[OSM-talk] Landuse areas etc. abutting highways

"Marc Schütz" schuetzm at gmx.net
Mon Oct 5 14:16:47 BST 2009


> >  For a road, we can either choose to map it as a linear object (this is
> the common case), or we can map its geometry more exactly by using an area.
> In both cases, however, the object in our database represents the entire
> road (i.e. not only the middle line). Because in reality, there is no gap
> between the road and the areas next to it, there shouldn't be one in the
> database either.
> >
> >  In other words, we should keep the topology intact, even if we choose
> to simplify the geometry.
> 
> This would be hard to do properly render in the renderers, as they
> will render the road with non-zero width and to render things
> correctly, they should "push" the boundaries of touching landuses so
> they will touch the rendered road borders.
> 
> It is IMHO easier to learn renderers to support proper width tag and
> add that tag to the street between.
> 
> With proper micro-mapping, even the street between could be mapped as
> an area, but that could be perhaps a bit too much of detail.
> 
> But a) could be used as acceptable temporary solution until someone
> with better information (like having aerial photography) remaps it as
> b)

Yes, this is basically what I wanted to say. Leave it to the mappers whether they want to use a way or an area for a road.

But with option (b) and a linear way you would have a gap next to the road. In the case of landuse, this is not a problem in practice, but if there is a place, there you need to insert artificial ways that are not there in reality, just to get the connectivity between the two objects:
http://osm.org/go/0JUKytHID--

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