/** Called by YAPF to calculate the cost from the origin to the given node.

	*   Calculates only the cost of given node, adds it to the parent node cost

	*   and stores the result into Node::m_cost member */

	FORCEINLINE bool PfCalcCost(Node& n)

	{

		assert(!n.flags_u.flags_s.m_targed_seen);

		CPerfStart perf_cost(Yapf().m_perf_cost);

		int parent_cost = (n.m_parent != NULL) ? n.m_parent->m_cost : 0;

		int first_tile_cost = 0;

		int segment_cost = 0;

		int extra_cost = 0;

		const Vehicle* v = Yapf().GetVehicle();

		// start at n.m_key.m_tile / n.m_key.m_td and walk to the end of segment

		TileIndex prev_tile      = (n.m_parent != NULL) ? n.m_parent->GetLastTile() : INVALID_TILE;

		Trackdir  prev_trackdir  = (n.m_parent != NULL) ? n.m_parent->GetLastTrackdir() : INVALID_TRACKDIR;

		TileType  prev_tile_type = (n.m_parent != NULL) ? GetTileType(n.m_parent->GetLastTile()) : MP_VOID;

		TileIndex tile = n.m_key.m_tile;

		Trackdir trackdir = n.m_key.m_td;

		TileType tile_type = GetTileType(tile);

		RailType rail_type = GetTileRailType(tile, trackdir);

		while (true) {

			segment_cost += Yapf().OneTileCost(tile, trackdir);

			segment_cost += Yapf().CurveCost(prev_trackdir, trackdir);

			segment_cost += Yapf().SlopeCost(tile, trackdir);

			segment_cost += Yapf().SignalCost(n, tile, trackdir);

			if (n.m_segment->flags_u.flags_s.m_end_of_line) {

				break;

			}

			// finish if we have reached the destination

			if (target_seen) {

				break;

			}

			// finish on first station tile - segment should end here to avoid target skipping

			// when cached segments are used

			if (tile_type == MP_STATION && prev_tile_type != MP_STATION) {

				break;

			}

			// finish also on waypoint - same workaround as for first station tile

			if (tile_type == MP_RAILWAY && IsRailWaypoint(tile)) {

				break;

			}

			// if there are no reachable trackdirs on the next tile, we have end of road

			TrackFollower F(v, &Yapf().m_perf_ts_cost);

			if (!F.Follow(tile, trackdir)) {

				// we can't continue?

				// n.m_segment->flags_u.flags_s.m_end_of_line = true;

				break;

			}

			// if there are more trackdirs available & reachable, we are at the end of segment

				// stop if train is on simple loop with no junctions

				if (F.m_new_tile == n.m_key.m_tile && new_td == n.m_key.m_td)

					return false;

			}

			// if tail type changes, finish segment (cached segment can't contain more rail types)

			{

				RailType new_rail_type = GetTileRailType(F.m_new_tile, (Trackdir)FindFirstBit2x64(F.m_new_td_bits));

				if (new_rail_type != rail_type) {

					break;

				}

				rail_type = new_rail_type;

			}

			// move to the next tile

			prev_tile = tile;

			prev_trackdir = trackdir;

			prev_tile_type = tile_type;

			tile = F.m_new_tile;

			trackdir = new_td;

			tile_type = GetTileType(tile);

			// reversing in depot penalty

			if (tile == prev_tile) {

				segment_cost += Yapf().PfGetSettings().rail_depot_reverse_penalty;

				break;

			}

			// if we skipped some tunnel tiles, add their cost

			segment_cost += YAPF_TILE_LENGTH * F.m_tunnel_tiles_skipped;

			// add min/max speed penalties

			int min_speed = 0;

			int max_speed = F.GetSpeedLimit(&min_speed);

			if (max_speed < v->max_speed)

				segment_cost += YAPF_TILE_LENGTH * (v->max_speed - max_speed) / v->max_speed;

			if (min_speed > v->max_speed)

				segment_cost += YAPF_TILE_LENGTH * (min_speed - v->max_speed);

			// finish if we already exceeded the maximum cost

			if (m_max_cost > 0 && (parent_cost + first_tile_cost + segment_cost) > m_max_cost) {

				return false;

			}

			if (first_tile_cost == 0) {

				// we just have done first tile

		m_compatible_railtypes = v->u.rail.compatible_railtypes;

	}

	bool IsCompatibleRailType(RailType rt)

	{

		return HASBIT(m_compatible_railtypes, rt);

	}

};

template <class Types>

class CYapfDestinationAnyDepotRailT

	: public CYapfDestinationRailBase

{

public:

	typedef typename Types::Tpf Tpf;              ///< the pathfinder class (derived from THIS class)

	typedef typename Types::NodeList::Titem Node; ///< this will be our node type

	typedef typename Node::Key Key;               ///< key to hash tables

	/// to access inherited path finder

	Tpf& Yapf() {return *static_cast<Tpf*>(this);}

	/// Called by YAPF to detect if node ends in the desired destination

	FORCEINLINE bool PfDetectDestination(Node& n)

	{

		return bDest;

	}

	/** Called by YAPF to calculate cost estimate. Calculates distance to the destination

	*   adds it to the actual cost from origin and stores the sum to the Node::m_estimate */

	FORCEINLINE bool PfCalcEstimate(Node& n)

	{

		n.m_estimate = n.m_cost;

		return true;

	}

};

template <class Types>

class CYapfDestinationTileOrStationRailT

	: public CYapfDestinationRailBase

{

public:

	typedef typename Types::Tpf Tpf;              ///< the pathfinder class (derived from THIS class)

	typedef typename Types::NodeList::Titem Node; ///< this will be our node type

	typedef typename Node::Key Key;               ///< key to hash tables

protected:

	TileIndex    m_destTile;

	TrackdirBits m_destTrackdirs;

		uint x = TileX(st->train_tile) + st->trainst_w / 2;

		uint y = TileY(st->train_tile) + st->trainst_h / 2;

		// return the tile of our target coordinates

		return TileXY(x, y);

	}

public:

	void SetDestination(Vehicle* v)

	{

		if (v->current_order.type == OT_GOTO_STATION) {

			m_destTile = CalcStationCenterTile(v->current_order.station);

			m_dest_station_id = v->current_order.station;

			m_destTrackdirs = INVALID_TRACKDIR_BIT;

		} else {

			m_destTile = v->dest_tile;

			m_dest_station_id = INVALID_STATION;

			m_destTrackdirs = (TrackdirBits)(GetTileTrackStatus(v->dest_tile, TRANSPORT_RAIL) & TRACKDIR_BIT_MASK);

		}

		CYapfDestinationRailBase::SetDestination(v);

	}

	/// Called by YAPF to detect if node ends in the desired destination

	FORCEINLINE bool PfDetectDestination(Node& n)

	{

		bool bDest;

		if (m_dest_station_id != INVALID_STATION) {

		} else {

		}

		return bDest;

	}

	/** Called by YAPF to calculate cost estimate. Calculates distance to the destination

	*   adds it to the actual cost from origin and stores the sum to the Node::m_estimate */

	FORCEINLINE bool PfCalcEstimate(Node& n)

	{

		static int dg_dir_to_x_offs[] = {-1, 0, 1, 0};

		static int dg_dir_to_y_offs[] = {0, 1, 0, -1};

		if (PfDetectDestination(n)) {

			n.m_estimate = n.m_cost;

			return true;

		}

		TileIndex tile = n.GetLastTile();

		DiagDirection exitdir = TrackdirToExitdir(n.GetLastTrackdir());

		int x1 = 2 * TileX(tile) + dg_dir_to_x_offs[(int)exitdir];

		int y1 = 2 * TileY(tile) + dg_dir_to_y_offs[(int)exitdir];

		int x2 = 2 * TileX(m_destTile);

		int y2 = 2 * TileY(m_destTile);

		int dx = abs(x1 - x2);

		int dy = abs(y1 - y2);

		int dmin = min(dx, dy);