Hi I have a questiona bout a few parameters in the Lightening material
VTangent : Boolean
Minnaert : Boolean
WardIso : Boolean
https://wiki.jmonkeyengine.org/legacy/doku.php/jme3:advanced:materials_overview
says they have something to do with shading,
but what does they do exactly and how does it affect the endresult?
VTangent I have no idea, something normal related perhaps ?
I think Minnaert and WardIso effect how light is reflected (think shine, we see this as highlights and lit areas on a model). To my knowledge, Minnaert is a darkened Lambert shader I think (?) and can take on fabric like qualities, where as WardIso can have plastic and metallic like qualities - don’t quote me on this though, I tend to be a fountain of missinformation at times 
I’m sure @nehon will step in and tear my reply a new one when he has finished recharging.
Google knows far more than I do, in the past I have found the Blender documenation to be an excellent resource for covering these sort of concepts.
(@Empire_Phoenix I mean no offence by my simplistic answer, I figured it may be helpful info for the less experienced)
Vtangent is used to compute normals from the tangent data…I don’t really know how it can be useful, but Kirill might know better.
Mineart is another algorithm to compute diffuse lighting, i don’t know the details though
Wardiso is another quality algorithm to compute specular lightings. And indeed gives a plastic look.
For a quick idea of what those parameters implies on a material you can open the sceneviewer and the material editor side by side in jmp and play with the parameters. The updates will be made live in the scene.
Standard
Mineart
http://i.imgur.com/ZN7Im.jpg
Wardiso
http://i.imgur.com/ICIy4.jpg
Vtangents
http://i.imgur.com/223kP.jpg
2 Likes
As far as i understand. VTangent is for specular.
Something like that: http://www.blender.org/development/release-logs/blender-242/material-features/ (Tangent Shading)
Those options do almost the same thing that they do in Blender, so see the Blender docs for explanation