Ray tracing objects defined by sweeping planar cubic splines

The crucial step in a program based on ray tracing is the calculation of the intersection of a line with an object. In this paper, algorithms are presented for performing this calculation for objects defined by sweeping a planar cubic spline through space. Translational, rotational, and conic sweeping are treated. Besides solutions for the exact calculation, rectangle tests for improving efficiency are given. Possible extensions and improvements are discussed