Stochastic Progressive Photon Mapping
Physically Based Rendering: http://www.codinglabs.net/article_physically_based_rendering_cook_torrance.aspx
Physically Based Rendering - Cook–Torrance: http://www.codinglabs.net/article_physically_based_rendering_cook_torrance.aspx
SPPM Framework: https://github.com/shizhouxing/SPPM
Bezier + Texture: https://github.com/Trinkle23897/Computational-Graphics-THU-2018
PPM: https://github.com/zhengpingzhou/PPM
Denoising: http://rcm.cps.utexas.edu/