[postgis-tickets] [PostGIS] #4951: Geometries returning zero area with PostGIS 3.1.2

[PostGIS]

#4951: Geometries returning zero area with PostGIS 3.1.2
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  Reporter:  mboeringa  |      Owner:  pramsey
      Type:  defect     |     Status:  closed
  Priority:  medium     |  Milestone:  PostGIS 3.1.3
 Component:  postgis    |    Version:  3.1.x
Resolution:  invalid    |   Keywords:
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Comment (by mboeringa):

 Hi Paul,

 Nice answer, although it is always a bit difficult to wrap my head around
 such a description and mentally visualize what happens. Putting the
 examples in the online WKT renderer, helped though.

 So, due to the particular and a bit unfortunate peculiar nature of these
 polygons, combined with calculating the "convex hull", you end up with a
 dimensional collapse... so, yes, that explains zero area well.

 I must admit that between active code development, and multiple long
 running import and process sessions on global planet data, it is difficult
 for me to 100% garantuee I processed these geometries before (e.g. I also
 recently tested Facebook's Daylight distribution, but Facebook may have
 dropped these geometries from their distribution, IRDK).

 Nonetheless, if you have a possibility to easily test this in previous
 version, it might be worthwhile to test the result in at least on older
 version of PostGIS before closing the issue.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4951#comment:2>
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