Re: [Boost-bugs] [Boost C++ Libraries] #9873: Boost.Geometry: boost::geometry::convex_hull makes a convex polygon look concave for certain values

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #9873: Boost.Geometry: boost::geometry::convex_hull makes a convex polygon look concave for certain values
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-08-24 12:32:31

#9873: Boost.Geometry: boost::geometry::convex_hull makes a convex polygon look
concave for certain values
-------------------------+-------------------------------------------------
  Reporter:  richel@…    |      Owner:  barendgehrels
      Type:  Bugs        |     Status:  new
 Milestone:  To Be       |  Component:  geometry
  Determined             |   Severity:  Problem
   Version:  Boost       |   Keywords:
  1.55.0                 |  Boost.Geometry,boost::geometry::convex_hull,convex_hull
Resolution:              |
-------------------------+-------------------------------------------------

Comment (by Jan-Henrik Kluth <j.kluth@…>):

 I have a similar problem, so I add my case to this ticket:

 I projected a large 3D model (~200000 points) into a plane and wanted to
 compute a convex hull of those 2D points. Unfortunately
 boost::geometry::convex_hull sometimes returns a non-convex polygon.

 I dumped one example output to file and used those numbers for a second
 run of boost::geometry::convex_hull. The result stays the same. You can
 find this in the attached file, as well as a screenshot of the resulting
 wrong polygon.

 I am using Windows 7 with Visual Studio 2012 compiler and Boost 1.61.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/9873#comment:2>
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