diff --git a/src/ground_vehicle.hpp b/src/ground_vehicle.hpp
index 0a17ea209c..0e22b144bf 100644
--- a/src/ground_vehicle.hpp
+++ b/src/ground_vehicle.hpp
@@ -125,7 +125,6 @@ struct GroundVehicle : public SpecializedVehicle<T, Type> {
 				 * direction it is sloped, we get the 'z' at the center of
 				 * the tile (middle_z) and the edge of the tile (old_z),
 				 * which we then can compare. */
-				static const int HALF_TILE_SIZE = TILE_SIZE / 2;
 				static const int INV_TILE_SIZE_MASK = ~(TILE_SIZE - 1);
 
 				byte middle_z = GetSlopeZ((this->x_pos & INV_TILE_SIZE_MASK) | HALF_TILE_SIZE, (this->y_pos & INV_TILE_SIZE_MASK) | HALF_TILE_SIZE);
diff --git a/src/tile_type.h b/src/tile_type.h
index a939e030ac..b43b0e6b5b 100644
--- a/src/tile_type.h
+++ b/src/tile_type.h
@@ -13,7 +13,8 @@
 #define TILE_TYPE_H
 
 static const uint TILE_SIZE      = 16;            ///< Tiles are 16x16 "units" in size
-static const uint TILE_UNIT_MASK = TILE_SIZE - 1; ///< for masking in/out the inner-tile units.
+static const uint HALF_TILE_SIZE = TILE_SIZE / 2; ///< Half of tile size, to get centre of a tile.
+static const uint TILE_UNIT_MASK = TILE_SIZE - 1; ///< For masking in/out the inner-tile units.
 static const uint TILE_PIXELS    = 32;            ///< a tile is 32x32 pixels
 static const uint TILE_HEIGHT    =  8;            ///< The standard height-difference between tiles on two levels is 8 (z-diff 8)