Scene Metadata
The scene class should support metadata. Adding metadata support in dirfm will make it possible to have unique metadata for a given scene. Scene metadata needs to be written to the dataset metadata on Rendered.ai, dirfm could be used to provide it.
The content for a scene has some timestamp, either a release date, or at least the date of most recent updates (e.g. to ems data, atmospheric models, or parameters used by material models). Also, the scene description, and an author when appropriate. Currently, these are independently tracked in existing DIRSIG scene content and in channel code.