[PostGIS] #5895: Distance Calculation Issue with `ST_DistanceSphere`

[PostGIS]

#5895: Distance Calculation Issue with `ST_DistanceSphere`
------------------------------+---------------------
  Reporter:  giovannicimolin  |      Owner:  pramsey
      Type:  defect           |     Status:  new
  Priority:  medium           |  Milestone:
 Component:  postgis          |    Version:  3.4.x
Resolution:                   |   Keywords:
------------------------------+---------------------
Comment (by robe):

 I get the same results sadly even on my last compile of master branch
 so I think something is wrong.



 {{{
 POSTGIS="3.6.0dev 3.5.0-308-g935e23f3c" PGSQL="170" GEOS="3.14.0dev-
 CAPI-1.20.0" (compiled against GEOS 3.13.1) SFCGAL="SFCGAL 1.5.2, CGAL
 5.6.2, BOOST 1.86.0" PROJ="8.2.1 NETWORK_ENABLED=OFF
 URL_ENDPOINT=https://cdn.proj.org
 USER_WRITABLE_DIRECTORY=C:\Users\lr\AppData\Local/proj
 DATABASE_PATH=C:\ming64gcc81\projects\proj\rel-
 proj-8.2.1w64gcc81/share/proj/proj.db" (compiled against PROJ 8.2.1)
 GDAL="GDAL 3.9.2, released 2024/08/13" LIBXML="2.12.5" LIBJSON="0.12"
 LIBPROTOBUF="1.2.1" WAGYU="0.5.0 (Internal)" RASTER
 }}}


 The ST_DistanceSphere should return the same answer as:


 {{{
 SELECT ST_Distance(
     ST_GeomFromGeoJSON('{
         "type": "Polygon",
         "coordinates": [
             [
                 [ -93.751932270476971, 32.089230804932349 ],
                 [ -93.753830066356031, 32.089181143046332 ],
                 [ -93.753864556452115, 32.090802706180867 ],
                 [ -93.751940314782857, 32.09084654939128 ],
                 [ -93.751932270476971, 32.089230804932349 ]
             ]
         ]
     }')::geography,
     ST_GeomFromGeoJSON('{
         "type": "Point",
         "coordinates": [ 52.41828388240291, 28.68513149020453 ]
     }')::geography, false
 ) AS distance;
 }}}

 So that's good, they both agree the answer is 0 and I guess both wrong.

 I didn't think our logic relied on winding unless it started to after our
 change to use geograpiclib

 I do note that the geography intersection does come back with POINT EMPTY
 for intersecting point


 {{{
 SELECT ST_AsText(ST_Intersection(
     ST_GeomFromGeoJSON('{
         "type": "Polygon",
         "coordinates": [
             [
                 [ -93.751932270476971, 32.089230804932349 ],
                 [ -93.753830066356031, 32.089181143046332 ],
                 [ -93.753864556452115, 32.090802706180867 ],
                 [ -93.751940314782857, 32.09084654939128 ],
                 [ -93.751932270476971, 32.089230804932349 ]
             ]
         ]
     }')::geography,
     ST_GeomFromGeoJSON('{
         "type": "Point",
         "coordinates": [ 52.41828388240291, 28.68513149020453 ]
     }')::geography)
 ) AS intersection;
 }}}


 and I think the geography ST_Intersection doesn't use geographiclib but
 instead projects both geometries to some best srid and then does the
 intersection.

 @pramsey you have thoughts on this?
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5895#comment:1>
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