| 摘要 |
PURPOSE:To make it possible to expand effectively a map area in the direction of advance of a vehicle as well as a map area in the direction of a destination viewed from the current position by shifting the current position, together with a map, by a prescribed amount in a prescribed direction in accordance with a relative angle of each direction. CONSTITUTION:When a destination O is set on a map, the current position located in the center of a drawing is shifted together with the map by a prescribed amount and displayed on the opposite side to the destination viewed from the current position, in a prescribed direction in accordance with an angle formed by the direction of advance of the vehicle at the current position and the direction of the destination viewed from the current position, so that map areas in the direction of the destination viewed from the current position and also in the direction of advance of the vehicle be expanded on the drawing. By a data processing by a prescribed algorithm in a signal processing device 3, in other words, the current position is displayed at a point P' which is located on the bisector of the angle thetaformed by the direction of advance of the vehicle at the current position P and the direction of the destination O viewed from the current position P and which is obtained by a shift by a prescribed distance l from the center of the drawing onto the opposite side to the destina tion O. By this method, a map area in the direction of the destination viewed from the current position can be expanded. |
