[geos-devel] [GEOS] #980: GEOSBuffer emits invalid buffering a collection

[GEOS]

#980: GEOSBuffer emits invalid buffering a collection
------------------------+---------------------------
 Reporter:  komzpa      |       Owner:  geos-devel@…
     Type:  defect      |      Status:  new
 Priority:  major       |   Milestone:
Component:  Default     |     Version:  3.7.0
 Severity:  Unassigned  |  Resolution:
 Keywords:              |
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Comment (by mdavis):

 Confirmed that JTS `buffer(0)` exhibits the same issue.  It produces an
 invalid output on both geometries above (of which the first is a subset of
 the second).

 This is almost certainly due to a noding robustness failure, in an area
 with several very close high precision vertices:
 {{{
 A
 []  POLYGON(108)
 Ring-CW  Vert[0 11]  POINT ( -7885150.676182368 5282400.906109639 )
 Ring-CW  Vert[0 12]  POINT ( -7885150.676182364 5282400.90610964 )
 Ring-CW  Vert[0 13]  POINT ( -7885150.676182369 5282400.906109639 )
 }}}

 Some light precision reduction might solve this problem, in this case.

-- 
Ticket URL: <https://trac.osgeo.org/geos/ticket/980#comment:2>
GEOS <http://trac.osgeo.org/geos>
GEOS (Geometry Engine - Open Source) is a C++ port of the Java Topology Suite (JTS).