Hi, TheJamsh!
Thanks for voting!
The item has been moved to the “Next Release” section of the Marketplace trello board recently, so I hope that it will be available very soon!
Actually, my implementation does take multiple samples and uses no HLSL code (only nodes). My implementation is based on this article: http://www.scratchapixel.com/old/lessons/3d-advanced-lessons/simulating-the-colors-of-the-sky/atmospheric-scattering/
The only way to accurately simulate scattering without using sample method is using precomputed lookup tables. I have tried to implement this, however, the amount of light that comes from any direction depends on four parameters: view height, view pitch, view yaw and sun angle. This requires a 4D table to store precompution results. Eric Bruneton’s GLSL implementation uses this method and uses a 3D texture to store the results: http://www-evasion.imag.fr/people/Eric.Bruneton/
UE4 however, doesn’t allow to use 3D textures easily. A semi-precomputed method is possible using just a two-dimentional table to store optical depth for all points (that only depends on view height and view pitch) and I had it prototyped. It required a separate program that I wrote in C to generate those tables and it didn’t allow to change parameters on the fly. Maybe I will finish it one day and in this case it will be a free update to my current implementation, but no promises for now!
Robert.