Mikael Capelle 7440596f69 Minor fixes.
2021-10-07 14:39:06 +02:00

6.6 KiB

Map generator for "BE Graphes"

The purpose of this repository is to ease the process of generating graph and mapforge file that are consistent (using the same OpenStreetMap data).

How to start?

To clone this repository:

# You need the --recursive option (--recurse-submodules with Git >= 2.13),
# you can use https or ssh, it does not matter.
git clone --recursive

# Then you need to initialize the repository, this may takes some time as it needs
# to fetch a shapefile (~500MB) on a remote server.
cd be-graphes-map-generator

If you do not plan on generating maps with coastline for mapsforge (see below), you can use the --no-shapefile option to avoid the download:

bash --no-shapefile

Folders organization

The two main folders are inputs and outputs:

  • inputs mainly contains:

    • a script to merge land/sea polygon (see below) and PBF files;
    • multiple polygon (.poly) and bounding-box (.bbox) files for specific regions;
    • PBF files downloaded organized in folder $REGION/$REGION.pbf.
  • outputs is the default folder for generated output.

Generating maps

This project can be used to generate two types of files:

  • Graph file (.mapgr) containing graph information (see OSM2Graph);
  • Mapsforge file (.mapfg) containing mapsforge data to display graph in a more visual way.

The process to generate the Mapsforge file is more complex than the one to generate graph file, and it will often take much more time. Fortunately, it is often not necessary to generate the Mapsforge file, because pre-generated files exist for most countries and regions.

Before generating the Mapsforge file, check if a file corresponding to the region you want exists on the following server:

The hierarchy of this server is similar to Geofabrik, which is the main source for our PBF files.

Step 1 - Obtaining a PBF file.

The first step is to a PBF files containining the region you want:

Using a bounding box:

bin/osmosis --rb inputs/europe/france/bretagne/bretagne.osm.pbf \ # Specify your input PBF
            --bounding-box bottom=47.160000 left=-3.855000 top=48.330000 right=-1.915000 completeWays=yes \ # Specify the bounding bo
            --write-pbf inputs/europe/france/bretagne/morbihan.pbf # Specify the output file

Using a polygon:

bin/osmosis --rb inputs/europe/france/bretagne/bretagne.osm.pbf \ # Specify your input PBF
            --bounding-polygon file=inputs/europe/france/bretagne/morbihan.poly completeWays=yes \ # Specify your bounding polygon
            --write-pbf file=inputs/europe/france/bretagne/morbihan.pbf # Specify your output file

The inputs directory contains bounding-box (.bbox) and bounding polygon (.poly) for some regions. You can find polygon for a lots of region here: (to find the id of the relation, search it on openstreetmap, e.g.

Step 1 Bis - Fixing coastlines and sea.

Important: You can skip this step if your region does not contain sea or big inner lakes, or if you do not want to generate the corresponding Mapsforge file.

You will need GDAL for this section, and the python bindings, you can usually install them using a package manager:

# pip (better with a venv!)
pip install GDAL>=3

# Debian
sudo apt install gdal python-gdal

# CentOS
sudo yum install gdal gdal-python

We need to add sea information to the PBF file to generate a correct mapsforge map. To do so, a script is provided. Run it simply:

cd inputs
./ europe/france/bretagne/morbihan.pbf

To apply the fix, you need a polygon file (morbihan.poly — not another name), in the same directory as the PBF or in the inputs/bbox directory (recommended).

This script will generate multiple intermediate files, but only two are importants:

  • inputs/europe/france/bretagne/morbihan.bbox, actual bounding-box of the PBF file — This will overwrite the old bounding-box if there was one.
  • inputs/europe/france/bretagne/morbihan_merge.pbf, merged file that you should use as input for mapsforge.

Step 2 - Generate graph & Mapsforge files

To generate both the graph file and the Mapsforge file corresponding to your input PBF, you simply need to run the script:

bash inputs/europe/france/bretagne/bretagne.osm.pbf \
                 --id FR-E --name "Bretagne" \
                 --output outputs/bretagne

This command will generate two files: outputs/bretagne.mapgr and outputs/bretagne.mapfg, you should not add the file extension when specifying --output.

You can get help about by running:

bash --help

If you use a merged file (_merge.pbf) file as input, you need to specify the corresponding bounding-box:

bash inputs/europe/france/bretagne/morbihan_merge.pbf \
                 --bounding-box inputs/europe/france/bretagne/morbihan.bbox \
                 --id FR-56 --name "Morbihan" \
                 --output outputs/morbihan

The script will automatically find the original file (morbihan.pbf) and use it to generate the graph file (using the merged file can generate unexpected result... ).

If the input PBF file correspond to a region that has been cropped, it is better to specify the polygon or bounding-box used for the generation of the PBF:

bash inputs/europe/france/bretagne/morbihan_merge.pbf \
                 --bounding-box inputs/europe/france/bretagne/morbihan.bbox \
                 --bounding-polygon inputs/europe/france/bretagne/morbihan.poly \
                 --id FR-56 --name "Morbihan" \
                 --output outputs/morbihan

If both the --bounding-box and --bounding-polygon option are specified, the bounding-box will be ignored for the generation of the graph file (the --bounding-polygon option has no effect for the generation of the Mapsforge file).

You can generate only the graph file (--graph-only) or the Mapsforge file (--mapsforge-only). With --mapsforge-only, the --id and --name options are not required.