Ray Tracing Dynamic Scenes Using Multiple Kd-trees

Abstract

With faster hardware and algorithmic improvements, real-time ray tracing is finally within reach. A variety of different data structures have been developed for ray tracing over the past decades. These spatial data structures crucial for fast ray tracing must be rebuilt or updated as the scene changes, and this can become a bottle-neck for the speed of ray tracing. In this paper, a novel algorithm is proposed to improve the rendering speed for static and moving objects by build kd-trees respectively, i.e., we construct multiple kd-trees. This building method allows for ray tracing animations without rebuilding the spatial index structures for the whole scene, just for dynamic objects. We implement the proposed algorithm for ray tracing dynamic scene on CPU+GPU platform, resulting in frame rates of 3~5 fps for 1024*1024 images, which improves rendering speed of dynamic scenes significantly.