None of the systems mentioned understand geographic coordinates as having a "wrap point" at 180. They are treated as planar, naturally your polygons connect across the central meridian instead of the dateline.
The only "solution" is to force your data to respect the dateline by cutting it in half at 180/-180 P. On Sun, Mar 15, 2009 at 3:03 PM, sige <[email protected]> wrote: > > Hi > > I have a problem with polygons spanning across the meridian (180E degrees), > for example: 45 176, 46 178, 46 -178, 45 -179, 44 179, 45 176 in a circle. > I inserted those records into PostGIS using WKT and the GeomFromText > function well. However the polygons dont show up correctly on either UDig or > OpenLayers: they are cut into two parts at 180E and connected from back to > back with long horizontal lines. I an not sure if this is a problem with the > data in PostGIS or the SW for displaying the data. > > Any body has come across this problem and any ideas? > > Thanks > > Sige > -- > View this message in context: > http://www.nabble.com/problem-with-polygons-spanning-across-180E-tp22528752p22528752.html > Sent from the PostGIS - User mailing list archive at Nabble.com. > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
