Purpose: Ensure that empty objects with children are included in the FBX export, preserving the parent-child relationship upon re-import.
Changes:
Handling Empty Objects:
Modified the do_export method to include empty objects in the export process.
Added 'EMPTY' to the ex_object_types set, ensuring that both empty objects and their children are exported together.
Parent-Child Relationship Preservation:
By including empty objects during export, the parent-child hierarchy is maintained when the FBX file is re-imported into Blender or another 3D software.
Material Handling:
Updated the remove_materials method to avoid errors when processing objects without mesh data, such as empty objects.