Three-dimensional model generation system, three-dimensional model generation method, and recording medium storing a three-dimensional model generation program

A three-dimensional model generation method of generating a three-dimensional model, comprising the steps of:

• designating an edge with respect to which a fillet or a chamfer is to be generated;
• generating said fillet or said chamfer at a location of said designated edge;
• and
• storing data concerning said edge erased as a result of said generation of said fillet or said chamfer, as data of a former edge associated with a feature of said fillet or chamfer.

A three-dimensional model generation method of generating a three-dimensional model, comprising the steps of:

• designating a fillet or a chamfer;
• obtaining data of a former edge stored in association with a feature of said fillet or said chamfer which is designated;
• generating three-dimensional display data from said data of said former edge;
• and
• displaying said three-dimensional display data, for selection, in a manner such that said former edge data can be dealt in the same manner as a normal edge is dealt with.

A two-dimensional drawing generation method of generating a two-dimensional drawing by projecting a three-dimensional model onto a two-dimensional plane, comprising the steps of:

• designating a fillet or a chamfer;
• generating a two-dimensional projection drawing by using geometry data stored in association with a feature of said fillet or said chamfer designated;
• generating projection drawing data by using data of a former edge stored in association with said feature of said fillet or said chamfer;
• and
• generating a projection drawing of said edge, based on said generated projection drawing data.

A computer-readable recording medium storing a program for generating a three-dimensional model, said program including geometry-generating/editing means which is capable of changing an edge of a three-dimensional model into a fillet or a chamfer, feature management means for associating geometry data items with respective features generated or edited by said geometry-generating/editing means on a feature-by-feature basis, and when any of said features is a fillet or a chamfer, associating data of an edge erased as a result of generation of said fillet or chamfer as data of a former edge data associated with said fillet or said chamfer, for storage in three-dimensional data storage means, as well as for obtaining any of said geometry data items stored in association with a corresponding one of said respective features from said three-dimensional data storage means, in response to a request sent from said geometry-generating/editing means for obtaining three-dimensional data of said any of said features, former edge data management means for generating three-dimensional display data from said data of said former edge obtained by said feature management means from said three-dimensional data storage means in response to a request sent from said geometry-generating/editing means to said feature management means for obtaining three-dimensional data of said feature of said fillet or said chamfer, and two-dimensional drawing generation means for generating a two-dimensional drawing based on said any of geometry data items of said three-dimensional model.