This document discusses the advantages of using a database model over file-based models for 3D city modeling. A database model provides a data structure, data model, and relational links that allow the city model to be dynamic, securely accessed and updated over time. This protects the investment in collecting the 3D data and saves money by facilitating ongoing use and management of the digital city model.

1. Changing our perspectives from ‘collection’ to ‘utilisation’ Protect the investment made acquiring your 3D digital city with effective data management. Stephen Rixon Managing Director Met Geo Info Ltd. www.metgeoinfo.com

2. Content What is a City Model? Why would you want to model a City? How do you model a City? “ I have my City model. Now what?” File-based models vs. Database models

3. City Modelling: What is it?

4. City Modelling: What is it? Level of detail (LoD) 1 – LoD 3…

5. City Modelling: What is it? ..to LoD 4: Interiors

6. City Modelling: Why? To improve decision making, and To save time and money in the decision making process Application areas : Information management Conservation Urban planning Public consultation

7. Information Management

8. Urban Planning

9. Information Management Solar radiation models Locating ‘alternative energy’ generation’ units, and calculation of energy requirements for heating/cooling

10. Urban Planning

11. Public Consultation 1

12. Public Consultation 2

13. Public Consultation 3

14. Public Consultation 4 Solid models: (also termed LoD5 ) 3m x 3m physical printed model

15. City Modelling: the How Creation Management Visualisation Input: Point Cloud Data Aerial Photography 3D Data Providers Output: Rendering (stills/video) Interactive viewers Analysis (2D/3D)

16. IT convergence (GIS integrated with mainstream IT) Advancements in 3D visualisation Advances in data capture LiDAR (airborne & ground based) Photogrammetry: Vexcel UltraCAM Terrestrial Laser Scanning City Modelling: the How

17. City Modelling: the How “ off-the-shelf ” models generated for a mass-market. There is now a wide availability of 3D data… so what’s the problem?

18. 3D data is predominately: Graphics based CAD based (Flat) File based Static a snap-shot-in-time …. City Modelling: the How

19. 3D data is predominately: Graphics based CAD based (Flat) File based Static Database: The advantage The solution is to give your model a: Data Structure Data Model Relational Files Dynamic a snap-shot-in-time …. … a fully maintained digital city

20. Database: The advantage Data Structure Off-the-shelf model: faces

21. Database: The advantage Data Structure Database: line model

22. Database: The advantage Data Structure Database: faces generated on the fly

23. Input line structure Corresponding 3D Model Database: The advantage Data Structure

24. Database: The advantage Data Model Unit Object 2 Object 1 Object 3 Detail element complex Main element complex facade roof

25. LoD 1 LoD 2 LoD 3 Database: The advantage Data Model

26. Database Linkage between the model and mass storage device Data model: Persistency of objects (LoD) Data Sharing tools middleware apps / on-the-fly transactions Data Management tools Indexing Transactions Replication Locking Security Database: The advantage RDBMS

27. Database: The advantage Dynamic CityGRID Modeler tool:

28. Database: The advantage Dynamic CityGRID Modeler tool:

29. Database: The advantage Dynamic

30. Database: The advantage Dynamic

31. Summary A Database Model gives you the tools to: keep your data safe ; Keep your data current ; Keep your data accessible ; Protect your investment made in the 3D data and save your money