| 摘要 |
PURPOSE: To display an optimum route and a traffic information route over a road displayed as a bird's-eye view without damaging a sense of distance by displaying the route with a broken line whose dashes have the width and intervals corresponding to the distance from the viewpoint on the road map in the bird's-eye view system. CONSTITUTION: A CPU converts road map data of a two-dimensional plane read to road map data in the bird's-eye view system and displays an optimum road and a traffic information route over the road map in the bird's-eye view system. At this time, the CPU reads in one link data on the route and calculates the middle point of this link. A road is converted to data by nodes indicating intersections and bending points and links connecting the nodes. The distance from the middle point of the link to the viewpoint on the road map in the bird's-eye view system is calculated, and the width and intervals of dashes of a broken line are obtained in accordance with this calculated distance by a prescribed formula. The roud is plotted with the broken line whose dashes have calculated width and intervals. |
