Added LineBuildNode trait to filter which structure(s) a LineBuild actor can be attached to.

OpenRA.Mods.RA/Buildings/LineBuild.cs

@@ -1,6 +1,6 @@
 #region Copyright & License Information
 /*
- * Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
+ * Copyright 2007-2014 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,
@@ -18,6 +18,9 @@ namespace OpenRA.Mods.RA.Buildings
 	{
 		[Desc("The maximum allowed length of the line.")]
 		public readonly int Range = 5;
+
+		[Desc("LineBuildNode 'Types' to attach to.")]
+		public readonly string[] NodeTypes = { "wall" };
 	}
 
 	public class LineBuild {}

OpenRA.Mods.RA/Buildings/LineBuildNode.cs

@@ -0,0 +1,24 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2014 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 COPYING.
+ */
+#endregion
+
+using OpenRA.FileFormats;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.RA.Buildings
+{
+	[Desc("LineBuild actors attach to LineBuildNodes.")]
+	public class LineBuildNodeInfo : TraitInfo<LineBuildNode>
+	{
+		[Desc("This actor is of LineBuild 'NodeType'...")]
+		public readonly string[] Types = { "wall" };
+	}
+
+	public class LineBuildNode {}
+}

OpenRA.Mods.RA/Buildings/Util.cs

@@ -42,7 +42,7 @@ namespace OpenRA.Mods.RA.Buildings
 
 		public static IEnumerable<CPos> GetLineBuildCells(World world, CPos location, string name, BuildingInfo bi)
 		{
-			int range = Rules.Info[name].Traits.Get<LineBuildInfo>().Range;
+			var lbi = Rules.Info[name].Traits.Get<LineBuildInfo>();
 			var topLeft = location;	// 1x1 assumption!
 
 			if (world.IsCellBuildable(topLeft, bi))
@@ -54,17 +54,21 @@ namespace OpenRA.Mods.RA.Buildings
 			int[] dirs = { 0, 0, 0, 0 };
 			for (int d = 0; d < 4; d++)
 			{
-				for (int i = 1; i < range; i++)
+				for (int i = 1; i < lbi.Range; i++)
 				{
 					if (dirs[d] != 0)
 						continue;
 
-					CPos cell = topLeft + i * vecs[d];
+					var cell = topLeft + i * vecs[d];
 					if (world.IsCellBuildable(cell, bi))
 						continue; // Cell is empty; continue search
 
 					// Cell contains an actor. Is it the type we want?
-					if (world.ActorsWithTrait<LineBuild>().Any(a => (a.Actor.Info.Name == name && a.Actor.Location.X == cell.X && a.Actor.Location.Y == cell.Y)))
+					if (world.ActorsWithTrait<LineBuildNode>().Any(a =>
+					(
+						a.Actor.Location == cell &&
+						a.Actor.Info.Traits.Get<LineBuildNodeInfo>().Types.Intersect(lbi.NodeTypes).Any()
+					)))
 						dirs[d] = i; // Cell contains actor of correct type
 					else
 						dirs[d] = -1; // Cell is blocked by another actor type

OpenRA.Mods.RA/OpenRA.Mods.RA.csproj

@@ -490,6 +490,7 @@
     <Compile Include="Orders\BeaconOrderGenerator.cs" />
     <Compile Include="Widgets\LogicKeyListenerWidget.cs" />
     <Compile Include="Widgets\Logic\ControlGroupLogic.cs" />
+    <Compile Include="Buildings\LineBuildNode.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\OpenRA.FileFormats\OpenRA.FileFormats.csproj">