Fields for this extension?

[m-mohr]

Proposal for now:

• vector:geometry_types (array[string]) - Geometry types present in the dataset. Which types to use? Just GeoJSON gemetry types or the advanced ones from JSON-FG?
• vector:mmu (number; unit: m²) - Minimum Mapping Unit — smallest polygon area represented.
• vector:mmw (number; unit: m) - Minimal Mapping Width — smallest real-world width represented as polygon.
• vector:reference_scale (integer) - Representative fraction denominator (e.g., 50000 for 1:50,000).
• Any other fields required?

The fields are available as usual in Collection, Item, Assets.

The fields should be reusable e.g. in the table extension (see also stac-extensions/table#13)

Feedback would be very welcome

[cboettig]

This is fantastic!

How about vector:layers -- layer names within a vector file

Many vector formats contain named layers, (e.g. MapLibre requires source-layer, some tools will default to the first layer if not provided). doing an ogrinfo call to check layer name first can be very slow (and assumes gdal is installed), vs just checking a STAC catalog. This would be immediately useful to us in our own stac catalog.

Would probably be array because GDB/GPKG could have multiple layers.

[m-mohr]

The vector:layers is interesting, it could even be a bands like array of objects where you can define more than just the name.

It could also be replacing the wmts:layer / wms:layer fields in the web map links extension, not quite vector though.

So maybe layers is not actually a vector-specific concept them?

[m-mohr]

Closing as the first proposal is online: github.com/stac-extensions/vector

Moved the discussion around layers to #2