ExternalAssetReferences.txt

The textures: T_00_NewMoon_D, T_01_WaxingCrescentMoon_D, T_02_FirstQuarterMoon_D, T_03_WaxingGibbous_D, 
              T_04_FullMoon_D, T_05_WaningGibbous_D, T_06_LastQuarter_D and T_07_WaningCrescent_D have
			  being edited from the original "full-moon-496873_1920.jpg" obtained from:
			  https://pixabay.com/pt/lua-cheia-lua-brilhante-reino-unido-496873   
			  licensed under CC0 - creative commons, with no attribution required and for commercial use allowed.
			  The PSD (Photoshop files are being provided with each changes on the original) inside texture folder.

The T_Sky_Blue, T_Sky_Clouds_M, T_Sky_Stars textures are from Unreal Engine 4 Engine, originally used in the BP_Sky_Sphere blueprint.

The function Henyey-Greenstein-Phase is part of Unreal Engine 4 and it is not exposed in the library, it is replicated as-is to make it easier to find by novices.

Interpolation formulas used inside FL_Orchestrator library for Blueprints was obtained from the C++ code which is Open Source (BSD License) 
from: http://robertpenner.com/easing/   
and based on C++ code file found in the repository at GitHub: https://github.com/jesusgollonet/ofpennereasing 

The Volumetric Raymarching techniques used was based in insights from the Epic's stream https://forums.unrealengine.com/unreal-engine/events/116634-training-livestream-realtime-simulation-and-volume-modelling-experiments-may-2-live-from-epic  and from Ryan Bruck's blog http://shaderbits.com/blog/creating-volumetric-ray-marcher. Several techniques provided functions inside Unreal Engine 4 already and were used in Fortnite at some extent.
Several adaptations were made: cloud world positioning, cloud layers, erosion textures to add details, different LoD for erosion textures, 
cloud shadows at ground via Light Function, wind contribution system, network replication and feature called Evolution Orchestrator are all 
developed by Nilson Fernandes de Lima.