ACTION-98: Look at a list/matrix of the common formats (geojson, gml, rdf, json-ld) and what you can or can't achieve with it

Dear all,

below is a first attempt at such a matrix for vector data only.

Beside a review (I am not sure that everything is correct or adequate) this
would need
- additional explanations in text,
- more work to align the terminology with the rest of the BP to make it
understandable for the different target audiences,
- links to the specification for each format.

But before we work on this, I think we should have a discussion whether
- this is what we were looking for in general,
- the list of aspects is complete, too much, or missing important aspects
(e.g. time support, closely coupled APIs / service interfaces, etc),
- the list of formats is ok or whether we need to remove / add some.

I hope the table is still readable once it passes the W3C list software :)

     GML GML-SF0  JSON-LD GeoSPARQL (vocabulary) Schema.org GeoJSON KML
GeoPackage Shapefile GeoServices / Esri JSON Mapbox Vector Tiles Governing
Body OGC, ISO OGC W3C OGC Google, Microsoft, Yahoo, Yandex Authors (now in
IETF process) OGC OGC Esri Esri Mapbox Based on XML GML JSON RDF HTML with
RDFa, Microdata, JSON-LD JSON XML SQLite, SF SQL dBASE JSON Google protocol
buffers Requires authoring of a vocabulary/schema for my data (or use of
existing ones) Yes (using XML Schema) Yes (using XML Schema) Yes (using
@context) Yes (using RDF schema) No, schema.org specifies a vocabulary that
should be used No No Implicitly (SQLite tables) Implicitly (dBASE table) No
No Supports reuse of third party vocabularies for features and properties
Yes Yes Yes Yes Yes No No No No No No Supports extensions (geometry types,
metadata, etc.) Yes No Yes Yes Yes No (under discussion in IETF) Yes
(rarely used except by Google) Yes No No No Supports non-simple property
values Yes No Yes Yes Yes Yes (in practice: not used) No No No No No Supports
multiple values per property Yes No Yes Yes Yes Yes (in practice: not used)
No No No No No Supports multiple geometries per feature Yes Yes n/a Yes Yes
(but probably not in practice?) No Yes No No No No Support for Coordinate
Reference Systems any any n/a many WGS84 latitude, longitude WGS84
longitude, latitude with optional elevation WGS84 longitude, latitude with
optional elevation many many many WGS84 spherical mercator projection Support
for non-linear interpolations in curves Yes Yes (only arcs) n/a Yes (using
GML) No No No Yes, in an extension No No No Support for non-planar
interpolations in surfaces Yes No n/a Yes (using GML) No No No No No
No No Support
for solids (3D) Yes Yes n/a Yes (using GML) No No No No No No No Feature in
a feature collection has URI (required for ★★★★) Yes, via XML ID Yes, via
XML ID Yes, via @id keyword Yes Yes, via HTML ID No Yes, via XML ID No No No
No Support for hyperlinks (required for ★★★★★) Yes Yes Yes Yes Yes No No No
No No No Media type application/gml+xml application/gml+xml with profile
parameter application/ld+json application/rdf+xml, application/ld+json, etc.
text/html application/vnd.geo+json application/vnd.google-earth.kml+xml,
application/vnd.google-earth.kmz - - - - Remarks comprehensive and
supporting many use cases, but requires strong XML skills simplified
profile of GML no support for spatial data, a GeoJSON-LD is under
discussion GeoSPARQL
also specifies related extension functions for SPARQL;
other geospatial vocabularies exist, see ??? schema.org markup is indexed
by major search engines supported by many mapping APIs focussed on
visualisation of and interaction with spatial data, typically in Earth
browsers liek Google Earth used to support "native" access to geospatial
data across all enterprise and personal computing environments, including
mobile devices supported by
almost all GIS mainly used via the GeoServices REST API used for sharing
geospatial data in tiles, mainly for display in maps
Best regards,
Clemens