Does the routing engine imply that highway=trunk is oneway?

[benedetto]

Consider a route between Trelleborg (Sweden) and Rostock (Germany). There is a ferry route between the two cities and from Trelleborg to Rostock the routing engine takes this ferry as intended: http://osrm.at/9v8

However, if I reverse the route, (http://osrm.at/9va) it suddenly sends me over a huge detour, which includes about 3 additional hours of driving and two ferry crossings. This is doubly suspicious as from Sassnitz, where the first ferry of the detour would leave (http://osm.org/go/0NOd0zR1-?m=), there is another direct ferry line to leave directly towards Trelleborg. Instead, the routing engine takes another hop over an Island to reach Sweden in Ystad and arrive at Trelleborg via a one hour drive.

As the ferry haven of Trelleborg (http://osm.org/go/0NZyiErH?m=) seems flawed to arrive at, I took a closer look at it and appears that the ferry terminals are directly connected via highway=trunk roads. The parts directly at the terminals don't have a oneway=yes tag, therefore they should be accessible in both directions but it seems as if the routing engine implicitly treats them as if they were oneway roads.

[emiltin]

No, only highway, highway_links and roundabouts are considered oneways by default. See https://github.com/Project-OSRM/osrm-backend/blob/master/profiles/car.lua#L249

[benedetto]

Ok, then something else must go wrong here, as other routing software (http://mapq.st/4-dnlBXqF5) gets that correctly.

The weirdest point is, if I place some intermediate destination right at the ferry terminal in Rostock, the routing takes the huge detour route to Trelleborg, goes back to Rostock by ferry and finally reaches Trelleborg by taking the detour route to Trelleborg a second time: http://osrm.at/9vz

[DennisOSRM]

It seems that the duration information for the ferry connection is broken. The travel time is way too low.

[benedetto]

Yepp, but with all the connections it seems to take into account only the time that is spent driving on land, but not the ferry times.

[DennisOSRM]

For some reason that I haven't fully understood yet, the travel time in one direction is not correctly deduced. Instead of 6 hours and 15 minutes, it takes it as 6 minutes and 15 seconds.

Waiting for the next data update to complete before diving more into this.

[DennisOSRM]

Bug has been identified in the code. Working on a fix now.