Three-dimensional CAD system and recording medium for three-dimensional CAD system

Abstract

According to the 3D-CAD system of the present invention, basic graphic elements (PL, LL, SL, VL) are set based on linear, area or volume coordinate parameters, and the plurality of basic graphic elements are continuously connected to generate a basic graphic. The basic graphic elements constituting the generated basic graphic are continuously differentiable even after deformation, thereby generating a desired solid graphic (identical topology graphic). By using these patches for approximately expressing all surfaces, the surfaces are handled consistently, the data quantity describing the graphics is greatly reduced, and the load of operational processing of the computer is reduced. Whether or not an element can be deleted is determined based on a reference counter RC showing whether said element is the component of another element.

Dependencies are inferred from the claim text.