Summary
In this chapter, we finished implementing a sophisticated geospatial web application using GeoDjango, Mapnik, PostGIS, OGR, and pyproj. This application is useful in its own right as well as being a springboard to developing your own geospatial web applications.
We learned that we can easily create our own Tile Map Server using Mapnik and GeoDjango. We saw how to use OpenLayers in our own web pages and how OpenLayers can be made to work with our Tile Map Server. We learned how to intercept mouse clicks using OpenLayers and how to use JQuery's AJAX functionality to send requests to the server for processing.
We then saw how to use Proj.4 to calculate a search radius measured in degrees of latitude and longitude and how to use GeoDjango's query functions to identify features close to the point where the user clicked. We also looked at how to use GeoDjango's editing forms to let the user view and edit the contents of a geometry.
Finally, we saw how to handle the addition...
