The pbr shader nor working for metallic

Hi all,

I am in chapeter 7, the part which is using pbr render function from Apple’s LODwithFunctionSpecialization. It renders fine with the chest example, however, when I tried to load a model with actual metallic texture, it appears all white for the metal part, no matter what viewing angle. Is there a bug in the shader?

@david402 - I’ve been working on this recently. This is the new PBR shader I came up with:

Let me know what you think.

Metallics are always a bit unsatisfactory without reflection.

@caroline Unfortunately I think it does look more like metal now. I tried to write my own pbr shader based on https://learnopengl.com/PBR/Lighting, and I think it works as well. The Fresnel setting is very important for metallic material it seems.
This is the rendering result from your new shader.
Screen Shot 2022-03-27 at 3.58.50 PM
This is my rendering with the implementation from the link above.
Screen Shot 2022-03-27 at 3.55.16 PM

I think I messed up something in my renderer, it could not load the metallic texture properly, therefore I hardcoded metallic value to 1 in my shader.
Here is my pbr shader file.

Thank you for replying.