abstreet/docs/new_city.md

Importing a new city into A/B Street

This process isn't easy yet. Please email dabreegster@gmail.com or file a Github issue if you hit problems. I'd really appreciate help and PRs to improve this.

Quick start

If you're using the binary release and have a .osm file, just do: ./importer --oneshot=map.osm.

If you're building from source, do: ./import.sh --oneshot=map.osm. If you can't run import.sh, make sure you have all dependencies.

The oneshot importer will will generate a new file in data/system/maps that you can then load in the game. If you have an Osmosis polygon filter (see below), you can also pass --oneshot_clip=clip.poly to improve the result. You should first make sure your .osm has been clipped: osmconvert large_map.osm -B=clipping.poly --complete-ways -o=smaller_map.osm.

You can also try --oneshot_drive_on_left, but you'll spot some bugs. Get in touch if you need these fixed soon or want to help.

How to get .osm files

If the area is small enough, try the "export" tool on https://www.openstreetmap.org. You can download larger areas from https://download.bbbike.org/ or http://download.geofabrik.de/index.html, then clip them to a smaller area. You can draw a clipping polygon using http://geojson.io or https://geoman.io/geojson-editor. You have to turn the coordinates from that polygon into the Osmosis format. The data/geojson_to_osmosis.py script can help with the formatting.

Including the city by default

1. Make sure you can run import.sh -- see the instructions. You'll need Rust, osmconvert, gdal, etc.

2. Use geojson.io or geoman.io to draw a polygon around the region you want to simulate.

3. Create a new directory: mkdir -p data/input/your_city/polygons

4. Create a polygon filter file in that directory using the coordinates from geojson.io. It's easiest to start with an existing file from another directory; I recommend data/input/krakow/polygons/huge_krakow.poly as a guide. You can use data/geojson_to_osmosis.py to help format the coordinates.

5. Create a new module in importer/src/ for your city, copying importer/src/krakow.rs as a guide. Edit that file in the obvious way. The main thing you'll need is a .osm or .osm.pbf file to download that contains your city. The clipping polygon will be applied to that.

6. Update importer/src/main.rs to reference your new module, following krakow as an example.

7. Update map_belongs_to_city in updater/src/main.rs

8. Run it: ./import.sh --city=your_city --raw --map

9. Update .gitignore, following krakow as an example.

Send a PR with your changes! I'll generate everything and make it work with updater, so most people don't have to build everything from scratch.

Next steps

OpenStreetMap isn't the only data source we need. If you look at the import pipeline for Seattle, you'll see many more sources for parking, GTFS bus schedules, person/trip demand data for scenarios, etc. Most of these aren't standard between cities. If you want to make your city more realistic, we'll have to import more data. Get in touch.

You may notice issues with OSM data while using A/B Street. Some of these are bugs in A/B Street itself, but others are incorrectly tagged lanes. Some resources for fixing OSM:

• https://learnosm.org
• https://wiki.openstreetmap.org/wiki/StreetComplete
• https://dabreegster.github.io/abstreet/map_parking.html