FWIW, the book gives a more detailed description of the assumptions/limitations of pbrt here: http://www.pbr-book.org/3ed-2018/Color_and_Radiometry/Radiometry.h

FWIW, the book gives a more detailed description of the assumptions/limitations of pbrt here: http://www.pbr-book.org/3ed-2018/Color_and_Radiometry/Radiometry.html http://www.pbr-book.org/3ed-2018/Color_and_Radiometry/Radiom... E.g. it doesn't handle things like polarization, interference or fluorescence, assumes light is instantaneous, etc.