An XVIZ version of PNG and GIF

[jlisee]

Lets get the discussion started.

[twojtasz]

Why not have an index? Or maybe add an "index" to the metadata field.

With JSON, it probably doesn't matter as much, but with GLB an index could help a lot. It depends on how this takes shape in GLB, if we split each frame to a separate BIN chunk and add additional JSON chunks for each frame.

After asking that question, it seems that GLB optimal streaming is more complicated than we likely need. And I recall reading that a "streaming" GLB proposal was treating individual frames as GLB and had an external index so I think i'm asking questions on a different problem ;)

[CLAassistant]

All committers have signed the CLA.