fix ore/tib growth -- we can always grow in a cell that already conta…

…ins our resource type. buildable/terraintype checks only come into it when growing into *new* cells

OpenRA.Mods.RA/SeedsResource.cs

@@ -49,9 +49,9 @@ public void Tick(Actor self)
 					.Cast<int2?>().FirstOrDefault();
 
 				// Todo: Valid terrain should be specified in the resource
-				if (cell != null &&
-					(resLayer.GetResource(cell.Value) == resourceType || resLayer.GetResource(cell.Value) == null) &&
-					self.World.IsCellBuildable(cell.Value, false))
+				if (cell != null && self.World.Map.IsInMap(cell.Value) && 
+					(resLayer.GetResource(cell.Value) == resourceType 
+					|| (resLayer.GetResource(cell.Value) == null && self.World.IsCellBuildable(cell.Value, false))))
 					resLayer.AddResource(resourceType, cell.Value.X, cell.Value.Y, 1);
 
 				ticks = info.Interval;