brouter/docs/users/android_advanced.md

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Using BRouter	2

Android advanced configuration

Directory structure

BRouter uses several subdirectories inside the base directory.

directory	description
<basedir>/brouter
<basedir>/brouter/modes	routing-mode/profile mapping and route cache
<basedir>/brouter/profiles2	lookup-table and routing-profiles (*.brf)
<basedir>/brouter/segments4	routing data files (*.rd5)
<basedir>/brouter/import	allow a small file exchange with other apps
<basedir>/brouter/import/tracks	place the nogo*.gpx files here

modes contains serviceconfig.dat which defines routing-mode / routing-profile mapping and cached route results which are used for recalculations.

profiles2 contains lookup.dat (OSM tag access), serverconfig.txt and routing-profiles.

segments4 contains storageconfig.txt and routing data files (*.rd5). You can download them using the Download Manager or as described in Download Routing Segments.

Configuration files

serverconfig.txt

serverconfig.txt is used to configure download information for routing profiles and routing segments.

serviceconfig.dat

serviceconfig.dat is used to configure mapping between routing-mode and routing-profile.

storageconfig.txt

storageconfig.txt is used to specifiy additional paths which BRouter should use.

• secondary_segment_dir points to an additional directory containing routing data files. This can be located anywhere.

  When searching for datafiles, both the download manager and the router first look in the primary (brouter/segments4) and then in the secondary directory. On the other hand, the download manager always writes new datafiles to the primary directory, so the secondary directory is read-only.

  You can move datafiles downloaded by the download-manager to the secondary directory, by using a file manager, in order to free disk space on the internal card.

• additional_maptool_dir points to a directory that should be scanned for maptool-installations in addition to the standard-guesses.

Redirect files

When using the file interface with waypoints from other app's storage BRouter tries to write the calculated tracks to the app storage. Depending on the Android version this won't work. BRouter can be configured to write tracks to a different directory by creating a brouter.redirect file which contains a single line with the absolute path to the folder where the tracks should be written.

• For LocusMap brouter.redirect has to be located in Locus/mapItems
• For OruxMaps brouter.redirect has to be located in oruxmaps/tracklogs
• For OsmAnd brouter.redirect has to be located in osmand/tracks

Using nogo-areas

There's a special naming-convention to specify nogo-areas:

nogo[radius] [name] defines a nogo-area, where radius (in Meter) is optional and defaults to 20m, and the name is also optional. So nogo, nogo1000, nogo roadblock, nogo200 badferry are all valid names for nogo-waypoints.

The effect is that BRouter searches a route that avoids the area defined by the position and the radius of the nogo-area.

Nogo-areas are used when routing via service interface and file interface.

When using the file interface you will get a nogo-dialog allowing to de-select them if nogo-waypoints are found in the waypoint-database. This de-selection can also be bound to a service mode using the Server Mode button to make it effective using the service interface as well, but initially, every nogo-area is effective in the service interface.

Nogo-areas can be used either to account for real obstacles or to enforce personal routing preferences.

Routing via file interface

The other option is using the BRouter app to calculate a route. This is the prefered option when calculating long-distance-routes that would not finish within the 60 seconds timout if calculated via the service interface.

To do this, start the BRouter app, select two or more waypoints and then start the route calculation. BRouter either reads waypoints from the import folder or tries to read waypoints from other map tools if it has the required permission. These waypoints are called Favorites in OsmAnd, POIs in Locus or Waypoints in Oruxmaps and allow to associate a location with a name.

If your waypoint database contains a from and to waypoint the waypoint selection will be skipped. BRouter also uses via1, ..., via9 as via waypoints.

If a route is calculated, it is stored as brouter0.gpx. Depending on the waypoint database and permissions BRouter stores the route in <basedir>/import/tracks or in the map tool track directory. If started once more with identical input, BRouter will store a second route broute1.gpx for the first alternative and so on.

Permission issues

If using the file interface BRouter needs to access the files from other apps. Depending on your android version, your BRouter version and location of other apps locations it will be impossible to read or write those files.

Mixed operation: timeout-free recalculations

You can combine both operation modes (service interface + file interface to become able to calculate very long distances, but make use of the advantages of the service interface as well, especially the dynamic recalculations if you get off the track, without running into the 60 seconds timeout.

To support this, BRouter can do timeout free recalculations. It works by initially calculating a track to your destination and binding it to one or more routing-modes using the Server Mode button. This way, BRouter stores a reference track in the brouter/modes subdirectory.

If afterwards a route to the exact same destination is calculated via the service interface, BRouter uses a special calculation mode that makes use of the reference track for faster processing that is guaranteed to give a result within 60 seconds. Exact same destination means withing 5m, so best use the same waypoint for re-calculating that you used for the initial calculation.

This way you can follow a long distance route via the service interface, enjoying automatic recalculations if you get off the track.