The ray tracing algorithm is adopted to complete the realistic graphical generation for a NC turning machining center and it’s processing simulation is realized in off line. In the simulation

on the basis of characteristics in NC processing

the Torrance-Sparrow’s illumination model is simplified and the complicated Boolean operation is avoided using the feature model technology. Since the main task in the ray tracing is to calculate intersection points

a new method is designed based on a convex polyhedron constraint condition and the Cyrus-Beck’s algorithm for line clipping. The method is not only efficient

but it can lead to the test and the intersection calculation between a ray and an arbitrary convex polyhedron. In the end

the possibility to generate an real time fidelity scenario based on ray tracing method is discussed.