From 561cb6cfe0f3b6110038bca756cc959a7564d545 Mon Sep 17 00:00:00 2001
From: Paul Chote <paul@chote.net>
Date: Sat, 6 Jul 2013 17:29:24 +1200
Subject: [PATCH] Rewrite Leap activity to be more robust.

The dog will now always leap to the target
subcell (even if the target dies or moves),
and will kill whatever happens to be in the
target cell when it lands.
---
 OpenRA.Mods.RA/Activities/Leap.cs   | 47 +++++++++++++++++------------
 OpenRA.Mods.RA/Attack/AttackLeap.cs |  2 --
 OpenRA.Mods.RA/Move/Mobile.cs       |  4 ++-
 3 files changed, 31 insertions(+), 22 deletions(-)

diff --git a/OpenRA.Mods.RA/Activities/Leap.cs b/OpenRA.Mods.RA/Activities/Leap.cs
index d8f4537386..64898fa68b 100644
--- a/OpenRA.Mods.RA/Activities/Leap.cs
+++ b/OpenRA.Mods.RA/Activities/Leap.cs
@@ -8,6 +8,7 @@
  */
 #endregion
 
+using System;
 using System.Linq;
 using OpenRA.Mods.RA.Move;
 using OpenRA.Mods.RA.Render;
@@ -17,16 +18,29 @@ namespace OpenRA.Mods.RA.Activities
 {
 	class Leap : Activity
 	{
-		Target target;
-		PPos initialLocation;
+		Mobile mobile;
+
+		PPos from;
+		PPos to;
 
 		int moveFraction;
-		const int delay = 6;
+		const int length = 6;
 
 		public Leap(Actor self, Target target)
 		{
-			this.target = target;
-			initialLocation = (PPos) self.Trait<Mobile>().PxPosition;
+			if (!target.IsActor)
+				throw new InvalidOperationException("Leap requires a target actor");
+
+			var targetMobile = target.Actor.TraitOrDefault<Mobile>();
+			if (targetMobile == null)
+				throw new InvalidOperationException("Leap requires a target actor with the Mobile trait");
+
+			mobile = self.Trait<Mobile>();
+			mobile.SetLocation(mobile.fromCell, mobile.fromSubCell, targetMobile.fromCell, targetMobile.fromSubCell);
+			mobile.IsMoving = true;
+
+			from = self.CenterLocation;
+			to = Util.CenterOfCell(targetMobile.fromCell) + MobileInfo.SubCellOffsets[targetMobile.fromSubCell];
 
 			self.Trait<RenderInfantry>().Attacking(self, target);
 			Sound.Play("dogg5p.aud", self.CenterLocation);
@@ -34,23 +48,18 @@ namespace OpenRA.Mods.RA.Activities
 
 		public override Activity Tick(Actor self)
 		{
-			if( moveFraction == 0 && IsCanceled ) return NextActivity;
-			if (!target.IsValid) return NextActivity;
+			if (moveFraction == 0 && IsCanceled)
+				return NextActivity;
 
-			self.Trait<AttackLeap>().IsLeaping = true;
-			var mobile = self.Trait<Mobile>();
-			++moveFraction;
-
-			mobile.PxPosition = PPos.Lerp(initialLocation, target.PxPosition, moveFraction, delay);
-
-			if (moveFraction >= delay)
+			mobile.AdjustPxPosition(self, PPos.Lerp(from, to, moveFraction++, length - 1));
+			if (moveFraction >= length)
 			{
-				self.TraitsImplementing<IMove>().FirstOrDefault()
-					.SetPosition(self, target.CenterLocation.ToCPos());
+				mobile.SetLocation(mobile.toCell, mobile.toSubCell, mobile.toCell, mobile.toSubCell);
+				mobile.FinishedMoving(self);
+				mobile.IsMoving = false;
 
-				if (target.IsActor)
-					target.Actor.Kill(self);
-				self.Trait<AttackLeap>().IsLeaping = false;
+				// Kill whatever else is in our new cell
+				self.World.ActorMap.GetUnitsAt(mobile.toCell, mobile.toSubCell).Except(new []{self}).Do(a => a.Kill(self));
 				return NextActivity;
 			}
 
diff --git a/OpenRA.Mods.RA/Attack/AttackLeap.cs b/OpenRA.Mods.RA/Attack/AttackLeap.cs
index 613d1da196..0dbf477093 100644
--- a/OpenRA.Mods.RA/Attack/AttackLeap.cs
+++ b/OpenRA.Mods.RA/Attack/AttackLeap.cs
@@ -22,8 +22,6 @@ namespace OpenRA.Mods.RA
 
 	class AttackLeap : AttackFrontal, ISync
 	{
-		[Sync] internal bool IsLeaping;
-
 		public AttackLeap(Actor self, AttackLeapInfo info)
 			: base(self, info) {}
 
diff --git a/OpenRA.Mods.RA/Move/Mobile.cs b/OpenRA.Mods.RA/Move/Mobile.cs
index ad75f3f9cf..2fd6c1b279 100755
--- a/OpenRA.Mods.RA/Move/Mobile.cs
+++ b/OpenRA.Mods.RA/Move/Mobile.cs
@@ -170,7 +170,9 @@ namespace OpenRA.Mods.RA.Move
 
 		public void SetLocation(CPos from, SubCell fromSub, CPos to, SubCell toSub)
 		{
-			if (fromCell == from && toCell == to) return;
+			if (fromCell == from && toCell == to && fromSubCell == fromSub && toSubCell == toSub)
+				return;
+
 			RemoveInfluence();
 			__fromCell = from;
 			__toCell = to;