Fullsphere Irradiance Factorization for Real‐Time All‐Frequency Illumination for Dynamic Scenes

Computation of illumination with soft‐shadows from all‐frequency environment maps, is a computationally expensive process. Use of pre‐computation add the limitation that receiver's geometry must be known in advance, since Irradiance computation takes into account the receiver's normal direction. We propose a method that using a new notion that we introduce, the Fullsphere Irradiance, allows us to accumulate the contribution from all light sources in the scene, on a possible receiver without knowing the receiver's geometry. This expensive computation is done in a pre‐processing step. The pre‐computed value is used at run time to compute the Irradiance arriving at any receiver with known direction. We show how using this technique we compute soft‐shadows and self‐shadows in real‐time from all‐frequency environments, with only modest memory requirements. A GPU implementation of the method, yields high frame rates even for complex scenes with dozens of dynamic occluders and receivers.