| 摘要 |
PURPOSE:To generate a three-dimensional figure from a figure generated on a two-dimensional drawing through easy operation by indicating an object closed area, the definition of a surface shape, and elements defining the surface shape, and then defining the surface shape of the object closed area. CONSTITUTION:The graphic is made into a closed area S2 while the continuity relation, connection state, etc., of graphic elements such as segments and arcs of the graphic on the drawing are checked. An optional closed area in the graphic made into the closed area is indicated S3. When one optional point is indicated according to the indication, the inside/outside relation between each closed area and the indicated point is decided and the closed area which include the indicated point is recognized S4 as the indicated closed area. Then the elements defining the surface shape of the indicated closed area are indicated S5. The closed area as an object of surface shape definition, the definition of the surface shape, and the elements defining the surface shape are determined by the processes, so a mathematical expression which shows the surface shape is derived and defined S6 as the surface shape of the object closed area. |
