diff --git a/src/Pathfinder.cs b/src/Pathfinder.cs
index bd0d14a..a2e48d3 100644
--- a/src/Pathfinder.cs
+++ b/src/Pathfinder.cs
@@ -8,45 +8,45 @@ namespace WorldOfPeacecraft
 		[StructLayout(LayoutKind.Sequential)]
 		private struct PathNode
 		{
-			[MarshalAs(UnmanagedType.U4)]
-			public uint X;
-			[MarshalAs(UnmanagedType.U4)]
-			public uint Y;
+			[MarshalAs(UnmanagedType.I4)]
+			public int X;
+			[MarshalAs(UnmanagedType.I4)]
+			public int Y;
 		}
 
 		public static unsafe LinkedList<Coordinate> FindPath (Coordinate posFrom, Coordinate posTo, Map map)
 		{
 			PathNode nFrom;
-			nFrom.X = (uint) posFrom.X;
-			nFrom.Y = (uint) posFrom.Y;
+			nFrom.X = posFrom.X;
+			nFrom.Y = posFrom.Y;
 			PathNode nTo;
-			nTo.X = (uint) posTo.X;
-			nTo.Y = (uint) posTo.Y;
+			nTo.X = posTo.X;
+			nTo.Y = posTo.Y;
 			Tile[,] tiles = map.GetTiles();
-			uint mapWidth = (uint) tiles.GetLength (0);
-			uint mapHeight = (uint) tiles.GetLength (1);
-			bool* boolMap = stackalloc bool[(int)(mapWidth * mapHeight)];
+			int mapWidth = tiles.GetLength (0);
+			int mapHeight = tiles.GetLength (1);
+			bool* boolMap = stackalloc bool[mapWidth * mapHeight];
 			for (int y = 0; y < mapHeight; y++) {
 				for (int x = 0; x < mapWidth; x++) {
 					boolMap [x + y * mapWidth] = tiles [x, y].IsWalkable ();
 				}
 			}
-			PathNode* result = stackalloc PathNode[(int) (mapHeight * mapWidth)];
-			uint noSteps = findPath (nFrom, nTo, mapWidth, mapHeight, boolMap, result);
+			PathNode* result = stackalloc PathNode[mapHeight * mapWidth];
+			int noSteps = findPath (nFrom, nTo, mapWidth, mapHeight, boolMap, result);
 			LinkedList<Coordinate> mappedResult = new LinkedList<Coordinate>();
 			for (int i = 0; i < noSteps; i++) {
-				mappedResult.AddLast(new Coordinate((int) result[i].X, (int) result[i].Y));
+				mappedResult.AddLast(new Coordinate(result[i].X, result[i].Y));
 			}
 			return mappedResult;
 		}
 
 		[DllImport("pathfinding")]
-		[return: MarshalAs(UnmanagedType.U4)]
-		private static extern unsafe uint findPath(
+		[return: MarshalAs(UnmanagedType.I4)]
+		private static extern unsafe int findPath(
 			                               PathNode posFrom,
 			                               PathNode posTo,
-			[MarshalAs(UnmanagedType.U4)]  uint mapWidth,
-			[MarshalAs(UnmanagedType.U4)]  uint mapHeight,
+			[MarshalAs(UnmanagedType.I4)]  int mapWidth,
+			[MarshalAs(UnmanagedType.I4)]  int mapHeight,
 			                               bool* map,
 			                               PathNode* result);
 	}