[geos-devel] Re: [GEOS] #358: Invalid output from Union (was: Exception on Union)

[GEOS]

#358: Invalid output from Union
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 Reporter:  strk        |       Owner:  geos-devel@…              
     Type:  defect      |      Status:  new                       
 Priority:  major       |   Milestone:                            
Component:  Default     |     Version:  svn-trunk                 
 Severity:  Unassigned  |    Keywords:                            
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Comment(by strk):

 Sorry, the summary was wrong, problem is not a topology exception here,
 but an invalid result. A topology exception might come up later, when
 iteratively applying the BinaryOp.

 The invalidity is a "Too few points in ring" kind. Basically when
 translated toward origin (common bits removed) the code doesn't find
 repeated points, but after re-translating up, for some reason, two points
 become the same point (precision loss, I guess?).

 If theoretically confirmed, this might mean applying common bits removal
 might not
 be a good idea from within the SnappingOverlay OP

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Ticket URL: <http://trac.osgeo.org/geos/ticket/358#comment:2>
GEOS <http://geos.refractions.net/>
GEOS (Geometry Engine - Open Source) is a C++ port of the Java Topology Suite (JTS).