handle site relations

[tyrasd]

-> maybe render as GeometryCollection features.

related: https://github.com/tyrasd/overpass-turbo/issues/293, #42, #58

[planemad]

@tyrasd here is an example of a turn restriction relation represented as a GeometryCollection:

https://gist.github.com/anonymous/101194662ce0ab4bf19ce8e319fdbfd1

It looks like we could represent any relation this way perfectly as a valid geojson.

[tyrasd]

Yeah… But the question is if the respective OSM relations actually do represent some "geometric" feature on their own or not. For example in the case of this turn restriction: On the one hand yes, this GeometryCollection shows the OSM objects that were used to map the turn restriction, but on the other hand the turn restriction in itself is only an abstract concept about the relationship between two ways, and thus are more like properties of the two ways and one node.

Btw: Adding properties to a geometry (like here) is not actually valid GeoJSON. But I guess one could simply have the roles information stored in an array of the outer feature's properties object.

[planemad]

But the question is if the respective OSM relations actually do represent some "geometric" feature on their own or not.

Its not always going to make sense, but having each relation as an independent geojson feature opens up a lot of applications from using various libraries for spatial analysis or for interactivity on a map.

But I guess one could simply have the roles information stored in an array of the outer feature's properties object.

Have tried this out in this updated example

[tyrasd]

having each relation as an independent geojson feature opens up a lot of applications

that's a good point