| 摘要 |
PROBLEM TO BE SOLVED: To display a three-dimensional map in an entire display area with a relatively small load.SOLUTION: As a map database, a fine model database 17 for expressing features and a simple model database 16 for simply expressing the features are prepared. In displaying a three-dimensional map, the simple model is used to draw a simple three-dimensional map in all display areas, and for a fine model drawing range within a prescribed distance from a viewing point, a fine model is used with respect to a different layer to draw a fine three-dimensional map. Then, the fine three-dimensional map is superimposed on a front face of the simple three-dimensional map to synthesize the three-dimensional map, and the three-dimensional map is displayed. In this case, an area around a boundary of the fine model drawing range is semi-transparently drawn to thereby fuse both of the three-dimensional map and the area around the boundary without a discomfort sense. Further, when the viewing point is present in an area around a boundary area where the fine model is adjusted, an entire fine mode is semi-transparently drawn, and thereby, the fine three-dimensional map is gradually transmitted, which in turn can transit to the simple three-dimensional map without the discomfort sense.SELECTED DRAWING: Figure 1 |
