Use pbrMetallicRoughness instead of KHR_materials_pbrSpecularGlossiness

[electrowolff]

Can the exporter use the standard pbrMetallicRoughness rather than the extension?

https://github.com/KhronosGroup/glTF/tree/master/specification/2.0#reference-pbrmetallicroughness

[AurL]

Hi @electrowolff,

The exporter doesn't perform conversion between PBR workflows (metallicRoughness / specularGlossiness), as it would require much more image processing, tasks that we want to avoid as much as possible to avoid having crazy processing timings during the export.

Don't hesitate to ping back if I misunderstood your question