To me that would be Appleseed rendering engine. https://github.com/appleseedhq/appleseed https://github.com/appleseedhq/appleseed Even though I can't code C++

To me that would be Appleseed rendering engine. https://github.com/appleseedhq/appleseed https://github.com/appleseedhq/appleseed Even though I can't code C++, I can read it here and understand most of it (besides the maths).