Bicycle turn left issues

Open Source Routing Engine
#1

In bicycle mode, Graphhopper sometimes suggests turning left outside of a X-crossing, through a street/road, in spots without a traffic light.

For instance (going West to East):

example-fix
example-fix1920×975 165 KB

Here in blue, I have to wait and cross the traffic on Østrigsgade to be able to enter Weimargade, which can take a while and can be dangerous.

Instead, the example in red is safer and possibly quicker.

The rule could be something like: on bicycle, avoid crossing a street leftwards (for drive on the right countries) if there’s no traffic light.

Note that OSRM and Valhalla do the same, and I’m opening tickets there as well.

#2

Yes, this is an ugly limitation of the core engine.

There are basically two issues why we currently cannot implement this:

  1. we don’t know the cost of each turn, there is a prototype for this here.
  2. we don’t know that there are traffic lights, this will be enabled through this PR.
#3

Thanks for your answer! In understand. But good to know that there’s some stuff in the works that might eventually enable to improve this :slight_smile: Looking forward to see how this evolves in the future.