example usage of ArHosek12 and ArPrague21

effect:

A chart with full-colour renditions of the proposed model for a ground albedo of zero, for turbidities 1 (topmost row) to 10 (bottom row).

reference

ArHosek12

An Analytic Model for Full Spectral Sky-Dome Radiance https://cgg.mff.cuni.cz/projects/SkylightModelling/
- https://gitlab.com/art-development-team/ART/-/blob/master/Source/Foundation/Physics/ArHosekSkyModel_ART_frontend.c
pbrt imgtool/makesky https://github.com/mmp/pbrt-v4/blob/master/src/pbrt/cmd/imgtool.cpp
githole/Skydome: An Analytic Model for Full Spectral Sky-Dome Radiance https://github.com/githole/Skydome

ArPrague21

A Fitted Radiance and Attenuation Model for Realistic Atmospheres https://cgg.mff.cuni.cz/publications/skymodel-2021/
- https://gitlab.com/art-development-team/ART/-/blob/master/Source/Foundation/Physics/ArPragueSkyModel_ART_frontend.c
PetrVevoda/pragueskymodel: Prague Sky Model https://github.com/PetrVevoda/pragueskymodel

other

Simple Analytic Approximationsto the CIE XYZ Color Matching Functions (JCGT) https://jcgt.org/published/0002/02/01/
- Pete Shirley's Graphics Blog: Converting Spectra to XYZ/RGB values https://psgraphics.blogspot.com/2014/11/converting-spectra-to-xyzrgb-values.html