[postgis-devel] [PostGIS] #555: Ability to define a geometry column as Polyhedral surface
PostGIS
trac at osgeo.org
Fri Aug 6 06:15:41 PDT 2010
#555: Ability to define a geometry column as Polyhedral surface
---------------------+------------------------------------------------------
Reporter: robe | Owner: colivier
Type: defect | Status: new
Priority: medium | Milestone: PostGIS 2.0.0
Component: postgis | Version: trunk
Keywords: |
---------------------+------------------------------------------------------
Comment(by colivier):
Regina,
A PolyhedralSurface could be 2D, 2D5 or 3D !
2D if only X,Y,(M) defined (in this case it's really close
to a multipolygon, except that we oblige all polygons to be connected)
2D5 if there's also Z defined
3D if in more each patch is connected to 2 others (and then produce a
polyhedron, so a volume)
Area work on 2D (even if your geometry is not only 2D)
On SQL/MM we are supposed to implement also in addition
ST_3DArea to deal with such a thing.
And you're definiltly right current ST_Area don'deal with Z !
There's no statement (AFAIK) to indicate what to do if
the geometry is 2D5/3D and the function is 2D only
(i.e exit on error, or silently ignore Z dimension)
For Oracle i dunno,
Only thing i've seen on papers is that they don't use the
same way to describe a volume (so not the same WKT)
--
Ticket URL: <http://trac.osgeo.org/postgis/ticket/555#comment:8>
PostGIS <http://trac.osgeo.org/postgis/>
The PostGIS Trac is used for bug, enhancement & task tracking, a user and developer wiki, and a view into the subversion code repository of PostGIS project.
More information about the postgis-devel
mailing list