Non-uniform illumination-guided probe placement

Abstract:
In real-time rendering, the probe-based global illumination algorithms are one of the most widely used algorithms to produce indirect diffuse illumination. In most algorithms, probes are placed uniformly in the scene volume, resulting in memory waste, or even incorrect shading results due to probes inside the object. This paper presents a non-uniform illumination-guided probe placement method. Our algorithm performs gradient descent on the irradiance errors between the probe and its surrounding shading points to drive the placement of the probe. We also propose a local distance variance to prevent the probe from getting too close to the object surface. Experimental results demonstrate that our algorithm can achieve similar rendering results to DDGI (Dynamic Diffuse Global Illumination) with fewer probes.