Geoscience Reference
In-Depth Information
(La Beaujardiere
2006
). Operable Web Feature Services are extremely rarely
found in practice. This presumable will drastically change in future. Even if
INSPIRE is restricted to the European Union, this development hopefully will
function as a role model also for other regions.
The focus of this chapter was set on the INSPIRE building model. It is the result
of a detailed and extensive analysis of all use cases for buildings. Four profiles of
the building model accommodate for the heterogeneous uses cases and the het-
erogeneous data availability in the member states of the EU. The INSPIRE
building model has largely been influenced by the building model of CityGML:
modeling patterns such as the Building—BuildingPart hierarchy and many attri-
butes such as the YearOfConstruction and the RoofType have been borrowed from
CityGML. The geometry representation of the Core 3D profile has completely
been adopted from CityGML, as well as the geometry and 3D feature types such as
BoundarySurfaces (WallSurfaces, RoofSurfaces, …), BuildingInstallations and
Rooms of the extended 3D profile.
In the groups which develop CityGML, particularly in the 'Special Interest
Group (SIG) 3D'
5
of the initiative 'Spatial Infrastructure Germany' (GDI-DE) and
in the OGC CityGML Standards Working Group, currently there is a discussion to
adapt INSPIRE concepts back to CityGML. Examples are the feature types Oth-
erConstruction and BuildingUnit as well as metadata which enrich the coarse
LoD1 and LoD2 representations (low and high ElevationReferenceValues, Hori-
zonalGeometryReferenceValues, accuracies). In addition to the move from GML
3.1 to GML 3.2, these extensions of CityGML will contribute significantly to the
harmonization between CityGML and INSPIRE.
Although the INSPIRE and the CityGML building models are similar, their
standard encodings are different: The INSPIRE encoding is derived automatically
by rules from the UML diagrams and maps to GML 3.2 (Portele
2007
), whereas
the GML 3.1 schemas (Cox et al.
2003
) of CityGML have been derived manually.
Due to the different encodings, CityGML tools and software can not immediately
be used for INSPIRE buildings data. However, there are a lot of tools with
CityGML support: tools for storing CityGML data such as the open source data-
base 3DCityDB, Bentley Map 3D, ESRI ArcGIS, to mention only a few. Con-
version tools such as the FME (Feature Manipulating Engine) have CityGML
interfaces, and Web Feature Services such as XtraServer/WFS from Interactive
Instruments, Snowflake GoPublisher,ordeegree 3 from lat/lon provide CityGML
data. In order to enable the usage of these tools for INSPIRE building data and to
facilitate the harmonization between CityGML and INSPIRE, an alternative
encoding for this model based on CityGML was developed (Gröger et al.
2013
). It
uses the CityGML concept of Application Domain Extensions (ADE), which adds
the INSPIRE-specific attributes and relations to CityGML buildings and building
parts. These ADEs for the Core 3D and Extended 3D profiles currently are
developed by the Chair of Geoinformation at the Institute for Geodesy and
5
See
www.sig3d.org
