Google Maps gives you API for adding additional map layers. This software implements a map tile server for a heatmap layer.

Dependencies

• Python 2.5 (needs sqlite)
• Pygame or PIL
• Aspen 0.8 (Python webserver)

NB: Pygame is a lot more trouble to install than PIL. For example, you will need to use a nightly build since saving to PNG is broken in 1.8.0. You will also need to install numpy before you can use Pygame with Gheat. That's the price of performance: Pygame is three or four times faster than PIL.

How it Works

This is a standalone web app that responds to URLs of the form /<color_scheme>/<zoom>/<x>,<y>.png with 256px by 256px images like this:

You tell Google Maps (via their API) to place these images over your embedded map. The images are increasingly transparent as the zoom level increases, so they make a nice overlay.

Full documentation is available.