Large ray packets for real-time Whitted ray tracing

Abstract

In this paper, we explore large ray packet algorithms for acceleration structure traversal and frustum culling in the context of Whitted ray tracing, and examine how these methods respond to varying ray packet size, scene complexity, and ray recursion complexity. We offer a new algorithm for acceleration structure traversal which is robust to degrading coherence and a new method for generating frustum bounds around reflection and refraction ray packets. We compare, adjust, and finally compose the most effective algorithms into a real-time Whitted ray tracer. With the aid of multi-core CPU technology, our system renders complex scenes with reflections, refractions, and/or point-light shadows anywhere from 4–20 FPS.