(svn r3658) Add functions and symbolic names to retrieve road tile types and road pieces

road.h

@@ -0,0 +1,34 @@
+/* $Id$ */
+
+#ifndef ROAD_H
+#define ROAD_H
+
+#include "macros.h"
+
+typedef enum RoadBits {
+	ROAD_NW  = 1,
+	ROAD_SW  = 2,
+	ROAD_SE  = 4,
+	ROAD_NE  = 8,
+	ROAD_X   = ROAD_SW | ROAD_NE,
+	ROAD_Y   = ROAD_NW | ROAD_SE,
+	ROAD_ALL = ROAD_X  | ROAD_Y
+} RoadBits;
+
+static inline RoadBits GetRoadBits(TileIndex tile)
+{
+	return GB(_m[tile].m5, 0, 4);
+}
+
+typedef enum RoadType {
+	ROAD_NORMAL,
+	ROAD_CROSSING,
+	ROAD_DEPOT
+} RoadType;
+
+static inline RoadType GetRoadType(TileIndex tile)
+{
+	return GB(_m[tile].m5, 4, 4);
+}
+
+#endif