[postgis-tickets] [PostGIS] #4711: ST_Union loses precision on complex multilinestring geometries

[PostGIS]

#4711: ST_Union loses precision on complex multilinestring geometries
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  Reporter:  dannytoone  |      Owner:  pramsey
      Type:  defect      |     Status:  new
  Priority:  medium      |  Milestone:  PostGIS 3.1.0
 Component:  postgis     |    Version:  3.0.x
Resolution:              |   Keywords:
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Comment (by mdavis):

 To follow on from what Paul has said, I tried the union using the new
 Overlay algorithm in JTS, and it works perfectly (and is pretty fast too).

 The new Overlay uses a more effective snapping approach to improve
 robustness.  It doesn't require the aggressive precision reduction that
 PostGIS/GEOS is using now.  So we're very hopeful this will solve most or
 all of these kinds of issues.

 As a side note, your synthetic data generation process seems like a great
 way to produce stress-testing datasets for overlay. This is actually
 tricky to do with synthetic data, so well done!

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Ticket URL: <https://trac.osgeo.org/postgis/ticket/4711#comment:5>
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