Patent ID: 7653517

Claim:
A computer-based design shape generating apparatus for generating a new design shape of an article by performing a shape transformation process, using a transformation processing device, with respect to a design shape of the article which has been already generated, the apparatus comprising: an input device receiving transformation instructions from an operator; and the transformation processing device performing an operation of the design shape which has been already generated in accordance with the transformation instructions, wherein the input device receives input for designating a shape attribute of the article between a transformation region for which the shape transformation process is to be performed and a maintaining region which maintains its shape, and input of a transformation instruction vector which is defined by a direction and an amount of transformation with respect to the article, and wherein the transformation processing device is configured to: not displace a node located at a boundary between the transformation region and the maintaining region; subdivide the transformation region into a plurality of shape elements; and displace a node defining the shape of the shape elements and belonging only to the transformation region in accordance with the input transformation instruction vector as follows: when the node is located on a single bending line of the article, the bending line being an intersection of a surface of a first shape element and a surface of a second shape element that meet at an intersection angle other than 180 degrees, the input device further receives an input of a predetermined angle, and when an angle, formed by the transformation instruction vector and a bending line vector being an extension of the bending line, is less than the predetermined angle, the node is displaced in a direction of the bending line vector and by an amount corresponding to a component of the input transformation instruction vector in the direction of the bending line vector, and when the angle formed by the transformation instruction vector and the bending line vector is equal to or greater than the predetermined angle, the node is displaced in accordance with the transformation instruction vector, when the node is located on the intersection of a plurality of bending lines of the article, the node is displaced in the direction of the bending line vector which forms the smallest angle with respect to the transformation instruction vector and by an amount corresponding to a component of the input transformation instruction vector in the direction of the bending line vector, and when the node is not located on the bending line of the article, the node is displaced in accordance with a vector obtained by projecting the transformation instruction vector onto an extension plane of an article shape plane at that node.