OpenStreetMap import

Autogen Scenery

Started in	11/2013
Description	Improved autogen support for FlightGear using OSM data
Contributor(s)	radi, vanosten, Soitanen, portreekid
Status	Under active development as of 02/2016
Topic branches:
$FG_SRC	https://gitlab.com/osm2city/osm2city/
fgdata	https://gitlab.com/osm2city/osm2city-data/

With the recent license change, we'll be able to use OpenStreetMap data in the official FlightGear scenery. Some of the most interesting things to import from OpenStreetMap are shared objects (generic models like windturbines, power lines, water towers).

This article lists open questions, ideas and planes related to the import process.

Object types

This table lists models from the FlightGear scenery database, together with a corresponding OSM tag.

	Tag	Model	Number of objects	In OSM 25.03.2014
Antennas	tower:type=communication man_made=antenna	Models/Communications/radio-*.xml	36,126 946	56,307 2,282
	man_made=communications_tower	Models/Communications/fernmeldeturm_gruenwettersbach.xml	1 584	2,905
Chimneys	man_made=chimney	Models/Industrial/generic_chimney_01.xml	6,486	10,080
Cooling towers	man_made=cooling_tower	Models/Power/coolingtower.xml	251	379
Lighthouse	man_made=lighthouse	Models/Misc/generic-lighthouse.xml	5,148	6,658
Obelisks	man_made=obelisk	Models/Misc/generic_monument_01.ac	57	117
Power pylons	power=tower	Models/Power/generic_pylon_*.ac	2,760,804	5,465,288
Radomes	tower:construction=dome	Models/Communications/radome-*.xml	37	59
Tanks	man_made=fuel_storage_tank man_made=storage_tank man_made=tank	Models/Industrial/GenericStorageTank*m.xml	46,993	689 90,774 3,847
	man_made=gasometer	Models/Industrial/Gasometer.xml	4,423	11,527
Survey points	man_made=survey_point	Models/Misc/trigpoint.xml	271,676	281,804
Traffic signs	highway=stop	Models/StreetFurniture/Stop-Sign.ac	68,443	128,354
Water towers	man_made=water_tower	Models/Industrial/water-tower.ac	17,132	31,366
Windturbines	generator:source=wind power_source=wind	Models/Power/windturbine.xml	79,636	121,228 31,565
	manufacturer=Vestas manufacturer:type=V 80	Models/Power/vestas-v80-sea.xml	39	1344 52
	man_made=windmill	-	3,928	5,961
Total			3,302,125	6,252,586
Churches	anemity==place_of_worship	Models/Misc/generic_church.ac	298	644,805
Petrol Station	anemity==fuel	Models/Commercial/Petrolstation1.ac	28	244,986
Summit Cross	summit:cross=yes	TODO	0	1120

http://taginfo.openstreetmap.org/keys/ lists all tags.

Questions/problems

• Should we remove shared objects that are currently in the database, if they are not present in OSM?

  Gijs 16:18, 14 September 2012 (EDT): OSM still lacks a lot of data, so we cannot state that something doesn't exist if it isn't included in the OSM data. We can be fairly sure though that something exists (or existed) if it is present in OSM.

  Ambush (talk) 11:37, 15 December 2013 (UTC) It's right way to get GIS data from one worldwide specialized source with excellent support from a large community. If OSM have not some data existing in real world, it's better to add this data to OSM and get it back instead of support two GIS databases with duplicates.

• In order to prevent us from adding duplicates, a certain radius around the (OSM) object location should be checked for the presence of objects. What would be a good radius?
• In what group should the objects end up? There is an "OSM" group, but there are also specific "WINDPOWER" and "POWER" groups.

Import process

1. Retrieve a node from the OSM data.
   • OSM data is already available in the database, so we can take the data directly from there, rather than re-importing from OSM.
2. Assign a corresponding FlightGear model (from the #Object types table).
   • Skip the node if their is no fitting object.
3. Check for duplicates within ... meters from the object location.
4. ...
5. For power pylons: Run pylon-headings.pl (from scenerytools) to properly align the pylons in the direction of their cables.
6. ...
7. Calculate elevation.
8. ...
9. Push to object database.

overpass turbo

The overpass turbo webservice is a quick & easy way to download objects from OSM which match the desired criteria (e.g. all terminal buildings in europe) http://overpass-turbo.eu/

here is an example to get the lon/lat center of each building - no need to run osmconvert anymore!

[out:xml][timeout:25];
// gather results
(
  // query part for: “amenity=place_of_worship”
  node["amenity"="place_of_worship"]({{bbox}});
  way["amenity"="place_of_worship"]({{bbox}});
  relation["amenity"="place_of_worship"]({{bbox}});
);
// print results
out center;
>;
out skel qt;

osmconvert

wind turbines and power pylons are most of the time easy to handle nodes in OSM. But petrol stations or churches are often ways - not as easy. The tool osmconvert can convert ways (outline of a building or an area) into nodes(lat/lon points with tags) Example: osmconvert input.osm --all-to-nodes | grep -v "<node .*/>" > out.osm

http://wiki.openstreetmap.org/wiki/Osmconvert

From the resulting .osm file it is very easy to generate a .stg file for test in flightgear (with some fixed dummy elevation) and then upload to http://scenemodels.flightgear.org (correct elevation will be calculated on the the server side) (with a script similar to this one: User:Laserman/gpx2stg.py )