Add GrantConditionOnLineBuildDirection trait.

OpenRA.Mods.Common/OpenRA.Mods.Common.csproj

@@ -800,6 +800,7 @@
     <Compile Include="Traits\Render\WithChargeAnimation.cs" />
     <Compile Include="Traits\Render\WithChargeOverlay.cs" />
     <Compile Include="WebServices.cs" />
+    <Compile Include="Traits\Conditions\GrantConditionOnLineBuildDirection.cs" />
     <Compile Include="Traits\Conditions\LineBuildSegmentExternalCondition.cs" />
   </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />

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

@@ -15,6 +15,15 @@ using OpenRA.Traits;
 
 namespace OpenRA.Mods.Common.Traits
 {
+	public enum LineBuildDirection { Unset, X, Y }
+	public class LineBuildDirectionInit : IActorInit<LineBuildDirection>
+	{
+		[FieldFromYamlKey] readonly LineBuildDirection value = LineBuildDirection.Unset;
+		public LineBuildDirectionInit() { }
+		public LineBuildDirectionInit(LineBuildDirection init) { value = init; }
+		public LineBuildDirection Value(World world) { return value; }
+	}
+
 	public class LineBuildParentInit : IActorInit<Actor[]>
 	{
 		[FieldFromYamlKey] public readonly string[] ParentNames = new string[0];

OpenRA.Mods.Common/Traits/Conditions/GrantConditionOnLineBuildDirection.cs

@@ -0,0 +1,51 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2017 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 OpenRA.Traits;
+
+namespace OpenRA.Mods.Common.Traits
+{
+	public class GrantConditionOnLineBuildDirectionInfo : ITraitInfo, Requires<LineBuildInfo>
+	{
+		[FieldLoader.Require]
+		[GrantedConditionReference]
+		[Desc("Condition to grant.")]
+		public readonly string Condition = null;
+
+		[FieldLoader.Require]
+		[Desc("Line build direction to trigger the condition.")]
+		public readonly LineBuildDirection Direction = LineBuildDirection.X;
+
+		public object Create(ActorInitializer init) { return new GrantConditionOnLineBuildDirection(init, this); }
+	}
+
+	public class GrantConditionOnLineBuildDirection : INotifyCreated
+	{
+		readonly GrantConditionOnLineBuildDirectionInfo info;
+		readonly LineBuildDirection direction;
+
+		public GrantConditionOnLineBuildDirection(ActorInitializer init, GrantConditionOnLineBuildDirectionInfo info)
+		{
+			this.info = info;
+			direction = init.Get<LineBuildDirectionInit>().Value(init.World);
+		}
+
+		void INotifyCreated.Created(Actor self)
+		{
+			if (direction != info.Direction)
+				return;
+
+			var conditionManager = self.TraitOrDefault<ConditionManager>();
+			if (conditionManager != null && !string.IsNullOrEmpty(info.Condition))
+				conditionManager.GrantCondition(self, info.Condition);
+		}
+	}
+}

OpenRA.Mods.Common/Traits/Player/PlaceBuilding.cs

@@ -103,6 +103,7 @@ namespace OpenRA.Mods.Common.Traits
 							new LocationInit(t.First),
 							new OwnerInit(order.Player),
 							new FactionInit(faction),
+							new LineBuildDirectionInit(t.First.X == order.TargetLocation.X ? LineBuildDirection.Y : LineBuildDirection.X),
 							new LineBuildParentInit(new[] { t.Second, placed })
 						});
 					}