Support for WOFF:
A reader pointed out that my Label Sphere wasn't working as advertised. I took a look at both our blogs and they both looked fine, then I realized it must be a browser issue. I looked again with Firefox and sure enough the labels were all stacked on each other at the bottom of the gadget. I made the mistake of only testing in one browser (Google Chrome).
So for anyone using IE6 (or any other outdated browser) it's time you upgrade! And if you aren't using Google Chrome you should give it a try.
My first project with Google App Engine was a Google Map that displayed temperature data for a given date. I used monthly grid data provided by NOAA. With this data the Earth is divided up into 5x5 degree grids for a total of 2592 grids. I wrote a simple Perl script to parse the NOAA data, find the min and max temperatures, generalize each temperature point into a scale of 1 (min) to 9 (max), calculate the latitude and longitude for each corner of the grid, and write a CSV file suitable for upload to the datastore.
For the backend I wrote a Python script that created a kml of the data for the requested date. In the kml, each temperature range is a separate Placemark, and within each Placemark are GPolygons representing the grid data.
Unfortunately only 1 GPolygon for each Placemark would load. So I re-wrote the Perl script to output encoded polylines instead of latitude, longitude coordinates. I also wrote a Perl modulino (ISC License) to convert a set of coordinates to an encoded polyline string.
The backend was rewritten to output the data in JSON instead of a kml.
The frontend was rewritten to create GPolygons using the encoded polylines.
This time all the polygons were created correctly. The first date I tested was 1880-01 with around 200 temperature grids. With this many grids, the tab running my map consumed over 300MB of memory. Therefore, I didn't even try loading the most recent date, as it probably had over 2000 temperature grids. My conclusion from this project is that only a few polygons can be created on a Google Map. Here is a screenshot of the application. Note that the date range is only from 1880-01 to 1880-11 so the temperature range is quite small.