|Destination signs at or before intersections|
|Tools for this tag|
This relation allows information about destination signs at crossroads to be entered into OSM. When using a routing software as navigational aid, it is very helpful to be shown the signs to follow. E.g. instead of just saying "Turn left in 200m" a routing software also could say "Follow the sign to Österstad".
Note: The originally intended purpose is rendering on navigators (like this - in the next intersection follow the sign "E4 Malmö") or in turn-by-turn descriptions when following an already made route - in the original intent this is not for aiding the creation of routes.
|type||destination_sign||destination_sign||The type of relation.|
|destination||a name||ÖSTERSTAD||The destination as it says on the sign. Distance not included.|
|distance||a number km or mi||16 km||The distance reported on the sign (Optional)|
|time||hh:mm||3:15||The time reported on the sign/guidepost (Optional and for trekking)|
|colour:back||a colour||blue||The background colour of the sign. (Optional)|
|colour:text||a colour||white||The text colour of the sign. (Optional)|
|colour:arrow||a colour||white||The border/arrow colour of the sign. (Optional)|
For signs pointing to a feature use the normal tag(s) for that feature, for example a sign having a hospital icon and no name can simply be tagged type=destination_sign + amenity=hospital. Other relevant keys are ref= and aeroway=aerodrome.
For signs with multiple destinations multiple relations should be created.
Colours should default to some (preferably national standard) presets if omitted. This is handled by the routing/map showing software. Since shades of yellow are probably not interesting I don't see a need to specify an RGB-colour. Colours could (should?) be choosed from a set list e.g. black, white, red, blue, green, brown, and yellow.
Notes to makers of routing software
Once again: the originally intended purpose is rendering on navigators (like this - in the next intersection follow the sign "E4 Malmö") or in turn-by-turn descriptions when following an already made route - in the original intent this is not for aiding the creation of routes.
- Check for destination_sign-relations along the route (which is already made and we are about to follow).
- Keep all relations where the route passes the sign member and then the intersection member (if specified) of the same relation.
- Remove all relations that have from member(s) but no from member is being passed through by the route.
- If necessary (e.g. on devices with small screens) remove relations (in a smart way) so there is no more than one relation shown in each intersection.
- A good routing software would look ahead and see what destinations are shown further down the road and minimize the number of different destinations shown. One of the better ways to reduce signs is to follow signs with the same destination for as long as possible. E.g. if I'm going to Timrå I should follow the sign "E 4 Sundsvall", but I could also follow the sign "Umeå" and then "Örnsköldsvik" and then "Sundsvall" and I would still be following the exact same route. It's just a little more convenient to follow the Sundsvall-sign from the beginning.
- Show to the user a sign (possibly with specified colours) with the name from the destination-tag.