Saturday, 12 June 2010


I was asked on Friday if I could get the tiles out of Google StreetView for a particular location

- they wanted to create some graphics for the event from them. A preliminary google found this - after trying the code in Processing, and being reminded what a poor environment it is - wouldn't even let me resize the editor window, might as well have been using it on a mobile phone - I ported the main method to Python, and managed to get the tiles to satisfy the original request. At Zoom level 3 Google give us a 4x7 matrix of 512x512 tiles. Not 3x6 as suggested here. From looking at the tiles, it looked like Google were serving up a standard 360° 2:1 Equirectangular projection. I manually composited the tiles into one 3584x2048 (7x512, 4x512) - and immediately, I could see that it wasn't.

What we have is more than 360°, and an image that has a black bar at the bottom, meaning that it isn't 2:1. So, by a process of trial and error I worked out the final image size of 3328x1664.

Now I had a compliant Equirectangular, I couldn't leave it at that, I had to see if I could get it into the dome. Took about 20 minutes to grab the bits I needed from my EquiFlickrAuto app, and it was done - StreetView in the dome! Now I need to get a decent way of selecting the location, maybe just start it from a particular location, and use a Wii controller to move through the Panos. The google maps API seems completely Browser/Javascript focused - although this guy has managed to find the URL based API....