[geos-devel] [GEOS] #982: Postgis ST_ConcaveHull Runtime GEOS Problem?

Sun Aug 25 08:14:35 PDT 2019

#982: Postgis ST_ConcaveHull Runtime GEOS Problem?
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 Reporter:  tsw         |       Owner:  geos-devel@…
     Type:  defect      |      Status:  reopened
 Priority:  major       |   Milestone:
Component:  Default     |     Version:  3.7.0
 Severity:  Unassigned  |  Resolution:
 Keywords:              |
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Comment (by komzpa):

 So, slow part is ST_Union / GEOSUnaryUnion, unioning the attached lines
 and their hull posted below (almost-hull, but that's PostGIS side issue).
 Brokenlines may seem to require insane amount of noding, but in the actual
 call almost all of it can be skipped if some kind of shortcut like "drop
 the line if it's fully covered by polygon" is implemented.

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Ticket URL: <https://trac.osgeo.org/geos/ticket/982#comment:7>
GEOS <http://trac.osgeo.org/geos>
GEOS (Geometry Engine - Open Source) is a C++ port of the Java Topology Suite (JTS).