Miniproj

This crate implements geographic coordinate projections between projected coordinate systems and their underlying geographic coordinate systems, for projected coordinate reference systems defined by the European Petroleum Survey Group Geodesy. It was originally developped at the GEOMAR Helmholtz Centre for Ocean Research as part of the Digital Earth Project, and continues to provide reprojection functionality to the Digital Earth Viewer.

The projections are implemented according to the Guidance Notes, with all "dynamically uniform" local variables calculated at compile time. The projections are then stored in a static PHFMap for quick access at runtime. Code generation is split out into the miniproj-epsg-registry crate, while the operations themselves are implemented in miniproj-ops.

Miniproj is not related to or derived from Proj.

Scope

Usage example

// Get the WGS84 UTM zone 32N projection
use miniproj::{get_projection, Projection};
let projection = get_projection(32632).expect("Coordinate projection not implemented");

// Coordinates of the office where this crate was written in UTM:
let (easting, northing) = (576935.86f64, 6020593.46f64);

// To get the latitude and longitude, use the Projection::to_deg method.
// Note that the order of the returned tuple is not alphabetical, but instead
// follows the axis order (X for Longitude, Y for Latitude)
let (lon, lat) = projection.to_deg(easting, northing);

assert!((lon - 10.183034) < 0.000001);
assert!((lat - 54.327389) < 0.000001);

Limitations

Miniproj is still under development and missing some important functionality. If you are looking for a refined, proven library, check out PROJ.

Changelog

0.5.0

• Added Lambert Conic Conformal (1SP) (233 defined CRS)
• Cleared up some terminology

0.4.0

• Added Popular Visualisation Pseudo-Mercator (1 defined CRS). This method might be the most popular, as it is the map projection used by Google, OpenStreetMap etc.

0.3.0

• Added Lambert Conic Conformal (2SP) (950 defined CRS)
• Fixed some major bugs in Polar Stereographic A

0.2.0

• Added Polar Stereographic Method A (10 defined CRS)

0.1.1

• Initial release

License

As many of the other components of the Digital Earth Viewer, Miniproj is licensed under EUPL v1.2, which is a copyleft license similar and compatible to GPLv2 and available in 23 languages. This license does not apply to the projections themselves. The database files are extracts from the EPSG Geodetic Parameter Registry and redistributed under their own Terms of Use.