cityjson / specs

Specifications for CityJSON, a JSON-based encoding for 3D city models
https://cityjson.org
Creative Commons Zero v1.0 Universal
109 stars 25 forks source link

Transportation additions #73

Closed liberostelios closed 3 years ago

liberostelios commented 3 years ago

This is to add CityGML v3 elements into the transportation module.

For the direction of traffic we assume that in case of one-way roads the orientation is implied by the orientation of the geometries vertices. This is because the original proposal's values (forwards/backwards) makes little sense when using a MultiLineString as the creator of the geometry will already have to make use that all individual linestrings are of the same orientation. Therefore, having to specify an orientation on top of that, seems unnecessary.

Special thanks to @Athelena for making the CityGML v3 changes happen.

hugoledoux commented 3 years ago

For the direction of traffic we assume that in case of one-way roads the orientation is implied by the orientation of the geometries vertices.

Hold on, this works only for LineString, what if the road is a surface?

liberostelios commented 3 years ago

That's a good point. Then the attribute doesn't make sense. But this is pretty much how CityGML v3 does it (an object-level attribute). Since the attribute isn't mandatory, I guess it's okay

Athelena commented 3 years ago

A great point indeed. We can make it clear that it's for linear representation?