[Tagging] V3 to V4 Mapillary image id migration

[Kai Michael Poppe - OSM]

@CJ,

Thanks for clearing that up for me, I'll guess for the "cleanup" of the no-longer-existing-old-valid-values I'll have to put two Challenges, one with Nodes/Ways and one with any one member of a Relation and a different description - as MapRoulette only has GeoJSON or an overpass query which might not be useful in this case (have to check).

@Peter,

Thanks for clearing the whole Challenge!

Kai

On 03.11.2021 16:29, Cj Malone wrote:
> On Wed, 2021-11-03 at 14:01 +0100, osm at poppe.dev wrote:
>> Q1 - yes. If there's a way/node in the Challenge that has no
>> mapillary=* tagging then it is most likely part of a relation where
>> that's the case. When setting up the challenge, I was 99% sure I
>> added the Relations as their own objects and put them into the
>> GeoJSON that's the basis for the Challenge. It might very well be
>> that MR just ignores relations (as it might not know how to display
>> them properly) and add the objects that are part of it (as they are
>> in the GeoJSON as well) or I was just too stupid to deliver the
>> correct data.
> GeoJSON doesn't support relations. It's kinda a bad format for complex
> data structures, like anything that comes from OSM.
>
> Another one is, if a way has a node in it with a tag on it, it's
> actually stored as a point in the way, and separately a node on it's
> own (with the tags) then the program that reads the data has to
> correlate the points with nodes by finding anything that shares a
> location. This then means if you have 2 nodes with the same location
> they can erroneously get merged into one point with some software (like
> JOSM).
>
> I used to love geojson before running into weird issues like this. Now
> I try to keep things in .osm as much as possible.
>
> Cj
>
>