[postgis-tickets] [PostGIS] #4556: st_asmvtgeom sometimes produces leaking polygons (postgis 3.0)

[PostGIS]

#4556: st_asmvtgeom sometimes produces leaking polygons (postgis 3.0)
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  Reporter:  anneb    |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 3.0.0
 Component:  postgis  |    Version:
Resolution:           |   Keywords:
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Comment (by Algunenano):

 > I believe just commenting out line:
 > lwgeom_simplify_in_place(lwgeom, res, preserve_collapsed);
 > is enough to solve the problem.

 Thanks.

 We rely on this step for 2 things:
 - Remove unnecessary points in some scenarios (for example if you have a
 straight horizontal line (0 0, 0 1, 0 4, 0 10) it'd be transformed into (0
 0, 0 10)).
 - For big lines / polygons there are some cases where it's faster to
 simplify the polygon first before doing the transformation, because the
 amount of point removed is important. This was true almost always with the
 GEOS backend, but it isn't anymore.

 The ideal situation would be to not need these calls (simplify,
 removeRepeatedPoints) at all but I'd need to look into it in more detail
 and see if we can keep the same performance and behaviour without them.

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4556#comment:3>
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