OGF:Fit for routing

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Achtung.svg Routing and Nominatim services for the OGF map were provided by user martinum4, who is no longer active. So although these features may continue to work in limited ways, they are not fully functional. The admin team would like to restore or replace them when we can, but this will necessitate finding someone to take charge of the project. If you have the resources, expertise, and willingness to restore and run these services, please contact admin.
Work in progress This list is incomplete. It will be expanded in the future.

On OGF you can design a route from a place "A" to a place "B" with the wayfinding tool. The green icon indicates the starting point and the red icon symbolizes the end of the route.

Given is the distance in kilometers and the time needed. Also you get a list of way-sections with the name of the street and the length of each section. For a satisfactory result your mapping should include the following information:

Names and refs

Names and coordinates of starting and ending places are determined by using Nominatim. Most of the "Unnamed Road"-Names are due to the implementation of the Route-Information-Parser, in our case this is the OGF-Mainpage. If you take a look at these different two real-world-examples. You'll see that, using the same routing-server-query, both data-users handle unnamed roads differently. One displays "Unnamed road" while the other one omits that information.

Places

If you give as start or end the name of a town or village or other place then the exact point is in the middle of the name - that means there, where the node for the place-tag is. If you think, that is the wrong place, you can move the node for the place.

Streets

If a street has no name, then in the list of way-sections you read "unnamed road". Please give all streets in your towns or a villages a name. Down to secondary roads a ref-number is helpful too. Landroads in rural areas could be named "Way to X-village".

In the most cases motorways have no name. Due to that please assign the motorway a number using the ref-tag, as an example a motorway could be tagged with ref=M 4.

Connections

Short connections between two roads (which should use the _link-type of the correspondending road, down to tertiary_link)without name too will shown as "unnamed road". Often this ways are so short, that a name is not to seen at the map. This also applies to motorway-junctions and -exits, where you could use names as "exit 45 in", "exit 45 out", "M9 to M17"

Motorway-junctions

If your motorway-junctions and -exits (tagged as highway=motorway_junction) have no name, you could use names like "A-Town North", "B-Village Interchange" or "C-Place Triangle" to get a better overview on the map.

Houses

-- will be follow --

Speed

The routing-system displays the fastest connection between two points. That must not be the shortest line, if the way over a motorway or trunk-road is faster. The different categories of streets have for the routing-system a different default-speed. Therefore it is not necessary, to set for all streets a speed limit. If a road has no given speed limit you can tag that via maxspeed=none, the router will use it's maxspeed of 130 km/h then.

highway= assumed Speed in km/h
motorway 120
motorway_link 45
trunk 85
trunk_link 40
primary 65
primary_link 30
secondary 55
secondary_link 25
tertiary 40
tertiary_link 20
unclassified 25
residential 25
living_street 10
service 15

You could also use traffic classes instead of tagging maxspeeds to every way, for more information on that contact martinum4.

Ferries

A ferry is much slower as a car on a highway, thus it is assumed with a cruising speed of only 25 km/h. So it can happen, that the found route avoids a ferry and uses a longer, landbound way. But if a ferry is faster compared to the landbound route, the router will choose the ferry.

The ferry-line must be connected with the highway network at a shared node at both sides of the ferry line as physical junction.

If the ferry-line is not named, then the ferry will appear in the list of way-sections as "unnamed road". Please give your ferry-line a name.

Missing junctions

If the given route makes strange ways aside, please check if the junctions of the streets are correct. If there is no exit at a motorway or trunk-road, the route can not use this motorway. Crossing streets in a town must have a node at the crossing point. As in reality a physical connection is necessary. A common mistake is to map only one Motorway and not realizing that some editors set motorways to oneway=yes.


Technical Background

For anyone interested i'll describe the routing service a little bit in the following paragraph. The Backend for the routing service is an OSRM-Server which is manually updated (but at least once a day). You can check here when the last update was done, the starting time is also the time of the data that is being used to generate the routing information. After starting generation the OSRM-Server computes the speeds for each road that is not an routing island, meaning it is connected to more than one road or is an oneway that leads to nothing, this takes about three to four hours in total. After that the Server is restarted with the new routing information. Due to that fact, that all speeds are precomputed, answer times are relatively low because there's way less calculation every time a route is computed.

Questions

If there are any questions, please use the discussion-side.