Indirect illumination with efficient monte carlo integration and denoising

초록

Herein, an interactive, one-bounce, and indirect illumination algorithm that considers indirect visibility even in a fully dynamic scene is introduced. First, a small number of rays are randomly emitted on the hemisphere of the current pixel to obtain the first intersection point in a scene. If this point is directly illuminated by the light source, its illuminated color is collected by sampling the reflective shadow maps for gathering the indirect illumination. Second, to approximate indirect visibility, a three-dimensional ray marching algorithm (MRM) is used; the algorithm is based on a mipmap hierarchy structure generated by voxelizing the scene to accelerate the ray-voxel intersection. Third, images of indirect illumination are denoised by iterating an improved edge-avoiding filtering via a local means replacement method (LMR). Finally, variance-clip temporal filtering on the merged global illumination image is applied to further eliminate jitter. The implementation demonstrates that the algorithm used in this study can efficiently generate high-quality global illumination images.

키워드