This project implements Python code to create geofences using quadkeys.
Start by creating the supporting SQLite database on the data folder, named
qk-geofences.db.
Run the scripts from the sql folder in the following order: geo_fence.sql,
geo_square.sql, and ix_geo_square_square_qk.sql.
Download the country borders data file from the datasets/geo-countries
GitHub repository, and place the countries.geojson file in the data folder.
Now you can run the code that generates a country's geofence as a hierarchical
set of quadkeys: quadkeyfill.py.
Note that you must select the country name in the source file.
The polyfill.py file contains code to illustrate how a scanline polygon
filling algorithm works, without the geospatial intricacies.
It uses a NumPy array as the drawable bitmap and displays it at the end.
The query.py script contains sample code on how to query the resulting
database. It takes as input a latitude and longitude pair and displays
a (possibly empty) list of matching geofences.
The two Jupyter notebooks generate the images used in the article.
You can only run the qk-geofence.ipynb notebook after running the
quadkeyfill.py script, as it generates geofence data to the database.