This repo provides several glTF Material Converter Packs for CRglTF to convert PBR material from glTF V2 file into custom material format used by shader pack.
Download them at the Latest Releases.
Below are the results of each glTF Material Converter Pack by using CRglTF-Example.
For LabPBR 1.3 Converter Pack, the PBR Metallic to the Green Channel of Specular texture is just a Visually Acceptable conversion. Please using BSL SEUS PBR Converter Pack if you want exact PBR result as in glTF V2 specs.