EveryBlock (now launched in Chicago) just blogged about the technology they used to create their own mapping platform (not using Google or Yahoo maps). It's missing a few details no doubt, but in addition to the already open components listed here, EveryBlock (funded by the Knight Foundation, which is also making significant investments in Drupal) will ultimately make the complete recipe available. Here's the parts they're using:
For the technology-inclined reader, here’s how we put our map platform
together. All web technologies are a “stack,” like layers in a map, and our map stack starts at the top with OpenLayers, which
provides the click’n’drag’n’zoom interface. The next step down in the
stack is Mapnik, which renders geospatial data into graphical images. At the bottom of the stack is our collection of geospatial
data, which includes TIGER/Line and shapefiles from various city
governments, as well as databases and tools that operate on that data, such as PostGIS, Shapely, and OGR. Finally, the “secret sauce” layer in the stack is TileCache, which actually sits between OpenLayers and Mapnik. It provides caching of the map tiles that are generated by Mapnik and served to OpenLayers. I say “secret” because it’s transparent to both the layers it sits between, and also because it greatly speeds up the entire stack, making it possible to deploy and scale a large mapping application. It’s worth mentioning that all these layers of the stack are open source or licensed freely. If you can build and deploy a web application, you can build and deploy a complete standalone geospatial and mapping application. The tools and data are there for the taking.
How much could/should make it into Drupal? And of greatest interest to me, what can Drupal developers and deployers do to encourage the creation of shared information resources of new mapping information? (For instance, the location of all Drupal meetups, contributed by many sites and shared among them?)
UPDATE: This DrupalCon Boston session proposal on Drupal as a GIS/Mapping Platform means Drupal reality is, as usual, ahead of my imagination. It also references the in-development Open Layers module.
benjamin, Agaric Design Collective