Modular Importers API and custom asset metadata

In Unity roadmap in Pipeline & Integrations section there is Modular Importer entry, that is currently In Progress.

I would like to know more info from Unity about this update:

  • When it will be released?
  • How exactly will this api function?
  • Is it allows to add some kind of “Importer Modules” for any importer type in the project?
  • Can you add thees modules to built-in importers?
  • Can custom metadata be defined? In ScriptedImporter all serialized fields will be saved to *.meta file of an asset, can you add cusom metadata to any asset importer with this API?
  • How will built-in importer Editors support modules? Because right now with AssetPostprocessor’s in importer edtior you can see which post-processors and which of their methods affects this asset, but they can’t contribute to editor OnInspectorGUI() method. (Can’t have custom GUI for settings/metadata)

I mostly interesed in cusom metadata, and current solution is AssetImporter.userData field, however it might get used by differenet assets diferently, and you can’t guarantee safety of this data.

  • Before Modular Importers release, is there any better aproaches then AssetImporter.userData?
  • Is it possible to write directly to *.meta file to append some data at file end, and then read it or will it cause IO conflicts with AssetDatabase or break serialization?
    There seems to be AssetDatabase.ReleaseCachedFileHandles() function that allows to safely edit *.meta files.