[Qgis-user] ShapeTools XY to Line

[Tobias Wendorff]

Am Fr, 17.03.2017, 19:21 schrieb C Hamilton:
> How important would it be to implement other geodetic line types ie
> GEODESIC , RHUMB_LINE, and NORMAL_SECTION.
> I > had the code for Great Circle so it was easy to implement,
> but I don't know how to implement the others.

Try to implement "Vincenty's formulae". It's very easy and much more
accurate than "Great Circle":

https://en.wikipedia.org/wiki/Vincenty's_formulae

Perhaps I can give it a try. Did something equal in the past, but
without a GUI :)

"Great Circle" and "Vincenty" work with any ellipsoid. Projecting the
current CRS to WGS84 first might be faulty. To get more accurate results,
it might be better to use the current ellipsoid.