static const uint _trackdir_length[TRACKDIR_END] = {

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH,

	0, 0,

	NPF_TILE_LENGTH, NPF_TILE_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH, NPF_STRAIGHT_LENGTH

};

/**

 * Calculates the minimum distance traveled to get from t0 to t1 when only

 * using tracks (ie, only making 45 degree turns). Returns the distance in the

 * NPF scale, ie the number of full tiles multiplied by NPF_TILE_LENGTH to

 * prevent rounding.

 */

{

	const uint dx = abs(TileX(t0) - TileX(t1));

	const uint dy = abs(TileY(t0) - TileY(t1));

	const uint straightTracks = 2 * min(dx, dy); /* The number of straight (not full length) tracks */

	/* OPTIMISATION:

	 * Original: diagTracks = max(dx, dy) - min(dx,dy);

	 * Proof:

	 * (dx+dy) - straightTracks  == (min + max) - straightTracks = min + max - 2 * min = max - min */

	const uint diagTracks = dx + dy - straightTracks; /* The number of diagonal (full tile length) tracks. */

	/* Don't factor out NPF_TILE_LENGTH below, this will round values and lose

	 * precision */

	return diagTracks * NPF_TILE_LENGTH + straightTracks * NPF_TILE_LENGTH * STRAIGHT_TRACK_LENGTH;

}

/**

 * Check if a rail track is the end of the line. Will also consider 1-way signals to be the end of a line.

 * @param tile The tile on which the current track is.

 * @param trackdir The (track)direction in which you want to look.

 * @param enginetype The type of the engine for which we are checking this.

 */

{

	byte exitdir = TrackdirToExitdir(trackdir);

	TileIndex dst_tile;

	uint32 ts;

	/* Can always go into a tunnel */

	if (IsTileType(tile, MP_TUNNELBRIDGE) && (_m[tile].m5 & 0xF0)==0 && (_m[tile].m5 & 3) == exitdir)

		return false;

	/* Cannot go through the back of a depot */

	if (IsTileDepotType(tile, TRANSPORT_RAIL) && (exitdir != GetDepotDirection(tile, TRANSPORT_RAIL)))

		return true;

	// but if we are between those coordinates, we will aim for our own x coordinate

	x = clamp(TileX(tile), minx, maxx);

	// same for y coordinate, see above comment

	y = clamp(TileY(tile), miny, maxy);

	// return the tile of our target coordinates

	return TileXY(x, y);

}

/* On PBS pathfinding runs, this is called before pathfinding ends (BeforeExit aystar callback), and will

 * reserve the appropriate tracks, if needed. */

{

	NPFFoundTargetData* ftd = (NPFFoundTargetData*)as->user_path;

	bool eol_end = false;

	if (ftd->best_trackdir == 0xFF)

		return;

	if (!NPFGetFlag(&ftd->node, NPF_FLAG_PBS_EXIT) && IsEndOfLine(ftd->node.tile, ftd->node.direction, as->user_data[NPF_RAILTYPE]) && !NPFGetFlag(&ftd->node, NPF_FLAG_SEEN_SIGNAL)) {

		/* The path ends in an end of line, we'll need to reserve a path.

		 * We treat and end of line as a red exit signal */

		eol_end = true;

		NPFSetFlag(&ftd->node, NPF_FLAG_PBS_EXIT, true);