Partial reprojection method and device in three-dimensional CAD system and computer program

A partial reprojection device for reflecting a shape modified in a part model on a two-dimensional projection that is generated from an assembly model in a three-dimensional CAD system, the device comprising a reprojection processing portion for controlling a partial reprojection process and a modeling kernel for performing processes including a contour line process and a hidden line process, wherein the reprojection processing portion includes

• an associative analysis processing portion for analyzing information of the two-dimensional projection to be reprojected;
• a drawing processing portion for deciding three-dimensional elements to be projected in association with the modeling kernel from three-dimensional shape data and a projection condition;
• a drawing data generation processing portion for generating the decided three-dimensional elements as two-dimensional elements on the drawing;
• and
• an associative setting processing portion for grouping the generated two-dimensional elements for each part and for setting a relationship with conditions and the models.

A computer program product for use in a three-dimensional CAD system for enabling reflection of a shape modified in a part model on a two-dimensional projection generated from an assembly model, the computer program product comprising:

• means for grouping elements projected from the assembly model for each part;
• means for adding attributions of each part information to the two-dimensional projection, the attributions including a line of sight and a position of the part;
• and
• means for specifying two-dimensional elements to be updated when updating the shape in the part model, so as to decide a projecting direction of the part model from the line of sight of each part included in the part information and to decide a generating position of the two-dimensional elements from the position of the part included in the part information.

A recording medium that can be read by a computer and stores a computer program for a three-dimensional CAD system that enables reflection of a shape modified in a part model on a two-dimensional projection generated from an assembly model, the computer program making a computer perform the process comprising the steps of:

• grouping elements projected from the assembly model for each part;
• adding attributions of each part information to the two-dimensional projection, the attributions including a line of sight and a position of the part;
• and
• specifying two-dimensional elements to be updated when updating the shape in the part model, so as to decide a projecting direction of the part model from the line of sight of each part included in the part information and to decide a generating position of the two-dimensional elements from the position of the part included in the part information.