1. Legible Cities: Focus-Dependent Multi-Resolution Visualization of Urban Relationships Remco Chang Department of Computer Science UNC Charlotte Ginette Wessel College of Architecture UNC Charlotte Robert Kosara Department of Computer Science UNC Charlotte Eric Sauda College of Architecture UNC Charlotte Bill Ribarsky Department of Computer Science UNC Charlotte

2. 2/19 Legible Cities: Motivation While working on a graphics problem to render large urban environments [1], we realized… Visualizing a city should be more than rendering its geometric components There is a lot of information directly tied to geographic locations Question: how do people think about a city? [1] Remco Chang, Thomas Butkiewicz, Caroline Ziemkiewicz, Zachary Wartell, Nancy Pollard, William Ribarsky. Hierarchical Simplification of City Models to Maintain Urban Legibility. ACM SIGGRAPH 2006 Technical Sketch

3. 3/19 Legible Cities: Survey How do you perceive the city? Describe New York City… Response 1: “New York is large, compact, and crowded.” Response 2: “The area where I lived had a strong mix of ethnicities.” Geometric,Information,View Dependent (Cognitive)

4. 4/19 Legible Cities: Demo System Demo

5. 5/19 Legible Cities: Research Collaboration Urban Visualization 3D Models of the City Information Display Embedded in the City User Interaction for Choosing Point of View Architecture Theories of City Design and Spatial Structure City Conveys Meaning through Visual Qualities Individual’s Experience of a City (Geometric) (Information) (View Dependence)

6. 6/19 Legible Cities: Geometric – Theory of Urban Legibility Mental Sketch Maps of Cities Finding commonalities Elements of Urban Legibility Urban Theorist Kevin Lynch Boston, MA UNC Charlotte Campus Boston, MA

7. 7/19 Legible Cities: Geometric Modeling Path Edge DistrictNode Landmark Definable Elements in the City “Imageability” Identity, Recognition, Meaning Spatial Understanding of the City using Lynch’s Rules of Urban Legibility Kevin Lynch. The Image of the City. Cambridge: MIT Press, 1960.

8. 8/19 Legible Cities: Information Modeling – Iconology Robert Venturi and Denise Scott Brown Iconology Signs, Symbolism, Information Information Overlay R. Venturi, D. S. Brown, and S. Izenour. Learning form Las Vegas.Cambridge: The MIT Press, 1977.

9. 9/19 Legible Cities: View Dependence - Experiential Gordon Cullen Understanding of Architecture is based on optics, place, and content Experience of Movement, Uncovering, and Texture G. Cullen. The Concise Townscape. Oxford: The Architectural Press, 1961.

10. 10/19 Legible Cities: Interpretation of Urban Theories Geometric Hierarchical building clustering using the theory of Urban Legibility Information Matrix view shows information about building clusters Parallel coordinates show relationships between dimensions View Dependence (Cognitive) 2D translation of yellow sphere changes the position of focus Z-axis zooming changes the degree of focus

11. 11/19 Legible Cities: Coordinated Views Everything is designed around “clusters of buildings” Coordinate clusters using colors Proximity – Gradient from Red to Blue Selection - White

12. 12/19 Legible Cities: Querying Identifying areas with specific attributes

13. 13/19 Legible Cities: How To Use the System Using 2000 US Census Data of Charlotte (Mecklenburg County) NC Looking at: Ethnicity Citizenship status Income Housing Information etc. Other dimensions can be used: Crime rate, traffic, etc

14. 14/19 Legible Cities: Scenario 1: Identifying Neighborhoods Task: Find areas around downtown Charlotte with high Hispanic populations Select in the parallel coordinates view… Finding additional information about High Hispanic population regions Correlations with other dimensions…

15. 15/19 Legible Cities: Scenario 2: Segregation

16. 16/19 Legible Cities: Scenario 3: Comparing Regions Davidson, NC Downtown Charlotte, NC

17. 17/19 Legible Cities: Expert Evaluation With 14 Expert Geographic Information System (GIS) Users Center of Real Estate at UNC Charlotte UNC Charlotte Urban Institute Charlotte Mecklenburg County GIS Office Charlotte Mecklenburg County Planning Department Charlotte Mecklenburg County School Systems Private Real Estate Developers Feedbacks are very positive… “Your tool is providing an on-the-fly, interactive way of noticing nearby statistical data and their relationships” “Your focus area and peripheral areas are cohesively orientated… Changing the level of detail in other software programs is cumbersome [because it requires] running multiple repetitive queries...”

18. 18/19 Legible Cities: Summary Urban Visualization Geometry Information View Dependence Contribution Interpretation and visual implementation of Architectural theories Implementing urban theories that are qualitative by nature View-Dependent, Multi-Resolution display Don’t have to zoom in and lose contextual information Allows the user to explore the city while retaining spatial awareness

19. 19/19 Questions? Thank you! www.viscenter.uncc.edu

20. 20/19 Legible Cities: Backup Slides

21. 21/19 Legible Cities : Three Modalities Geometric Focus Dependent Information “New York is large, compact, and crowded.” “The area where I live there has a strong mix of ethnicities.”

22. 22/19 Legible Cities: Information Theory - Koolhaas Rem Koolhaas Economic and Political Issues Study of Symbolism Information Overlay City.org Approach Rem Koolhaas. S,M,L,XL. New York: The Monacelli Press, Inc., 1998