GeographicLib

GeographicLib is a small C++ library for

geodesic and rhumb line calculations;
conversions between geographic, UTM, UPS, MGRS, geocentric, and local cartesian coordinates;
gravity (e.g., EGM2008) and geomagnetic field (e.g., WMM2020) calculations;
computations on a triaxial ellipsoid.

It is licensed under the MIT License; see LICENSE.txt.

Links:

Library documentation (latest release): https://geographiclib.sourceforge.io/C++/doc
Library documentation (all versions): https://geographiclib.sourceforge.io/C++
Change log: https://geographiclib.sourceforge.io/C++/doc/changes.html
Git repository: https://github.com/geographiclib/geographiclib
- Releases are on the release branch, and specific releases are tagged as, e.g., r1.52, r2.0, etc. This is the appropriate branch for most users of GeographicLib.
- The main branch is main and most development is done on the devel branch. These branches are for the developers of GeographicLib. Tags v1.52, v2.0, etc., are aligned with the corresponding release tags r1.52, r2.0, etc.
Source distribution: https://sourceforge.net/projects/geographiclib/files/distrib-C++
GeographicLib: https://geographiclib.sourceforge.io
GeographicLib in various languages: https://geographiclib.sourceforge.io/doc/library.html#languages
Author: Charles Karney, karney@alum.mit.edu