3.0.0-draft.2019.04.09.1

This is a new release of the draft OGC CityGML 3.0 Conceptual Model.

Notable changes and additions

• The classes Void and VoidSurface and the underlying concept of substractive elements were removed from the Core module without substitution. As a consequence, the class AbstractSpaceBoundary was replaced by its former subclass AbstractThematicSurface. Both changes result in a substantial simplification of the Core module. #22
• The abstract class AbstractFillingSurface was added to the Construction module as a new subclass of AbstractThematicSurface to semantically distinguish between construction surfaces like wall and roof surfaces and surfaces filling their openings such as door and window surfaces. #54
  • The type AbstractFillingSurface therefore corresponds to the class _Opening in CityGML 2.0. But in contrast to _Opening, the semantics are clearer and the spatial representation must be surface-based (not volumetric).
• Likewise, a new abstract class AbstractFillingElement was added to the Construction module to model the volumetric fillings of openings in volumetric constructive elements.
• The attributes volume and area were added to the class AbstractSpace, the attribute area was added to the class AbstractThematicSurface. In addition, the data types QualifiedVolume and QualifiedArea as well as the code lists QualifiedVolumeValue and QualifiedAreaValue were defined. #51
• The attribute dateOfRenovation was removed from AbstractConstruction an replaced by a more generic attribute called constructionEvent that can be used to represent various and different date-based events including the date of renovation. The event types are provided in the extensible code list EventValue. #53

See the change log for the complete list of changes. The changes to the UML model are also documented in this PDF document.

GML application schemas and test datasets for this release of the Conceptual Model are available from the releases section of the CityGML-3.0Encodings repository. Please make sure to download the matching release.

The free an open-source tool citygml2-to-citygml3 allows for easily and automatically converting existing CityGML 2.0 datasets to CityGML 3.0. The version v0.4.0 of the tool already implements all changes proposed in this draft release.