CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Bruce Duncan wrote:
> On Lunes 09 Agosto 2010 19:43:47 Sylvain Pion escribió:
> > Le 06/08/10 17:37, Bruce Duncan a écrit :
> > > Sylvain Pion wrote:
> > > > Le 06/08/10 14:02, Bruce Duncan a écrit :
> > > > > For one of the assertions I'm hitting, I've created what I hope is a
> > > > > small testcase. The code and the output on my machine is attached.
> > > > The assertion means that an uninitialized variable has been used.
> > > > And indeed the plane equations in the Polyhedron of CGAL needs manual
> > > > construction.  Seehttp://www.cgal.org/FAQ.html#polyhedron_normals .
> > > I have tried to modify my program to use the Traits class as shown in
> > > the example program.
> > >
> > > I am now having trouble converting this Polyhedron to a Nef_polyhedron,
> > > which I want to use for the boolean operations. Is this possible?
> > >
> > > I haven't attached the compiler output this time, as it's very long.
> > > Suffice to say it starts with "Nef_3/polyhedron_3_to_nef_3.h:218: error:
> > > 'class Vector_3' has no member named 'is_degenerate'"
> > >
> > > What am I doing wrong?
> > I am not well versed enough into the Nef polyhedron to answer.
> > I hope someone else can follow up.  In any case, I advice to send
> > as much of the error message as possible : I'm not sure it's
> > possible for anyone to see what's going wrong here.
>
> Hi,
>
> Sorry for the delay in replying.
>
> I have attached my test case and the compiler output. The code compiles if 
> line 20 is changed from Polyhedron_traits_with_normals_3 to just 
> Polyhedron_traits_3.
>
> I looked at the difference between CGAL/Polyhedron_traits_3.h and 
> CGAL/Polyhedron_traits_with_normals_3.h. This hunk seemed interesting (line 
> 32):
>
> -    typedef typename Kernel::Plane_3  Plane_3;
> +    typedef typename Kernel::Vector_3 Plane_3;
>
> I changed the code to:
>
>     typedef typename Kernel::Plane_3 Plane_3;
>     typedef typename Kernel::Vector_3 Vector_3;
>
> and it seems to compile. Is this a bug in CGAL? Perhaps the author intended 
> both Plane_3 and Vector_3 to be defined?
>
> Thanks,
> Bruce
Hello Bruce,

I had a look at the code and the problem is in my opinion in 
polyhedron_3_to_nef_3 which assumes that the type Plane defined by the 
polyhedron traits is a of type Plane<K>. I will have a closer look at it 
to find a solution.

Can you use Polyhedron_traits_3 instead?

S.

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