| 摘要 |
PURPOSE:To execute the deletion processing of the implicit line of each polygon at the time of displaying a birds-eye viewing figure from an arbitrary point of view on plural polygons. CONSTITUTION:The projections of the polygon on the bottom of each polygon is decided (A1). The coordinate conversion is performed on a viewing plane against every polygon according to the view point designated in advance (A2). Further, the visibility and invisibility on every polygon is decided, and the self implicit line which is the boundary ridge line of the invisible surfaces is eliminated (A3 and A4). After the implicit line deletion of each recessed polygon (A5), the implicit line deletion is performed on the whole polygon (A6). |
