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diff --git a/src/pathfinder/pathfinder_func.h b/src/pathfinder/pathfinder_func.h
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+++ b/src/pathfinder/pathfinder_func.h
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+/* $Id$ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/** @file pathfinder_func.h General functions related to pathfinders. */
+
+#ifndef PATHFINDER_FUNC_H
+#define PATHFINDER_FUNC_H
+
+#include "../station_base.h"
+#include "../waypoint_base.h"
+
+/**
+ * Calculates the tile of given station that is closest to a given tile
+ * for this we assume the station is a rectangle,
+ * as defined by its tile are (st->train_station)
+ * @param station The station to calculate the distance to
+ * @param tile The tile from where to calculate the distance
+ * @return The closest station tile to the given tile.
+ */
+static inline TileIndex CalcClosestStationTile(StationID station, TileIndex tile)
+{
+	const BaseStation *st = BaseStation::Get(station);
+
+	/* If the rail station is (temporarily) not present, use the station sign to drive near the station */
+	if (st->train_station.tile == INVALID_TILE) return st->xy;
+
+	uint minx = TileX(st->train_station.tile);  // topmost corner of station
+	uint miny = TileY(st->train_station.tile);
+	uint maxx = minx + st->train_station.w - 1; // lowermost corner of station
+	uint maxy = miny + st->train_station.h - 1;
+
+	/* we are going the aim for the x coordinate of the closest corner
+	 * but if we are between those coordinates, we will aim for our own x coordinate */
+	uint x = ClampU(TileX(tile), minx, maxx);
+
+	/* same for y coordinate, see above comment */
+	uint y = ClampU(TileY(tile), miny, maxy);
+
+	/* return the tile of our target coordinates */
+	return TileXY(x, y);
+}
+
+#endif /* PATHFINDER_FUNC_H */