[PostGIS] #5962: Inconsistent results in multipoint clipping

[PostGIS]

#5962: Inconsistent results in multipoint clipping
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  Reporter:  bradh    |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  low      |  Milestone:  PostGIS 3.5.4
 Component:  postgis  |    Version:  3.4.x
Resolution:           |   Keywords:
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Comment (by pramsey):

 OK, this is a "representation-of-5-as-double" kind of issue, combined with
 a design decision in GEOS ClipByRect. ClipByRect assumes that points on
 the boundary should be discarded. The variability in the result seems to
 be a "representation-of-5-as-double" issue. There is an existing test that
 checks
 {{{
 /// Point on boundary
 template<>
 template<>
 void object::test<3>()
 {
     checkClipByRect(
         "POINT(15 10)",
         10, 10, 20, 20,
         "POINT EMPTY"
         );
 }
 }}}
 So, I can fix this problem in general by allowing boundary points to be
 part of the clip result, but only by changing existing behaviour. This
 would be more consistent than the current tests, which are being confused
 by cases that are boundary issues (the rectangle boundary checker is very
 complex). I wish this was just a bug.
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5962#comment:3>
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