[OSM-talk] Mapping streets as areas - can I do it now?

Tobias Knerr osm at tobias-knerr.de
Mon Feb 22 20:11:38 GMT 2010

Anthony wrote:
> What about http://wiki.openstreetmap.org/wiki/Key:area ?

That key doesn't describe the area covered by a road that is linear in
character - whenever a road could intuitively described as something
that goes "from here to there", area=yes likely isn't the right tag to
use. Lines/cerbs/etc. are often obvious physical hints for linear
character, but they don't need to be present for a road to be "linear".

highway=* + area=yes is for plazas and the like: Features that don't
have a concept of "direction". Instead, you can freely move from any
point of the area to every other point (and are likely to use that
ability to a certain degree).

> http://www.openstreetmap.org/?lat=28.077444&lon=-82.548096&zoom=18&layers=B000FTF

To me, these look like perfectly normal roads that should be primarily
mapped as ways.

If you want practical arguments: Way representation is more useful for
- rendering street names (visible in your example)
- supporting different zoom levels (also visible in your example)
- routing
- rendering at non-natural widths: a rendering might choose to determine
road widths according to, say, importance, or traffic density, or
whatever, which is hard to do if roads aren't represented as ways
- rendering with additional features along the road, say, lines for
cycle lanes, or dots for street lighting (with areas, "along" doesn't
quite exist)
- anything that has directional information, such as oneway roads

Of course, road area mapping still serves a purpose (primarily
high-detail, low-abstraction rendering). But detailed information like
that should be mapped *in addition* to ways, maybe similar to
waterway=riverbank. I don't think that there is an established tag, but
any tag that /isn't/ highway=* (or anything else already in use) should

Tobias Knerr

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