In the materials properties of your object, you can assign materials based on faces selected in edit mode. Assign your faces to dumby materials (diffuse node setups in cycles). When ready to export, create the number of dumby materials you have as PDX materials (left side in the pdx tools menu), name them so you remember and write it down.
Later, in your gfx code, you can use meshsetting = {} blocks to assign each shader a diffuse texture, a normal texture, and a specular texture.
If you are looking to use different UV layouts as well, just make sure to have your UV's set up properly, in one uv set. I'm not sure if you can "merge" uv sets in blender, but from my testing i can't figure out how to export multiple uv sets. This also means you can't have diffuse-specific uv layouts!
https://docs.google.com/document/d/...SH6yMTymA8B0jpTog/edit#heading=h.kmyblpvdg80d
You can find the relevant section in my guide here.
Just to recap:
Assign sections of your mesh to different material slots
Assign PDX Shaders created with the tool to those material slots
Use meshsettings = {} blocks to call each shader (that you made earlier) and assign your textures
Later, in your gfx code, you can use meshsetting = {} blocks to assign each shader a diffuse texture, a normal texture, and a specular texture.
If you are looking to use different UV layouts as well, just make sure to have your UV's set up properly, in one uv set. I'm not sure if you can "merge" uv sets in blender, but from my testing i can't figure out how to export multiple uv sets. This also means you can't have diffuse-specific uv layouts!
https://docs.google.com/document/d/...SH6yMTymA8B0jpTog/edit#heading=h.kmyblpvdg80d
You can find the relevant section in my guide here.
Just to recap:
Assign sections of your mesh to different material slots
Assign PDX Shaders created with the tool to those material slots
Use meshsettings = {} blocks to call each shader (that you made earlier) and assign your textures