Make Tick return bool

OpenRA.Mods.Common/Activities/Attack.cs

@@ -83,10 +83,10 @@ namespace OpenRA.Mods.Common.Activities
 			return target.Recalculate(self.Owner, out targetIsHiddenActor);
 		}
 
-		public override Activity Tick(Actor self)
+		public override bool Tick(Actor self)
 		{
 			if (IsCanceling)
-				return NextActivity;
+				return true;
 
 			bool targetIsHiddenActor;
 			target = RecalculateTarget(self, out targetIsHiddenActor);
@@ -106,7 +106,7 @@ namespace OpenRA.Mods.Common.Activities
 			// If we are ticking again after previously sequencing a MoveWithRange then that move must have completed
 			// Either we are in range and can see the target, or we've lost track of it and should give up
 			if (wasMovingWithinRange && targetIsHiddenActor)
-				return NextActivity;
+				return true;
 
 			// Update target lines if required
 			if (useLastVisibleTarget != oldUseLastVisibleTarget)
@@ -114,7 +114,7 @@ namespace OpenRA.Mods.Common.Activities
 
 			// Target is hidden or dead, and we don't have a fallback position to move towards
 			if (useLastVisibleTarget && !lastVisibleTarget.IsValidFor(self))
-				return NextActivity;
+				return true;
 
 			wasMovingWithinRange = false;
 			var pos = self.CenterPosition;
@@ -125,12 +125,12 @@ namespace OpenRA.Mods.Common.Activities
 			{
 				// We've reached the assumed position but it is not there or we can't move any further - give up
 				if (checkTarget.IsInRange(pos, lastVisibleMaximumRange) || move == null || lastVisibleMaximumRange == WDist.Zero)
-					return NextActivity;
+					return true;
 
 				// Move towards the last known position
 				wasMovingWithinRange = true;
 				QueueChild(move.MoveWithinRange(target, WDist.Zero, lastVisibleMaximumRange, checkTarget.CenterPosition, Color.Red));
-				return this;
+				return false;
 			}
 
 			attackStatus = AttackStatus.UnableToAttack;
@@ -145,9 +145,9 @@ namespace OpenRA.Mods.Common.Activities
 				wasMovingWithinRange = true;
 
 			if (attackStatus >= AttackStatus.NeedsToTurn)
-				return this;
+				return false;
 
-			return NextActivity;
+			return true;
 		}
 
 		protected virtual AttackStatus TickAttack(Actor self, AttackFrontal attack)