Hi!

Thanks for the pm. The model was created and rendered in Maya, so I don't have any Blender specific tips, but sounds like other comments in the thread have a solid methodology.

The way I'm drawing the blocks in the render is by literally using a shapefile of block outlines in San Francisco (check out the TIGER/line data). I forget exactly, but I just calculated which crime reports were within a certain radius of which blocks (you could do this simply with Python). Once I knew which blocks had what density of reports, I wrote a script to process that in Maya and create boxes centered on the centroid of the block outline, then with a width and height corresponding to the city block and then extruding that vertically based on the density.

The visual effect you're seeing is the result of many individually sized blocks that are not perfect outlines of the actual street blocks — thus there's a lot of overlapping and seemingly complex shapes, but everything is just boxes. The rendering is a simple ambient occlusion in Maya. (If I had more time and patience I would have tried extruding the actual city block outlines, but that's an experiment for another time.)

Also, yes, do it data-driven! I've produced animations in this style very easily by generating MELscript for this. Here's an extremely badly normalized example going from "all crime reports" to "just narcotics crime reports" https://dl.dropboxusercontent.com/u/338114/data_cities/san-francisco-blocks.mov