Efficient algorithm for real-time generation of reflection lines

Depending upon the method of the surface generation and the quality of the designed boundary curves, the resulting surfaces may have global or local i rregularities in many cases. Thus, it would be necessary for the designer t o evaluate the surface quality and to modify the surface. This is very impo rtant because the defect of the surface causes the rework of the dies, incr easing cost and delivery time significantly. To simulate the reflection line test in the actual production line, a faste r algorithm for generating reflection lines is presented. In this paper, am ong various surface interrogation methods using reflection lines, Blinn-New ell type of reflection mapping is applied to generate the reflection lines on the trimmed NURBS surfaces. The derivation of reflection lines is formul ated as a surface-plane intersection problem (Jung 1994) and is solved by s urface-contouring techniques. Also, for eliminating the discontinuity of re flection lines due to the configuration of reflection map. a modified refle ction map is proposed. An efficient traced contouring technique is utilized for the computational efficiency and proves to be well suited for the real -time quality-assessment task.