| 摘要 |
PROBLEM TO BE SOLVED: To automatically display both a current place and a destination when the destination, etc., is set by automatically changing the scale level of a map so that >=2 positions set on the map can be all displayed. SOLUTION: When a destination symbol is stored, a computer calculates a scale level Z1 and displays an irreducible area for displaying both the position Sv of a vehicle positioned in the center of a monitor and the destination symbol S. The distance between Sd and Sv is decomposed into orthogonal componentsΔX' andΔY'. To begin with a minimum window W0 (i.e., scale level Z0 ), the length is calculated and compared withΔX' until a scale level at which the length exceedsΔX' (i.e., positioning in the display window W). The two calculated minimum scale levels determine a proper scale level. When two positions are specified, a display including all the specified positions is made. |
