Second-Order Feed-Forward Renderingfor Specular and Glossy Reflections

IEEE Trans Vis Comput Graph. 2014 Sep;20(9):1316-29. doi: 10.1109/TVCG.2014.2314666.

Abstract

The feed-forward pipeline based on projection followed by rasterization handles the rays that leave the eye efficiently: these first-order rays are modeled with a simple camera that projects geometry to screen. Second-order rays however, as, for example, those resulting from specular reflections, are challenging for the feed-forward approach. We propose an extension of the feed-forward pipeline to handle second-order rays resulting from specular and glossy reflections. The coherence of second-order rays is leveraged through clustering, the geometry reflected by a cluster is approximated with a depth image, and the color samples captured by the second-order rays of a cluster are computed by intersection with the depth image. We achieve quality specular and glossy reflections at interactive rates in fully dynamic scenes.