Proposed features/junction details

From OpenStreetMap Wiki
Jump to navigation Jump to search
Additional junction details
Status: Proposals with undefined or invalid status (inactive)
Proposed by: Johan_C
Tagging: junction:ref=[[Tag:junction:ref=<ref>|<ref>]]
Applies to: way
Definition: Specify the ref of the junction a way belongs to
Drafted on: 2012-11-24

This proposal introduces the key junction:ref which allows to specify the reference of the junction a way belongs to.

Note: As of Nov 24th 2012 this key is already used about 6000 times according to taginfo.

Rationale

Nowadays the big suppliers of navigational devices offers a roadsign view. The key destination=* and Proposed features/Destination details offer support for a roadsign view. The key junction:ref is necessary to support the roadsign view of both exit numbers as can be seen on these signs.

A12 Den Haag junction 2 and 3 signs.jpg

Tagging

Tagging scheme
Tag Description Example
junction:ref=* Reference number. 16


Examples

Tags Description
junction:ref=2 Exit 2. This key should be used on the left way directly behind the motorway_junction node.
junction:ref=3 Exit 3. This key should be used on the right way directly behind the motorway_junction node.

Common questions

Why not stick to the ref=* in motorway_junction=*?

Good question. For normal motorway_exits the ref in the motorway_junction would be sufficient. However, there are some other reasons which make it more logical to use junction:ref.

1. Consistency in tagging. All other information to support a Roadsign view is stored in OSM ways, like maxspeed=*, lanes=*, destination=*, destination:ref=*. So why shouldn't the junction:ref info be stored in the way?

2. The current tagging of the motorway_junction node does not support the situation as shown above

Why not deprecate motorway_junction?

It's used too many times already. And it looks good in a renderer like Mapnik.

Why name it junction:ref?

It's consistent with other tagging, like destination:lanes=* and destination:ref=*

Why not use ref=*?

The ref of the motorway_link is quite often the same as the ref of the motorway, like "A 3".

Comments

Please use the Discussion page for this.

Related keys

See also