this weekend I could get implemented all the blender difuse shader models for volumetrics
(Lambert,Oren-Nayar,Blinn,Minaert,Fresnell) and also took some time for implementing an
aproximation (I have to note that is not the exact physical model in order to gain more user
control) of multiple ligth scattering using a simple scatter model, a Raileigh model and a
simplified Mie scatter model, the user could tweak the result.
Although not physically accurate, it will be useful for some effects.
Also add a new composite model for transparent volumetrics.
I’ll try to upload content soon.