Add IOR as face attribute

[CodeFHD]

(Suggest in a YouTube-comment)

Add the index of refraction (or corresponding ratio) as an attribute to each face for automatic application and avoiding definition of multiple glass materials.

Checklist:

• Read up on API
  • Blender
  • Cycles
  • LuxCore
• Verify that all aspects would be treated appropriately
  • Dispersion
  • Fresnel reflection
• Write assignment code
• Write automatic material assignment
• Write connection to material