Navigation instructions for highways

Is there a way to distinguish instructions on highways and multi-lane roads? If a route runs along a highway for quite some time, the instructions to stay on the highway vary between “Continue straight onto A7” and “Keep left onto A7”. I find especially the second one confusing, it is as if you have to change lanes - but you don’t, you only have to avoid taking the exit which you usually do by staying in your lane of travel. Keep left or Keep right to me indicates a fork of some sort - meaning I have to take action.

Similarly, when you DO have to take an exit, the only instruction is “Keep right” (without even the name of the highway). I think that is wrong, since that only tells me to stay in the right lane - it does NOT tell me to take the exit on the right. It would be very easy for someone to interpret this as staying on the highway instead of taking the exit. AFAIK OSM has exit numbers (it shows them on the map at least), so if this kind of instruction could be accompanied by an exit number or -name, it would at least make clear that you have to exit that particular road (and thus indicate to the driver to take action instead of staying in the right lane). Much more preferable would be something like “take exit” instead of “keep right”.

This may be a question of semantics, but I think this would make instruction much clearer and easier to follow. It may be too difficult to adapt the current openrouteservice, but if in the instructions an exit number could be added, that would already make things much clearer.

Dear Stefan,

thank you for reporting these issues. Could you please post some example requests? This would ease the investigation of the issues.

Best regards,
Sascha

Hi Sascha,

Sure! One of the routes that I use a lot for testing is this one:

https://classic-maps.openrouteservice.org/directions?n1=52.770813&n2=4.992767&n3=11&a=52.647953,5.058349,52.891825,4.927085&b=0&c=0&k1=en-US&k2=km

as you can see it enters the A7-highway in The Netherlands at Step 8. The there are a few steps on the highway, some of them saying “Continue straight”, some of them saying “Keep left”. Then at step 15 the Instruction says “Keep right”, which is where I’d like to see an exit number (which might be confusing actually, seeing as roundabouts can also use an exit_number - but that could be distinguished by the Instruction Type - only Instruction Types 7 & 8 can have roundabout exit numbers, although I’ve never seen Type 8: does that one actually happen?).

This one:
https://classic-maps.openrouteservice.org/directions?n1=52.50058&n2=4.916462&n3=15&a=52.647953,5.058349,52.25393,5.122012&b=0&c=0&k1=en-US&k2=km

Shows the same issue. This one actually shows another issue as well, where it leaves the highway and immediately comes back to it, which is probably shorter distancewise but most definitely not timewise, but that’s probably due to the underlying OSM data being incorrectly tagged. But here as well you can see at step 15 “Keep right”, where it would be much more informative to include either an exit number or a road name or number to go to. Step 19 is an example of a slightly better solution, where the instruction is “Keep right onto A7”, which is already more informative (although it still does not give an exit number or where your are supposed to go to - in this case it is an exit towards another highway, the A8 - but that might again be an issue with the tagging in OSM).

Hopefully these examples show you what I am trying to say, that the instructions can be confusing at certain points. Don’t hesitate to ask if you need more information, I’ll keep a close eye on this thread :slight_smile:
and of course thank you for your time, and for the outstanding work - Basically what I am doing now is just nitpicking :grin: On the whole Openrouteservice is simply awesome.

Oh, and something I just realized: This might be caused by the heading_before and heading_after angles being too different. I’m currently playing with creating little svg icons on the fly based on the heading_before and heading_after angles to include in the instructions (those are especially helpful with the roundabouts - I still need to figure out if it’s in a left-driving country or not, because in that case I need to mirror the roundabouts), and it seems that the difference is bigger than a certain tolerance when the instruction becomes “Keep right”. But I am not certain about that. It does seem to make the “Keep right” instruction clearer when it is taking an exit from a highway. Still, if that highway-exit info could be added, that would be a tremendous improvement I think.

Hi Stefan,

Thank you for the detailed description. I have created an issue on github and, therfore, will close this topic here.

Best regards,
Sascha