[Boost-bugs] [Boost C++ Libraries] #10843: polygon / voronoi: points on line segments yield errors

Subject: [Boost-bugs] [Boost C++ Libraries] #10843: polygon / voronoi: points on line segments yield errors
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-12-03 13:59:44

#10843: polygon / voronoi: points on line segments yield errors
------------------------------+----------------------
 Reporter:  maik.nijhuis@…    |      Owner:  ljsimons
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  polygon
  Version:  Boost 1.57.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+----------------------
 http://www.boost.org/doc/libs/1_57_0/libs/polygon/doc/voronoi_main.htm

 says:
 "input segments should not overlap except their endpoints"

 Their is no restriction on input *points*, though, so I conclude that
 points may lie on line segments. However, construct_voronoi fails with the
 following input:
 - One point, at (1,  0)
 - One line segment, from (0, 0) to (2, 0)

 The output has only one vertex, with invalid x and y coordinates.

 Fortunately, I can easily work around the issue:
 - Before calling construct_voronoi, I was already using intersect_segments
 for creating proper input segments. When I add the points as zero-length
 segments in the input for intersect_segments, intersect_segments will cut
 segments when there is a point at the segment.
 - Since intersect_segments discards zero-length segments, I still pass the
 points separately, as I did before.

 Could you please either update the documentation or resolve the issue
 otherwise?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/10843>
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