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[Ophir Setter <>]

I don't see missing polylines.
You probably use the functions correctly, but I can't be sure from these few lines of code.

On Mon, Jul 5, 2010 at 2:46 AM, Richard Procter <> wrote:

Hi there,

I am having some difficulties with Arrangement_2.

Here's the problem: some of the input polylines are missing edges in the arrangement (e.g. the top right of the diagram in the attached PDF).

As I am new to CGAL, I'm unsure whether it is expected behaviour or whether I am simply misusing the class somehow.

Can someone confirm that it shouldn't be doing what I'm seeing? Are there any gotchas I should know about in the way I'm using it?

many thanks,
Richard.



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My type definitions are as follows:

   typedef CGAL::Exact_predicates_exact_constructions_kernel Kernel;
   typedef Kernel::FT Number_Type;

   typedef CGAL::Arr_segment_traits_2<Kernel> Segment_Traits_2;
   typedef CGAL::Arr_polyline_traits_2<Segment_Traits_2> Traits_2;

   typedef Traits_2::Point_2                  Point_2;
   typedef Traits_2::Curve_2                  Polyline_2;

   typedef CGAL::Arrangement_2<Traits_2>      Arrangement_2;
   typedef CGAL::Polygon_2<Kernel>            Polygon_2;

I create polylines and insert them into the arrangement as follows:

   std::list<Point_2> points;
   double x, y;
   [...]
   points.push_back(Point_2(Number_Type(x), Number_Type(y)));
   [...]
   CGAL::insert(*self->arrangement, Polyline_2(points.begin(), points.end()));

CGAL version is 3.6 on Debian Linux (Lenny) installed from ftp.mpi-sb.mpg.de
Code (it is part of a python module) is compiled by gcc 4.3.2 via:

g++ -O3 -D_REENTRANT -frounding-math -Wall -fPIC -I/usr/include/python2.5 -c arrangementmodule.cc -o arrangementmodule.o

g++ -shared arrangementmodule.o  -rdynamic -lCGAL_Core -lCGAL -lgmpxx -lmpfr -lgmp -lboost_thread-mt -o arrangement.so