Author Topic: GLB/glTF Export Problem - Exported Metalness Value is Always 1 instead of 0...  (Read 121 times)

Hey everyone, 

I've recently started using Substance Painter to export GLB's - "Export Textures"/"Gltf PBR Metal Roughness" and then I use glb-packer.glitch.me to compact the files exported from Substance Painter (and convert PNG's to jpg) to a single GLB with textures embedded.

The issue I've found - and I have not found a way to correct this - is that Substance Painter only ever seems to export the model with metalness set to 1 (where I'd like it to be set to 0). This is on the GLB both before and after running it through the glb-packer so I know it's not the glb packer that's doing this.

It's causing all sorts of problems on all of the online gltf/glb viewers (three js type). Is there any way to correct this? I'm hoping that I do not have to add another map, as I'm trying to keep these files as small as possible. There must be some way to tell the gltf/glb to export with a metalness value of 0 right? Or maybe it's leaving that value blank and Three JS is defaulting to a value of 1? I'm not sure. Either way, I just need to find out how to fix this.

It could absolutely be that I'm also just doing something wrong. I am fairly new to Substance - though I'm very familiar with many other 3D and 2D programs so I'm quickly understanding the fundamentals. Maybe I'm just missing something here. Have already searched google for (literally) weeks and have not found an answer to this. Could be that I'm just not searching the correct terms. Also asked a friend who's a professional at Substance Painter but he couldn't figure it out either and thinks it could actually be a bug.

Any help would be greatly appreciated - as if I can't find a solution to this problem, I can't use Substance Painter for my projects... at least not to export GLB's.
Last Edit: March 04, 2021, 10:33:01 pm

Anyone else experiencing this?