[Boost-bugs] [Boost C++ Libraries] #12118: Problems performing boolean operations on polygons with shared edges

Subject: [Boost-bugs] [Boost C++ Libraries] #12118: Problems performing boolean operations on polygons with shared edges
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-04-10 20:25:08

#12118: Problems performing boolean operations on polygons with shared edges
------------------------------+---------------------------
 Reporter:  ev.mipt@…         |      Owner:  barendgehrels
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  geometry
  Version:  Boost 1.60.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+---------------------------
 I have described problems with illustrations in mailing list:
 http://lists.boost.org/geometry/2016/04/3518.php


 But forgot to mention there that despite the fact that I use same data
 every program restart, boost geometry union_ makes described problems not
 in same places. So WKT representation below is slightly different from
 pictures in mailing list post.

 WKT representations:

 Current Path polygon:
 MULTIPOLYGON(((13.0894 -70.9842,12.8138 -67.5544,12.6048 -63.5792,13.5644
 -54.9161,13.8057 -43.6207,13.0006 -33.8524,9.29665 -33.2341,19.6687
 -14.4204,-5.96064 -17.1987,-14.8704 -6.9988,-22.5081 -27.9248,-22.1616
 -45.1548,-22.4244 -54.0161,-23.1383 -59.2863,-23.1831 -68.0194,-22.8694
 -72.7853,-23.0297 -72.7676,-22.8192 -73.5476,-18.6568 -73.2505,3.16642
 -75.6601,12.7528 -76.7187,13.0894 -70.9842)))

 Appended polygon:
 MULTIPOLYGON(((3.16642 -75.6601,12.7528 -76.7187,12.95 -74.6186,3.16642
 -75.6601)),((-22.8477 -78.4296,-20.9284 -78.2253,3.16642 -75.6601,-23.0297
 -72.7676,-22.8477 -78.4296)))

 Union of current path and appended polygon result:
 MULTIPOLYGON(((12.8756 -74.6265,13.0894 -70.9842,12.8138 -67.5544,12.6048
 -63.5792,13.5644 -54.9161,13.8057 -43.6207,13.0006 -33.8524,9.29665
 -33.2341,19.6687 -14.4204,-5.96064 -17.1987,-14.8704 -6.9988,-22.5081
 -27.9248,-22.1616 -45.1548,-22.4244 -54.0161,-23.1383 -59.2863,-23.1831
 -68.0194,-22.8694 -72.7853,-23.0297 -72.7676,-22.8477 -78.4296,-20.9284
 -78.2253,3.16642 -75.6601,-18.6568 -73.2505,-18.6568 -73.2505,3.16642
 -75.6601,12.7528 -76.7187,12.95 -74.6186,12.8756 -74.6265)))

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12118>
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