Bug#399427: ITP: libgeo-helmerttransform-perl -- Perform transformations between geographical coordinates in different datums

[Dominic Hargreaves <dom@earth.li>]

Package: wnpp
Severity: wishlist
Owner: Dominic Hargreaves <dom@earth.li>

* Package name    : libgeo-helmerttransform-perl
  Version         : 1.11
  Upstream Author : Chris Lightfoot <chris@mysociety.org>
* URL             : http://search.cpan.org/dist/Geo-HelmertTransform/
* License         : Dual GPL/Artistic
  Programming Lang: Perl
  Description     : Perform transformations between geographical coordinates in different datums

It is usual to describe geographical points in terms of their polar
coordinates (latitude, longitude and altitude) referenced to a "datum
ellipsoid", which is used to approximate the Earth's geoid. The
latitude, longitude and altitude of a given physical point vary
depending on which datum ellipsoid is in use. Unfortunately, a number of
ellipsoids are in everyday use, and so it is often necessary to
transform geographical coordinates between different datum ellipsoids.

Two different datum ellipsoids may differ in the locations of their
centers, or in their shape; and there may be an angle between their
equatorial planes or the meridians relative to which longitude is
measured. The Helmert Transform, which this module implements, is a
linear transformation of coordinates between pairs of datum ellipsoids
in the limit of small angles of deviation between them.