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List:       postgis-users
Subject:    Re: [postgis-users] Geography point to polygon st_distance for a polygon crossing the equator
From:       Paul Ramsey <pramsey () cleverelephant ! ca>
Date:       2017-02-21 14:12:03
Message-ID: CACowWR0Rrg4RnzvV1Z7bEHT43g3SEu-6-Zj-TJaP0DbsoAug4Q () mail ! gmail ! com
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That's right, we don't have a way to differentiate between great-circle
edges and loxodromes on geography (or vice versa in geometry).

​You can approximate a "square"  by densifying your east-west lines in the
places you want vertices to go, but the inter-vertex edges will still be
great circles. You can do that by densifying in geometry land and then
casting back to geography.

P.

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<div dir="ltr">That&#39;s right, we don&#39;t have a way to differentiate between \
great-circle edges and loxodromes on geography (or vice versa in \
geometry).<div><br></div>​You can approximate a &quot;square&quot;   by densifying \
your east-west lines in the places you want vertices to go, but the inter-vertex \
edges will still be great circles. You can do that by densifying in geometry land and \
then casting back to geography.<div><br></div><div>P.</div></div>


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