Schema - Group of Lakes

[harahu]

@dieterdreist

one is creating a central point with the name, size and type (e.g. water related, natural feature related, peak related, place related etc.), where the type ultimately depends on the targeted map style/distinctions you want to make.

Of the two solutions I prefer this one, since it treats the group(s) as distinct objects.

@dieterdreist

this is up to the data consumer how fault tolerant they want to be.

Keep in mind that data consumers are also other mappers. When I talk about validation I was initially talking about the potential for generating warnings in tools like iD and JOSM. But I realize this is relevant for renderers as well.

@dieterdreist

Generally, it is possible to add specific tags to group relations, it just isn’t required. Do you suggest to invent specific tags for every kind of group imaginable, e.g. group of lakes, group of peaks, group of trees, group of rocks, group of farms, group of sculptures, group of ponds, group of springs, group of villages, group of islands (this one has already a specific tag), …

To me it seems preferable to do so. Perhaps it isn’t technically required, but, as a data consumer I would be less hesitant to render a grouping that is explicit about its purpose. I would probably propose such a tag for lake groupings as part of the proposal.

@dieterdreist

I think requiring the group members to be „of the same kind“ (tagging wise, not regarding the geometry type) is an essential requirement, otherwise it is a site or something else.

I agree with you here, but I also think this gets challenging without explicitness about group type. For instance, a pond and a lake can be viewed as “of the same kind”, but also not, depending on whether you are grouping water areas or something more narrow. I suspect variations of this problem will show up a lot.