[geos-devel] [GEOS] #458: Polygonizer failure

GEOS geos-trac at osgeo.org
Thu Jul 14 07:30:58 EDT 2011

#458: Polygonizer failure
 Reporter:  strk        |       Owner:  geos-devel@…              
     Type:  defect      |      Status:  new                       
 Priority:  major       |   Milestone:  3.3.1                     
Component:  Default     |     Version:  3.3.0                     
 Severity:  Unassigned  |    Keywords:                            
 A simple multiline containing 3 linestrings of 2,5 and 6 vertices, all
 sharing the same endpoints (2 nodes in total in the topology)
 fail to be polygonized in floating precision, while successfully
 polygonize as 2 rings with a precision of 1e-11.

 See http://trac.osgeo.org/postgis/ticket/1115 for original report.

 In the geometry with 5 vertices, distance between first and second vertex
 and between forth and fifth vertex is 2.3283064365387e-10.

 The polygonizer returns _no_ rings.
 Dropping one of the close-by vertices (not on the topology node)
 makes the polygonizer return _1_ ring.
 Dropping both makes it succeed in returning _2_ rings as it should.

 Simplified MULTILINESTRING input follows:

Ticket URL: <http://trac.osgeo.org/geos/ticket/458>
GEOS <http://geos.refractions.net/>
GEOS (Geometry Engine - Open Source) is a C++ port of the Java Topology Suite (JTS).

More information about the geos-devel mailing list