<div class="__aliyun_email_body_block"><div  style="line-height:1.7;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><div  style="clear:both;"><br ></div><div  style="clear:both;">Hi <span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;"><span  class="Apple-converted-space"> </span>Imre,</span></div><div  style="clear:both;"><span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;"><br ></span></div><div  style="clear:both;"><span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;">Thanks very much and I will try ST_AlphaShape later.</span></div><div  style="clear:both;"><span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;"><br ></span></div><div  style="clear:both;"><span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;">As an alternative way, I back port the ST_ConcaveHull implementation based on pgplsql which used for lower GEOS version. It’s working and may loss performance. </span></div><div  style="clear:both;"><span  style="caret-color:#000000;color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;font-style:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;background-color:#ffffff;text-decoration:none;float:none;display:inline;"><br ></span></div><div  style="clear:both;">Looking forward to the bug fix of the issue.</div><div  style="clear:both;"><br ></div><div  style="clear:both;">Regards,</div><div  style="clear:both;"><br ></div><div  style="clear:both;">Zhen</div><div  style="clear:both;"><br ></div><div  style="clear:both;"><br ></div><blockquote  _quote="1" style="margin-right:0;margin-top:0;margin-bottom:0;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><div  style="clear:both;">------------------------------------------------------------------</div><div  style="clear:both;">发件人：Imre Samu <pella.samu@gmail.com></div><div  style="clear:both;">发送时间：2023年8月18日(星期五) 22:39</div><div  style="clear:both;">收件人：陈振(耳辰) <erchen.cz@alibaba-inc.com>; PostGIS Users Discussion <postgis-users@lists.osgeo.org></div><div  style="clear:both;">抄　送：宋震(凡玺) <songzhen.sz@alibaba-inc.com>; 谢炯 <xiejiong.xj@alibaba-inc.com></div><div  style="clear:both;">主　题：Re: [postgis-users] PostGIS crash on ST_ConcaveHull</div><div  style="clear:both;"><br ></div><div ><div >> <span  class=" __aliyun_node_has_color" style="font-family:Helvetica,Tahoma,Arial;color:#000000;font-size:14.0px;">Any comment is welcomed.</span></div><div  class=" __aliyun_node_has_color" style="color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;margin:.0px;padding:.0px;border:.0px;outline:.0px;clear:both;"></div><br  class="gmail-Apple-interchange-newline"><div >Hi <span  class=" __aliyun_node_has_color" style="color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;">Zhen,</span><br ></div><div ><span  style="color:#000000;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;"><br ></span>I've recently tested your example with the "postgis/postgis:15-master" Docker image</div><div ><i >[GEOS version: 3.13.0dev-CAPI-1.18.0 + PostGIS version: 3.5.0dev 3.4.0rc1-21-g7faeed1d4], </i></div><div >and it appears that it crashes as well [1].</div><div ><br ></div><div >However, I found that the CGAL-based alternative ST_AlphaShape is working without issues.   [1]+[2] </div><div ><br ></div><div ><span  style="font-family:monospace;">postgres=# select ST_AlphaShape('MULTIPOINT ((113.56577197798602 22.80081530883069),(113.565723279387 22.800815316487014),(113.56571548761124 22.80081531771092),(113.56571548780202 22.800815317674463),(113.56577197817877 22.8008153088047),(113.56577197798602 22.80081530883069))'::geometry, 0.75 );</span></div><div ><span  style="font-family:monospace;"><br >                     st_alphashape                                                          <br >---------------------------------------------------<br > 010300000001000000070000006288BBAE34645C404AB48F3B02CD364065E369CF34645C4097728A3B02CD36405D9CAB9B35645C405F90693B02CD364059D1AB9B35645C40CC73693B02CD364065E369CF34645C4097728A3B02CD3640D3B<br >CBBAE34645C40348C8F3B02CD36406288BBAE34645C404AB48F3B02CD3640</span><div ><span  style="font-family:monospace;">(1 row)</span><br ></div><div ><br ></div><div ><br ></div><div >[1]<br >tested with "postgis/postgis:15-master"  <a  href="https://github.com/postgis/docker-postgis" target="_blank">https://github.com/postgis/docker-postgis</a><div ><span  style="font-family:monospace;">  POSTGIS="3.5.0dev 3.4.0rc1-21-g7faeed1d4" [EXTENSION] PGSQL="150"</span></div><div ><span  style="font-family:monospace;">  <span  style="font-weight:bold;color:#0000ff;">GEOS="3.13.0dev-CAPI-1.18.0" SFCGAL="SFCGAL 1.5.0, CGAL 5.6.1,</span> BOOST 1.74.0" PROJ="9.3.0 NETWORK_ENABLED=OFF</span></div><div ><span  style="font-family:monospace;">  URL_ENDPOINT=<a  href="https://cdn.proj.org" target="_blank">https://cdn.proj.org</a> USER_WRITABLE_DIRECTORY=/var/lib/postgresql/.local/share/proj </span></div><div ><span  style="font-family:monospace;">  DATABASE_PATH=/usr/local/share/proj/proj.db" LIBXML="2.9.10" LIBJSON="0.15" LIBPROTOBUF="1.3.3" WAGYU="0.5.0<br >  (Internal)" TOPOLOGY</span><br ><br ></div><div >[2]  <a  href="https://postgis.net/docs/en/ST_AlphaShape.html" target="_blank">https://postgis.net/docs/en/ST_AlphaShape.html</a></div><div ><i >This function effectively computes a concave hull of a geometry in a similar way to ST_ConcaveHull, but uses CGAL and a different algorithm.<br ></i></div><div ><i >Availability: 3.3.0 - requires SFCGAL >= 1.4.1.   ;  This method needs SFCGAL backend.</i><br ></div><div ><br ></div><div >Regards,</div><div >  Imre</div><div ><br ></div><div ><br ></div></div></div></div><br ><div  class="gmail_quote"><div  class="gmail_attr">耳辰 <<a  href="mailto:erchen.cz@alibaba-inc.com" target="_blank">erchen.cz@alibaba-inc.com</a>> ezt írta (időpont: 2023. aug. 18., P, 15:05):<br ></div><div  style="margin:14.0px .0px;"><div  class=" __aliyun_node_has_color" style="line-height:1.7;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;"><div  style="clear:both;"><br ></div><div  style="line-height:1.7;font-family:Tahoma,Arial,STHeiti,SimSun;font-size:14.0px;color:#000000;clear:both;"><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;">Hi guys,<br ></div><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><br ></div><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;">I met a postgis crash when tried to use ST_ConvaveHull function with a multipoint, in postgis 3.3.2 and Geos 3.11.2 :</div><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><br ></div><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span >select ST_ConcaveHull('MULTIPOINT ((113.56577197798602 22.80081530883069),(113.565723279387 22.800815316487014),(113.56571548761124 22.80081531771092),(113.56571548780202 22.800815317674463),(113.56577197817877 22.8008153088047),(113.56577197798602 22.80081530883069))', 0.75);</span></div><div  class=" __aliyun_node_has_color" style="margin:.0px;padding:.0px;border:.0px;outline:.0px;color:#000000;font-family:Helvetica,Tahoma,Arial;font-size:14.0px;font-style:normal;font-variant-ligatures:normal;font-variant-caps:normal;font-weight:400;letter-spacing:normal;text-align:start;text-indent:.0px;text-transform:none;white-space:normal;word-spacing:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span ><br ></span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;">The crash stack are listed:</span><br ></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;">#0  0x0000ffff84e02210 in geos::triangulate::tri::Tri::getIndex(geos::triangulate::tri::Tri const*) const () from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></span><div  style="clear:both;">#1  0x0000ffff84ce74c0 in geos::algorithm::hull::HullTriangulation::nextBorderTri(geos::algorithm::hull::HullTri*) ()</div><div  style="clear:both;">   from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></div><div  style="clear:both;">#2  0x0000ffff84ce7698 in geos::algorithm::hull::HullTriangulation::traceBoundary(geos::triangulate::tri::TriList<geos::algorithm::hull::HullTri>&) ()</div><div  style="clear:both;">   from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></div><div  style="clear:both;">#3  0x0000ffff84ce79d4 in geos::algorithm::hull::HullTriangulation::traceBoundaryPolygon(geos::triangulate::tri::TriList<geos::algorithm::hull::HullTri>&, geos::geom::GeometryFactory const*) ()</div><div  style="clear:both;">   from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></div><div  style="clear:both;">#4  0x0000ffff84ce1f28 in geos::algorithm::hull::ConcaveHull::toGeometry(geos::triangulate::tri::TriList<geos::algorithm::hull::HullTri>&, geos::geom::GeometryFactory const*) () from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></div><div  style="clear:both;">#5  0x0000ffff84ce29d4 in geos::algorithm::hull::ConcaveHull::getHull() ()</div><div  style="clear:both;">   from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos.so.3.11.2" target="_blank">erchen.cz/pgsql15/lib/libgeos.so.3.11.2</a></div><div  style="clear:both;">#6  0x0000ffff8e54818c in GEOSConcaveHull_r ()</div><div ><span >   from /home/<a  href="http://erchen.cz/pgsql15/lib/libgeos_c.so.1" target="_blank">erchen.cz/pgsql15/lib/libgeos_c.so.1</a></span></div><span  style="font-family:Helvetica,Tahoma,Arial;">….</span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;"><br ></span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;">It seemed that geos was failed to triangulate the multipoint and then crashed … Is this a bug of geos?</span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;"><br ></span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;">Any comment is welcomed.</span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><span  style="font-family:Helvetica,Tahoma,Arial;">Regards,</span></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;"><br ></div><div  style="margin:.0px;padding:.0px;border:.0px;outline:.0px;font-variant-ligatures:normal;text-align:start;text-indent:.0px;text-decoration-style:initial;text-decoration-color:initial;clear:both;">Zhen</div></div><div  style="line-height:20.0px;clear:both;"><br ></div></div>_______________________________________________<br >
postgis-users mailing list<br ><a  href="mailto:postgis-users@lists.osgeo.org" target="_blank">postgis-users@lists.osgeo.org</a><br ><a  href="https://lists.osgeo.org/mailman/listinfo/postgis-users" target="_blank">https://lists.osgeo.org/mailman/listinfo/postgis-users</a><br ></div></div></blockquote><div  style="line-height:20.0px;clear:both;"><br ></div></div></div>