[Boost-bugs] [Boost C++ Libraries] #13494: polygon intersection fails

Subject: [Boost-bugs] [Boost C++ Libraries] #13494: polygon intersection fails
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2018-03-27 13:21:11

#13494: polygon intersection fails
-----------------------------------+----------------------------
 Reporter:  lehnert@…              |      Owner:  Barend Gehrels
     Type:  Bugs                   |     Status:  new
Milestone:  To Be Determined       |  Component:  geometry
  Version:  Boost 1.66.0           |   Severity:  Showstopper
 Keywords:  geometry intersection  |
-----------------------------------+----------------------------
 Hello,

 executing the following polygon intersection produces an empty result
 although the second operand is completely inside the first.

 Code snippet:
     using point_type = boost::geometry::model::d2::point_xy<double>;
     using polygon = boost::geometry::model::polygon<point_type>;
     using multi_polygon = boost::geometry::model::multi_polygon<polygon>;

     polygon op1, op2;
     multi_polygon result;

     boost::geometry::read_wkt("POLYGON((-1.99900000000000011
 -0.889961757413527343,-1.99900000000000011
 -1.12178395051169733,-1.89792526415373097
 -1.49900000000000011,-1.8358086947169705
 -1.49900000000000011,-1.99900000000000011 -0.889961757413527343))", op1);
     boost::geometry::read_wkt("POLYGON((-1.97591538973459313
 -1.20793688888334905,-1.92415157993614439
 -1.40112205701807624,-1.8661960316547388
 -1.38559291465704759,-1.91795984145318754
 -1.19240774652231996,-1.97591538973459313 -1.20793688888334905))", op2);
     boost::geometry::intersection(op1, op2, result);

 I could track down the problem to the intersection/touch part.
 We use the intersection code quite heavily and such a constellation can
 occur frequently in our application. (I could present several more sample
 data for this bug). Therefore I set this to showstopper.
 Also I found other entries which look quite similar.

-- 
Ticket URL: <https://svn.boost.org/trac10/ticket/13494>
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