[Gdal-dev] OGR Polygon question

[Frank Warmerdam]

On Wed, 16 Feb 2005 16:12:09 -0500, William Lyons
<wlyons at prologic-inc.com> wrote:
>
> Howdy List, 
> 
> Just a quick question about the capabilities of the OGR C API. 
> 
> Is it possible to differentiate between the exterior and interior rings of
> an OGRPolygon via the C API? 

William, 

Properly speaking the OGRPolygon is only supposed to have one
exterior ring, and it should be the outside.  There are likely some OGR
drivers that still return multipolygons as polygons in which case there is
no real way to determine what are exterior rings.  But the correct solution
is for the underlying driver to be fixed. 

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    | Geospatial Programmer for Rent