4th of March, 2008
Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML - Modelling our environment
Alexandra Stadler, Thomas H. Kolbe
Technische Universität BerlinInstitute for Geodesy and Geoinformation ScienceChair of Methods of Geoinformation Science
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Ongoing virtualisationof our environment
Semantic models of all relevant objects in urban space
Base models include most important feature classes and attributes
Objects may have several geometrical representations
Spatial reference links data of different disciplines, since they refer to the same physical space
Initiatives Inspire EuroSDR
MotivationMotivation
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Standards are the key…Standards are the key…
…to the integration of (3d geo) data of different data sources
Application
Data source A Data source B
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Never heard about CityGML – what‘s that?Never heard about CityGML – what‘s that?
Content Modelling of all relevant parts of the virtual city according to
theirsemantics, geometry, topology and appearance
GML 3 application schema (XML based) Data model and exchange format for virtual 3d city models
History Developed since 2002 by the Special Interest Group 3d
(NorthRhine Westphalia, Germany) Members from >70 companies, municiplaities and research
institutions
lead managed by Prof. Thomas Kolbe (IGG TU Berlin)
Dr. Gerhard Gröger (IGG Uni Bonn)
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML‘s way to become an OGC standardCityGML‘s way to become an OGC standard
CityGML 0.4.0OGC Best Practices Paper
CityGML 1.0.0 (Proposal)OGC Request for Comments
CityGML 0.3.0OGC Discussion Paper
2007-05-30
2008-02-04
2006-03-06
2008-02-192008-03-20
CityGML 1.0.0OGC Implementation Specification(after final OGC TC vote)
coming soon
<<<<<<< Public Comment Phase >>>>>>>
International Standard
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ModularisationModularisation
CityGML consists of the core module several extension modules vertical
subdivision
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Coherence of semantics and geometryCoherence of semantics and geometry
…
Semantic objecte.g. Building
Corresponding geometrye.g. Solid
…
Use of Boundary Representation (B-Rep) for geometry modelling
Explicit relations between semantic objects and their geometrical representations
* *
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
GeometrySemantics
KML: No semantics, only (unstructured) geometry
CityGML vs. KMLCityGML vs. KML
CityGML: (Up to) Complex objects with structured geometrySemantics Geometr
y
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
„Availability“ of semantics„Availability“ of semantics
Geometric entities know WHAT they are Semantic entities know WHERE they are and what their
spatial extents are
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Multi-scale modellingMulti-scale modelling
LOD 4 – Interior model„Walkable“ architectural models
LOD 3 – City / Site modelDetailed architectural model
LOD 2 – City / Site modelExplicit roof structures
LOD 1 – City / Site model„Block model“ without roof structures
LOD 0 – Regional model2.5d Digital Terrain Model
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Terrain intersection curveTerrain intersection curve
Defines the intersection of an object with the terrain Applicable to
Building CityFurniture GenericCityObject Implicitly: WaterBody, Transportation, LandUse
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
External referencesExternal references
Objects may Refer to their original data sources Refer to other external data sources containing additional
data, e.g. Building: Link to cadastre, information about owners Door: Link to facility management systems Antenna: Link to mobile communication databases
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
AppearancesAppearances
Materials (similar to X3D) Textures
Standard textures (explicit texture coordinates)
Aerial images (georeferenced)
Projected photos
Multiple appearances (themes) per object
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Application Domain Extensions (ADE)Application Domain Extensions (ADE)
= Specific application schemata (e.g., noise immission mapping)
Extend CityGML model by Additional feature classes Additional attributes Additional relations
Design remarks: CityGML+ADE files remain valid CityGML „Pure“ CityGML readers ignore ADE
(unknown namespace!) Accessible XSD document required for each ADE
Used for validating corresponding CityGML files
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
German cities modelled in CityGMLGerman cities modelled in CityGML
3d city models based on CityGML Berlin Dresden Stuttgart Bonn Cologne Frankfurt/Main … whole NRW in LOD 1
Planned for Karlsruhe …
Berlin (GoogleEarth)
Stuttgart (SupportGIS)
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ImplementationImplementation
Growing awareness of CityGML (particularily in the US)
Discussions with Web 3D Consortium CTO GoogleEarth International Alliance for Interoperability (IFC-Standard)
Selected implementations: Oracle 11G Spatial Bentley Microstation, Onuma Planning System (CAAD) Feature Manipulation Engine (FME) Snowflake Software, lat/lon (Web Feature Service) CPA SupportGIS (3d GIS-System)
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ConversionConversion
CityGML FME (con terra)
IFC CityGML (Forschungszentrum Karlsruhe)
original IFC model CityGML LOD 1 CityGML LOD 2 CityGML LOD 3 CityGML LOD 4
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ViewerViewer
LandXPlorer (C++) 3D Geo, Potsdam
Hasso-Plattner-Institute(University of Potsdam)
Aristoteles 3D-Viewer (Java) IGG, University of Bonn
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Target application areasTarget application areas
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Application scenario 1: Noise immision mappingApplication scenario 1: Noise immision mapping
EU Directive: Minimisation of noise immissions
Calculation of noise immission maps for whole North Rhine-Westphalia
Data provision and exchange via CityGML using web services (WFS, WCS, WMS):
8.4 million 3d buildings in LOD 1
3d street network in LOD 0, with additional noise related attributes
3d rail network in LOD 0
3d noise barriers in LOD 1
Digital terrain model (10 meter resolution)
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Application scenario 1: Noise immision mappingApplication scenario 1: Noise immision mapping
Noise immsion mapsreported to EU
(via WMS service)
Noise immision simulation
3d geodata in CityGMLas input for the
calculaion of noise immision maps
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Application scenario 2: Homeland securityApplication scenario 2: Homeland security
Testbed OWS-4 of the Open Geospatial Consortium (OGC) Setting:
Explosion of a „dirty bomb“ in the New York harbour
Task:Support the planning committee in the construction of an emergency hospital
Find the appropriate location
Identify best fitting existing building (size, room layout, air conditioning for decontaminations, etc.)
Thematic queries & visual inspections
Link different web services and client applications Data formats: CityGML and IFC
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Application scenario 2: Homeland SecurityApplication scenario 2: Homeland Security
CityGML building visualised using LandExplorer from outside (left)
room-based representation of the security level (right)
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
http://www.opengeospatial.org/pub/www/ows4/index.html
Application scenario 2: Homeland SecurityApplication scenario 2: Homeland Security
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
ContentContent
Introduction to CityGML General characteristics
Modularisation
Coherence of semantics and geometry
Multi-Scale modelling
Terrain Intersection Curve (TIC)
External references
Appearances
Application Domain Extensions (ADE)
Implementation, Conversion, Viewer Target application areas
Noise immision mapping
Homeland Security
CityGML code example: Building in LOD 3
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML code example: Building in LOD 3CityGML code example: Building in LOD 3
<?xml version="1.0" encoding="UTF-8"?>
<CityModel xmlns="http://www.opengis.net/citygml/1.0" xmlns:bldg="http://www.opengis.net/citygml/building/1.0"
xmlns:gml="http://www.opengis.net/gml" xmlns:xlink="http://www.w3.org/1999/xlink"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.opengis.net/citygml/building/1.0 ../CityGML/building.xsd">
<gml:description>This file contains four buildings which are automatically converted from IFC models. This listing only shows an excerpt. The full dataset can be downloaded from http://www.citygml.org (example dataset for “four buildings in LOD3”)</gml:description>
<gml:name>IFC_Building_Variant</gml:name>
<gml:boundedBy>
<gml:Envelope srsName="urn:ogc:def:crs,crs:EPSG:6.12:31467,crs:EPSG:6.12:5783">
<gml:pos srsDimension="3">5429999.751795 3449999.751795 0.0</gml:pos>
<gml:pos srsDimension="3">5430023.2 3450021.2 20.0</gml:pos>
</gml:Envelope>
</gml:boundedBy>
…
<cityObjectMember>
<bldg:Building gml:id="GEB_TH_IFC_Building_Variant_GEB_75">
<gml:description>Building in LOD 3</gml:description>
<gml:name>Building-ADT-2006</gml:name>
<externalReference>
<informationSystem>http://www.iai.fzk.de/raw/pages/german/projekte/VR-Systeme/html/Download/
</informationSystem>
<externalObject>
<uri>urn:ifc:oid:0deJpNQ05BvwV03c405oVp</uri>
</externalObject>
</externalReference>
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML code example: Building in LOD 3CityGML code example: Building in LOD 3
<bldg:boundedBy>
<bldg:RoofSurface gml:id="GEB_TH_IFC_Building_Variant_DACH_136">
<externalReference>
<informationSystem>http://www.iai.fzk.de/raw/pages/german/projekte/ VR-Systeme/html/Download/</informationSystem>
<externalObject>
<uri>urn:ifc:oid:3CPSkwS7f9QRfhfr5gf7dq</uri>
</externalObject>
</externalReference>
<bldg:lod3MultiSurface>
<gml:MultiSurface>
<gml:surfaceMember>
<gml:Polygon>
<gml:exterior>
<gml:LinearRing>
<gml:posList srsDimension="3">5430006.994499969 3449999.850802998 9.141580054626465 5430007.093499946 3449999.7517950004 8.970100114212036 5430000.906494903 3449999.7517950004 8.970100114212036 5430001.005499649 3449999.850802998 9.141580054626465 5430003.999999809 3450000.9735459564 11.086200187072754 5430006.994499969 3449999.850802998 9.141580054626465</gml:posList>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</gml:surfaceMember>
<gml:surfaceMember>
<gml:Polygon>
<gml:exterior>
<gml:LinearRing>
<gml:posList srsDimension="3">5430006.920299816 3449999.925 8.870099971160888 5430006.845300007 3450000.000000003 8.999999949798584 5430003.999999809 3450001.066800046 10.847800204620361 5430001.154700088 3450000.000000003 8.999999949798584 5430001.079700279 3449999.925 8.870099971160888 5430006.920299816 3449999.925 8.870099971160888</gml:posList>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</gml:surfaceMember>
…
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML code example: Building in LOD 3CityGML code example: Building in LOD 3
</gml:MultiSurface>
</bldg:lod3MultiSurface>
</bldg:RoofSurface>
</bldg:boundedBy>
<bldg:boundedBy>
<bldg:WallSurface gml:id="GEB_TH_IFC_Building_Variant_WAND_78">
<externalReference>
<informationSystem>http://www.iai.fzk.de/raw/pages/german/projekte/ VR-Systeme/html/Download/</informationSystem>
<externalObject>
<uri>urn:ifc:oid:2es$8LnAD9UxRIGzY8UaVK</uri>
</externalObject>
</externalReference>
<bldg:lod3MultiSurface>
<gml:MultiSurface>
<gml:surfaceMember>
<gml:Polygon>
<gml:exterior>
<gml:LinearRing>
<gml:posList srsDimension="3">5429999.999999809 3450004.4950001715 6.0599999968 5429999.999999809 3450004.4950001715 4.800000021324157 5430000.119999695 3450004.4950001715 4.800000021324157 5430000.180000114 3450004.4950001715 4.800000021324157 5430000.3 3450004.4950001715 4.800000021324157 5430000.3 3450004.4950001715 6.059999996886253 5430000.180000114 3450004.4950001715 6.059999996886253 5430000.119999695 3450004.4950001715 6.059999996886253 5429999.999999809 3450004.4950001715 6.059999996886253</gml:posList>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</gml:surfaceMember>
…
</gml:MultiSurface>
</bldg:lod3MultiSurface>
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
CityGML code example: Building in LOD 3CityGML code example: Building in LOD 3
<bldg:opening>
<bldg:Window gml:id="GEB_TH_IFC_Building_Variant_OEFF_OBJ_80">
<externalReference>
<informationSystem>http://www.iai.fzk.de/raw/pages/ german/projekte/VR-Systeme/html/Download/ </informationSystem>
<externalObject>
<uri>urn:ifc:oid:3VkZRUoa97GgMdD342zHck</uri>
</externalObject>
</externalReference>
<bldg:lod3MultiSurface>
<gml:MultiSurface>
<gml:surfaceMember>
<gml:Polygon>
<gml:exterior>
<gml:LinearRing>
<gml:posList srsDimension="3">5430000.119999695 3450008.940000343 2.99999994979 5430000.180000114 3450008.940000343 2.9999999497985836 5430000.180000114 3450008.940000343 1.920000026092529 5430000.180000114 5430000.180000114 1.860000083312988 5430000.119999695 3450008.940000343 1.860000083312988 5430000.119999695 3450008.940000343 2.9999999497985836</gml:posList>
</gml:LinearRing>
</gml:exterior>
</gml:Polygon>
</gml:surfaceMember>
…
</gml:MultiSurface>
</bldg:lod3MultiSurface>
</bldg:Window>
</bldg:opening>
…
</bldg:WallSurface>
</bldg:boundedBy>
</bldg:Building>
</cityObjectMember>
</CityModel>
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Search the web for further examples… e.g.Search the web for further examples… e.g.
http://www.iai.fzk.de/www-extern/index.php?id=1412
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Search the web for further examples… e.g.Search the web for further examples… e.g.
http://www.iai.fzk.de/www-extern/index.php?id=1470
4th of March, 2008Alexandra Stadler, Thomas H. Kolbe: CityGML – Modelling our environment
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Chair of Methods of Geoinformation ScienceChair of Methods of Geoinformation Science
Thank you…Thank you…
One thing we would really like to know:
What do YOU think about CityGML?
CONTACT INFORMATIONProf. Dr. Thomas H. Kolbe, Claus Nagel, Alexandra Stadler
{ kolbe | nagel | stadler } @ igg.tu-berlin.de
Technische Universität BerlinInstitute for Geodesy and Geoinformation Science
Chair of Methods of Geoinformation Science