[postgis-users] geometry types

[Frank Warmerdam]

Karina Guardado wrote:
> Hello,
> 
> I would like to know if there is support for Surface, Curve, TIN, 
> Triangle, PolyedralSurface and LinearRing in Postgis.

Karina,

I believe that there is not.  Normally Surface, and Curve are
uninstantiatable geometry classes (they only exist to relate
particular concrete geometry types).  So there is an SQL-MM
CIRCULARSTRING, COMPOUNDCURVE, CURVEPOLYGON, MULTICURVE and
MULTISURFACE, but no general curve or surface.  This may be
of help:

   http://postgis.refractions.net/docs/ch04.html#id2591274

I do not believe there is any support for the SF 1.2 PolyhedralSurface
or TIN types.  LinearRing is also not a concrete type as I understand
it, but only exists as a conceptual name for a ring in a polygon.  But
it is not a first class object that can stand on it's own though of
course we have the LineString.

Best regards,
-- 
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I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
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