[GRASS5] Another question on the projection transform

[Glynn Clements]

zhang ji wrote:

> I have another question on the projection transform.
> Does the function in m.proj can be accessed throught
> the libgis.a? I mean does there existing the common
> API in the grass library which can be directly used 
> to do some projection transform, for example, i can
> specify what the input projection ,input lat/long and
> the output projection with the ellipsoids, and the
> function can return the output northing/easting?

Most of GRASS' projection handling is implemented via the PROJ library
(src/libes/proj), although there are some simple functions related to
the location's projection in src/libes/gis/proj[123].c.

The best place to find clues as to how to perform projections would
probably be the source code of the [rvsm].proj programs.

-- 
Glynn Clements <glynn.clements at virgin.net>