Function pyramid_setup 

pub unsafe extern "C" fn pyramid_setup(
    this: *mut pyramid,
    N_PX_PUPIL: c_int,
    _N_PUPIL_SAMPLING_: c_int,
    _modulation_: f32,
    _modulation_sampling_: c_int,
    _alpha_: f32,
    N_GS: c_int,
)