Frank Warmerdam escribió:
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,
Hi, thanks for reply
You know I have just found out the follow information:
1.from the 1.2.0 release of PostGIS there is support for "curve"
/types/, and initial support for the ISO SQL/MM suite of spatial
database functions
2.(from the list)We made a patch to add such new geometries to PostGIS.
It implements TIN and POLYHEDRALSURFACE as described in
OGC SFS1.2 standard.
These geometries are specific MULTIPOLYGON that
describe 3D surfaces and 3D volumes.
Currently, we got the following functions to work for 3D geometries:
- asEwkb
- asEwkt
- asGml
- asSvg (2D output only)
- asX3d.
This last function enables exporting 3D geometries to the X3D format.
I also provide a patch for GEOS to implement the isValid function
for TIN and POLYHEDRALSURFACE. It checks if feature faces
are well connected and well oriented.
So after reading this I feel confused if this geometry types are really
supported or not and I think it is not clear still for me, I would like
to know if there is an official documentation but updated with the last
geometry types supported by Postgis.
Thank you very much,
karina
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