This is a static archive of our old OpenStreetMap Help Site. Please post any new questions and answers at community.osm.org.

Road signs: map on-site redundant signs or only the original restriction?

0

Hello, there.

I'm wondering about mapping restriction road signs: on numerous occasions, these restrictions only repeated other restrictions, clearly in order to highlight them, for example:

  1. a no-turn restriction which prevents entry in a one-way road, or
  2. a no-entry sign with a "but road management" used to highlight a private access restriction on an access road.

In such cases, should I map these restrictions as is, or should I be smart, interpret them and only map the intent behind them, letting the routing engines managing them as they want, i.e. map these examples as:

  1. only the oneway=yes road, ignoring the resulting no-turn restrictions, and
  2. mark the road as access=private

Awaiting your answers,

Regards.

asked 16 Jul '16, 08:46

Penegal's gravatar image

Penegal
631313547
accept rate: 0%


2 Answers:

3

Always map the intent of signs. Mapping the signs themselves (and particularly repeater signs) is entirely optional, but ultimately may help fellow mappers in cases where particular restrictions, such as speedlimits, change.

The community of mappers in Helsinki, Finland moved to mapping the signs and their wiki page (https://wiki.openstreetmap.org/wiki/Finland:Traffic_signs) provides some good reasons for doing so. Broadly speaking mapping signs assists in verification, and helps spot change & errors.

answered 16 Jul '16, 19:25

SK53's gravatar image

SK53 ♦
28.1k48268433
accept rate: 22%

1

I guess it comes down to why you are mapping. :)

I have seen areas where a node for each sign it placed adjacent to the highway and, amazingly, the actual information not placed on the ways where it would do routing software any good. I've never understood that as I don't see the use case (no rendering software I am aware of shows those signs and routing software only looks at ways or relations relating to ways).

For highway mapping, I personally don't map signs, I map the intent of the signs on the ways. The reason for this is I am interested in having routing software correctly get people to where they want to go. So I'll map the lane marking (for lane guidance), add maxspeed (for better routing and speed warnings while following router instructions), turn restrictions (for legal routing), destination information (for motorway exit guidance), etc. to the appropriate ways. About the only way you'll figure out where the sign was based on my mapping is because of a change in some value (e.g. maxspeed).

I do map signs along hiking trails as they are shown by at least a few renders that specialize in back country maps and they are often significant landmarks for a person to use to keep oriented.

answered 16 Jul '16, 16:18

n76's gravatar image

n76
10.8k1082172
accept rate: 17%

Source code available on GitHub .