[PostGIS] #5725: Undocumented st_offsetcurve behaviour change between 3.2 and 3.3

[PostGIS]

#5725: Undocumented st_offsetcurve behaviour change between 3.2 and 3.3
-------------------------------------------------+-------------------------
 Reporter:  gbartonowenstl                       |      Owner:  pramsey
     Type:  defect                               |     Status:  new
 Priority:  medium                               |  Milestone:  PostGIS
                                                 |  3.3.7
Component:  postgis                              |    Version:  3.3.x
 Keywords:  offsetcurve, release notes,          |
  st_offsetcurve, reversing                      |
-------------------------------------------------+-------------------------
 I've read all the release notes and searched the internet generally for
 this but I cannot find anything.

 It appears that between 3.2 and 3.3, st_offsetcurve started reversing the
 curves when a negative offset was given (the documented behaviour), where
 as previously it did not.

 Reproduction SQL:

 {{{
 select
 PostGIS_Version(),
 st_startpoint(geom),
 st_startpoint(st_offsetcurve(geom, -0.1)),
  st_distance(st_startpoint(geom), st_startpoint(st_offsetcurve(geom,
 -0.1)))

 from

 (values (st_geomfromtext('LINESTRING (2302997.443737494 116854.4859950367,
 2303083.234236186 117132.01622010056)',2163))) as vals (geom)
 }}}

 One env:
 3.3 USE_GEOS=1 USE_PROJ=1 USE_STATS=1   POINT (2302997.443737494
 116854.4859950367)     POINT (2303083.3297756314 117131.98668682482)
 290.48759954576633
 Older env:
 3.2 USE_GEOS=1 USE_PROJ=1 USE_STATS=1   POINT (2302997.443737494
 116854.4859950367)     POINT (2302997.5392769394 116854.45646176096)
 0.10000000013339401

 I think this is due to a geos change: https://github.com/dr-
 jts/geos/commit/7561b50f943305b1419bd655e10e7dcad2cb9492

 I'd say this was mostly a bug in the documentation/release notes but I
 suspect it will cause subtle sadness for many
-- 
Ticket URL: <https://trac.osgeo.org/postgis/ticket/5725>
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