In this invention, letters that can be seen by a pedestrian (101) are drawn on an intersection (103). A mark (MM2) that can be seen by the driver of the host vehicle (C) is drawn on the road (104) between the intersection (103) and the host-vehicle (C). The shapes of the letters (MO4) are corrected in accordance with the positional relationship between the pedestrian (101) and the intersection (103). The shape of the mark (MM2) is corrected in accordance with the positional relationship between the driver of the host-vehicle (C) and the road (104).