And relatedly, here's why Google Earth gives the wrong visual answer. http://blog.opengeo.org/2010/08/10/shape-of-a-polygon/
P. On Mon, Jun 13, 2011 at 9:47 AM, Paul Ramsey <[email protected]> wrote: > You're thinking in straight lines, not great circles. Here's what your > "box" actually looks like > > http://www.gcmap.com/mapui?P=10N+170E-10N+0E%2C%0D%0A10N+170E-5N+170E%2C%0D%0A5N+170E-5N+0E%2C%0D%0A5N+0E-10N+0E&MS=wls&DU=mi > > I can see how that could hit your Russian foot print. > > P. > > On Mon, Jun 13, 2011 at 6:54 AM, Mahesh Ghule <[email protected]> wrote: >> Hello Guys, >> After lot of head scratching I have decided to post this email. >> We have a PostGIS 1.5.1 on PostgreSQL 8.4 >> select >> ST_AsText('0105000020E6100000010000000102000000020000009FAEEE586C8C5240029CDEC5FBF94D406B44300E2EDB5140D591239D81D14C40'::geography) >> as TextFootPrint, >> >> ST_Intersects('0105000020E6100000010000000102000000020000009FAEEE586C8C5240029CDEC5FBF94D406B44300E2EDB5140D591239D81D14C40'::geography, >> ST_GeographyFromText('POLYGON((0 10,170 10,170 5,0 5,0 10))')) as >> Intersects; >> yields following result >> TextFootPrint >> | Intersects >> ------------------------------------------------------------------------------------------------------------------- >> MULTILINESTRING((74.194113 59.952996,71.424686 57.636768)) | t >> >> Which as I understand is not correct. The footprint is a line string >> somewhere over Russia and the Polygon is a band in north hemisphere just >> above equator. >> Also when I visualise the both geographies as KML in google earth I can see >> them thousands of miles apart. >> This is just one example footprint where I have tens of thousand more in my >> DB like this. >> Please help me understand what is going on? >> >> Regards, >> Mahesh >> >> _______________________________________________ >> 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
