[josm-dev] Geometric calculations and projections

[Matthew W. S. Bell]

On Mon, 2009-12-07 at 23:22 -0500, Matthias Julius wrote:
> IMHO, all those calculations should ideally be done using great
> circles. For most practical purposes using linear approximation with
> latlon directly is probably good enough for most practical
> purposes. Using Mercator for this might give better results.

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.

Matthew W.S. Bell

[1] http://en.wikipedia.org/wiki/Conformal_mapping
[2] http://www.progonos.com/furuti/MapProj/Dither/ProjConf/projConf.html
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