[OSGeo-Discuss] C++ library for "gridding"

[Frank Warmerdam]

Rob Agar wrote:
> hi,
> 
> I have some elevation data in the form of a list of sampled points that 
> I would like to convert into a regular grid.  Rather than writing my own 
> code for doing this, I was wondering if there is a C++ library for doing 
> this kind of transformation?  (eg does OGR do this?)
> 
> The data is comma separated longitude, latitude and elevation.
> 
> Any advice, pointers, links to tutorials etc much appreciated - I'm new 
> to GIS, and the learning curve is steep!

Rob,

There are several algorithms for this in GRASS I believe.  Search GRASS
for Kriging and inverse distance interpolators and you should find some
options.

GDAL/OGR does not include an algorithm for point interpolation, though
OpenEV does have one (simple inverse distance I think) that I have
contemplated porting to GDAL/OGR.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org