Placement automatique de sondes d’irradiance
Diffuse global illumination within a 3D scene can be approximated in real time using irradiance probes. Probe placement typically relies on significant human input, and final quality of the approximation is often left to the subjectivity of a lighting artist. As demand for realism in rendering increases, the need to enhance the quality of such approximations is greater. We propose a method to automatically place probes in a scene by minimizing an error function. We guide probes to optimal sampling locations by applying gradient descent to an error function that represents similarity between our interpolated results and reference irradiance values. Using weighted nearest neighbour interpolation, we were able to reliably construct probe sets with minimal input in three scenes. Comparing our results to those produced by a set of probes placed on a 3D grid, we were theoretically successful in one scene, in which we could obtain lower error values with fewer probes. We obtained partial success in the other scenes, depending on the number of samples used.
Irradiance illumination globale Rendering Global illumination Light probes Interpolation Sampling