| 摘要 |
PROBLEM TO BE SOLVED: To provide a navigation system which makes a gradient of road ahead recognizable, without the sense of incongruity. SOLUTION: For an uphill slope of road ahead, a process controller sets a virtual horizontal line H1 and a vanishing point P1 determined by a depression angle, as shown in (b), and draws a level road to an approximate boundary d toward the vanishing point P1 from both sides of the running road. It then sets a virtual horizontal line H2, above the line H1 and a vanishing point P2 thereon and draws an uphill road from the approximate boundary d to the vanishing point P2. For a downhill slope of road ahead, the process controller sets a virtual horizontal line H1 and a vanishing point P1, a shown in (d), and draws a level road to an approximate boundary d from both sides of the running road. It then sets a virtual horizontal line H2 below the line H1 and a vanishing point P2 thereon, and draws downhill road from the approximate boundary d to the vanishing point P2. |
