Support for Flatgeobuf

[tsmcgrath]

Hi, I'd like to see Cesium support for the flatgeobuf format. It's an excellent, compressed, and spatially indexed alternative for geojson vector data.
https://flatgeobuf.org/

[ggetz]

Thanks for the request @tsmcgrath!

Do you have any descriptions of typical use cases or sample data it'd be possible to leave here as a reference if we chose to support?

[tsmcgrath]

Sure. Sorry I didn't add it. Any large geojson files will have performance issues. You can vastly improve performance using flatgeobuf which has spatial indexing built in. So you only request what's in view. Like COGS for raster data. In my case it is for a greater than 14,000 mile national trail geometry that I would love to display on Cesium 3D. I am currently putting them up on Leaflet. Here's an example:
https://flatgeobuf.org/examples/leaflet/