I’m splitting a highway that has a stretch of road where opposing traffic is divided, but the map only shows a single way. This highway is part of two route relations, so to avoid breaking these relations I moved the existing highway to one side of the divided region, set it to oneway=yes, and added the opposing side. I then copied all of the tags from the original highway to the new highway.
The new highway isn’t part of the route relations, though, and it wouldn’t make sense to add it before or after the existing segment. I’m not sure how route relations are used in route calculation, but if I leave it as is then the route would be impossible for someone to follow if they had to go against the one way portion. How should I handle this?
In JOSM, this wouldn’t be difficult. You need to fix each relation one after the other, while making sure the highway sections are in the correct order when you slot in the new way. At least that’s how I understand your question.
Not just public transport relations: At least in the US it is fairly common to have three relations per Interstate or US highway route: Two directional routes and a super route that holds the two directional route. For example, in my area I-5 has a “I-5 Northbound” route relation, a “I-5 Southbound” route relation and a super route relation whose two members are the north/south relations for the various states through which I-5 runs.
This seems to be pretty standarized for the US Interstate system. Less so for the US route system roads and even less for state or county routes. But I will have to say when I’ve needed to convert a section from bidirectional traffic into two one-way pieces I’ve found it a lot easier if the route was structured as multiple relations.
I’m working in JOSM but can’t figure out how to make sure the highway sections are in the correct order. Since they occupy the same part of the route, one can’t come before or after the other. Here’s a screenshot of what I’m working with:
This highway is in Florida in the US and is a part of two relations: route (“30A”, 17 members) at position 8 and route (“Scenic 30-A”, 17 members) at position 10.
Now that I see it’s at different positions in two relations with the same number of members, one route may run one way along the road and the other route may be the same stretch of road running the opposite way. I do have an error on relation “30A” that says the original segment has a wrong oneway direction, so the fix may just be to remove the original segment from the 30A relation and put the new segment in its place.
This way is at different positions in the relations because “Scenic 30-A” goes from east to west, while “30A” goes from west to east. When you cut the way at the two points where the divided part is, JOSM will automatically add the new (split) ways to the relations - they will get more members.
After adding the way for the opposite direction and the oneway attributes, as I could see in your screenshot, add the missing opposite way to both relations next to the existing oneway from the split and set the roles of both oneways to forward.
In JOSM open the edit relation box for the route you want to adjust/sort. Select/highlight in the list of members the first section of the route. (I looked at the other route relation to easily see the first one, which is CR 30A (68nodes) [id=:11,372426]. Click the “Sort the relation members” box, the members will be sorted automatically. Click the “OK” box to accept the sorting. You can repeat the process if it’s not exactly as you want.
You can also sort the relation members singularly/manually by selecting a member and move it up or down the list clicking the “Move up” or “Move down” box.
The Order of members can be reversed with “Reverse order” box.
If I understand this correctly, are you saying to have both ways in both relations, both set to “forward”? That seems counterintuitive, because if you follow a route from the beginning along each “forward” member, the end of each way should connect to the beginning of the next way.
If you approach the split from the west, and the way on the right side is the next segment of the route, then blindly following the next forward member would result in making a U-turn at the end of the split, following the segment on the other side of the split, and ending back at the beginning of the split with the next segment requiring you to double back to reach the beginning of it.
Before checking back on this thread, I just removed the original segment from the 30A relation because its oneway direction went opposite to the west-east route direction, then added the new segment to the 30A relation in the place of the original. Do both segments need to be in these relations?
Put both oneways into both relations, next to each other, like the ways 3 and 3a in the image above and add the role ‘forward’ to both oneways. On the right side of the image you see the dotted lines, where you skip a way for the desired direction.