18 double const aperture,
19 double const aperture_cutoff)
21 if (aperture >= aperture0)
27 if (aperture > aperture_cutoff)
29 double const penalty = std::log(aperture / aperture0);
30 return 1 + penalty * penalty +
31 2 * penalty / aperture * (aperture - aperture0);
36 double const penalty = std::log(aperture_cutoff / aperture0);
37 return 1 + penalty * penalty +
38 2 * penalty / aperture_cutoff *
39 (2 * aperture - aperture_cutoff - aperture0);