@@ -111,7 +111,7 @@ void SetWaterClassDependingOnSurrounding
/* Mark tile dirty in all cases */
MarkTileDirtyByTile(t);
if (TileX(t) == 0 || TileY(t) == 0 || TileX(t) == MapMaxX() || TileY(t) == MapMaxY()) {
if (TileX(t) == 0 || TileY(t) == 0 || TileX(t) == MapMaxX() - 1 || TileY(t) == MapMaxY() - 1) {
/* tiles at map borders are always WATER_CLASS_SEA */
SetWaterClass(t, WATER_CLASS_SEA);
return;