Sanitize ProductionQueue and fix bugs in TechTreeCache.

Gives perf win on every tick, and fixes bugs where you lose prereqs when buildings are low power.

OpenRA.Game/Traits/Player/PlayerProductionQueue.cs

@@ -0,0 +1,77 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2010 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. For more information,
+ * see LICENSE.
+ */
+#endregion
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using OpenRA.FileFormats;
+
+namespace OpenRA.Traits
+{
+	public class PlayerProductionQueueInfo : ProductionQueueInfo, ITraitPrerequisite<TechTreeCacheInfo>
+	{
+		public override object Create(ActorInitializer init) { return new PlayerProductionQueue(init.self, this); }
+	}
+
+	public class PlayerProductionQueue : ProductionQueue
+	{
+		public PlayerProductionQueue( Actor self, PlayerProductionQueueInfo info )
+			: base(self, self, info as ProductionQueueInfo) {}
+				
+		[Sync] bool QueueActive = true;
+		public override void Tick( Actor self )
+		{
+			if (self == self.Owner.PlayerActor)
+				QueueActive = self.World.Queries.OwnedBy[self.Owner].WithTrait<Production>()
+					.Where(x => x.Trait.Info.Produces.Contains(Info.Type))
+					.Any();
+			
+			base.Tick(self);
+		}
+		
+		ActorInfo[] None = new ActorInfo[]{};
+		public override IEnumerable<ActorInfo> AllItems()
+		{
+			return QueueActive ? base.AllItems() : None;
+		}
+
+		public override IEnumerable<ActorInfo> BuildableItems()
+		{
+			return QueueActive ? base.BuildableItems() : None;
+		}
+		
+		protected override void BuildUnit( string name )
+		{			
+			// original ra behavior; queue lives on PlayerActor, need to find a production structure
+			var producers = self.World.Queries.OwnedBy[self.Owner]
+			.WithTrait<Production>()
+			.Where(x => x.Trait.Info.Produces.Contains(Info.Type))
+			.OrderByDescending(x => x.Actor.IsPrimaryBuilding() ? 1 : 0 ) // prioritize the primary.
+			.ToArray();
+
+			if (producers.Length == 0)
+			{
+				CancelProduction(name);
+				return;
+			}
+			
+			foreach (var p in producers)
+			{
+				if (IsDisabledBuilding(p.Actor)) continue;
+
+				if (p.Trait.Produce(p.Actor, Rules.Info[ name ]))
+				{
+					FinishProduction();
+					break;
+				}
+			}
+		}
+	}
+}