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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Thanks all. I’ll try to take a look at this in next couple of days and compare it to some of the tests I have done with existing ST_ConcaveHull.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>And Paul to be honest with you, if you just want to put your code in PostGIS master (rip out the old for GEOS 3.11), would save me and I think a lot of people, a lot of hassle. Anyone who disagrees, please chime in.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>I can always test the old ST_ConcaveHull on the 3.2 branch, so having yet another branch to try out is just very time consuming.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>It’s probably not saving too many people any trouble either because most people are not running GEOS 3.11 so wouldn’t notice the difference.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>We are like at least 8 months away from a 3.3 release, so the sooner you get it in there the better.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Thanks,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Regina<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div style='border:none;border-left:solid blue 1.5pt;padding:0in 0in 0in 4.0pt'><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> postgis-devel [mailto:postgis-devel-bounces@lists.osgeo.org] <b>On Behalf Of </b>Martin Davis<br><b>Sent:</b> Tuesday, January 25, 2022 7:05 PM<br><b>To:</b> PostGIS Development Discussion <postgis-devel@lists.osgeo.org><br><b>Subject:</b> Re: [postgis-devel] ST_ConcaveHull in GEOS<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>For some more background on the (potential) new Concave Hull algorithm, see: <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><a href="https://github.com/locationtech/jts/pull/823">https://github.com/locationtech/jts/pull/823</a><o:p></o:p></p></div><div><p class=MsoNormal><a href="http://lin-ear-th-inking.blogspot.com/2022/01/concave-hulls-in-jts.html">http://lin-ear-th-inking.blogspot.com/2022/01/concave-hulls-in-jts.html</a><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Tue, Jan 25, 2022 at 2:38 PM Paul Ramsey <<a href="mailto:pramsey@cleverelephant.ca">pramsey@cleverelephant.ca</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><p class=MsoNormal>Hey all,<br>The native ST_ConcaveHull in GEOS is in GEOS main now, so I have hooked it up into PostGIS in this branch<br><br><a href="https://github.com/pramsey/postgis/tree/master-concavehull" target="_blank">https://github.com/pramsey/postgis/tree/master-concavehull</a><br><br><br>Under this function for now.<br><br>CREATE OR REPLACE FUNCTION _ST_GEOSConcaveHull(<br> geom geometry, <br> area_ratio float8,<br> allow_holes boolean DEFAULT false)<br><br>I would like to just flip the old ST_ConcaveHull out and replace it with the new one, for folks with GEOS 3.11+, but I figured an interval to look at them side by side for a while on a test branch might be appreciated. Currently the case of point inputs is worth looking at. Polygon inputs that respect the polygon are (hull doesn't cross interior of input polygon) coming down the line.<br><br>P<br>_______________________________________________<br>postgis-devel mailing list<br><a href="mailto:postgis-devel@lists.osgeo.org" target="_blank">postgis-devel@lists.osgeo.org</a><br><a href="https://lists.osgeo.org/mailman/listinfo/postgis-devel" target="_blank">https://lists.osgeo.org/mailman/listinfo/postgis-devel</a><o:p></o:p></p></blockquote></div></div></div></body></html>