santoshamb wrote:
At first I used ogr2ogr to convert my data, but eventually I started
using the .Net ProjNET library.  That is when I noticed something
interesting. When converting LineStrings, ogr2ogr and ProjNet yield
basically the same results up to 9 or so decimal places which is just
fine for accuracy.  Where I began to see a lot of differences between
the two was when I looked at the extent fields in the shapefile
header.

Ben,

To me this suggests that ProjNet may be reprojecting the extents while
ogr2ogr is reprojecting the geometries, and recomputing the extents in the
new coordinate system.  I haven't verified ... just a guess.

I do know that ogr2ogr recomputes the extents written to a shapefile based
on the geometry ... extents are not carried along through a translation.

Best regards,
--
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, [email protected]
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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