[postgis-users] OpenGIS Compliance Documentation

[BladeOfLight16]

I was looking at this page today:

http://postgis.refractions.net/docs/using_postgis_dbmanagement.html#OGC_Validity

This is a wonderfully simple explanation of what constitutes validity and
simplicity with regards to geometries. However, I noted that this page
doesn't seem to address problems with POLYGONs like when the exterior ring
is self intersecting. For example, this query:

SELECT ST_IsValidDetail(ST_GeomFromText('POLYGON((0 1,1 1,1 0,-1 0,-1 -1,0
-1,0 1))'));

correctly yields

(f,Self-intersection,010100000000000000000000000000000000000000)

Maybe I'm missing something in the documentation, but I don't see anything
that directly indicates that this would be considered invalid. Maybe it's
assumed that this would not be considered a POLYGON at all since a POLYGON
must be simple? I'm not really sure. I think some kind of clarification is
in order regardless of what kind. It seems that polygon rings must adhere
to the simplicity requirements for line strings. Maybe that could be
mentioned?

Thanks for PostGIS and its documentation. Easily my favorite spatial
database thus far.
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