A simple ray-/pathtracer in cpp .
boost https://github.com/boostorg/boost stb (included as submodule) https://github.com/nothings/stb
@see:
https://raytracing.github.io/books/RayTracingInOneWeekend.html
https://raytracing.github.io/books/RayTracingTheNextWeek.html
https://raytracing.github.io/books/RayTracingTheRestOfYourLife.html
http://www.pbr-book.org/