Cities in Space and Time: A Spatial-Temporal Visualization Model of Urban Environments

Transcription

1 Cities in Space and Time: A Spatial-Temporal Visualization Model of Urban Environments Li Yin Assistant Professor Department of Urban and Regional Planning University at Buffalo, The State University of New York Narushige Shiode Lecturer in Spatial Analysis and GIS City and Regional Planning, Cardiff University IACP 2010 June 19, Shanghai, China

2 Outline Background on 3D City Visualization CAD models and GIS models (1990 ~ 2000) Online 3D city models (2000 ~) What is missing from the current range Building a Spatial-temporal Urban GIS Model Data Source and Study Area Combining CAD and GIS Spatial-temporal representation 1: Multiple static models Spatial-temporal representation 2: temporary dynamic GIS model spatial-temporal analysis for the change of the environment.

3 Mumford s (1938) definition of cities as a product of time Kostof s (1991) account of cities as a living process rather than a static object. Space and time are two essential factors that hold the key to the understanding of many different aspects of cities.

4 Typology of 3D City Models in Terms of Their Functionality CAD (Computer Assisted Design)-based Model Aesthetic models that convey some degrees of realistic representation intended for architectural designing, presentation, and public viewing (Skyline, Multigen-Paradigm, AutoCAD, Sketchup) lack the capacity to accommodate other types of applications, such as spatial query and analysis. they usually are not geo-referenced. GIS (Geographic Information Science)-based Model

5 CAD-based 3D City Models out there Zenrin Co.

6 Typology of 3D City Models in Terms of Their Functionality CAD (Computer Assisted Design)-based Model GIS (Geographic Information Science)-based Model The limited use of 3D GIS was partly due to the inadequacy of GIS programs in their ability of 3D visualization and modeling (Shiode and Yin, 2008) and partly due to the high cost of constructing realistic 3D models in terms of time and computer hardware needed for rendering as well as time spent on learning most 3D modeling programs, e.g. CAD.

7 An Example of GISbased 3D models CommunityViz ( circuit=1&fuse=main)

8 Static 3D GIS models of cities

9 Navigable 3D GIS models of cities

10 Navigable 3D GIS models of cities

11 Online 3D Models out there Google Earth NASA WorldWind Arc Explorer Windows Live Local

12 Sufficient for applications that do not require texture data such as visibility field analysis (e.g. for allocating a cell phone base station) or environmental assessment LIDAR (LIght Detection And Ranging) Data of an Urban Area Automated Vertical Extrusion Using LIDAR Data

13 A typology of 3D urban models using different modeling methods (Shiode and Yin, 2008)

14 GIS-based 3D Models: Rezoning Analysis This image illustrates pre-war office space that is primarily vacant, floor by floor above 150 feet from the street, which makes these spaces suitable for adaptive reuse as housing. This image color codes buildings based on unused zoning floor area. A query shows all buildings built prior to 1945 Source: Environmental Simulation Center

15 GIS-based 3D Models: Urban Simulation

16 GIS-based 3D Models: Visibility Analysis View Possibilities: Views from Different Floors Yin and Hastings, 2007 State Park

17 Shadow Analysis Yin and Hastings, 2007

18 Source: Bergerman s Associate

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20 The existing range of 3D methods, however, focus primarily on the static state in that it provides a representation of the urban environment from one particular point in time, usually using the most recent dataset available. Using a 3D-GIS environment, this study attempts to build a spatial-temporal model of urban environment to help study the changes in the physical form of cities.

21 Study Area

22 3D GIS Modeling Resources NASA Worldwind Google Earth & Sketchup Yahoo Local & Maps Microsoft Local Live MSN Virtual Earth Other Examples (ArcExplorer, etc.)

23 Data Source Data Parcels Satellite Images Sanborn Fire Insurance Maps Building Facades 3D CAD Model (year 2000) Source New York State GIS Clearinghouse University at Buffalo Library University at Buffalo Library d.html, and field work Urban Design Group, University at Buffalo

24 The Structure for Building a 3D Spatial Temporal Model Building Footprints in CAD Individual GIS Augmentation First Stage 3D GIS Model for One Time Point Temporal Five 3D GIS Models for Five Time Points in Sequence Linear Second Stage 3D Spatial Temporal Model Schematic

25 1) Create a series of static 3D GIS models for different time points; 2) Combine the series of 3D GIS models developed for each time point into a single temporal model by adding time index to each 3D object; 3) Create an interface to support the visualization and study of changes in the urban landscape; 4) Conduct preliminary spatial-temporal analysis for the changes.

26 An illustrative example of urban transformation in the downtown area of Buffalo: from the small, finer buildings to the larger super-structures (the three snapshots show a portion of aerial photographs of the same location recorded in 1927, 1966, 1978, respectively).

27 Conceptual Framework

28 1966 Building Footprints of Downtown Buffalo as of 1927 Building Footprints of Downtown Buffalo as of 2000

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30 Spatial-temporal Visualization

31 3D Spatiotemporal Interface

32 Spatial-temporal Visualization

33 Selection based on the Spatiotemporal Model Highlighted Selection by the Current ArcGIS Query Tool

34 buildings are shaded by the temporal query on their year of construction. Buildings in darker shade are older construction, and the lighter shade, are more recent.

35 Lisa Cluster Map: Year of Construction Lisa Cluster Map: Building Height and Year of Construction

36 Conclusion Our model treats time and space as mutually constitutive conditions, thus allowing us to visualize the dynamic transition of an urban landscape the way an urban area evolves over a period of time including the growth and changes of street patterns, building sizes and shapes, and density as well as the general life cycle of a city as a whole.

37 New Trends in Visualization Example-Augmented Reality Augmented Reality blend virtual 3D objects into real scene obtained by camera. It can have many applications in planning, e.g. 3D models of demolished buildings can be blended into current scene, or models of future buildings can be blended into existing landscape, for the purpose of public exhibits. With the arriving of AR applications on the cell phone, public can use their cell phones to visualize buildings before they are constructed, they can point their phones at famous buildings and retrieve history and events related to the building instantly. < 景智浏览器 >- on the android platform is such an application for China. When building enters cellphone's Camera view, it's descriptions are Overlaid on top of it.

38 Thank you. Questions? Comments?