Overhaul target line rendering:

- Targets are now defined by the activities
- Queued activities are shown
- Support custom attack colors

OpenRA.Mods.Common/Activities/Enter.cs

@@ -9,6 +9,7 @@
  */
 #endregion
 
+using System.Collections.Generic;
 using OpenRA.Activities;
 using OpenRA.Mods.Common.Traits;
 using OpenRA.Primitives;
@@ -75,10 +76,6 @@ namespace OpenRA.Mods.Common.Activities
 
 			TickInner(self, target, useLastVisibleTarget);
 
-			// Update target lines if required
-			if (useLastVisibleTarget != oldUseLastVisibleTarget && targetLineColor.HasValue)
-				self.SetTargetLine(useLastVisibleTarget ? lastVisibleTarget : target, targetLineColor.Value, false);
-
 			// We need to wait for movement to finish before transitioning to
 			// the next state or next activity
 			if (!TickChild(self))
@@ -146,5 +143,11 @@ namespace OpenRA.Mods.Common.Activities
 
 			return false;
 		}
+
+		public override IEnumerable<TargetLineNode> TargetLineNodes(Actor self)
+		{
+			if (targetLineColor != null)
+				yield return new TargetLineNode(useLastVisibleTarget ? lastVisibleTarget : target, targetLineColor.Value);
+		}
 	}
 }