Generating turn-by-turn directions
Turn type
The turn type depends mostly on the turn angle.
turn angle ranges and message are currently based on values from the Monav permaroute branch.
8° < angle <= 45°
Turn slightly left
45° < angle <= 135°
Turn left
135° < angle <= 172°
Turn sharply left
172° < angle <= 188°
Make a U-turn
188° < angle <= 225°
Turn sharply right
225° < angle <= 315°
Turn right
315° < angle <= 352°
Turn slightly right
352° < angle <= 8°
Head straightforward
Roundabouts
Take the 1st exit
Take the 2nd exit
Take the 3rd exit
...
Take the N-th exit
Motorway
Leave the motorway
Leave the trunk
Take the ramp to the trunk
Monav
Compiling without GUI
To compile the Monav routing daemon, run this:
qmake CONFIG+=release DEFINES+=NOGUI monavroutingdaemon.pro && make
NOTE: The Monav compile guide is wrong as it uses the correct syntax is NOGUI not nogui. If nogui is used, the option does nothing and Monav still tries to compile the GUI components.
Routing data
Data from http://monav.openstreetmap.de/ have a combined size of about 45 GB and are slightly outdated (April 2011).
Monav has its own map data repository - might be a good idea to ask them for their map generation script.
Compiling the Monav preprocessor
Compiling the current repository master branch is problematic due to some weird Mapnik dependencies.