<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div class=""><div class="">Hi Markus,</div></div><div class=""><br class=""></div>On Jun 13, 2018, at 3:04 PM, Markus Nullmeier <<a href="mailto:mnullmei@ari.uni-heidelberg.de" class="">mnullmei@ari.uni-heidelberg.de</a>> wrote:<br class=""><div><blockquote type="cite" class=""><br class="Apple-interchange-newline"><div class=""><div class="">Hello list,<br class=""><br class="">On 13/06/18 20:19, Patrick Dowler wrote:<br class=""><blockquote type="cite" class="">PPS-Anyone using postgresql+pgsphere should note that winding direction<br class="">doesn't matter for spoly because that library chose the "less than half the<br class="">sphere" definition<br class=""></blockquote><br class="">As one of pgSphere's maintainers, I consider this to be a bug<br class="">in pgSphere from the beginning. The only remaining question is<br class="">when/if I, or others, will find the time to fix it, or else<br class="">somebody will find the money to directly order a fix.<br class=""><br class="">Best regards,<br class="">Markus Nullmeier<br class=""></div></div></blockquote></div><div class=""><br class=""></div>If you haven't already, I think it may be worth taking a look at the spatial primitives in Google's S2 geometry library (see <a href="http://s2geometry.io" class="">http://s2geometry.io</a>). It appears to implement spherical polygons using the "interior is on the left" rule, supports polygons that are larger than a hemisphere, and supports boolean operations on polygons, i.e. many of the hard-to-do-well things have been done.<div class=""><br class=""><div class=""><div class=""><div class="">Cheers,</div><div class="">Serge</div><div class=""><br class=""></div><div class=""><br class=""></div></div></div></div></body></html>