Leveraging Interactive AJAX Web Tools for Online Maps

Transcription

1 Leveraging Interactive AJAX Web Tools for Online Maps Presentation at GeoWeb 2009 Academic Track Steven Romalewski CUNY Mapping Service The Graduate Center / City University of New York July

2 The Challenge The Long Island Index wants to show (among other things): 1. Transit connections between where people live and where they work across Nassau and Suffolk counties; 2. Long Island s downtowns in relation to multi-family housing density plus access to parks and open space; 3. The communities with the highest proportion of multi-family units compare with regional views of age of housing stock; 4. Income attributes of any given community plus its concentration of rental units; 5. Brownfield locations compared with population patterns by race/ethnicity; 6. All of this and more with aerial photography on a map, all at once, interactively, online. GeoWeb 2009 CUNY Mapping Service 2

3 Mapping Multivariate Data Some traditional cartographic techniques Multiple symbol types Small multiples Multivariate dot density maps Different textures Transparency (eg., color coded DEM draped over hillshade) GeoWeb 2009 CUNY Mapping Service 3

4 Map display on the desktop Integrates many of the multivariate approaches GeoWeb 2009 CUNY Mapping Service 4

5 Map display on the desktop Also can leverage emerging geostatistical software packages with multi-framed display of integrated data Data_Mining_in_GeoVISTA_Studio.pdf GeoWeb 2009 CUNY Mapping Service 5

6 Map display on the desktop But How does this translate online? GeoWeb 2009 CUNY Mapping Service 6

7 Online map display PROs Interactive Zoom in very close or out very far with ease Add or remove layers of data from the map Slippy maps easy to navigate CONs Single frame generally rules out small multiples Multiple symbol types (including dot density and texture) generally don t translate well for thematic/analytical maps o but they can work well overlaying roads with choropleths, for example Transparencies would work, but until recently the cumbersome nature of webpage redraws makes this clunky Also, challenge of keeping it simple while making GIS analytic tools accessible GeoWeb 2009 CUNY Mapping Service 7

8 Enter AJAX, applied to online maps Online mapping in a post-google Maps world o Ease of use and intuitive display o Relatively easy integration of multiple data sets from disparate sources (ie, mashups) o No need to click on a i tool to access attributes, or click a hand tool to pan the map, for example Open Source movement rapidly making new tools more accessible, encouraging experimentation and early deployment o Geoserver & Mapserver, OpenLayers, etc ESRI also enhancing their toolkit o New ArcGIS Server tools caching, etc Some early adopters of innovative approaches: o GeoWeb 2009 CUNY Mapping Service 8

9 New York-area examples Early 2006, CUNY Mapping Service established with broad mandate help CUNY researchers and others leverage the power of GIS in their work, and continue developing cutting-edge interactive online mapping systems 1. Long Island Index project asked us to develop interactive mapping feature for o Index background needed to make complex issues more understandable to public (esp. to visualize inter-relationships and multi-level spatial patterns) and to engage people via the Web 2. A second project is a complete overhaul of the Open Accessible Space Information System (OASIS) website ( first created in early 2000 using ArcIMS in collaboration with ESRI, USDA Forest Service, and more than 40 local NGOs, public agencies, businesses, and individuals. GeoWeb 2009 CUNY Mapping Service 9

10 A hybrid geo stack Technology choice: combination of ESRI/Microsoft with open source JavaScript frameworks ArcGIS Desktop and ArcSDE/SQL Server to manage the data sources. ArcGIS Server to generate web map services from MXDs and generate cached tiles for selected map layers. OpenLayers consumes WMS resources, manages and displays the map layers, and provides map navigation tools. Dynamic data feeds are also provided via REST web services. Ext JS provides the overall web framework and enables us to relatively easily integrate AJAX-style tools such as dynamic transparencies. With the exception of the satellite/aerial photos, we host all map layers Simply too much data to simply mash it up with a basemap from Google Maps or Microsoft and we wanted cartographic control. GeoWeb 2009 CUNY Mapping Service 10

11 The Long Island Index interactive map visualize your community in new and powerful ways Map your village When you select a village: 1. It s highlighted in orange; 2. Local statistics and charts are displayed; and 3. The overview map shows where on LI you ve zoomed to

12 See population or housing patterns in and around your community

13 Map education statistics district-by-district NEW for 2009!

14 Add transportation routes, schools, environmental sites, special districts, and more

15 The transparency slider reveals what s underneath 0% transparent 50% transparent 100% transparent

16 Compare aerial photos with Census and land use patterns 0% transparent Click on the red marker for a bird s eye view 70% transparent 100% transparent

17 Explore regional views of key demographic indicators You can zoom out to see the entire island, and then double-click on the list to zoom back in and see community-level detail.

18 For more info, contact: Steven Romalewski, Director Phone: David Burgoon, Application Architect Phone: CUNY Mapping Service at the Center for Urban Research The Graduate Center / CUNY 365 Fifth Ave., Room 6202 New York, NY GeoWeb 2009 CUNY Mapping Service 18