All-Frequency Relighting of Non-Diffuse Objects using Separable BRDF Approximation

This paper presents a technique, based on pre-computed light transport and separable BRDF approximation, for interactive rendering of non-diffuse objects under all-frequency environment illumination. Existing techniques using spherical harmonics to represent environment maps and transport functions are limited to low-frequency light transport effects. Non-linear wavelet lighting approximation is able to capture all-frequency illumination and shadows for geometry relighting, but interactive rendering is currently limited to diffuse objects. Our work extends the wavelet-based approach to relighting of non-diffuse objects. We factorize the BRDF using separable decomposition and keep only a few low-order approximation terms, each consisting of a 2D light map paired with a 2D view map. We then pre-compute light transport matrices corresponding to each BRDF light map, and compress the data with a non-linear wavelet approximation. We use modern graphics hardware to accelerate precomputation....

• Type: Conference
• Year: 2004
• Where: RT
• Authors: Rui Wang 0003, John Tran, David P. Luebke
• Keywords: Light Transport, Low-frequency Light Transport, Pre-computed Light Transport, RT 2004