US Constituency Vector Tiles

This repo contains scripts for generating vector tiles of all US constituencies, based on data from Who's On First.

The data used here is potentially out of date or incomplete. This code is mainly for educational purposes.

Setup

These scripts assume a few basic dependencies. Most of these can be installed through Homebrew on a Mac.

node wget sqlite3 bunzip2 tippecanoe

There are also some node dependencies, so dont for get to

npm install

Usage

Generate MBTiles

The script generate_tiles.sh will take care of downloading and processing the data into an .mbtiles file. The general steps are

• Download whosonfirst constituency data
• Extract the GeoJSON using sqlite3
• Post-process the data with ./generate_layers.js to add tippecanoe metadata
• Run tippecanoe on the GeoJSON to output an .mbtiles file

Once done, the generated .mbtiles file will be in the ./tiles folder. You can find the additional downloaded and processed files in ./data.

Serve vector tiles

Once the MBTiles have been generated, you can start the node server to server:

node server.js

Going to http://localhost:3030 should serve the index.html file, that will render the tileset using Mapbox GL

There is also a view with a Mapbox basemap at http://localhost:3030/basemap. You will need to add the MAPBOX_ACCESS_TOKEN variable to a .env file (env variables are being loaded via dotenv).

Attribution

Thanks to Geocode Earth for graciously building and hosing the whosonfirst data

Most of the server-related code was inspired by Tileserver GL