Make the non-support of frozen actor targeting in EnterOrderTargeter explicit.

OpenRA.Mods.RA/Orders/EnterAlliedActorTargeter.cs

@@ -0,0 +1,45 @@
+#region Copyright & License Information
+/*
+ * Copyright 2007-2011 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 System;
+using System.Collections.Generic;
+using OpenRA.Traits;
+
+namespace OpenRA.Mods.RA.Orders
+{
+	public class EnterAlliedActorTargeter<T> : UnitOrderTargeter
+	{
+		readonly Func<Actor, bool> canTarget;
+		readonly Func<Actor, bool> useEnterCursor;
+
+		public EnterAlliedActorTargeter(string order, int priority,
+			Func<Actor, bool> canTarget, Func<Actor, bool> useEnterCursor)
+			: base (order, priority, "enter", false, true)
+		{
+			this.canTarget = canTarget;
+			this.useEnterCursor = useEnterCursor;
+		}
+
+		public override bool CanTargetActor(Actor self, Actor target, TargetModifiers modifiers, ref string cursor)
+		{
+			if (!target.HasTrait<T>() || !canTarget(target))
+				return false;
+
+			cursor = useEnterCursor(target) ? "enter" : "enter-blocked";
+			return true;
+		}
+
+		public override bool CanTargetFrozenActor(Actor self, FrozenActor target, TargetModifiers modifiers, ref string cursor)
+		{
+			// Allied actors are never frozen
+			return false;
+		}
+	}
+}