3D Data Representation with the Thematic Mapping Engine
July 24th, 2008 | Published in Google Maps
Thematic Mapping Engine (TME) lets you create thematic or statistical maps on-the-fly in the web browser. It then returns a KMZ file which you can view directly with the Google Earth browser plugin, or you can download to view in the regular Google Earth.
TME supports various thematic mapping techniques like choropleth maps, proportional symbol maps and animated maps. The goal of this project has been to explore the pros and cons of doing thematic mapping with KML. You can read about the various techniques on the thematic mapping blog
The Thematic Mapping Engine is also a good example of what you can achieve with open source tools and datasets in the public domain:
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A world border dataset is loaded into a MySQL database. The same database contains tables with statistics from UNdata.
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A PHP script generates KML by querying the database and adding styles according to the parameters given by the user.
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Map legends are generated on-the-fly using the GD graphics library.
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All files are zipped into one KMZ file which is stored on the web server. A link to the file is returned to the user.
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The user interface is build with Ext JS and AJAX techniques.
So far, you can only create thematic maps with statistics from UNdata (http://data.un.org). The possibility to add your own data will be supported in a future release.
Two examples (all statistics from UNdata):
Infant mortality rate in 2005 visualized as a prism map (extruded polygons).
Mobile phone subscribers in 2004 visualised with proportional 3D objects (mobile phone model downloaded from 3D Warehouse).
