Design of Piece Intersection-line Drawing System Based on VC

The CAD style of sheet metal piece may draw hardware working drawing with piece intersection line,but it is hard to draw the piece intersection line,especially inner piece intersection line because of computing critical points of eyeable inner intersection line.This paper takes three-way point of the cylinder for example to analyze and find the projection equations of the inner intersection lines in the its plan form and converts them into new ones in the world coordinates of AutoCAD,and then VC programs based on Objectarx is used to draw the inner intersection lines.