[Gdal-dev] OGC Spec getExteriorRing() for a Polygon

Frank Warmerdam warmerdam at pobox.com
Tue Jul 20 18:08:02 EDT 2004


Chapman, Martin wrote:
> Frank,
>  
> The OGC Spec says that the Polygon method getExteriorRing() should 
> return a LineString.  Just out of curiosity, why do you return a 
> LinearRing from your implementation OGRPolygon::getExteriorRing()?  It 
> would make sense to me that the spec is wrong and what you want is 
> always a ring.  Do you think the OGC spec is wrong.  The following is 
> from the spec:

Martin,

Since a linearring is a subclass of linestring, a linearring is technically
a linestring.  I don't know why the Simple Features for SQL specifies
line string.  It seems kind of brain dead, and not something I'm going to
change OGR to adhere to.

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




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