[Gdal-dev] Contour Generation

[Frank Warmerdam]

Folks,

I have implemented contour line generation from raster DEMs as part of a
contract with Applied Coherent Technology (http://www.actgate.com/) within
GDAL.  The algorithm attempts to maintain respectible performance, and to
ensure (as far as possible) that contour lines are fully "joined up".  That
is that complete contour lines are emitted as one feature assuming they are't
split by nodata pixels.

The primary entry point is GDALContourCreate():

   http://www.remotesensing.org/gdal/gdal_alg_h.html#a27

This function is called by the commandline utility gdal_contour which so far
is only built on demand (cd into gdal/apps and do "make all").

Feedback is welcome on the algorithm.

Best regards,

-- 
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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    | Geospatial Programmer for Rent