[postgis-tickets] [PostGIS] #5268: ST_ShortestLine return invalid linestring when distance of geometries is 0

[PostGIS]

#5268: ST_ShortestLine return invalid linestring when distance of geometries is 0
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  Reporter:  latot    |      Owner:  pramsey
      Type:  defect   |     Status:  new
  Priority:  medium   |  Milestone:  PostGIS 3.4.0
 Component:  postgis  |    Version:  3.3.x
Resolution:           |   Keywords:
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Comment (by latot):

 That is a good point, there is several things, first, maybe in the Paul
 Norman case, remove or make them valid is way for what he want, but is not
 all the cases, so, try to introduce new features there, with params and
 custom functions, can end with too complex features, for devs and the ones
 who writes the queries, maybe, is better just accept the CASE price.

 Due to this two reasons I think handle this from the params is not the
 way, at least to keep the flexibility and simplicity.

 Maybe for that particular case of transform them to valid from a param, is
 possible to make them, but will not solve the problem.

 I think the point is how to catalogue the data in a efficient way, and for
 every type do the proper thing, that would be the challenge,. sadly I
 don't have the enough knowledge of postgres for good ideas (when they can
 be impossible to do).

 Ideally, can create groups, a function where we can split the results in
 the types we want, split by properties, with the groups done, some way
 (that I don't know how to do it) apply something to every group. Due to
 this "function that groups and categorize" is handle from Postgis we can
 keep the efficiency.

 I think the "valid geometry" definition can be overwhelming, too technical
 math, is not bad, but some times, too hard to conceive if we want them or
 not, too easy to mislead something, or apply a bad analysis, the
 definition is good, but not for all ppl.

 Example, some times in roads we don't have the height, that causes to
 represent some roads with self intersecting, is a valid geometry (road)
 for the case? Yes. Is a valid geometry by SF? No, I want to keep them as
 invalid?, yes, make it valid and create a node will create a non-
 representative road.
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Ticket URL: <https://trac.osgeo.org/postgis/ticket/5268#comment:8>
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