Global illumination is an important element for realistic image synthesis, but its computation is expensive and highly dependent on the complexity of the scene and of the BRDF of the involved surfaces. Last year, we presented a new approach to compute indirect lighting in real-time that is based on a discrete voxel representation of the scene geometry and reflected radiance. In this approach, we proposed a new volumetric cone-tracing algorithm that is used to efficiently gather indirect lighting and evaluate indirect visibility, and takes advantage of a hierarchical sparse voxel octree data structure. In this talk, we will first present an overview of the technique and then describe the latest advances and results of these researches related to the fast voxelization and octree construction for dynamic scenes, the management of multiple light bounces as well as the efficient implementation on Kepler hardware.
Discrete voxel representations are generating growing interest in a wide range of applications in computational sciences and particularly in computer graphics. A new real-time usage of dynamic voxelization inside a sparse voxel octree is to compute voxel-based global illumination. When used in real-time contexts, it becomes critical to achieve fast 3D scan conversion (also called voxelization) of traditional triangle-based surface representations. This talk describes an new surface voxelization algorithm that produces a sparse voxel representation of a triangle mesh scene in the form of an octree structure using the GPU hardware rasterizer. In order to scale to very large scenes, our approach avoids relying on an intermediate full regular grid to build the structure and constructs the octree directly.