1. Presented by: Carsten Rönsdorf

2. CityGML overview plus core standard extension

3. http://www.financialpost.com/executive/smart-shift/story.html?id=2146219
Smart cities theme

4. What is CityGML?
CityGML is an open data model and XML-based format for
the storage and exchange of virtual 3D city models. It is an
application schema for the Geography Markup Language
version 3.1.1 (GML3), the extendible international
standard for spatial data exchange issued by the Open
Geospatial Consortium (OGC) and the ISO TC211.

5. CityGML overview
... Covered by Martin Ford’s presentation (through Mark Stileman)

6. Copyright © 2012 Open Geospatial Consortium
Web 3D Service and Web View Service

7. Copyright © 2012 Open Geospatial Consortium
IGG‘s W3DS serves Paris data (from CityGML) to Google Earth

8. Fraunhofer’s X3DOM City Viewer in the Web browser and on mobile device

9. HPI‘s WVS serves Paris city model to a web and mobile client

10. Features of CityGML
 Geospatial information model (ontology) for
urban landscapes based on the ISO 191xx
family
 GML3 representation of 3D geometries, based
on the ISO 19107 model
 Representation of object surface characteristics
(e.g. textures, materials)
 An out of the box data model that should cover
80-90% of your requirements and can easily be
extended

11. Modularisation
...
CityGML Core
OGC GML 3.1.1
Appearance
Generics
Application Domain Extensions (ADE)Building
CityFurniture
CityObjectGroup
LandUse
Relief
Transportation
Vegetation
WaterBody
Tunnel
Bridge
…

12. Modularisation
Very powerful concept to add an a lot:
- attributes
- features
- relationships
- themes
At what point do we need to extend the core
standard?

13. How long does standardisation take?
• Proposal
– 4 weeks in ETSI if in scope of existing work programme, 3 months or
more if not
• Drafting
– Months, years
• Approval
– Depends on standard type but from 8 weeks to 18 months
• Publication
– Depends on publisher but about 4 weeks is normal
• Maintenance
– Depends on publisher but for essential corrections corregenda may
be published at any time, major review generally every 3-5 years
______ _ __ __ _________ __ _Standardisation timeframes (from Scott Cadzow)

14. OGC timeframes
 Standard process 9-18 months
 Fast track process 3 months, only applicable for well
researched and established, not controversial items
 Need to submit RfC
 Prioritisation and scheduling will be evaluated by OGC
 Alignment with other requirement and potential publication
schedule
 30 day public comment process for draft final version
(similar to Committee Draft at ISO)
 60 days IPR review and OGC voting process

15. The big sticky IPR point
 For any outcomes of iSCOPE (or any other project/input) to
be included into the published CityGML standard, the
consortium needs to transfer IPR to OGC.
 OGC will make make CityGML available on a RAND and
royalty free basis
 We might want to think about an MoU between iSCOPE and
OGC to formalise the relationship and allow iSCOPE
members to fully participate in OGC processes

16. CityGML timeframes
 Version 2.0 was published in April 2012
 Potential work on version 3.0 has been discussed in March
 First RfCs have been submitted
 Work on CityGML 3.0 will start at OGC meeting in Exeter
next week
 Move to GML 3.2.1, authoritative UML model and GML
encoding rules
 Rethink some of the core concepts
 Draft spec expected by end of 2013
 Published CityGML 3.0 spec by mid/end of 2014

18. Additional activities in context of extension
• 3DIM registry sub-group: Objective:
To provide useful specification resources to the user
community, complementary to the CityGML specification.
• Set of user guides focussing on explicit target communities,
probably aligned to the 3 iSCOPE use cases (lead by Martin
Ford, CEN)

19. OGC ADE lifecycle/graduation process
1. Link to external resource
2. Schema validated by 3DIM registry-sub group
3. Content reviewed by 3DIM and comments published
4. OGC Discussion paper agreed by TC
5. OGC BP paper agreed by TC
6. OGC standard agreed by TC (CityGML or separate OGC
standard)
7. Deprecated (Don’t create any new data using this ADE
any more!)
Add user experience as additional attribute

21. iSCOPE requirements
• based on D1.2 Data, Metadata and Modelling
Requirements
• use cases Energy and Noise can be dealt with 100% by
ADEs
• Transport is more challenging and requires a deeper look
into core principles and concept of CityGML
• Number of complementary extension activities that sit
outside the actual specification

22. Extensions of core CityGML
 Master UML model based on GML 3.2.1
 CityGML as an Inspire BU data encoding
 Registries (ADE, feature concept, feature catalogue)
Particular concepts
 Storeys, floors and stairs
 Indoor LoDs
 Floorplans
For the Mobility use case examine and discuss multi-graph
concepts such as in Indoor ML in the iSCOPE consortium and
in OGC