Specify interpretation of UsedArea for RoadNetwork
Describe the feature
In the RoadNetwork element the UsedArea of the map is specified as a list of Position, but there is no specification how this list shall be interpreted. There are two main use-cases "Highway" and "Urban" where different interpretations make sense.
For highway scenarios an interpretation of the points as route makes sense, for urban scenarios an interpretation as polygon makes sense.
Describe the solution you would like
An additional enum attribute in the UsedArea element called areaShape with the values route and polygon, whereas polygon is the default. If the value is polygon and there are only two positions provided, then the shape is interpreted as rectangle.
Describe alternatives you have considered
Adding information in unstandardized way to file header as property.
Describe the backwards compatibility
Since the interpretation of the area was not specified before, the change is backward compatible. We'd propose to use polygon as default value to comply with the more intuitive interpretation.