Fast contour lines using plain PostGIS

0. What’s this and what’s not

Last years have seen the rise of data sources with IoT, AoT, mobile devices, beacons, etc. The study of this data can be quite profitable, but there are laws against the use of personal data as is. Or any piece of data that can lead to the identification of an individual. In EU, the General Data Protection Regulation (GDPR)[1] bill will define...

First of all, what is an isovist? It’s simply the same as a viewshed… and what the heck is a viewshed? Let’s go to the Wikipedia:

To write te article Spies in the sky, the authors needed a multi-step analysis, explained here

If you want to work with official buildings data in Spain, you can go to Sede Electrónica del Catastro and download the public available vector there. Within the data package, you’ll find a CONSTRU dataset with building information.