-					break;
-				}
-
 				case "SaveTraitData":
-				{
-					var data = MiniYaml.FromString(order.TargetString, order.OrderString)[0];
-					var traitIndex = Exts.ParseInt32Invariant(data.Key);
+					{
+						var data = MiniYaml.FromString(order.TargetString)[0];
+						var traitIndex = int.Parse(data.Key);
 
-					world?.AddGameSaveTraitData(traitIndex, data.Value);
+						world?.AddGameSaveTraitData(traitIndex, data.Value);
 
-					break;
-				}
+						break;
+					}
 
 				case "GameSaved":
 					if (!orderManager.World.IsReplay)
-						TextNotificationsManager.AddSystemLine(GameSaved);
+						TextNotificationsManager.AddSystemLine("Game saved");
 
 					foreach (var nsr in orderManager.World.WorldActor.TraitsImplementing<INotifyGameSaved>())
 						nsr.GameSaved(orderManager.World);
 					break;
 
 				case "PauseGame":
-				{
-					var client = orderManager.LobbyInfo.ClientWithIndex(clientId);
-					if (client != null)
 					{
-						var pause = order.TargetString == "Pause";
+						var client = orderManager.LobbyInfo.ClientWithIndex(clientId);
+						if (client != null)
+						{
+							var pause = order.TargetString == "Pause";
 
-						// Prevent injected unpause orders from restarting a finished game
-						if (orderManager.World.IsGameOver && !pause)
-							break;
+							// Prevent injected unpause orders from restarting a finished game
+							if (orderManager.World.IsGameOver && !pause)
+								break;
 
-						if (orderManager.World.Paused != pause && world != null && world.LobbyInfo.NonBotClients.Count() > 1)
-							TextNotificationsManager.AddSystemLine(pause ? GamePaused : GameUnpaused, Translation.Arguments("player", client.Name));
+							if (orderManager.World.Paused != pause && world != null && world.LobbyInfo.NonBotClients.Count() > 1)
+							{
+								var pausetext = $"The game is {(pause ? "paused" : "un-paused")} by {client.Name}";
+								TextNotificationsManager.AddSystemLine(pausetext);
+							}
 
-						orderManager.World.Paused = pause;
-						orderManager.World.PredictedPaused = pause;
+							orderManager.World.Paused = pause;
+							orderManager.World.PredictedPaused = pause;
+						}
+
+						break;
 					}
 
-					break;
-				}
-
 				case "HandshakeRequest":
-				{
-					// Switch to the server's mod if we need and are able to
-					var mod = Game.ModData.Manifest;
-					var request = HandshakeRequest.Deserialize(order.TargetString, order.OrderString);
-
-					var externalKey = ExternalMod.MakeKey(request.Mod, request.Version);
-					if ((request.Mod != mod.Id || request.Version != mod.Metadata.Version) &&
-						Game.ExternalMods.TryGetValue(externalKey, out var external))
 					{
-						// The ConnectionFailedLogic will prompt the user to switch mods
-						CurrentServerSettings.ServerExternalMod = external;
-						orderManager.Connection.Dispose();
+						// Switch to the server's mod if we need and are able to
+						var mod = Game.ModData.Manifest;
+						var request = HandshakeRequest.Deserialize(order.TargetString);
+
+						var externalKey = ExternalMod.MakeKey(request.Mod, request.Version);
+						if ((request.Mod != mod.Id || request.Version != mod.Metadata.Version) &&
+							Game.ExternalMods.TryGetValue(externalKey, out var external))
+						{
+							// The ConnectionFailedLogic will prompt the user to switch mods
+							CurrentServerSettings.ServerExternalMod = external;
+							orderManager.Connection.Dispose();
+							break;
+						}
+
+						Game.Settings.Player.Name = Settings.SanitizedPlayerName(Game.Settings.Player.Name);
+						Game.Settings.Save();
+
+						// Otherwise send the handshake with our current settings and let the server reject us
+						var info = new Session.Client()
+						{
+							Name = Game.Settings.Player.Name,
+							PreferredColor = Game.Settings.Player.Color,
+							Color = Game.Settings.Player.Color,
+							Faction = "Random",
+							SpawnPoint = 0,
+							Team = 0,
+							State = Session.ClientState.Invalid
+						};
+
+						var localProfile = Game.LocalPlayerProfile;
+						var response = new HandshakeResponse()
+						{
+							Client = info,
+							Mod = mod.Id,
+							Version = mod.Metadata.Version,
+							Password = CurrentServerSettings.Password,
+							Fingerprint = localProfile.Fingerprint,
+							OrdersProtocol = ProtocolVersion.Orders
+						};
+
+						if (request.AuthToken != null && response.Fingerprint != null)
+							response.AuthSignature = localProfile.Sign(request.AuthToken);
+
+						orderManager.IssueOrder(new Order("HandshakeResponse", null, false)
+						{
+							Type = OrderType.Handshake,
+							IsImmediate = true,
+							TargetString = response.Serialize()
+						});
+
 						break;
 					}
 
-					Game.Settings.Player.Name = Settings.SanitizedPlayerName(Game.Settings.Player.Name);
-					Game.Settings.Save();
-
-					// Otherwise send the handshake with our current settings and let the server reject us
-					var info = new Session.Client()
-					{
-						Name = Game.Settings.Player.Name,
-						PreferredColor = Game.Settings.Player.Color,
-						Color = Game.Settings.Player.Color,
-						Faction = "Random",
-						SpawnPoint = 0,
-						Team = 0,
-						State = Session.ClientState.Invalid
-					};
-
-					var localProfile = Game.LocalPlayerProfile;
-					var response = new HandshakeResponse()
-					{
-						Client = info,
-						Mod = mod.Id,
-						Version = mod.Metadata.Version,
-						Password = CurrentServerSettings.Password,
-						Fingerprint = localProfile.Fingerprint,
-						OrdersProtocol = ProtocolVersion.Orders
-					};
-
-					if (request.AuthToken != null && response.Fingerprint != null)
-						response.AuthSignature = localProfile.Sign(request.AuthToken);
-
-					orderManager.IssueOrder(new Order("HandshakeResponse", null, false)
-					{
-						Type = OrderType.Handshake,
-						IsImmediate = true,
-						TargetString = response.Serialize()
-					});
-
-					break;
-				}
-
 				case "ServerError":
-				{
-					orderManager.ServerError = order.TargetString;
-					orderManager.AuthenticationFailed = false;
-					break;
-				}
+					{
+						orderManager.ServerError = order.TargetString;
+						orderManager.AuthenticationFailed = false;
+						break;
+					}
 
 				case "AuthenticationError":
-				{
-					// The ConnectionFailedLogic will prompt the user for the password
-					orderManager.ServerError = order.TargetString;
-					orderManager.AuthenticationFailed = true;
-					break;
-				}
+					{
+						// The ConnectionFailedLogic will prompt the user for the password
+						orderManager.ServerError = order.TargetString;
+						orderManager.AuthenticationFailed = true;
+						break;
+					}
 
 				case "SyncInfo":
-				{
-					orderManager.LobbyInfo = Session.Deserialize(order.TargetString, order.OrderString);
-					Game.SyncLobbyInfo();
-					break;
-				}
+					{
+						orderManager.LobbyInfo = Session.Deserialize(order.TargetString);
+						Game.SyncLobbyInfo();
+						break;
+					}
 
 				case "SyncLobbyClients":
-				{
-					var clients = new List<Session.Client>();
-					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
-					foreach (var node in nodes)
 					{
-						var strings = node.Key.Split('@');
-						if (strings[0] == "Client")
-							clients.Add(Session.Client.Deserialize(node.Value));
-					}
+						var clients = new List<Session.Client>();
+						var nodes = MiniYaml.FromString(order.TargetString);
+						foreach (var node in nodes)
+						{
+							var strings = node.Key.Split('@');
+							if (strings[0] == "Client")
+								clients.Add(Session.Client.Deserialize(node.Value));
+						}
 
-					orderManager.LobbyInfo.Clients = clients;
-					Game.SyncLobbyInfo();
-					break;
-				}
+						orderManager.LobbyInfo.Clients = clients;
+						Game.SyncLobbyInfo();
+						break;
+					}
 
 				case "SyncLobbySlots":
-				{
-					var slots = new Dictionary<string, Session.Slot>();
-					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
-					foreach (var node in nodes)
 					{
-						var strings = node.Key.Split('@');
-						if (strings[0] == "Slot")
+						var slots = new Dictionary<string, Session.Slot>();
+						var nodes = MiniYaml.FromString(order.TargetString);
+						foreach (var node in nodes)
 						{
-							var slot = Session.Slot.Deserialize(node.Value);
-							slots.Add(slot.PlayerReference, slot);
+							var strings = node.Key.Split('@');
+							if (strings[0] == "Slot")
+							{
+								var slot = Session.Slot.Deserialize(node.Value);
+								slots.Add(slot.PlayerReference, slot);
+							}
 						}
-					}
 
-					orderManager.LobbyInfo.Slots = slots;
-					Game.SyncLobbyInfo();
-					break;
-				}
+						orderManager.LobbyInfo.Slots = slots;
+						Game.SyncLobbyInfo();
+						break;
+					}
 
 				case "SyncLobbyGlobalSettings":
-				{
-					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
-					foreach (var node in nodes)
 					{
-						var strings = node.Key.Split('@');
-						if (strings[0] == "GlobalSettings")
-							orderManager.LobbyInfo.GlobalSettings = Session.Global.Deserialize(node.Value);
-					}
+						var nodes = MiniYaml.FromString(order.TargetString);
+						foreach (var node in nodes)
+						{
+							var strings = node.Key.Split('@');
+							if (strings[0] == "GlobalSettings")
+								orderManager.LobbyInfo.GlobalSettings = Session.Global.Deserialize(node.Value);
+						}
 
-					Game.SyncLobbyInfo();
-					break;
-				}
+						Game.SyncLobbyInfo();
+						break;
+					}
 
 				case "SyncConnectionQuality":
-				{
-					var nodes = MiniYaml.FromString(order.TargetString, order.OrderString);
-					foreach (var node in nodes)
 					{
-						var strings = node.Key.Split('@');
-						if (strings[0] == "ConnectionQuality")
+						var nodes = MiniYaml.FromString(order.TargetString);
+						foreach (var node in nodes)
 						{
-							var client = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.Index == Exts.ParseInt32Invariant(strings[1]));
-							if (client != null)
-								client.ConnectionQuality = FieldLoader.GetValue<Session.ConnectionQuality>("ConnectionQuality", node.Value.Value);
+							var strings = node.Key.Split('@');
+							if (strings[0] == "ConnectionQuality")
+							{
+								var client = orderManager.LobbyInfo.Clients.FirstOrDefault(c => c.Index == int.Parse(strings[1]));
+								if (client != null)
+									client.ConnectionQuality = FieldLoader.GetValue<Session.ConnectionQuality>("ConnectionQuality", node.Value.Value);
+							}
 						}
+
+						break;
 					}
 
-					break;
-				}
-
-				case "SyncMapPool":
-				{
-					orderManager.ServerMapPool = FieldLoader.GetValue<HashSet<string>>("SyncMapPool", order.TargetString);
-					break;
-				}
-
 				default:
-				{
-					if (world == null)
+					{
+						if (world == null)
+							break;
+
+						if (order.GroupedActors == null)
+							ResolveOrder(order, world, orderManager, clientId);
+						else
+							foreach (var subject in order.GroupedActors)
+								ResolveOrder(Order.FromGroupedOrder(order, subject), world, orderManager, clientId);
+
 						break;
-
-					if (order.GroupedActors == null)
-						ResolveOrder(order, world, orderManager, clientId);
-					else
-						foreach (var subject in order.GroupedActors)
-							ResolveOrder(Order.FromGroupedOrder(order, subject), world, orderManager, clientId);
-
-					break;
-				}
+					}
 			}
 		}
 

OpenRA.Game/ObjectCreator.cs

@@ -133,9 +133,9 @@ namespace OpenRA
 
 		public ConstructorInfo GetCtor(Type type)
 		{
-			const BindingFlags Flags = BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance;
-			var ctors = type.GetConstructors(Flags).Where(x => x.HasAttribute<UseCtorAttribute>()).ToList();
-			if (ctors.Count > 1)
+			var flags = BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Instance;
+			var ctors = type.GetConstructors(flags).Where(x => x.HasAttribute<UseCtorAttribute>());
+			if (ctors.Count() > 1)
 				throw new InvalidOperationException("ObjectCreator: UseCtor on multiple constructors; invalid.");
 			return ctors.FirstOrDefault();
 		}
@@ -152,8 +152,8 @@ namespace OpenRA
 			for (var i = 0; i < p.Length; i++)
 			{
 				var key = p[i].Name;
-				if (!args.TryGetValue(key, out var arg)) throw new InvalidOperationException($"ObjectCreator: key `{key}' not found");
-				a[i] = arg;
+				if (!args.ContainsKey(key)) throw new InvalidOperationException($"ObjectCreator: key `{key}' not found");
+				a[i] = args[key];
 			}
 
 			return ctor.Invoke(a);

OpenRA.Game/OpenRA.Game.csproj

@@ -10,10 +10,11 @@
     <PackageReference Include="System.Collections.Immutable" Version="6.0.0" />
   </ItemGroup>
   <ItemGroup>
-    <PackageReference Include="Linguini.Bundle" Version="0.6.0" />
+    <PackageReference Include="Linguini.Bundle" Version="0.5.0" />
     <PackageReference Include="OpenRA-Eluant" Version="1.0.22" />
     <PackageReference Include="Mono.NAT" Version="3.0.4" />
     <PackageReference Include="SharpZipLib" Version="1.4.2" />
+    <PackageReference Include="System.Net.Http" Version="4.3.4" />
     <PackageReference Include="System.Threading.Channels" Version="6.0.0" />
   </ItemGroup>
 </Project>

OpenRA.Game/Platform.cs

@@ -109,14 +109,14 @@ namespace OpenRA
 						var p = Process.Start(psi);
 						string line;
 						while ((line = p.StandardOutput.ReadLine()) != null)
-							if (line.StartsWith("Operating System: ", StringComparison.Ordinal))
+							if (line.StartsWith("Operating System: "))
 								return line[18..] + suffix;
 					}
 					catch { }
 
 					if (File.Exists("/etc/os-release"))
 						foreach (var line in File.ReadLines("/etc/os-release"))
-							if (line.StartsWith("PRETTY_NAME=", StringComparison.Ordinal))
+							if (line.StartsWith("PRETTY_NAME="))
 								return line[13..^1] + suffix;
 				}
 				else if (CurrentPlatform == PlatformType.OSX)
@@ -134,7 +134,7 @@ namespace OpenRA
 						while ((line = p.StandardOutput.ReadLine()) != null)
 						{
 							line = line.Trim();
-							if (line.StartsWith("System Version: ", StringComparison.Ordinal))
+							if (line.StartsWith("System Version: "))
 								return line[16..];
 						}
 					}
@@ -274,7 +274,7 @@ namespace OpenRA
 				throw new DirectoryNotFoundException(path);
 
 			if (!path.EndsWith(Path.DirectorySeparatorChar.ToString(), StringComparison.Ordinal) &&
-				!path.EndsWith(Path.AltDirectorySeparatorChar.ToString(), StringComparison.Ordinal))
+			    !path.EndsWith(Path.AltDirectorySeparatorChar.ToString(), StringComparison.Ordinal))
 				path += Path.DirectorySeparatorChar;
 
 			engineDirAccessed = true;

OpenRA.Game/Player.cs

@@ -133,7 +133,7 @@ namespace OpenRA
 
 		static FactionInfo ResolveDisplayFaction(World world, string factionName)
 		{
-			var factions = world.Map.Rules.Actors[SystemActors.World].TraitInfos<FactionInfo>();
+			var factions = world.Map.Rules.Actors[SystemActors.World].TraitInfos<FactionInfo>().ToArray();
 
 			return factions.FirstOrDefault(f => f.InternalName == factionName) ?? factions.First();
 		}

OpenRA.Game/PlayerDatabase.cs

@@ -9,6 +9,7 @@
  */
 #endregion
 
+using System.Linq;
 using System.Threading.Tasks;
 using OpenRA.FileFormats;
 using OpenRA.Graphics;
@@ -93,10 +94,10 @@ namespace OpenRA
 				});
 			}
 
-			var labelNode = yaml.NodeWithKeyOrDefault("Label");
-			var icon24Node = yaml.NodeWithKeyOrDefault("Icon24");
-			var icon48Node = yaml.NodeWithKeyOrDefault("Icon48");
-			var icon72Node = yaml.NodeWithKeyOrDefault("Icon72");
+			var labelNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Label");
+			var icon24Node = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon24");
+			var icon48Node = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon48");
+			var icon72Node = yaml.Nodes.FirstOrDefault(n => n.Key == "Icon72");
 			if (labelNode == null)
 				return null;
 

OpenRA.Game/PlayerProfile.cs

@@ -10,6 +10,7 @@
 #endregion
 
 using System.Collections.Generic;
+using System.Linq;
 
 namespace OpenRA
 {
@@ -30,7 +31,7 @@ namespace OpenRA
 		{
 			var badges = new List<PlayerBadge>();
 
-			var badgesNode = yaml.NodeWithKeyOrDefault("Badges");
+			var badgesNode = yaml.Nodes.FirstOrDefault(n => n.Key == "Badges");
 			if (badgesNode != null)
 			{
 				var playerDatabase = Game.ModData.Manifest.Get<PlayerDatabase>();

OpenRA.Game/Primitives/BitSet.cs

@@ -86,7 +86,7 @@ namespace OpenRA.Primitives
 
 		public static BitSet<T> FromStringsNoAlloc(string[] values)
 		{
-			return new BitSet<T>(BitSetAllocator<T>.GetBitsNoAlloc(values));
+			return new BitSet<T>(BitSetAllocator<T>.GetBitsNoAlloc(values)) { };
 		}
 
 		public override string ToString()

OpenRA.Game/Primitives/Color.cs

@@ -17,7 +17,7 @@ namespace OpenRA.Primitives
 {
 	public readonly struct Color : IEquatable<Color>, IScriptBindable
 	{
-		readonly uint argb;
+		readonly long argb;
 
 		public static Color FromArgb(int red, int green, int blue)
 		{
@@ -26,7 +26,7 @@ namespace OpenRA.Primitives
 
 		public static Color FromArgb(int alpha, int red, int green, int blue)
 		{
-			return new Color((uint)(((byte)alpha << 24) + ((byte)red << 16) + ((byte)green << 8) + (byte)blue));
+			return new Color(((byte)alpha << 24) + ((byte)red << 16) + ((byte)green << 8) + (byte)blue);
 		}
 
 		public static Color FromAhsl(int alpha, float h, float s, float l)
@@ -55,14 +55,14 @@ namespace OpenRA.Primitives
 			return (A, h, s, v);
 		}
 
-		Color(uint argb)
+		Color(long argb)
 		{
 			this.argb = argb;
 		}
 
-		public uint ToArgb()
+		public int ToArgb()
 		{
-			return argb;
+			return (int)argb;
 		}
 
 		public static Color FromArgb(int alpha, Color baseColor)
@@ -70,9 +70,14 @@ namespace OpenRA.Primitives
 			return FromArgb(alpha, baseColor.R, baseColor.G, baseColor.B);
 		}
 
+		public static Color FromArgb(int argb)
+		{
+			return FromArgb((byte)(argb >> 24), (byte)(argb >> 16), (byte)(argb >> 8), (byte)argb);
+		}
+
 		public static Color FromArgb(uint argb)
 		{
-			return new Color(argb);
+			return FromArgb((byte)(argb >> 24), (byte)(argb >> 16), (byte)(argb >> 8), (byte)argb);
 		}
 
 		static float SrgbToLinear(float c)
@@ -149,7 +154,7 @@ namespace OpenRA.Primitives
 
 			// Wrap negative values into [0-1)
 			if (h < 0)
-				h++;
+				h += 1;
 
 			var s = delta / rgbMax;
 			return (h, s, v);
@@ -164,12 +169,12 @@ namespace OpenRA.Primitives
 
 			byte alpha = 255;
 			if (!byte.TryParse(value.AsSpan(0, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var red)
-				|| !byte.TryParse(value.AsSpan(2, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var green)
-				|| !byte.TryParse(value.AsSpan(4, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var blue))
+			    || !byte.TryParse(value.AsSpan(2, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var green)
+			    || !byte.TryParse(value.AsSpan(4, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var blue))
 				return false;
 
 			if (value.Length == 8
-				&& !byte.TryParse(value.AsSpan(6, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out alpha))
+			    && !byte.TryParse(value.AsSpan(6, 2), NumberStyles.HexNumber, CultureInfo.InvariantCulture, out alpha))
 				return false;
 
 			color = FromArgb(alpha, red, green, blue);
@@ -219,9 +224,9 @@ namespace OpenRA.Primitives
 		public override string ToString()
 		{
 			if (A == 255)
-				return CryptoUtil.ToHex(stackalloc byte[3] { R, G, B });
+				return R.ToString("X2") + G.ToString("X2") + B.ToString("X2");
 
-			return CryptoUtil.ToHex(stackalloc byte[4] { R, G, B, A });
+			return R.ToString("X2") + G.ToString("X2") + B.ToString("X2") + A.ToString("X2");
 		}
 
 		public static Color Transparent => FromArgb(0x00FFFFFF);

OpenRA.Game/Primitives/LongBitSet.cs

@@ -99,7 +99,7 @@ namespace OpenRA.Primitives
 
 		public static LongBitSet<T> FromStringsNoAlloc(string[] values)
 		{
-			return new LongBitSet<T>(LongBitSetAllocator<T>.GetBitsNoAlloc(values));
+			return new LongBitSet<T>(LongBitSetAllocator<T>.GetBitsNoAlloc(values)) { };
 		}
 
 		public static void Reset()

OpenRA.Game/Primitives/Rectangle.cs

@@ -13,12 +13,13 @@ using System;
 
 namespace OpenRA.Primitives
 {
-	public readonly struct Rectangle : IEquatable<Rectangle>
+	public struct Rectangle : IEquatable<Rectangle>
 	{
-		public readonly int X;
-		public readonly int Y;
-		public readonly int Width;
-		public readonly int Height;
+		// TODO: Make these readonly: this will require a lot of changes to the UI logic
+		public int X;
+		public int Y;
+		public int Width;
+		public int Height;
 		public static readonly Rectangle Empty;
 
 		public static Rectangle FromLTRB(int left, int top, int right, int bottom)
@@ -57,35 +58,35 @@ namespace OpenRA.Primitives
 			Height = size.Height;
 		}
 
-		public readonly int Left => X;
-		public readonly int Right => X + Width;
-		public readonly int Top => Y;
-		public readonly int Bottom => Y + Height;
-		public readonly bool IsEmpty => X == 0 && Y == 0 && Width == 0 && Height == 0;
-		public readonly int2 Location => new(X, Y);
-		public readonly Size Size => new(Width, Height);
+		public int Left => X;
+		public int Right => X + Width;
+		public int Top => Y;
+		public int Bottom => Y + Height;
+		public bool IsEmpty => X == 0 && Y == 0 && Width == 0 && Height == 0;
+		public int2 Location => new(X, Y);
+		public Size Size => new(Width, Height);
 
-		public readonly int2 TopLeft => Location;
-		public readonly int2 TopRight => new(X + Width, Y);
-		public readonly int2 BottomLeft => new(X, Y + Height);
-		public readonly int2 BottomRight => new(X + Width, Y + Height);
+		public int2 TopLeft => Location;
+		public int2 TopRight => new(X + Width, Y);
+		public int2 BottomLeft => new(X, Y + Height);
+		public int2 BottomRight => new(X + Width, Y + Height);
 
-		public readonly bool Contains(int x, int y)
+		public bool Contains(int x, int y)
 		{
 			return x >= Left && x < Right && y >= Top && y < Bottom;
 		}
 
-		public readonly bool Contains(int2 pt)
+		public bool Contains(int2 pt)
 		{
 			return Contains(pt.X, pt.Y);
 		}
 
-		public readonly bool Equals(Rectangle other)
+		public bool Equals(Rectangle other)
 		{
 			return this == other;
 		}
 
-		public override readonly bool Equals(object obj)
+		public override bool Equals(object obj)
 		{
 			if (obj is not Rectangle)
 				return false;
@@ -93,17 +94,17 @@ namespace OpenRA.Primitives
 			return this == (Rectangle)obj;
 		}
 
-		public override readonly int GetHashCode()
+		public override int GetHashCode()
 		{
 			return Height + Width ^ X + Y;
 		}
 
-		public readonly bool IntersectsWith(Rectangle rect)
+		public bool IntersectsWith(Rectangle rect)
 		{
 			return Left < rect.Right && Right > rect.Left && Top < rect.Bottom && Bottom > rect.Top;
 		}
 
-		readonly bool IntersectsWithInclusive(Rectangle r)
+		bool IntersectsWithInclusive(Rectangle r)
 		{
 			return Left <= r.Right && Right >= r.Left && Top <= r.Bottom && Bottom >= r.Top;
 		}
@@ -116,14 +117,14 @@ namespace OpenRA.Primitives
 			return FromLTRB(Math.Max(a.Left, b.Left), Math.Max(a.Top, b.Top), Math.Min(a.Right, b.Right), Math.Min(a.Bottom, b.Bottom));
 		}
 
-		public readonly bool Contains(Rectangle rect)
+		public bool Contains(Rectangle rect)
 		{
 			return rect == Intersect(this, rect);
 		}
 
 		public static Rectangle operator *(int a, Rectangle b) { return new Rectangle(a * b.X, a * b.Y, a * b.Width, a * b.Height); }
 
-		public override readonly string ToString()
+		public override string ToString()
 		{
 			return $"{X},{Y},{Width},{Height}";
 		}

OpenRA.Game/Primitives/RingBuffer.cs

@@ -1,146 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright (c) The OpenRA Developers and Contributors
- * This file is part of OpenRA, which is free software. It is made
- * available to you under the terms of the GNU General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version. For more
- * information, see COPYING.
- */
-#endregion
-
-using System;
-using System.Collections.Generic;
-
-namespace OpenRA.Primitives
-{
-	/// <summary>Fixed size rorating buffer backed by an array.</summary>
-	public class RingBuffer<T> : ICollection<T>, IEnumerable<T>
-	{
-		readonly IComparer<T> comparer;
-		readonly T[] values;
-		int start;
-
-		public int Capacity => values.Length;
-		public int Count { get; private set; }
-		public bool IsReadOnly => false;
-
-		public RingBuffer(int capacity, IComparer<T> comparer)
-		{
-			this.comparer = comparer;
-			values = new T[capacity];
-			start = 0;
-			Count = 0;
-		}
-
-		public RingBuffer(int capacity)
-			: this(capacity, Comparer<T>.Default) { }
-
-		public void Add(T value)
-		{
-			values[(start + Count) % values.Length] = value;
-			if (Count < values.Length)
-				Count++;
-			else
-				start = (start + 1) % values.Length;
-		}
-
-		public void Clear()
-		{
-			Array.Clear(values, 0, values.Length);
-			start = 0;
-			Count = 0;
-		}
-
-		public bool Contains(T value)
-		{
-			var capacity = values.Length;
-			var end = start + Count;
-			for (var i = start; i < end; ++i)
-				if (comparer.Compare(values[i % capacity], value) == 0)
-					return true;
-
-			return false;
-		}
-
-		public void CopyTo(T[] array, int arrayIndex)
-		{
-			if (array == null)
-				throw new ArgumentNullException(nameof(array));
-
-			if (arrayIndex < 0)
-				throw new ArgumentNullException(nameof(arrayIndex));
-
-			if (arrayIndex + Count >= array.Length)
-				throw new ArgumentException("Invalid array capacity");
-
-			var destinationIndex = arrayIndex;
-			var end = start + Count;
-			var capacity = values.Length;
-			for (var i = start; i < end; ++i)
-				array[destinationIndex++] = values[i % capacity];
-		}
-
-		public bool Remove(T value)
-		{
-			var capacity = values.Length;
-			var end = start + Count;
-			for (var i = start; i < end; ++i)
-			{
-				if (comparer.Compare(values[i % capacity], value) == 0)
-				{
-					end--;
-					for (var j = i; j < end; ++j)
-						values[j % capacity] = values[(j + 1) % capacity];
-
-					Count--;
-					return true;
-				}
-			}
-
-			return false;
-		}
-
-		public T this[int pos]
-		{
-			get => values[(start + pos) % values.Length];
-
-			set
-			{
-				if (pos >= Count)
-					throw new ArgumentException($"Index out of bounds: {pos}");
-
-				values[(start + pos) % values.Length] = value;
-			}
-		}
-
-		public T First()
-		{
-			if (Count == 0)
-				throw new ArgumentException("Empty buffer");
-
-			return values[start];
-		}
-
-		public T Last()
-		{
-			if (Count == 0)
-				throw new ArgumentException("Empty buffer");
-
-			return values[(start + Count - 1) % values.Length];
-		}
-
-		public IEnumerator<T> GetEnumerator()
-		{
-			var initState = start + Count;
-			for (var i = 0; i < Count; i++)
-			{
-				if (start + Count != initState)
-					throw new InvalidOperationException("Collection was modified; enumeration operation may not execute");
-				yield return values[(start + i) % values.Length];
-			}
-		}
-
-		System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator() { return GetEnumerator(); }
-	}
-}

OpenRA.Game/Primitives/TypeDictionary.cs

@@ -12,20 +12,14 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace OpenRA.Primitives
 {
 	public class TypeDictionary : IEnumerable<object>
 	{
-		static readonly Func<Type, ITypeContainer> CreateTypeContainer = t =>
-			(ITypeContainer)typeof(TypeContainer<>).MakeGenericType(t).GetConstructor(Type.EmptyTypes).Invoke(null);
-
-		readonly Dictionary<Type, ITypeContainer> data = new();
-
-		ITypeContainer InnerGet(Type t)
-		{
-			return data.GetOrAdd(t, CreateTypeContainer);
-		}
+		static readonly Func<Type, List<object>> CreateList = type => new List<object>();
+		readonly Dictionary<Type, List<object>> data = new();
 
 		public void Add(object val)
 		{
@@ -39,7 +33,7 @@ namespace OpenRA.Primitives
 
 		void InnerAdd(Type t, object val)
 		{
-			InnerGet(t).Add(val);
+			data.GetOrAdd(t, CreateList).Add(val);
 		}
 
 		public bool Contains<T>()
@@ -54,33 +48,35 @@ namespace OpenRA.Primitives
 
 		public T Get<T>()
 		{
-			return Get<T>(true);
+			return (T)Get(typeof(T), true);
 		}
 
 		public T GetOrDefault<T>()
 		{
-			return Get<T>(false);
+			var result = Get(typeof(T), false);
+			if (result == null)
+				return default;
+			return (T)result;
 		}
 
-		T Get<T>(bool throwsIfMissing)
+		object Get(Type t, bool throwsIfMissing)
 		{
-			if (!data.TryGetValue(typeof(T), out var container))
+			if (!data.TryGetValue(t, out var ret))
 			{
 				if (throwsIfMissing)
-					throw new InvalidOperationException($"TypeDictionary does not contain instance of type `{typeof(T)}`");
-				return default;
+					throw new InvalidOperationException($"TypeDictionary does not contain instance of type `{t}`");
+				return null;
 			}
 
-			var list = ((TypeContainer<T>)container).Objects;
-			if (list.Count > 1)
-				throw new InvalidOperationException($"TypeDictionary contains multiple instances of type `{typeof(T)}`");
-			return list[0];
+			if (ret.Count > 1)
+				throw new InvalidOperationException($"TypeDictionary contains multiple instances of type `{t}`");
+			return ret[0];
 		}
 
-		public IReadOnlyCollection<T> WithInterface<T>()
+		public IEnumerable<T> WithInterface<T>()
 		{
-			if (data.TryGetValue(typeof(T), out var container))
-				return ((TypeContainer<T>)container).Objects;
+			if (data.TryGetValue(typeof(T), out var objs))
+				return objs.Cast<T>();
 			return Array.Empty<T>();
 		}
 
@@ -96,19 +92,18 @@ namespace OpenRA.Primitives
 
 		void InnerRemove(Type t, object val)
 		{
-			if (!data.TryGetValue(t, out var container))
+			if (!data.TryGetValue(t, out var objs))
 				return;
-
-			container.Remove(val);
-			if (container.Count == 0)
+			objs.Remove(val);
+			if (objs.Count == 0)
 				data.Remove(t);
 		}
 
 		public void TrimExcess()
 		{
 			data.TrimExcess();
-			foreach (var t in data.Keys)
-				InnerGet(t).TrimExcess();
+			foreach (var objs in data.Values)
+				objs.TrimExcess();
 		}
 
 		public IEnumerator<object> GetEnumerator()
@@ -120,36 +115,6 @@ namespace OpenRA.Primitives
 		{
 			return GetEnumerator();
 		}
-
-		interface ITypeContainer
-		{
-			int Count { get; }
-			void Add(object value);
-			void Remove(object value);
-			void TrimExcess();
-		}
-
-		sealed class TypeContainer<T> : ITypeContainer
-		{
-			public List<T> Objects { get; } = new List<T>();
-
-			public int Count => Objects.Count;
-
-			public void Add(object value)
-			{
-				Objects.Add((T)value);
-			}
-
-			public void Remove(object value)
-			{
-				Objects.Remove((T)value);
-			}
-
-			public void TrimExcess()
-			{
-				Objects.TrimExcess();
-			}
-		}
 	}
 
 	public static class TypeExts

OpenRA.Game/Renderer.cs

@@ -27,7 +27,7 @@ namespace OpenRA
 		public SpriteRenderer WorldSpriteRenderer { get; }
 		public RgbaSpriteRenderer WorldRgbaSpriteRenderer { get; }
 		public RgbaColorRenderer WorldRgbaColorRenderer { get; }
-		public IRenderer[] WorldRenderers = Array.Empty<IRenderer>();
+		public ModelRenderer WorldModelRenderer { get; }
 		public RgbaColorRenderer RgbaColorRenderer { get; }
 		public SpriteRenderer SpriteRenderer { get; }
 		public RgbaSpriteRenderer RgbaSpriteRenderer { get; }
@@ -41,13 +41,10 @@ namespace OpenRA
 		internal IGraphicsContext Context { get; }
 
 		internal int SheetSize { get; }
-		internal int TempVertexBufferSize { get; }
-		internal int TempIndexBufferSize { get; }
+		internal int TempBufferSize { get; }
 
-		readonly IVertexBuffer<Vertex> tempVertexBuffer;
-		readonly IIndexBuffer quadIndexBuffer;
+		readonly IVertexBuffer<Vertex> tempBuffer;
 		readonly Stack<Rectangle> scissorState = new();
-		readonly ITexture worldBufferSnapshot;
 
 		IFrameBuffer screenBuffer;
 		Sprite screenSprite;
@@ -61,15 +58,6 @@ namespace OpenRA
 		public Size WorldFrameBufferSize => worldSheet.Size;
 		public int WorldDownscaleFactor { get; private set; } = 1;
 
-		/// <summary>
-		/// Copies and returns the currently rendered world state as a temporary texture.
-		/// </summary>
-		public ITexture WorldBufferSnapshot()
-		{
-			worldBufferSnapshot.SetDataFromReadBuffer(new Rectangle(int2.Zero, worldSheet.Size));
-			return worldBufferSnapshot;
-		}
-
 		SheetBuilder fontSheetBuilder;
 		readonly IPlatform platform;
 
@@ -87,28 +75,24 @@ namespace OpenRA
 			this.platform = platform;
 			var resolution = GetResolution(graphicSettings);
 
-			TempVertexBufferSize = graphicSettings.BatchSize - graphicSettings.BatchSize % 4;
-			TempIndexBufferSize = TempVertexBufferSize / 4 * 6;
-
 			Window = platform.CreateWindow(new Size(resolution.Width, resolution.Height),
-				graphicSettings.Mode, graphicSettings.UIScale, TempVertexBufferSize, TempIndexBufferSize,
-				graphicSettings.VideoDisplay, graphicSettings.GLProfile);
+				graphicSettings.Mode, graphicSettings.UIScale, graphicSettings.BatchSize,
+				graphicSettings.VideoDisplay, graphicSettings.GLProfile, !graphicSettings.DisableLegacyGL);
 
 			Context = Window.Context;
 
+			TempBufferSize = graphicSettings.BatchSize;
 			SheetSize = graphicSettings.SheetSize;
 
-			var combinedBindings = new CombinedShaderBindings();
-			WorldSpriteRenderer = new SpriteRenderer(this, Context.CreateShader(combinedBindings));
+			WorldSpriteRenderer = new SpriteRenderer(this, Context.CreateShader("combined"));
 			WorldRgbaSpriteRenderer = new RgbaSpriteRenderer(WorldSpriteRenderer);
 			WorldRgbaColorRenderer = new RgbaColorRenderer(WorldSpriteRenderer);
-			SpriteRenderer = new SpriteRenderer(this, Context.CreateShader(combinedBindings));
+			WorldModelRenderer = new ModelRenderer(this, Context.CreateShader("model"));
+			SpriteRenderer = new SpriteRenderer(this, Context.CreateShader("combined"));
 			RgbaSpriteRenderer = new RgbaSpriteRenderer(SpriteRenderer);
 			RgbaColorRenderer = new RgbaColorRenderer(SpriteRenderer);
 
-			tempVertexBuffer = Context.CreateVertexBuffer<Vertex>(TempVertexBufferSize);
-			quadIndexBuffer = Context.CreateIndexBuffer(Util.CreateQuadIndices(TempIndexBufferSize / 6));
-			worldBufferSnapshot = Context.CreateTexture();
+			tempBuffer = Context.CreateVertexBuffer(TempBufferSize);
 		}
 
 		static Size GetResolution(GraphicSettings graphicsSettings)
@@ -269,6 +253,8 @@ namespace OpenRA
 			if (lastWorldViewport != worldViewport)
 			{
 				WorldSpriteRenderer.SetViewportParams(worldSheet.Size, WorldDownscaleFactor, depthMargin, worldViewport.Location);
+				WorldModelRenderer.SetViewportParams();
+
 				lastWorldViewport = worldViewport;
 			}
 
@@ -314,11 +300,9 @@ namespace OpenRA
 			Flush();
 			currentPaletteTexture = palette.Texture;
 
-			SpriteRenderer.SetPalette(palette);
-			WorldSpriteRenderer.SetPalette(palette);
-
-			foreach (var r in WorldRenderers)
-				r.SetPalette(palette);
+			SpriteRenderer.SetPalette(currentPaletteTexture, palette.ColorShifts);
+			WorldSpriteRenderer.SetPalette(currentPaletteTexture, palette.ColorShifts);
+			WorldModelRenderer.SetPalette(currentPaletteTexture);
 		}
 
 		public void EndFrame(IInputHandler inputHandler)
@@ -342,32 +326,27 @@ namespace OpenRA
 			renderType = RenderType.None;
 		}
 
-		public void DrawBatch<T>(IVertexBuffer<T> vertices, IShader shader,
+		public void DrawBatch(Vertex[] vertices, int numVertices, PrimitiveType type)
+		{
+			tempBuffer.SetData(vertices, numVertices);
+			DrawBatch(tempBuffer, 0, numVertices, type);
+		}
+
+		public void DrawBatch(ref Vertex[] vertices, int numVertices, PrimitiveType type)
+		{
+			tempBuffer.SetData(ref vertices, numVertices);
+			DrawBatch(tempBuffer, 0, numVertices, type);
+		}
+
+		public void DrawBatch<T>(IVertexBuffer<T> vertices,
 			int firstVertex, int numVertices, PrimitiveType type)
 			where T : struct
 		{
 			vertices.Bind();
-			shader.Bind();
 			Context.DrawPrimitives(type, firstVertex, numVertices);
 			PerfHistory.Increment("batches", 1);
 		}
 
-		public void DrawQuadBatch(ref Vertex[] vertices, IShader shader, int numVertices)
-		{
-			tempVertexBuffer.SetData(ref vertices, numVertices);
-			DrawQuadBatch(tempVertexBuffer, quadIndexBuffer, shader, numVertices / 4 * 6, 0);
-		}
-
-		public void DrawQuadBatch<T>(IVertexBuffer<T> vertices, IIndexBuffer indices, IShader shader, int numIndices, int start)
-			where T : struct
-		{
-			vertices.Bind();
-			indices.Bind();
-			shader.Bind();
-			Context.DrawElements(numIndices, start);
-			PerfHistory.Increment("batches", 1);
-		}
-
 		public void Flush()
 		{
 			CurrentBatchRenderer = null;
@@ -395,19 +374,9 @@ namespace OpenRA
 			}
 		}
 
-		public IFrameBuffer CreateFrameBuffer(Size s)
+		public IVertexBuffer<Vertex> CreateVertexBuffer(int length)
 		{
-			return Context.CreateFrameBuffer(s);
-		}
-
-		public IShader CreateShader(IShaderBindings bindings)
-		{
-			return Context.CreateShader(bindings);
-		}
-
-		public IVertexBuffer<T> CreateVertexBuffer<T>(int length) where T : struct
-		{
-			return Context.CreateVertexBuffer<T>(length);
+			return Context.CreateVertexBuffer(length);
 		}
 
 		public void EnableScissor(Rectangle rect)
@@ -534,11 +503,8 @@ namespace OpenRA
 
 		public void Dispose()
 		{
-			worldBuffer?.Dispose();
-			screenBuffer.Dispose();
-			worldBufferSnapshot.Dispose();
-			tempVertexBuffer.Dispose();
-			quadIndexBuffer.Dispose();
+			WorldModelRenderer.Dispose();
+			tempBuffer.Dispose();
 			fontSheetBuilder?.Dispose();
 			if (Fonts != null)
 				foreach (var font in Fonts.Values)

OpenRA.Game/Scripting/ScriptContext.cs

@@ -74,17 +74,14 @@ namespace OpenRA.Scripting
 	/// Provides global bindings in Lua code.
 	/// </summary>
 	/// <remarks>
-	/// <para>
 	/// Instance methods and properties declared in derived classes will be made available in Lua. Use
 	/// <see cref="ScriptGlobalAttribute"/> on your derived class to specify the name exposed in Lua. It is recommended
 	/// to apply <see cref="DescAttribute"/> against each method or property to provide a description of what it does.
-	/// </para>
-	/// <para>
+	///
 	/// Any parameters to your method that are <see cref="LuaValue"/>s will be disposed automatically when your method
 	/// completes. If you need to return any of these values, or need them to live longer than your method, you must
 	/// use <see cref="LuaValue.CopyReference"/> to get your own copy of the value. Any copied values you return will
 	/// be disposed automatically, but you assume responsibility for disposing any other copies.
-	/// </para>
 	/// </remarks>
 	public abstract class ScriptGlobal : ScriptObjectWrapper
 	{
@@ -102,7 +99,7 @@ namespace OpenRA.Scripting
 			if (names.Length != 1)
 				throw new InvalidOperationException($"[ScriptGlobal] attribute not found for global table '{type}'");
 
-			Name = names[0].Name;
+			Name = names.First().Name;
 			Bind(new[] { this });
 		}
 
@@ -114,7 +111,7 @@ namespace OpenRA.Scripting
 				{
 					using (var luaObject = a.ToLuaValue(Context))
 					using (var filterResult = filter.Call(luaObject))
-					using (var result = filterResult[0])
+					using (var result = filterResult.First())
 						return result.ToBoolean();
 				});
 			}
@@ -214,7 +211,7 @@ namespace OpenRA.Scripting
 				var ctor = b.GetConstructors(BindingFlags.Public | BindingFlags.Instance).FirstOrDefault(c =>
 				{
 					var p = c.GetParameters();
-					return p.Length == 1 && p[0].ParameterType == typeof(ScriptContext);
+					return p.Length == 1 && p.First().ParameterType == typeof(ScriptContext);
 				});
 
 				if (ctor == null)

OpenRA.Game/Scripting/ScriptMemberWrapper.cs

@@ -125,8 +125,8 @@ namespace OpenRA.Scripting
 		public static IEnumerable<MemberInfo> WrappableMembers(Type t)
 		{
 			// Only expose defined public non-static methods that were explicitly declared by the author
-			const BindingFlags Flags = BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly;
-			foreach (var mi in t.GetMembers(Flags))
+			var flags = BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly;
+			foreach (var mi in t.GetMembers(flags))
 			{
 				// Properties are always wrappable
 				if (mi is PropertyInfo)
@@ -150,7 +150,7 @@ namespace OpenRA.Scripting
 			// Remove the namespace and the trailing "Info"
 			return types.SelectMany(i => i.GetGenericArguments())
 				.Select(g => g.Name.Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries).LastOrDefault())
-				.Select(s => s.EndsWith("Info", StringComparison.Ordinal) ? s.Remove(s.Length - 4, 4) : s)
+				.Select(s => s.EndsWith("Info") ? s.Remove(s.Length - 4, 4) : s)
 				.ToArray();
 		}
 	}

OpenRA.Game/Scripting/ScriptTypes.cs

@@ -40,10 +40,13 @@ namespace OpenRA.Scripting
 				t = nullable;
 
 			// Value wraps a CLR object
-			if (value.TryGetClrObject(out var temp) && temp.GetType() == t)
+			if (value.TryGetClrObject(out var temp))
 			{
-				clrObject = temp;
-				return true;
+				if (temp.GetType() == t)
+				{
+					clrObject = temp;
+					return true;
+				}
 			}
 
 			if (value is LuaNil && !t.IsValueType)

OpenRA.Game/SelectableExts.cs

@@ -62,7 +62,10 @@ namespace OpenRA.Traits
 
 		public static Actor WithHighestSelectionPriority(this IEnumerable<ActorBoundsPair> actors, int2 selectionPixel, Modifiers modifiers)
 		{
-			return actors.MaxByOrDefault(a => CalculateActorSelectionPriority(a.Actor.Info, a.Bounds, selectionPixel, modifiers)).Actor;
+			if (!actors.Any())
+				return null;
+
+			return actors.MaxBy(a => CalculateActorSelectionPriority(a.Actor.Info, a.Bounds, selectionPixel, modifiers)).Actor;
 		}
 
 		public static FrozenActor WithHighestSelectionPriority(this IEnumerable<FrozenActor> actors, int2 selectionPixel, Modifiers modifiers)

OpenRA.Game/Server/Connection.cs

@@ -60,11 +60,11 @@ namespace OpenRA.Server
 		static byte[] CreatePingFrame()
 		{
 			var ms = new MemoryStream(21);
-			ms.Write(13);
-			ms.Write(0);
-			ms.Write(0);
+			ms.WriteArray(BitConverter.GetBytes(13));
+			ms.WriteArray(BitConverter.GetBytes(0));
+			ms.WriteArray(BitConverter.GetBytes(0));
 			ms.WriteByte((byte)OrderType.Ping);
-			ms.Write(Game.RunTime);
+			ms.WriteArray(BitConverter.GetBytes(Game.RunTime));
 			return ms.GetBuffer();
 		}
 
@@ -115,7 +115,7 @@ namespace OpenRA.Server
 									frame = BitConverter.ToInt32(bytes, 4);
 									state = ReceiveState.Data;
 
-									if (expectLength < 0 || (server.IsMultiplayer && expectLength > MaxOrderLength))
+									if (expectLength < 0 || (server.Type != ServerType.Local && expectLength > MaxOrderLength))
 									{
 										Log.Write("server", $"Closing socket connection to {EndPoint} because of excessive order length: {expectLength}");
 										return;
@@ -153,8 +153,9 @@ namespace OpenRA.Server
 						return;
 
 					// Regularly check player ping
-					if (lastPingSent.ElapsedMilliseconds > 1000 && TrySendData(CreatePingFrame()))
-						lastPingSent.Restart();
+					if (lastPingSent.ElapsedMilliseconds > 1000)
+						if (TrySendData(CreatePingFrame()))
+							lastPingSent.Restart();
 
 					// Send all data immediately, we will block again on read
 					while (sendQueue.TryTake(out var data, 0))

OpenRA.Game/Server/OrderBuffer.cs

@@ -68,7 +68,7 @@ namespace OpenRA.Server
 			ticksPerInterval = Interval / timestep;
 
 			this.players = players.ToList();
-			baselinePlayer = this.players[0];
+			baselinePlayer = this.players.First();
 
 			foreach (var player in this.players)
 			{
@@ -128,7 +128,7 @@ namespace OpenRA.Server
 			players.Remove(player);
 			if (player == baselinePlayer && players.Count > 0)
 			{
-				var newBaseline = players[0];
+				var newBaseline = players.First();
 				Interlocked.Exchange(ref baselinePlayer, newBaseline);
 			}
 

OpenRA.Game/Server/ProtocolVersion.cs

@@ -77,6 +77,6 @@ namespace OpenRA.Server
 		// The protocol for server and world orders
 		// This applies after the handshake has completed, and is provided to support
 		// alternative server implementations that wish to support multiple versions in parallel
-		public const int Orders = 21;
+		public const int Orders = 20;
 	}
 }

OpenRA.Game/Server/Server.cs

@@ -40,9 +40,8 @@ namespace OpenRA.Server
 	public enum ServerType
 	{
 		Local = 0,
-		Skirmish = 1,
-		Multiplayer = 2,
-		Dedicated = 3
+		Multiplayer = 1,
+		Dedicated = 2
 	}
 
 	public sealed class Server
@@ -118,7 +117,6 @@ namespace OpenRA.Server
 
 		public readonly MersenneTwister Random = new();
 		public readonly ServerType Type;
-		public bool IsMultiplayer => Type == ServerType.Dedicated || Type == ServerType.Multiplayer;
 
 		public readonly List<Connection> Conns = new();
 
@@ -130,8 +128,7 @@ namespace OpenRA.Server
 		// Managed by LobbyCommands
 		public MapPreview Map;
 		public readonly MapStatusCache MapStatusCache;
-		public GameSave GameSave;
-		public HashSet<string> MapPool;
+		public GameSave GameSave = null;
 
 		// Default to the next frame for ServerType.Local - MP servers take the value from the selected GameSpeed.
 		public int OrderLatency = 1;
@@ -250,9 +247,12 @@ namespace OpenRA.Server
 					{
 						listener.Server.SetSocketOption(SocketOptionLevel.IPv6, SocketOptionName.IPv6Only, 1);
 					}
-					catch (Exception ex) when (ex is SocketException || ex is ArgumentException)
+					catch (Exception ex)
 					{
-						Log.Write("server", $"Failed to set socket option on {endpoint}: {ex.Message}");
+						if (ex is SocketException || ex is ArgumentException)
+							Log.Write("server", $"Failed to set socket option on {endpoint}: {ex.Message}");
+						else
+							throw;
 					}
 
 					listener.Start();
@@ -282,8 +282,7 @@ namespace OpenRA.Server
 								}
 							}
 						}
-					})
-					{ Name = $"Connection listener ({listener.LocalEndpoint})", IsBackground = true }.Start();
+					}) { Name = $"Connection listener ({listener.LocalEndpoint})", IsBackground = true }.Start();
 				}
 				catch (SocketException ex)
 				{
@@ -306,10 +305,10 @@ namespace OpenRA.Server
 
 			randomSeed = (int)DateTime.Now.ToBinary();
 
-			if (IsMultiplayer && settings.EnableGeoIP)
+			if (type != ServerType.Local && settings.EnableGeoIP)
 				GeoIP.Initialize();
 
-			if (IsMultiplayer)
+			if (type != ServerType.Local)
 				Nat.TryForwardPort(Settings.ListenPort, Settings.ListenPort);
 
 			foreach (var trait in modData.Manifest.ServerTraits)
@@ -317,6 +316,7 @@ namespace OpenRA.Server
 
 			serverTraits.TrimExcess();
 
+			Map = ModData.MapCache[settings.Map];
 			MapStatusCache = new MapStatusCache(modData, MapStatusChanged, type == ServerType.Dedicated && settings.EnableLintChecks);
 
 			playerMessageTracker = new PlayerMessageTracker(this, DispatchOrdersToClient, SendLocalizedMessageTo);
@@ -327,6 +327,8 @@ namespace OpenRA.Server
 				GlobalSettings =
 				{
 					RandomSeed = randomSeed,
+					Map = Map.Uid,
+					MapStatus = Session.MapStatus.Unknown,
 					ServerName = settings.Name,
 					EnableSingleplayer = settings.EnableSingleplayer || Type != ServerType.Dedicated,
 					EnableSyncReports = settings.EnableSyncReports,
@@ -346,7 +348,8 @@ namespace OpenRA.Server
 
 			new Thread(_ =>
 			{
-				// Note: at least one of these is required to set the initial LobbyInfo.Map and MapStatus
+				// Initial status is set off the main thread to avoid triggering a load screen when joining a skirmish game
+				LobbyInfo.GlobalSettings.MapStatus = MapStatusCache[Map];
 				foreach (var t in serverTraits.WithInterface<INotifyServerStart>())
 					t.ServerStarted(this);
 
@@ -383,7 +386,7 @@ namespace OpenRA.Server
 					if (State == ServerState.ShuttingDown)
 					{
 						EndGame();
-						if (IsMultiplayer)
+						if (type != ServerType.Local)
 							Nat.TryRemovePortForward();
 						break;
 					}
@@ -436,8 +439,8 @@ namespace OpenRA.Server
 			{
 				// Send handshake and client index.
 				var ms = new MemoryStream(8);
-				ms.Write(ProtocolVersion.Handshake);
-				ms.Write(newConn.PlayerIndex);
+				ms.WriteArray(BitConverter.GetBytes(ProtocolVersion.Handshake));
+				ms.WriteArray(BitConverter.GetBytes(newConn.PlayerIndex));
 				newConn.TrySendData(ms.ToArray());
 
 				// Dispatch a handshake order
@@ -463,7 +466,7 @@ namespace OpenRA.Server
 			Conns.Add(newConn);
 		}
 
-		void ValidateClient(Connection newConn, string data, string name)
+		void ValidateClient(Connection newConn, string data)
 		{
 			try
 			{
@@ -476,7 +479,7 @@ namespace OpenRA.Server
 					return;
 				}
 
-				var handshake = HandshakeResponse.Deserialize(data, name);
+				var handshake = HandshakeResponse.Deserialize(data);
 
 				if (!string.IsNullOrEmpty(Settings.Password) && handshake.Password != Settings.Password)
 				{
@@ -491,7 +494,7 @@ namespace OpenRA.Server
 				{
 					Name = OpenRA.Settings.SanitizedPlayerName(handshake.Client.Name),
 					IPAddress = ipAddress.ToString(),
-					AnonymizedIPAddress = IsMultiplayer && Settings.ShareAnonymizedIPs ? Session.AnonymizeIP(ipAddress) : null,
+					AnonymizedIPAddress = Type != ServerType.Local && Settings.ShareAnonymizedIPs ? Session.AnonymizeIP(ipAddress) : null,
 					Location = GeoIP.LookupCountry(ipAddress),
 					Index = newConn.PlayerIndex,
 					PreferredColor = handshake.Client.PreferredColor,
@@ -580,7 +583,8 @@ namespace OpenRA.Server
 
 						Log.Write("server", $"{client.Name} ({newConn.EndPoint}) has joined the game.");
 
-						SendLocalizedMessage(Joined, Translation.Arguments("player", client.Name));
+						if (Type != ServerType.Local)
+							SendLocalizedMessage(Joined, Translation.Arguments("player", client.Name));
 
 						if (Type == ServerType.Dedicated)
 						{
@@ -603,7 +607,7 @@ namespace OpenRA.Server
 					}
 				}
 
-				if (!IsMultiplayer)
+				if (Type == ServerType.Local)
 				{
 					// Local servers can only be joined by the local client, so we can trust their identity without validation
 					client.Fingerprint = handshake.Fingerprint;
@@ -618,11 +622,10 @@ namespace OpenRA.Server
 						try
 						{
 							var httpClient = HttpClientFactory.Create();
-							var url = playerDatabase.Profile + handshake.Fingerprint;
-							var httpResponseMessage = await httpClient.GetAsync(url);
+							var httpResponseMessage = await httpClient.GetAsync(playerDatabase.Profile + handshake.Fingerprint);
 							var result = await httpResponseMessage.Content.ReadAsStreamAsync();
 
-							var yaml = MiniYaml.FromStream(result, url).First();
+							var yaml = MiniYaml.FromStream(result).First();
 							if (yaml.Key == "Player")
 							{
 								profile = FieldLoader.Load<PlayerProfile>(yaml.Value);
@@ -705,19 +708,19 @@ namespace OpenRA.Server
 		static byte[] CreateFrame(int client, int frame, byte[] data)
 		{
 			var ms = new MemoryStream(data.Length + 12);
-			ms.Write(data.Length + 4);
-			ms.Write(client);
-			ms.Write(frame);
-			ms.Write(data);
+			ms.WriteArray(BitConverter.GetBytes(data.Length + 4));
+			ms.WriteArray(BitConverter.GetBytes(client));
+			ms.WriteArray(BitConverter.GetBytes(frame));
+			ms.WriteArray(data);
 			return ms.GetBuffer();
 		}
 
 		static byte[] CreateAckFrame(int frame, byte count)
 		{
 			var ms = new MemoryStream(14);
-			ms.Write(6);
-			ms.Write(0);
-			ms.Write(frame);
+			ms.WriteArray(BitConverter.GetBytes(6));
+			ms.WriteArray(BitConverter.GetBytes(0));
+			ms.WriteArray(BitConverter.GetBytes(frame));
 			ms.WriteByte((byte)OrderType.Ack);
 			ms.WriteByte(count);
 			return ms.GetBuffer();
@@ -726,9 +729,9 @@ namespace OpenRA.Server
 		static byte[] CreateTickScaleFrame(float scale)
 		{
 			var ms = new MemoryStream(17);
-			ms.Write(9);
-			ms.Write(0);
-			ms.Write(0);
+			ms.WriteArray(BitConverter.GetBytes(9));
+			ms.WriteArray(BitConverter.GetBytes(0));
+			ms.WriteArray(BitConverter.GetBytes(0));
 			ms.WriteByte((byte)OrderType.TickScale);
 			ms.Write(scale);
 			return ms.GetBuffer();
@@ -877,13 +880,13 @@ namespace OpenRA.Server
 
 		public void DispatchServerOrdersToClients(byte[] data, int frame = 0)
 		{
-			const int From = 0;
-			var frameData = CreateFrame(From, frame, data);
+			var from = 0;
+			var frameData = CreateFrame(from, frame, data);
 			foreach (var c in Conns.ToList())
 				if (c.Validated)
-					DispatchFrameToClient(c, From, frameData);
+					DispatchFrameToClient(c, from, frameData);
 
-			RecordOrder(frame, data, From);
+			RecordOrder(frame, data, from);
 		}
 
 		public void ReceiveOrders(Connection conn, int frame, byte[] data)
@@ -969,7 +972,7 @@ namespace OpenRA.Server
 
 		void WriteLineWithTimeStamp(string line)
 		{
-			Console.WriteLine($"[{DateTime.Now.ToString(Settings.TimestampFormat, CultureInfo.CurrentCulture)}] {line}");
+			Console.WriteLine($"[{DateTime.Now.ToString(Settings.TimestampFormat)}] {line}");
 		}
 
 		void InterpretServerOrder(Connection conn, Order o)
@@ -981,7 +984,7 @@ namespace OpenRA.Server
 				if (!conn.Validated)
 				{
 					if (o.OrderString == "HandshakeResponse")
-						ValidateClient(conn, o.TargetString, o.OrderString);
+						ValidateClient(conn, o.TargetString);
 					else
 					{
 						Log.Write("server", $"Rejected connection from {conn.EndPoint}; Order `{o.OrderString}` is not a `HandshakeResponse`.");
@@ -994,39 +997,70 @@ namespace OpenRA.Server
 				switch (o.OrderString)
 				{
 					case "Command":
-					{
-						if (!InterpretCommand(o.TargetString, conn))
 						{
-							Log.Write("server", $"Unknown server command: {o.TargetString}");
-							SendLocalizedMessageTo(conn, UnknownServerCommand, Translation.Arguments("command", o.TargetString));
-						}
+							var handledBy = serverTraits.WithInterface<IInterpretCommand>()
+								.FirstOrDefault(t => t.InterpretCommand(this, conn, GetClient(conn), o.TargetString));
 
-						break;
-					}
+							if (handledBy == null)
+							{
+								Log.Write("server", $"Unknown server command: {o.TargetString}");
+								SendLocalizedMessageTo(conn, UnknownServerCommand, Translation.Arguments("command", o.TargetString));
+							}
+
+							break;
+						}
 
 					case "Chat":
-					{
-						if (!IsMultiplayer || !playerMessageTracker.IsPlayerAtFloodLimit(conn))
-							DispatchOrdersToClients(conn, 0, o.Serialize());
-
-						break;
-					}
-
-					case "GameSaveTraitData":
-					{
-						if (GameSave != null)
 						{
-							var data = MiniYaml.FromString(o.TargetString, o.OrderString)[0];
-							GameSave.AddTraitData(OpenRA.Exts.ParseInt32Invariant(data.Key), data.Value);
+							if (Type == ServerType.Local || !playerMessageTracker.IsPlayerAtFloodLimit(conn))
+								DispatchOrdersToClients(conn, 0, o.Serialize());
+
+							break;
 						}
 
-						break;
-					}
+					case "GameSaveTraitData":
+						{
+							if (GameSave != null)
+							{
+								var data = MiniYaml.FromString(o.TargetString)[0];
+								GameSave.AddTraitData(int.Parse(data.Key), data.Value);
+							}
+
+							break;
+						}
 
 					case "CreateGameSave":
-					{
-						if (GameSave != null)
 						{
+							if (GameSave != null)
+							{
+								// Sanitize potentially malicious input
+								var filename = o.TargetString;
+								var invalidIndex = -1;
+								var invalidChars = Path.GetInvalidFileNameChars();
+								while ((invalidIndex = filename.IndexOfAny(invalidChars)) != -1)
+									filename = filename.Remove(invalidIndex, 1);
+
+								var baseSavePath = Path.Combine(
+									Platform.SupportDir,
+									"Saves",
+									ModData.Manifest.Id,
+									ModData.Manifest.Metadata.Version);
+
+								if (!Directory.Exists(baseSavePath))
+									Directory.CreateDirectory(baseSavePath);
+
+								GameSave.Save(Path.Combine(baseSavePath, filename));
+								DispatchServerOrdersToClients(Order.FromTargetString("GameSaved", filename, true));
+							}
+
+							break;
+						}
+
+					case "LoadGameSave":
+						{
+							if (Type == ServerType.Dedicated || State >= ServerState.GameStarted)
+								break;
+
 							// Sanitize potentially malicious input
 							var filename = o.TargetString;
 							var invalidIndex = -1;
@@ -1034,90 +1068,62 @@ namespace OpenRA.Server
 							while ((invalidIndex = filename.IndexOfAny(invalidChars)) != -1)
 								filename = filename.Remove(invalidIndex, 1);
 
-							var baseSavePath = Path.Combine(
+							var savePath = Path.Combine(
 								Platform.SupportDir,
 								"Saves",
 								ModData.Manifest.Id,
-								ModData.Manifest.Metadata.Version);
+								ModData.Manifest.Metadata.Version,
+								filename);
 
-							if (!Directory.Exists(baseSavePath))
-								Directory.CreateDirectory(baseSavePath);
+							GameSave = new GameSave(savePath);
+							LobbyInfo.GlobalSettings = GameSave.GlobalSettings;
+							LobbyInfo.Slots = GameSave.Slots;
 
-							GameSave.Save(Path.Combine(baseSavePath, filename));
-							DispatchServerOrdersToClients(Order.FromTargetString("GameSaved", filename, true));
-						}
+							// Reassign clients to slots
+							//  - Bot ordering is preserved
+							//  - Humans are assigned on a first-come-first-serve basis
+							//  - Leftover humans become spectators
 
-						break;
-					}
-
-					case "LoadGameSave":
-					{
-						if (Type == ServerType.Dedicated || State >= ServerState.GameStarted)
-							break;
-
-						// Sanitize potentially malicious input
-						var filename = o.TargetString;
-						var invalidIndex = -1;
-						var invalidChars = Path.GetInvalidFileNameChars();
-						while ((invalidIndex = filename.IndexOfAny(invalidChars)) != -1)
-							filename = filename.Remove(invalidIndex, 1);
-
-						var savePath = Path.Combine(
-							Platform.SupportDir,
-							"Saves",
-							ModData.Manifest.Id,
-							ModData.Manifest.Metadata.Version,
-							filename);
-
-						GameSave = new GameSave(savePath);
-						LobbyInfo.GlobalSettings = GameSave.GlobalSettings;
-						LobbyInfo.Slots = GameSave.Slots;
-
-						// Reassign clients to slots
-						//  - Bot ordering is preserved
-						//  - Humans are assigned on a first-come-first-serve basis
-						//  - Leftover humans become spectators
-
-						// Start by removing all bots and assigning all players as spectators
-						foreach (var c in LobbyInfo.Clients)
-						{
-							if (c.Bot != null)
-								LobbyInfo.Clients.Remove(c);
-							else
-								c.Slot = null;
-						}
-
-						// Rebuild/remap the saved client state
-						// TODO: Multiplayer saves should leave all humans as spectators so they can manually pick slots
-						var adminClientIndex = LobbyInfo.Clients.First(c => c.IsAdmin).Index;
-						foreach (var kv in GameSave.SlotClients)
-						{
-							if (kv.Value.Bot != null)
+							// Start by removing all bots and assigning all players as spectators
+							foreach (var c in LobbyInfo.Clients)
 							{
-								var bot = new Session.Client()
+								if (c.Bot != null)
+									LobbyInfo.Clients.Remove(c);
+								else
+									c.Slot = null;
+							}
+
+							// Rebuild/remap the saved client state
+							// TODO: Multiplayer saves should leave all humans as spectators so they can manually pick slots
+							var adminClientIndex = LobbyInfo.Clients.First(c => c.IsAdmin).Index;
+							foreach (var kv in GameSave.SlotClients)
+							{
+								if (kv.Value.Bot != null)
 								{
-									Index = ChooseFreePlayerIndex(),
-									State = Session.ClientState.NotReady,
-									BotControllerClientIndex = adminClientIndex
-								};
+									var bot = new Session.Client()
+									{
+										Index = ChooseFreePlayerIndex(),
+										State = Session.ClientState.NotReady,
+										BotControllerClientIndex = adminClientIndex
+									};
 
-								kv.Value.ApplyTo(bot);
-								LobbyInfo.Clients.Add(bot);
-							}
-							else
-							{
-								// This will throw if the server doesn't have enough human clients to fill all player slots
-								// See TODO above - this isn't a problem in practice because MP saves won't use this
-								var client = LobbyInfo.Clients.First(c => c.Slot == null);
-								kv.Value.ApplyTo(client);
+									kv.Value.ApplyTo(bot);
+									LobbyInfo.Clients.Add(bot);
+								}
+								else
+								{
+									// This will throw if the server doesn't have enough human clients to fill all player slots
+									// See TODO above - this isn't a problem in practice because MP saves won't use this
+									var client = LobbyInfo.Clients.First(c => c.Slot == null);
+									kv.Value.ApplyTo(client);
+								}
 							}
+
+							SyncLobbyInfo();
+							SyncLobbyClients();
+
+							break;
 						}
-
-						SyncLobbyInfo();
-						SyncLobbyClients();
-
-						break;
-					}
 				}
 			}
 		}
@@ -1252,7 +1258,7 @@ namespace OpenRA.Server
 			lock (LobbyInfo)
 			{
 				// TODO: Only need to sync the specific client that has changed to avoid conflicts!
-				var clientData = LobbyInfo.Clients.ConvertAll(client => client.Serialize());
+				var clientData = LobbyInfo.Clients.Select(client => client.Serialize()).ToList();
 
 				DispatchServerOrdersToClients(Order.FromTargetString("SyncLobbyClients", clientData.WriteToString(), true));
 
@@ -1352,7 +1358,7 @@ namespace OpenRA.Server
 
 				State = ServerState.GameStarted;
 
-				if (IsMultiplayer)
+				if (Type != ServerType.Local)
 					OrderLatency = gameSpeed.OrderLatency;
 
 				if (GameSave == null && LobbyInfo.GlobalSettings.GameSavesEnabled)
@@ -1366,8 +1372,8 @@ namespace OpenRA.Server
 					{
 						startGameData = new List<MiniYamlNode>()
 						{
-							new("SaveLastOrdersFrame", GameSave.LastOrdersFrame.ToStringInvariant()),
-							new("SaveSyncFrame", GameSave.LastSyncFrame.ToStringInvariant())
+							new MiniYamlNode("SaveLastOrdersFrame", GameSave.LastOrdersFrame.ToString()),
+							new MiniYamlNode("SaveSyncFrame", GameSave.LastSyncFrame.ToString())
 						}.WriteToString();
 					}
 				}
@@ -1412,15 +1418,6 @@ namespace OpenRA.Server
 			}
 		}
 
-		public bool InterpretCommand(string command, Connection conn)
-		{
-			foreach (var t in serverTraits.WithInterface<IInterpretCommand>())
-				if (t.InterpretCommand(this, conn, GetClient(conn), command))
-					return true;
-
-			return false;
-		}
-
 		public ConnectionTarget GetEndpointForLocalConnection()
 		{
 			var endpoints = new List<DnsEndPoint>();
@@ -1438,27 +1435,6 @@ namespace OpenRA.Server
 			return new ConnectionTarget(endpoints);
 		}
 
-		public bool MapIsUnknown(string uid)
-		{
-			if (string.IsNullOrEmpty(uid))
-				return true;
-
-			var status = ModData.MapCache[uid].Status;
-			return status != MapStatus.Available && status != MapStatus.DownloadAvailable;
-		}
-
-		public bool MapIsKnown(string uid)
-		{
-			if (string.IsNullOrEmpty(uid))
-				return false;
-
-			if (MapPool != null && !MapPool.Contains(uid))
-				return false;
-
-			var status = ModData.MapCache[uid].Status;
-			return status == MapStatus.Available || status == MapStatus.DownloadAvailable;
-		}
-
 		interface IServerEvent { void Invoke(Server server); }
 
 		sealed class ConnectionConnectEvent : IServerEvent
@@ -1514,9 +1490,9 @@ namespace OpenRA.Server
 			readonly int[] pingHistory;
 
 			// TODO: future net code changes
-#pragma warning disable IDE0052
+			#pragma warning disable IDE0052
 			readonly byte queueLength;
-#pragma warning restore IDE0052
+			#pragma warning restore IDE0052
 
 			public ConnectionPingEvent(Connection connection, int[] pingHistory, byte queueLength)
 			{