tron@3154: /* $Id$ */
tron@3154: 
tron@3154: #include "stdafx.h"
tron@3154: #include "openttd.h"
tron@3154: #include "tile.h"
tron@3154: #include "tunnel_map.h"
tron@3154: 
tron@3154: TileIndex GetOtherTunnelEnd(TileIndex tile)
tron@3154: {
tron@3154: 	DiagDirection dir = GetTunnelDirection(tile);
Darkvater@4559: 	TileIndexDiff delta = TileOffsByDiagDir(dir);
tron@3154: 	uint z = GetTileZ(tile);
tron@3154: 
tron@3154: 	dir = ReverseDiagDir(dir);
tron@3154: 	do {
tron@3154: 		tile += delta;
tron@3154: 	} while (
tron@3184: 		!IsTunnelTile(tile) ||
tron@3154: 		GetTunnelDirection(tile) != dir ||
tron@3154: 		GetTileZ(tile) != z
tron@3154: 	);
tron@3154: 
tron@3154: 	return tile;
tron@3154: }
tron@3156: 
tron@3156: 
tron@3156: static bool IsTunnelInWayDir(TileIndex tile, uint z, DiagDirection dir)
tron@3156: {
Darkvater@4559: 	TileIndexDiff delta = TileOffsByDiagDir(dir);
tron@3156: 	uint height;
tron@3156: 
tron@3156: 	do {
tron@3156: 		tile -= delta;
tron@3156: 		height = GetTileZ(tile);
tron@3156: 	} while (z < height);
tron@3156: 
tron@3156: 	return
tron@3156: 		z == height &&
tron@3184: 		IsTunnelTile(tile) &&
tron@3156: 		GetTunnelDirection(tile) == dir;
tron@3156: }
tron@3156: 
tron@3156: bool IsTunnelInWay(TileIndex tile, uint z)
tron@3156: {
tron@3156: 	return
tron@3156: 		IsTunnelInWayDir(tile, z, DIAGDIR_NE) ||
tron@3156: 		IsTunnelInWayDir(tile, z, DIAGDIR_SE) ||
tron@3156: 		IsTunnelInWayDir(tile, z, DIAGDIR_SW) ||
tron@3156: 		IsTunnelInWayDir(tile, z, DIAGDIR_NW);
tron@3156: }