| 摘要 |
PURPOSE: To enhance the function of a three-dimensional model producing device for producing three-dimensional expressions by providing a pointing means which defines the first and second surfaces of a solid from first and second twodimensional drawings and displaying the two-dimensional drawings as a solid on a graphic displaying device by deforming the drawings. CONSTITUTION: A user is instructed to select a specific surface to be displayed in a functional block 1810. The user selects the surface by instructing a plane with a cursor and selecting an appropriate surface from a CADAM database using the coordinates of a pointer. Then the selected surface is erased and surface data are rearranged in a functional block 1830. Four kinds of surface data, namely, a ruled surface, a plane of rotation, a boundary surface, and a skin surface can be rearranged. For the ruled surface or plane of rotation, the order of control points is reversed and the knot sequence of the spline is calculated. For the boundary surface, the control points of the spline are inverted and the knot sequence is recalculated. Finally, the surface selected in a functional block 1840 is shaded. |
