(svn r14921) -Fix [FS#2507]: Do not try to calculate a center of a train-station, when there is none.

src/npf.cpp

@@ -101,6 +101,9 @@ static TileIndex CalcClosestStationTile(StationID station, TileIndex tile)
 {
 	const Station* st = GetStation(station);
 
+	/* If the rail station is (temporarily) not present, use the station sign to drive near the station */
+	if (!IsValidTile(st->train_tile)) return st->xy;
+
 	uint minx = TileX(st->train_tile);  // topmost corner of station
 	uint miny = TileY(st->train_tile);
 	uint maxx = minx + st->trainst_w - 1; // lowermost corner of station

src/yapf/yapf_destrail.hpp

@@ -119,6 +119,9 @@ protected:
 	{
 		const Station* st = GetStation(station);
 
+		/* If the rail station is (temporarily) not present, use the station sign to drive near the station */
+		if (!IsValidTile(st->train_tile)) return st->xy;
+
 		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