No Metallic Map from Individual Asset Exports?

[haoliu-meta]

I noticed that none of the individual asset exports contain metallic map, even though the code seems to intend to support it. Curious if it's a known issue or by design?

Steps to Reproduce

If this relates to running the codebase, please provide steps to reproduce:
python -m infinigen_examples.generate_individual_assets --output_folder ~/infinigen_outputs/ -f PotFactory -n 2 --render image --export fbx --save_blend --skip_existing

What version of the code were you using?

Tell us the commit & commit hash from git log
v1.5.1: c537e24

What command did you run?

python -m infinigen_examples.generate_individual_assets --output_folder ~/infinigen_outputs/ -f PotFactory -n 2 --render image --export fbx --save_blend --skip_existing

What are your FULL output logs?

Provide the FULL output logs from your command as a txt file.
infinigen-240729.txt

Additional context

It seems the metal pass is always skipped due to the lack of a principled BSDF

[lez-s]

did you solve the problem? I am also trying to extract metallic map, but couldn't find a way to do it.
python -m infinigen_examples.generate_nature --seed 0 --task render --input_folder outputs/indoors/coarse --output_folder outputs/indoors/frames
@David-Yan1 @haoliu-meta @araistrick