Collection of use cases that should be supported

[SharkWipf]

We should probably try to have a clear understanding of the kinds of use cases we're trying to support.

At the most fundamental level, it boils down to "we should be able to encapsulate any current and future gaussian splatting (and implicitly NeRF) file format and add useful metadata to it".

In practice, wrapping formats like .ply, glTF, .spz, etc is pretty straightforward since we don't do anything to the file except packaging it.
But in order to avoid any surprises, we should gather an explicit list of use cases/standards we wish to support.

Some quick ones off the top of my head:

• Inria/3dgs/nerfstudio basic .ply
• Plain compressed .ply files
• .png compressed gaussian splatting scenes
• .spz compressed format
• ScaffoldGS
• 4dgs/gaussian videos/animations

Please post any use cases you can think of where this format may be of interest. The goal is to get an as complete as possible list of projects/formats so we can sanity check the spec and avoid unfortunate surprises.