Revert "Remove BuildingInfluence trait."

This reverts commit 34bf14332887267e206d217956aab143720fc87d.

OpenRA.Mods.Common/Traits/Buildings/Building.cs

@@ -263,6 +263,7 @@ namespace OpenRA.Mods.Common.Traits
 		readonly CPos topLeft;
 
 		readonly Actor self;
+		readonly BuildingInfluence influence;
 
 		(CPos, SubCell)[] occupiedCells;
 		(CPos, SubCell)[] targetableCells;
@@ -276,6 +277,7 @@ namespace OpenRA.Mods.Common.Traits
 			self = init.Self;
 			topLeft = init.GetValue<LocationInit, CPos>();
 			Info = info;
+			influence = self.World.WorldActor.Trait<BuildingInfluence>();
 
 			occupiedCells = Info.OccupiedTiles(TopLeft)
 				.Select(c => (c, SubCell.FullCell)).ToArray();
@@ -305,11 +307,13 @@ namespace OpenRA.Mods.Common.Traits
 				RemoveSmudges();
 
 			self.World.AddToMaps(self, this);
+			influence.AddInfluence(self, Info.Tiles(self.Location));
 		}
 
 		void INotifyRemovedFromWorld.RemovedFromWorld(Actor self)
 		{
 			self.World.RemoveFromMaps(self, this);
+			influence.RemoveInfluence(self, Info.Tiles(self.Location));
 		}
 
 		void INotifySold.Selling(Actor self)

OpenRA.Mods.Common/Traits/Buildings/BuildingInfluence.cs

@@ -0,0 +1,54 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
+ * 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.Generic;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Traits
+{
+	[Desc("A dictionary of buildings placed on the map. Attach this to the world actor.")]
+	public class BuildingInfluenceInfo : TraitInfo
+	{
+		public override object Create(ActorInitializer init) { return new BuildingInfluence(init.World); }
+	}
+
+	public class BuildingInfluence
+	{
+		readonly Map map;
+		readonly CellLayer<Actor> influence;
+
+		public BuildingInfluence(World world)
+		{
+			map = world.Map;
+
+			influence = new CellLayer<Actor>(map);
+		}
+
+		internal void AddInfluence(Actor a, IEnumerable<CPos> tiles)
+		{
+			foreach (var u in tiles)
+				if (influence.Contains(u) && influence[u] == null)
+					influence[u] = a;
+		}
+
+		internal void RemoveInfluence(Actor a, IEnumerable<CPos> tiles)
+		{
+			foreach (var u in tiles)
+				if (influence.Contains(u) && influence[u] == a)
+					influence[u] = null;
+		}
+
+		public Actor GetBuildingAt(CPos cell)
+		{
+			return influence.Contains(cell) ? influence[cell] : null;
+		}
+	}
+}

OpenRA.Mods.Common/UpdateRules/Rules/20200503/RemoveBuildingInfluence.cs

@@ -1,34 +0,0 @@
-#region Copyright & License Information
-/*
- * Copyright 2007-2020 The OpenRA Developers (see AUTHORS)
- * 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.Generic;
-
-namespace OpenRA.Mods.Common.UpdateRules.Rules
-{
-	public class RemoveBuildingInfluence : UpdateRule
-	{
-		public override string Name { get { return "BuildingInfluence trait has been removed."; } }
-
-		public override string Description
-		{
-			get
-			{
-				return "BuildingInfluence trait has been removed. Its functionality has been integrated into ActorMap.";
-			}
-		}
-
-		public override IEnumerable<string> UpdateActorNode(ModData modData, MiniYamlNode actorNode)
-		{
-			actorNode.RemoveNodes("BuildingInfluence");
-			yield break;
-		}
-	}
-}

OpenRA.Mods.Common/UpdateRules/UpdatePath.cs

@@ -78,7 +78,6 @@ namespace OpenRA.Mods.Common.UpdateRules
 				new RenameCircleContrast(),
 				new SplitDamagedByTerrain(),
 				new RemoveLaysTerrain(),
-				new RemoveBuildingInfluence(),
 			})
 		};
 

mods/cnc/rules/world.yaml

@@ -159,6 +159,7 @@ World:
 	PlayerCommands:
 	HelpCommand:
 	ScreenShaker:
+	BuildingInfluence:
 	LegacyBridgeLayer:
 		Bridges: bridge1, bridge2, bridge3, bridge4
 	ProductionQueueFromSelection:

mods/d2k/rules/world.yaml

@@ -129,6 +129,7 @@ World:
 	PlayerCommands:
 	HelpCommand:
 	ScreenShaker:
+	BuildingInfluence:
 	ProductionQueueFromSelection:
 		ProductionPaletteWidget: PRODUCTION_PALETTE
 	ActorSpawnManager:

mods/ra/rules/world.yaml

@@ -181,6 +181,7 @@ World:
 	PlayerCommands:
 	HelpCommand:
 	ScreenShaker:
+	BuildingInfluence:
 	ProductionQueueFromSelection:
 		ProductionPaletteWidget: PRODUCTION_PALETTE
 	LegacyBridgeLayer:

mods/ts/rules/world.yaml

@@ -247,6 +247,7 @@ World:
 	DebugVisualizationCommands:
 	PlayerCommands:
 	HelpCommand:
+	BuildingInfluence:
 	ProductionQueueFromSelection:
 		ProductionPaletteWidget: PRODUCTION_PALETTE
 	DomainIndex: