Saturday, March 22, 2008

MetaCRS - Coordinates & Projections

MetaCRS is a project started by Frank Warmerdam of PROJ.4 fame.

The initial basis for this project is to act as an anchor for an OSGeo Project encompassing several projections, and coordinate system related technologies.

The first technologies or libraries that are being used in this project are:

proj4js (Javascript: Rich Greenwood and Mike Adair )
libproj4 (the projection-only library maintained by Gerald Evenden)
OSGSpatialReference (GDAL coordinate system translation classes)
CS-Map (the recently open sourced library from Norm Olsen/Autodesk)

So where do non-programmers fit into this?

Frank has covered that as well and there are areas where a little geodesist like myself can contribute. If you feel you can, by all means join the mailing list.

He states on the wiki the following suggestions:
  • Common Spatial Reference System or Coordinate Reference System Names and Descriptions
  • Coordinate System (and CRS related object) dictionaries. Stuff like the EPSG dictionary.
  • Datum shift lists (towgs84), and datum grid shift files (NTv1, etc).
  • Transformations, calculations, and algorithms written in pseudocode that can be edited in different languages.
  • Descriptions of spatial reference systems that can be used by developers in different programming languages.
  • Notes on transformation from different representations of a CRS (WKT, PROJ.4, GCTP, GML,...).
  • Test suites with test points in a variety of coordinate systems and their lat/long and WGS84 equivelents).
  • Articles on spatial reference systems and translations useful for programmers interested in spatial reference system implementations. For example: Understanding The Difference Between National Vertical Datum of 1929 and the North American Datum of 1988
This will be an interesting project to be involved in.

I also hope to explain in my blog a little later, some answers to some of the suggestions above.