Hi All , This is not critical to my project as I can work around it. Just thought that I could use the sandbox to make some changes to an existing .glb and use that in my project. I only made changes on one material “glass_1” , changed the albedoColor and the roughness. The export was slightly larger than the original by only ~20kb or so , so I didnt care. But now when trying to use in my project , I assign roughness and normal maps at run time… I saw nothing happening.
So I tested importing the .glb created by the sandbox and discovered it had completely removed the UV channel from that material.
I’m going to go on a hunch and say it does this because there are no textures assigned to the material. This of coarse is how i exported the .glb from blender , since that is determined via user selection at runtime. Just thinking the sandbox is perhaps not exporting the channel when no textures are set??
here is the model to test :
https://www.shaderbytes.co.za/babylonjs/bath_doors_standard_collection.glb
here is a pg loading the model for convenience.
https://playground.babylonjs.com/#2A19U8#18
you can test loading a bump map into the material “glass_1” you will see it works fine.
Reload the sandbox , dont add any materials , change the albedocolor and alph or blendmode and export a glb.
Now import that new glb … and try assign any textures to it … you will see it has no more uv channel.
As mentioned I imported it into my DCC and can confirm the channel is completely missing.
Hope its a easy fix , and again not critical to me , just found it while finishing off my project.
btw Im loving your engine and API … 
thanks for making it available open source.
