Existing methods to create contour files generate a polygonal approximation of
the contours instead of an exact representation. This paper presents a method to generate
exact contours from Constructive Solid Geometry (CSG) representations. The method
preserves the accuracy of the contour files provided the primitives used to generate the
CSG tree are polygonal or quadric objects. Due to the inclusion of quadric objects into
the primitive set an additional effort to solve for the intersection points between two
quadric curves is required. The paper also presents a method to convert piecewise
quadratic contours to toggle point files for raster scanning solid freeform fabrication
processes.Mechanical Engineerin
