Include the option to change the geometry smoothing

[Smash-ter]

Current issue with the exporter with Blender 4.2 is how geometry smoothing effects blendshape normals when they are set to "Import" in Unity. In blender the default option in the regular FBX exporter is set to Normals Only. This will result in Blendshapes being exported with sharp edges and split normals in places where they're not supposed to be split in. Below is an example of the problem I'm experiencing.

The solution would be to change the geometry smoothing option from "normals only" to either "Face" or "Edge," which will fix the unintentional sharp geometry and properly recalculates the blendshape normals when set to the "Import" mode in the FBX import setting in Unity. Reference to the fix is below.

[EdyJ]

Could you please upload a .blend file I could use for testing and verification of the fix?

[Smash-ter]

@EdyJ this model has two blendshapes. Only thing you might need to do is slap an armature on it, but when testing the import settings in unity have your import settings set to this

This is causing issues with regards to generating sharp tangents due to the "Normals Only" option from Geometry smoothing. Blender may fix this in the future, but having the geometry smoothing options exposed in the plugin is something that might help with this problem for the time being
Whopper.zip

[Smash-ter]

Could you please upload a .blend file I could use for testing and verification of the fix?

is there any updates related to this?

[lukis101]

The fix has now finally landed into Blender 5.1
To export blendshape normals correctly, just need to add mesh_smooth_type='SMOOTH_GROUP' into the exporter params dictionary
(as documented here)