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[cgal-discuss] exploring Nef Polyhedra


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  • From: "" <>
  • To: "Sebastien Loriot ( via cgal-discuss Mailing List)" <>
  • Subject: [cgal-discuss] exploring Nef Polyhedra
  • Date: Thu, 7 Oct 2021 16:50:41 +0200
  • Authentication-results: mail2-smtp-roc.national.inria.fr; spf=None ; spf=Pass ; spf=None
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now exploring Nef polyhedra boolean capabilities.
As far as i understand Nef polyhedra can represent open half spaces.
Hoping that i could obtain a result in boolean subtract operation between a single face and a volume 
i modified the sample code supplied in the manual in various ways.
Last one was as below where   fill_cube_1 represents a single face and fill_cube_2 represent the piercing cube
. The result is empty.

Is this a possible operation with nef ?
Best regards
JPH

void fill_cube_1(Polyhedron& poly)
{// single plane
  std::string input =
"OFF\n\
4 1 0\n\
-1 -1 0\n\
-1 1 0\n\
1 1 0\n\
1 -1 0\n\
4  0 1 2 3";
  std::stringstream ss;
  ss << input;
  ss >> poly;
}
void fill_cube_2(Polyhedron& poly)
{
  std::string input =
"OFF\n\
8 12 0\n\
-0.5 -0.5 -0.5\n\
-0.5 0.5 -0.5\n\
0.5 0.5 -0.5\n\
0.5 -0.5 -0.5\n\
-0.5 -0.5 0.5\n\
-0.5 0.5 0.5\n\
0.5 0.5 0.5\n\
0.5 -0.5 0.5\n\
3  0 1 3\n\
3  3 1 2\n\
3  0 4 1\n\
3  1 4 5\n\
3  3 2 7\n\
3  7 2 6\n\
3  4 0 3\n\
3  7 4 3\n\
3  6 4 7\n\
3  6 5 4\n\
3  1 5 6\n\
3  2 1 6";
    std::stringstream ss;
    ss << input;
    ss >> poly;
  }





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