Simple C# class for Unity 3D to convert coordinates between WGS84 (EUREF-FIN) and ETRS-TM35FIN systems.
The official ETRS-TM35FIN definition & conversion functions: http://www.jhs-suositukset.fi/web/guest/jhs/projects/jhs154
An example Geolocation class is also provided for convenience and conversions to Unity Vector2.
Most of the code is based on the work of Olli Lammi's coordinates Python library. Other implementations referred and utilized in writing the code: