Unlike a geometry type, a semantic surface type HAS an extension escape
hatch -- CityJSON section 3.3 says "it is possible to define and use other
semantics, but these have to start with a +" -- so a tag with no name of
its own still has a schema-valid spelling available and this emits one
rather than throwing. "+GenericSurface" and not "ExtraSemanticSurface":
the latter is the FlatBuffers enumerator name, is not a CityJSON surface
type and carries no +, so a document containing it fails validation.
UNKNOWN-TAG POLICY, the semantic-surface site.
Unlike a geometry type, a semantic surface type HAS an extension escape hatch -- CityJSON section 3.3 says "it is possible to define and use other semantics, but these have to start with a
+" -- so a tag with no name of its own still has a schema-valid spelling available and this emits one rather than throwing."+GenericSurface"and not"ExtraSemanticSurface": the latter is the FlatBuffers enumerator name, is not a CityJSON surface type and carries no+, so a document containing it fails validation.