| 摘要 |
PROBLEM TO BE SOLVED: To prevent a course display from disappearing from a screen even when a moving body is greatly dislocated from a set course, by shifting display range in a direction parallel to the course in accordance with the moving amount of the course direction component of the moving body. SOLUTION: The position of a moving body, e.g. one's own ship S is displayed in a course up mode wherein a line connecting a destination B and the moving body is set as a course CO and the destination B is set at an upper part on a screen. At the same time, a make of the ship S is displayed so that the present position of the ship S and a line L in a fixed direction shifted from the course overlap within the screen. If the ship S shifts as it moves, while the course CO is still kept to be in the up/down direction of the screen, a display range is shifted along the course CO in accordance with the moving amount of a course directional component of the ship S to make the present position of the ship S overlap with a point in the shifted direction. Since coast lines C1 , C2 and the destination B are moved parallel to the course CO, a positional relationship between the ship S and the course CO is clear at all times. |
