-
Notifications
You must be signed in to change notification settings - Fork 8
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
DGGS RSID elaboration and implementation issues #41
Comments
My main confusion is currently accessing data vs only zone/dggs definitions: /collection/(collectionid)/dggs/(dggsrsid)/zones: then you could separate the DGGS index and the data layers? or you would assume all data indexed under a DGGS on a server needs to be accessible via: /dggs/(dggsrsid)/zones ? |
Some ideas below:
@jerstlouis I think you encountered a similar question to #41 (comment) in either OGC API - Tiles or OGC API - Coverages. How did you address it there? |
We cannot have both @rggibb @geofizzydrink @pvretano For a DGGS: What is here? conformance class, I think we would want to return data (e.g. as GeoJSON or FlatGeoBuf for vector features, and for raster GeoTIFF or a more compact format that encodes the particular shape of the e.g. hexagonal shape of the tile) at:
and for the DGGS: Where is this? conformance class, I think we want to return a list of zones at:
which can take additional parameters like To me these are the basic practical and useful conformance classes for OGC API - DGGS. Then the next most useful one would be DGGS: CQL2 support (used with e.g.
|
OGC Abstract Specification Topic 21 v2.0 Figure 13 has some elements that need further elaboration and dsiscussion before they can be implemented.
The OGC API DGGS refers to an identifier that resolves to a full specification of a DGGS RS
/dggs/{dggsRSID}
.At present the DGGS RS that are in use have been given informal identifers, for example H3, AusPIX and TB16-Pix and each of these are described by association with the library that is currently used to create them - which is sufficient for current purposes but isnt robust enough or transparent enough to cater for the range of possibilities that we expect to arise once people start to use the AS Topc 21 more widely. Figure 13 includes a structure that caters to that future, and the development of OGC API DGGS is an appropriate trigger to start doing things more robustly. Part of that is creation of the DGGS Registry cf Issue 36. This issue is intended to start conversations around other elements that may or may not yet be formally supported by existing infrastructures.
A DGGS RS brings together a number of component parts that could exist on their own and therefore can be described independently. This is analogous to the situation with projections, where the defintion of the ellipsoid used to describe the Earth is defined seperately from the definition of the sets of axes. A particular projection is then the combination of a definition of an ellispoid and a definition - including orgin and orientation of a coordinate set.
For DGGS the component parts are - with reference to the elemnts highlighted in red below, which is Figure 13:
4.1. (cf DGG_ReferenceSystem::DGGS_Grids) The list of 1..* DGG_GridContraint(s)
4.2. (cf DGG_ReferenceSystem::DGGS_Refinement) The list of 1..* DGG_RefinementStrategy(s)
4.3. (cf DGG_ReferenceSystem::DGGS_RefinementRatio) The sequence of 1..* RefinementRatios
The text was updated successfully, but these errors were encountered: