3D Cadastre – Dream or Reality?
Nick Land
Context
20 Years
Cadastral Trends
•
Security of tenure (ownership)
•
Support for land markets (value)
•
Sustainable development (use)
-
Rights and restrictions
•
Efficient & effective land administration
•
Extending the use & value of the cadastre
Why do we need a 3D cadastre?
• Address
the trends in
cadastre
• Urbanisation
• Complexity
of
structures & related
rights
On & above ground
- Sub-surface
-
Not a new concept
No ‘true’ 3D cadastres exist
•
Register volumes in land (public) registers, but not included in
cadastral map
•
Register only a subset of objects
-
Apartment blocks
-
Utilities
•
Register new constructions only
•
No widely accepted definition of 3D cadastre
Definition (FIG)
•
A 3D parcel is defined as the spatial unit against which
(one or more) unique and homogeneous rights (e.g.
ownership right or land use right), responsibilities or
restrictions (RRRs) are associated to the whole entity
•
Homogeneous = the same combination of rights equally
apply within the whole 3D spatial unit
•
Unique = the largest spatial unit for which this is true
How to
Implement?
GIS Technology
GIS Functionality Continues to Improve
•
Mapping & Editing
•
Imagery
•
LiDAR
•
Mobile
•
Cloud
•
Apps
•
3-D
•
4-D & Real Time
ArcGIS is a 3D GIS
Collect
Manage
Share
Visualise
&
Analyze
3D Data types in the Geodatabase
•
Vector feature classes with X,Y,Z geometry
-
3D Points
3D Lines
3D Polygons
•
Elevation grid rasters (DTM/DEM)
•
Terrains (TIN, Point cloud, surface)
•
Mosaics of LAS LiDAR datasets
•
Multipatch (volumetric bodies)
Introducing Multipatch
•
•
•
A geodatabase feature type for 3D objects.
Collection of triangles, triangle strips, triangle fans, and rings
Stores texture image, colour, transparency, and lighting vector
information within the geometry
Collections can be complex
•
A single composite multipatch can contain
multiple patches of varying types
Textures can be applied
• Two rings and one triangle strip
• Different textures for roof, floor and walls
3D Cadastre
Concepts of 3D Cadastre
•
Full 3D cadastre
•
3D tagging
•
Hybrid 3D Cadastre
•
4D Cadastre – Time as the fourth dimension
The hybrid solution – All in one database
•
Supports the identification of a land unit
•
Supports boundary definitions
•
Supports and maintains topological relationships
2D
3D
Survey network
Data Maintenance
Identification
Spatial relationships
Boundary Definition
•
Allows maintenance in both 2D and 3D
Spatial analysis
•
Allows display of complex spatial relationships
•
Allows spatial analysis
•
Allows maintenance of other types of objects
Data Maintenance
Spatial analysis
Identification
3D Cadastre – Hybrid Solution
•
2D Parcels; 3D Objects
•
Legal & Physical Objects – Above & below ground
3D Cadastre
•
Visualisation
3D Cadastre
•
Spatial Analysis e.g for objective, market valuation
Esri’s 3D Urban Information Model
•
Simplifies the creation, maintenance and usage of 3D cities
Built Environment
Buildings & Building Interiors
Transport & Utility Networks
Installations
Trees
Legal Environment
3D Zoning
3D Land Ownership
Natural Environment
Land Cover
Atmosphere
Geology
Template for
download
2D to 3D: Data Collection
Photogrammetric data collection direct into ArcGIS
2D to 3D: Add Heights to 2D Building Footprints
•
Point clouds from aerial LiDAR …
•
… and from new sources like oblique imagery stereomatching
LiDAR point cloud
Geoprocessing to extrude
footprints
Best practice 3D workflows, example models and sample data, available at
http://resources.arcgis.com/en/communities/city-engine/, and at
http://resources.arcgis.com/en/communities/3d/.
2D to 3D: Procedural modeling
3D model creation using rules / algorithms
•
Base geometry
•
Procedural rules
Base geometry
Iterative refinement
Final 3D model
iteratively refine a design by creating more and more detail
3D models: CityEngine – WebScene
http://www.arcgis.com/apps/CEWebViewer/viewer.html
?3dWebScene=9c0e319bfaff4d33a0fe2da97c2c3fd7
Analyze
Maximum
visible building
height
Security camera
coverage
Skyline analysis
Volumetric
Shadows
3D routing
Volumetric Glare
Share
WebGIS
•Publish Virtual Cities as 3D services
•KML
Post to ArcGIS.com
CityEngine Web Scenes
Create
screenshots
Export video animations
Mobile
3D
Extending use of Cadastre
Urban planners / Emergency Response / Public safety
Rotterdam
City of Portland
Masdar city
Singapore
Brisbane
Philadelphia
Pasadena
Sydney
Other (non-technical) considerations
•
Legal
•
Institutional
•
Needs
•
Costs and benefits
Conclusions
•
•
Today’s GIS technology allows us to:
-
Model the world in 3D
-
Collect, manage, edit, visualise, analyse & share 3D models
-
Hybrid 2D/3D Cadastre offers cost effective solution
The bigger questions are:
-
What are the ‘real’ needs?
-
Are the costs justified by the benefits?
-
What changes are required to the legislation?
For more information:
•
FIG Com. 3 & 7 Working Group on 3D Cadastre
-
http://www.gdmc.nl/3DCadastres/
•
www.esri.com
•
Nick Land: nland@esri.com