Short description of the CityGML standard
CityGML is an international standard for the interoperable representation and exchange of virtual 3D city and landscape models. CityGML defines a conceptual schema for the most relevant entities of the urban space like buildings, roads, railways, tunnels, bridges, city furniture, water bodies, vegetation, and the terrain. The conceptual schema specifies how and into which parts and pieces physical objects of the real world should be decomposed and classified. All objects can be represented with respect to their semantics, 3D geometry, 3D topology, and appearances in five predefined levels of detail (LOD 0-4). CityGML is formally specified using UML class diagrams, a feature catalogue with definitions and explanations of the object classes and attributes, and an XML schema for the file exchange format. CityGML is issued by the Open Geospatial Consortium (OGC). The current release is version 2.0.0.
The Role of CityGML in SDDI
- general description of the purpose and usage of CityGML in SDDI
Currently, the 3D virtual district models of the SSD districts London QEOP, Paris Docks de St. Ouen, Berlin, Moabit west, Utrecht, The New Centre, and Helsinki are modeled and encoded according to the CityGML standard.
Standard Specification
Specification documents: http://www.opengeospatial.org/standards/citygml
CityGML Homepage: https://www.citygml.org/
Implementations / Products
The following selection of products was made by the SDDI team and includes those implementations which are (or likely will be) used in the SSD project and from which we know that they are compatible with the requirements of the Smart Sustainable Data Infrastructure. Please note that the list is not a complete list of available or suitable CityGML implementations.
CityGML implementations (GIS, spatial database management systems, libraries, tools):
| Name | Type | License | Homepage | Short description | Used in components |
|---|---|---|---|---|---|
| 3DCityDB | Geodatabase | Open Source | http://www.3dcitydb.org/ | Runs with the Spatial DBMS Oracle Spatial (commercial) and PostgreSQL / PostGIS (Open Source). | |
| 3DCityDB Webclient | Viewer | Open Source | https://github.com/3dcitydb/3dcitydb-web-map | The 3DCityDB Webclient is based on the Open Source 3D Digital Globe viewer Cesium [https://cesiumjs.org/]. Runs on any modern web browser (Chrome, Firefox, Safari) on most platforms (Windows, Linux, Mac OS, Android, iOS) including mobile devices. | |
| FZK Viewer | Viewer | free software | http://iai-typo3.iai.fzk.de/www-extern/index.php?id=1931&L=1 | Runs on Windows platforms. | |
| Azul | Viewer | Open Source | https://github.com/tudelft3d/azul | Runs on Mac OS 10.12 platforms. | |
virtualcityDATABASE | Geodatabase | commercial | http://www.virtualcitysystems.de/en/products/virtualcitydatabase | ||
virtualcityWAREHOUSE | Data Platform | commercial | http://www.virtualcitysystems.de/en/products/virtualcitywarehouse | ||
virtualcityPUBLISHER | Viewer | commercial | http://www.virtualcitysystems.de/en/products/virtualcitypublisher | The virtualcityPUBLISHER is a solution for creating and publishing interactive 3D mapping applications from CityGML-based 3D geodata. With few steps, 3D geodata can be presented in the Internet and combined with existing 2D geodata services. virtualcityPUBLISHER is based on the Open Source 3D Digital Globe viewer Cesium [https://cesiumjs.org/]. | |
BuildingReconstruction | 3D Data Acquisition Tool / Editor | commercial | http://www.virtualcitysystems.de/en/products/buildingreconstruction | BuildingReconstruction is a software for the automatic extraction of 3D building models from digital surface models and 2D building footprints. It has been and is being used e.g. to generate and update the CityGML LOD2 building models of the 3D city models of Berlin, Helsinki, Frankfurt etc. In the SSD project it was used to generate the Virtual District Models of Paris, Docks de St. Ouen, London QEOP, and Berlin Moabit West. | |
| CityEditor | Editor / 3D Data Acquisition Tool | commercial | https://www.3dis.de/loesungen/3d-stadtmodelle/cityeditor/produktinformationen/ | Sketchup Plugin | |
| citygml4j | Library | Open Source | https://github.com/citygml4j | Programming library for Java. API for reading, writing, and manipulation of CityGML datasets. | 3DCityDB, virtualcityDATABASE |
| Feature Manipulation Engine (FME) | ETL Tool / Viewer | commercial | https://www.safe.com/ | ESRI ArcGIS Interoperability Extension |
Additional Information
to be provided