Gltf-blender-io: Exporter: Use Principled BSDF / Deprecate custom glTF node groups

[UX3D-nopper]

Principled BSDF export

• [x] Scalars and vectors
• [x] Extract channels and merge image functionality
• [x] Images, textures and samplers
  
  
  
  • [x] Normal
  
  
  • [x] Emissive
  
  
  • [x] Base Color
  
  
  • [x] Metallic
  
  
  • [x] Roughness
  
  

[emackey]

/cc https://github.com/KhronosGroup/glTF-Blender-Exporter/issues/101

[UX3D-nopper]

As discussed, having the importer and exporter in one place, this will finally result in a "smooth" round trip import - export.

[Chaoss86]

Roughness does not export, have tried almost eeverything I can think of.

[donmccurdy]

@Chaoss86 see in-progress docs: https://gltf-blender-io-docs-fuznnktuig.now.sh/addons/io_gltf2. If that node structure is not working for you, could you file a new bug with more details?