Efficient Animation of Sparse Voxel Octrees for Real-Time Ray Tracing
A considerable limitation of employing sparse voxels octrees (SVOs) as a model format for ray tracing has been that the octree data structure is inherently static. Due to traversal algorithms' dependence on the strict hierarchical structure of octrees, it has been challenging to achieve real-time performance of SVO model animation in ray tracing since the octree data structure would typically have to be regenerated every frame. Presented in this article is a novel method for animation of models specified on the SVO format. The method distinguishes itself by permitting model transformations such as rotation, translation, and anisotropic scaling, while preserving the hierarchical structure of SVO models so that they may be efficiently traversed. Due to its modest memory footprint and straightforward arithmetic operations, the method is well-suited for implementation in hardware. A software ray tracing implementation of animated SVO models demonstrates real-time performance on current-generation desktop GPUs, and shows that the animation method does not substantially slow down the rendering procedure compared to rendering static SVOs.