Introducing per-player shrouds.

- Each player has their own shroud and their visibility does not extend outside of the shroud. 
- Units and buildings can no longer target other units outside of their visibility. Buildings can still be targetted if they have been explored.
- GPS will provide visibility in the fog-of-war.
- Spies that infiltrate radar domes will gain their victim's exploration and reset it on all clients (if the victim does not have GPS)

OpenRA.Mods.RA/SupportPowers/GpsPower.cs

@@ -58,15 +58,12 @@ namespace OpenRA.Mods.RA
 		public void RefreshGps(Actor atek)
 		{
 			RefreshGranted();
-
+			
 			foreach (TraitPair<GpsWatcher> i in atek.World.ActorsWithTrait<GpsWatcher>())
 				i.Trait.RefreshGranted();
 
-			if (atek.World.LocalPlayer == null)
-				return;
-
-			if ((Granted || GrantedAllies) && (atek.World.LocalPlayer.Stances[atek.Owner] == Stance.Ally))
-				atek.World.WorldActor.Trait<Shroud>().ExploreAll(atek.World);
+			if ((Granted || GrantedAllies) && atek.World.LocalPlayer != null && (atek.World.LocalPlayer.Stances[atek.Owner] == Stance.Ally))
+				atek.Owner.Shroud.ExploreAll(atek.World);
 		}
 
 		void RefreshGranted()
@@ -74,6 +71,9 @@ namespace OpenRA.Mods.RA
 			Granted = (actors.Count > 0 && Launched);
 			GrantedAllies = owner.World.ActorsWithTrait<GpsWatcher>().Any(p =>
 					p.Actor.Owner.Stances[owner] == Stance.Ally && p.Trait.Granted);
+					
+			if (Granted || GrantedAllies)
+				owner.Shroud.ExploreAll(owner.World);
 		}
 	}