Change `5layer_atmosphere` interface to take magnetic field callable.
The new 5layer_atmosphere
, take a fixed magnetic field vector as far as I'm aware. For large scale air shower simulations (i.e. stratospheric or orbital detectors like ANITA/POEMMA), the showers can be so long that they experience a magnetic field vector that changes significantly over the shower length.
I'd like to change the interface so that you give a callable to 5layer_atmosphere
that takes the particle position and returns the magnetic field. For constant simulations, I'm guessing the compiler will just inline it via RVO but we can check to make sure.