high performance computing on graphics processing units: hgpu.org

Illumination rendering including environment lighting, indirect illumination, and subsurface scattering plays for many graphics applications such as games and VR systems. However, it is dificult to run in real-time due to its highly computational cost. We introduce a GPU-based light hierarchy for real-time approximation of the illumination. We store virtual point lights in images and then build the view-independent hierarchy of the lights into image pyramids, with a simple and rapid clustering strategy. We approximate the illumination with small numbers of groups of lights instead of large numbers of individual lights, using a new tree traversal algorithm on programmable graphics hardware. Although we implemented our method without occlusion, we obtained visually-good results in many cases. Entire steps run on programmable graphics hardware in real-time without any preprocessing.