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["Sebastien Loriot (GeometryFactory)" <>]

Sorry for the late answer,

I am working on a issue I though was similar to your
but one problem I have with correct.off and error.off is
that if I call the Polyhedron_3 method is_valid(true,4), then
it tells me that the polyhedron is not valid.

If I try loading the Nef_polyhedron using the function
OFF_to_nef_3, then the Nef_polyhedron I have is open and
so the minkowski sum cannot be done.

S.


johnzjq wrote:
> Dear Sebastien,
>
> I apologize that I have to open a new thread for minkowski_sum_3.
>
> The attached two models are nearly identical, in which the model
> "correct.off"  is produced by the translation and rotation of model
> "error.off". The model "cube.off" is the element object.
> http://cgal-discuss.949826.n4.nabble.com/file/n3432805/correct.off
> correct.off 
> http://cgal-discuss.949826.n4.nabble.com/file/n3432805/error.off error.off 
> http://cgal-discuss.949826.n4.nabble.com/file/n3432805/cube.off cube.off 
>
> The assertion is as follows:
> File: c:\Program File (x86)\CGAL-3.7\include\CGAL/Nef_3/SNC_decorator.h
> Line: 368
> Explanation: it is not possible to decide which one is a visible facet (if
> any)
>
> Code that produces assertion is attached as follows:
> #include <CGAL/Cartesian.h>
> #include <CGAL/Polyhedron_3.h>
> #include <CGAL/IO/Polyhedron_iostream.h>
> #include <CGAL/Nef_polyhedron_3.h>
> #include 
>
> typedef CGAL::Simple_cartesian kernal;
> typedef CGAL::Nef_polyhedron_3 Nef_polyhedron_3;
> typedef CGAL::Polyhedron_3 Polyhedron_3;
>
> #define INPUT_PATH "d:\\error.off"
> #define ELEMENT_PATH "d:\\cube.off"
> #define OUTPUT_PATH "d:\\output.off"
> int main(int argc, char **argv) 
> { 
>       Polyhedron_3 model, cube;
>       std::fstream file1,file2;
>       file1.open(INPUT_PATH);
>       file2.open(ELEMENT_PATH);
>       if (!file1.is_open()&&!file2.is_open())
>       {
>         return;
>       }
>       file1>>model;
>       file2>>cube;
>       file1.close();
>       file2.close();
>       //
>       if (model.is_closed()&&cube.is_closed())
>       {
>         Nef_polyhedron_3 nefmodel1(model);
>         Nef_polyhedron_3 nefmodel2(cube);
>         nefmodel1= CGAL::minkowski_sum_3(nefmodel1,nefmodel2);
>                //
>                if(nmodel1.is_simple())
>                {
>                       nefmodel1.convert_to_polyhedron(model);
>                       file1.open(OUTPUT_PATH, std::ios::out);
>                       if(file1.is_open())
>                       {
>                              
> file1<<std::fixed<<std::setprecision(6)<<model;
>                               file1.close();
>                        }
>       }
>       //
>       return 0; 
> } 
>
> It would be appreciated if you could do some investigation of this problem.
>
> Thanks very much.
>
> John
>
> --
> View this message in context: 
> http://cgal-discuss.949826.n4.nabble.com/Assertion-of-Minkowski-sum-3-tp3432805p3432805.html
> Sent from the cgal-discuss mailing list archive at Nabble.com.