Quantified Savagery

Where Personal Data Runs Wild

Another Quadtree Map Rendering

This will be a quick post: I’ve got another population-based map rendering to share, based on the work described in this post.

The Rendering

This rendering uses tiles at Google Maps zoom level 14:

I decided to experiment with solid shading rather than wireframe for the tiles. This cuts down on the Moiré effect in densely populated areas.

The original is a whopping 1 gigapixels, so I had to resize it using ImageMagick before uploading it to Picasa:

$ convert tiles14.jpg -sample 2048x2048 tiles14.2048.jpg

A few more random tidbits of information:

  • Computing the tile subdivision took one CPU-hour on my laptop, a fairly new MacBook Air.
  • At zoom level 14, tiles near the equator are roughly 1.5 miles to a side. (Tiles further north or south are shorter in the north-south direction due to distortion in the Mercator projection.)
  • The Nile is clearly visible between the Nile Delta and Aswan.

Next Post

In my next post, I’ll dive into six months of journal entries from a six-month bike trip that Valkyrie Savage and I took back in 2010.