[OSM-talk] Mapping everything as areas

[Michal Migurski]

On Nov 29, 2009, at 5:01 PM, Roy Wallace wrote:

>> From the point of view of a map, a road really
>> is a line...that happens to have some width and shape. Mapping it as
>> an area makes it primarily a chunk of asphalt...that you happen to be
>> able to drive along to get somewhere.
>
> Hmm...I think these are *both* valid interpretations of a road. I
> don't think it's a strong argument against mapping areas explicitly.

I think it's a strong argument for scale-dependent mapping of areas  
vs. ways. Both are valid interpretations, but not on the same view of  
a map. I think having a variety of data sets would help here.


>> The ideal situation would probably be to have users be able to enter
>> either ways or areas, and have the server software understand the
>> relationship between them, and convert between them.
>
> Agreed. The issue remains of whether the server should convert
> everything to 1) "split ways with width tags, implying linear
> interpolation between segments with different widths" or 2) "a way and
> an area, possibly linked with a relation". I prefer the second, as it
> more clearly encapsulates the two aspects of a road that you have
> pointed out above: 1) a line you drive along and 2) a chunk of
> asphalt.

This muddles too many needs into a single data set, and the idea of  
the server converting things could introduce a lot of problems. I  
agree that the road can be two things, but I don't think it can be  
those two things at once.

-mike.

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michal migurski- mike at stamen.com
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