METHOD AND DEVICE FOR PLOTTING THREE-DIMENSIONAL FIGURE, AND STORAGE MEDIUM WITH PROGRAM OF THREE-DIMENSIONAL FIGURE PLOTTING METHOD STORED THEREIN

摘要

PROBLEM TO BE SOLVED: To make a CAD operation efficient by generating the rotation center of a three-dimensional shape at an appropriate position. ;SOLUTION: When a rotation instruction is made to a three-dimensional figure projected and displayed on a display screen 3, points included in the threedimensional shape SG are turned to be projected on a projection surface Ha. Then, a distance between each point existing in the inner projection surface of the projected point and a reference surface Hb which is a plane, that is parallel to the surface Ha and goes through the origin of XYZ coordinates is calculated. The mean value of all calculated distances is generated. Meanwhile, the position obtained by moving the center point of the surface Ha in the perpendicular direction by the mean value from a point, where the center point is projected onto the surface Hb is defined as the turning center of the shape SG. When a designer rotates the three-dimensional figure by an operation the next time is this way, operation man-hours can be reduced while a part desired to be looked at is prevented from being removed from the display screen.;COPYRIGHT: (C)2001,JPO