[postgis-users] ST_Contains - WGS84

Markus Schaber schabi at logix-tt.com
Fri Jun 27 05:40:15 PDT 2008


Hi, Regina,

"Obe, Regina" <robe.dnd at cityofboston.gov> wrote:

> If a contains b in WGS 84 long lat space, a will contain b in any
> projection  you can project them to (and vice versa).  I think about
> these things as just wrapping rubber bands around stuff. No matter how
> you distort the shape of the rubber band, things inside it are always
> inside it.

I'm not really sure about that, it may be that the rubberbands get
mangled into curves in certain projections. And so vertexes from other
polygons might "jump" on the other side of the rubberband.


I don't know any good solution for that, whatsoever.


Regards,
Markus

-- 
Markus Schaber | Logical Tracking&Tracing International AG
Dipl. Inf.     | Software Development GIS

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