| 摘要 |
<p>Ray tracing complicated curved surfaces encounters many problems caused by the inability of the existing techniques to adaptively compute the ray and surface intersections based on the image precision of the tracing. Disclosed is a method which uses beams (PB) to trace curved surfaces (SU). Each beam (PB) contains several corner rays and optionally a central ray (PR). Working in synergy, the central ray (PR) allows fast detection of the intersecting patch while the corner rays enable estimation of the image size of the patch. Using this strategy, the method can adaptively subdivide surfaces based on the image characteristics of patches during tracing. It further reduces the computation requirement of this subdivision by using caches which store the information of patches and vertices, and carrying out the tracing in a sequence that maximizes the coherence of these caches.</p> |
