Debug FourierBSDF::sample_f(...)

[wahn]

Let's debug the Rust version of FourierBSDF::sample_f(...) by single stepping trough C++ and Rust until we identify what's going wrong ...

[wahn]

Since aa0c2c9 the FourierBSDF::sample_f(...) seems to be fine. Let's focus on FourierBSDF::f(...) now:

reflection.cpp:763
0.121142946, 0.121143118, 0.121142946
reflection.rs:372
5.00299358, 5.00300455, 5.00299358

[wahn]

Closing after commit e7ab8e5 ...