It is clear to Me that phong is best material to use on a gaming render engine, however it has its limitations for creating photorealism in an interactive environment.
the use fresnel for diffuse and Gloss/roughness channels for both dielectric and metal materials is what gives PBR its attributes for achieving best approximation on how materials physically work in real life....however I am not sure if via the phong shader it can actually render properly in Sansar.
I make the premise that I have not experimented with it and any heads up about it from any Linden Dev is welcome.
In case fresnel is limited or worse not supported by Umbra, i would kindly request, to have the ability to select faces just as it is done in Second Life and have the ability to use nodes to control fresnel, to control maps to add detail and nodes to add displacement depth on top of the normal maps via a bump/displacement node.
This would allow to add details like eg smudges with fresnel realism or dust on top the diffuse channel, on top of that further detail can be added to the normals channel so to create proper materials that are more accurate to real life.
It is also inevitable to mention that by the use stuff like moss, snow sand ricks, and many more can be not only become realistic, but at the same time interactive eg footsteps on a beach or snow and much more.
I would like to know
1 what are current limitations, and what the metalness iworkflow limitations, if any, will be too.(explanation with images are welcomed)
2 If there will be limitations or translucency at all( for realistic plants, glass and much more)
3 If You are planning to support double sided materials,(effective for flora)
4 If You plan to support SSS (effective for skin, marbles, pottery, ceramic, fabrics etcetc)
5 if you are planning to support coats in general or in some specific situation
While I can understand that it might be a little time consuming, I would be grateful to have a detailed answer from a Linden Lab interlocutor that is in the Graphics development team. A good answer at this point can be very useful in time for a better quality Sansar platform and help Content creators in the goal of reaching photorealism