diff --git a/map.h b/map.h
--- a/map.h
+++ b/map.h
@@ -2,7 +2,7 @@
 #define MAP_H
 
 #define TILE_FROM_XY(x,y) (int)((((y) >> 4) << MapLogX()) + ((x) >> 4))
-#define TILE_XY(x,y) (int)(((y) << MapLogX()) + (x))
+#define TILE_XY(x,y) (((y) << MapLogX()) + (x))
 
 #define TILE_MASK(x) ((x) & ((1 << (MapLogX() + MapLogY())) - 1))
 
@@ -26,8 +26,8 @@ static inline uint MapMaxY(void) { retur
 /* The number of tiles in the map */
 static inline uint MapSize(void) { return MapSizeX() * MapSizeY(); }
 
+typedef uint32 TileIndex;
 
-typedef uint16 TileIndex;
 
 static inline uint TileX(TileIndex tile)
 {
@@ -40,7 +40,7 @@ static inline uint TileY(TileIndex tile)
 }
 
 
-typedef int16 TileIndexDiff;
+typedef int32 TileIndexDiff;
 
 typedef struct TileIndexDiffC {
 	int16 x;