A GPU-Based Light Hierarchy
for Real-Time Approximate Illumination
light pyramids

Illumination rendering including environment lighting, indirect illumination, and subsurface scattering plays an important role for many graphics applications such as games and VR systems. However, it is difficult 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.

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Selected Publication:
A GPU-Based Light Hierarchy for Real-Time Approximate Illumination Hyunwoo Ki, and Kyoungsu Oh. "A GPU-Based Light Hierarchy for Real-Time Approximate Illumination". The Visual Computer, Volume 24, Numbers 7-9, July, 2008, pp. 649-658.

BibTeX:
@article{KiH08LP,
author = {Hyunwoo Ki and Kyoungsu Oh},
title = {A GPU-Based Light Hierarchy for Real-Time Approximate Illumination},
journal = {The Visual Computer},
volume = {24},
number = {7-9},
month = {July},
year = {2008},
pages = {649--658}, }

Acknowledgement:
We would like to very thank to Carsten Dachsbacher to allow us to use his refective shadow maps code. We also thank to the AIM@SHAPE Shape Repository and 3D model creators.


Related Publication:
Hierarchical Rendering Techniques for Real-Time Approximate Illumination on Programmable Graphics Hardware Hyunwoo Ki. "Hierarchical Rendering Techniques for Real-Time Approximate Illumination on Programmable Graphics Hardware". Master's Thesis, Soongsil University, June 2007. (Note this thesis is an extended version of the journal paper. It additionally introduces a hierarchical subsampling method to accelerate final rendering.)

Related Work (External):
- Carsten Dachsbacher and Marc Stamminger. "Reflective Shadow Maps". 2005 ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games.