[josm-dev] Geometric calculations and projections

[Matthias Julius]

Paul Johnson <baloo at ursamundi.org> writes:

> Tobias Wendorff wrote:
>
>> Matthew W. S. Bell schrieb:
>>> I think the key point here that the projection used for geometry editing
>>> should be a conformal[1] one (i.e., angle preserving) like those in [2].
>>> Possibly, the projection should have an even greater restriction.
>>
>> Conformal for what distance? It's easy to do some accurate calculations
>> up to 1 km, but > 10 km or even > 100 is much more difficult, BUT: who
>> draws such big rectangles and circels in OSM?
>
> Say you want to draw Whyoming...

This is actually a good example why we might want to use Mercator for
calculating rectangles.

Matthias