C/Python library to work with spherical harmonics up to almost arbitrarily high degrees

GeoFindKey - Conformal transformation

The 3D Helmert transformation is a frequently used method in geodesy to produce transformations between different Cartesian coordinate systems

EGM96 geoid computation in C++, easy to embed

Documentation for NTv2 files and a C API to access them

Simple Gauss-Krüger transformation for C

pibic

A Software GPS decoder, going from raw 1-bit ADC samples to position fix

Software for compression/restoration of RINEX observation files developed by Y. Hatanaka of GSI

This is a library of the geodesic algorithms

The program is designed for converting geodesic coordinates to Gaus-Kruger coordinates. The program allows you to input geodesic coordinates either automatically or manually and converts them to Gaus-Kruger coordinates.

A Two-Dimensional Quality Mesh Generator and Delaunay Triangulator by Jonathan Richard Shewchuk