make repath much less aggressive while attacking, to fix perf

OpenRA.Mods.RA/Activities/Attack.cs

@@ -23,6 +23,11 @@ namespace OpenRA.Mods.RA.Activities
 		int Range;
 		bool AllowMovement;
 
+        int nextPathTime;
+
+        const int delayBetweenPathingAttempts = 20;
+        const int delaySpread = 5;
+
 		public Attack(Target target, int range, bool allowMovement)
 		{
 			Target = target;
@@ -33,10 +38,7 @@ namespace OpenRA.Mods.RA.Activities
 			AllowMovement = allowMovement;
 		}
 
-		public Attack(Target target, int range) : this(target, range, true)
+		public Attack(Target target, int range) : this(target, range, true) {}
-		{
-			
-		}
 
 		public override IActivity Tick( Actor self )
 		{
@@ -58,7 +60,15 @@ namespace OpenRA.Mods.RA.Activities
 				return NextActivity;
 
             if (!Combat.IsInRange(self.CenterLocation, Range, Target))
+            {
+                if (--nextPathTime > 0)
+                    return this;
+
+                nextPathTime = self.World.SharedRandom.Next(delayBetweenPathingAttempts - delaySpread,
+                    delayBetweenPathingAttempts + delaySpread);
+
                 return (AllowMovement) ? Util.SequenceActivities(self.Trait<Mobile>().MoveWithinRange(Target, Range), this) : NextActivity;
+            }
 
 			var desiredFacing = Util.GetFacing(Target.CenterLocation - self.CenterLocation, 0);
 			if (facing.Facing != desiredFacing)

OpenRA.Mods.RA/Activities/Follow.cs

@@ -18,6 +18,10 @@ namespace OpenRA.Mods.RA.Activities
 	{
 		Target Target;
 		int Range;
+        int nextPathTime;
+
+        const int delayBetweenPathingAttempts = 20;
+        const int delaySpread = 5;
 
 		public Follow(Target target, int range)
 		{
@@ -33,6 +37,10 @@ namespace OpenRA.Mods.RA.Activities
 			var inRange = ( Util.CellContaining( Target.CenterLocation ) - self.Location ).LengthSquared < Range * Range;
 
 			if( inRange ) return this;
+            if (--nextPathTime > 0) return this;
+
+            nextPathTime = self.World.SharedRandom.Next(delayBetweenPathingAttempts - delaySpread,
+                delayBetweenPathingAttempts + delaySpread);
 
             var mobile = self.Trait<Mobile>();
 			return Util.SequenceActivities( mobile.MoveWithinRange( Target, Range ), this );