Material disappears when using Inventory to change a model version

[alainxi]

Is there an existing issue for this?

• I have searched the existing issues and added correct labels.

Description

In Blender we use Ayon-->Load to get the geometry (for example version v003 of a .blend file).
Then we attach some material to that object.

Later, if we use the Scene Inventory (Ayon-->Manage) to change the geometry version (for example v004), the material and all its nodes disappear.

And if, instead of a .blend file, I try to load a .fbx file (also from Ayon's Inventory), the problem is slightly different (some material included in the fbx appears, instead of the material that we attached in Blender after having loading it).

In both cases ( .blend and .fbx ), the material that is attached to a loaded object, does not survive if we change the version of that object.

Steps To Reproduce:

Described above.

Additional context:

Came up on Discord here :
https://discord.com/channels/517362899170230292/563751989075378201/1359522701273727279

Relevant log output:

[BigRoy]

This has come up before, including a nice screen recording showing the issue of losing overrides. Here: https://discord.com/channels/517362899170230292/563751989075378201/1347986713292574886

Using a link loader could solve this. For which this PR is a draft: #105

[MustafaJafar]

What about extending the loaders to preserve these links when updating model and shading?

I think blender removes the whole object and create new one when loading, so we may save the metadata/properties of the current object/container and then apply them back?

[LiborBatek]

I guess the issue been blender does not have any sort of reference edits but only on linked libraries as @BigRoy mentioned already so afaik there is no simple way of retaining such local overrides when using classic append load (similar to import in maya terms)

[moonyuet]

The class append function would remove the asset and reload the latest one. We can try to see if we can update by comparing the datablock of the current blend with that of the previous blend. But for most of the cases, it would be safer to use blend linker for changing versions as users can change the assets based on the linked blend file. T

[BigRoy]

I guess the issue been blender does not have any sort of reference edits but only on linked libraries as @BigRoy mentioned already so afaik there is no simple way of retaining such local overrides when using classic append load (similar to import in maya terms)

The best use case here is perhaps:

• Link Loader
• Alembic datablock loader

Both should not be suffering from this due to how they work?