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["Sebastien Loriot (GeometryFactory)" <>]

On 01/30/2017 12:40 PM, Nicholas Mario Wardhana wrote:
> Dear Sebastien,
>
> Thank you for your reply.
>
> Regarding the number of volumes, am I correct to say that the number
> three comes from the volumes inside my cube, the one between my cube and
> infimaximal cube, and the one outside the infimaximal cube?

Yes, exactly.

Sebastien.

> Best regards,
> Nicholas
>
> On 30 January 2017 at 05:16, Sebastien Loriot (GeometryFactory)
> <
>  
> <mailto:>>
>  wrote:
>
>     The difference you observe comes from the infimaximal box [1].
>     This means that you have another cube around your cube, which explains
>     why all numbers but #volumes are doubled.
>
>     Sebastien.
>
>     [1] http://doc.cgal.org/latest/Nef_3/index.html#title2
>     <http://doc.cgal.org/latest/Nef_3/index.html#title2>
>
>
>     On 01/24/2017 08:28 PM, Nicholas Mario Wardhana wrote:
>
>         Hello,
>
>         I am creating a cube as a nef polyhedron by defining it as the
>         intersections of the negative sides of the 6 bounding planes,
>         based on
>         the following example:
>         http://doc.cgal.org/latest/Nef_3/index.html#title6
>         <http://doc.cgal.org/latest/Nef_3/index.html#title6>
>         It then checks the properties, saves the cube to a nef3 file,
>         loads it
>         again, and checks the property again
>
>         I would expect that the cube has the following properties.
>
>           * 2-manifold (is_simple() == true)
>           * The number of volumes = 2 (inside and outside the cube)
>           * The number of shells = 2 (the inside and outside boundaries)
>           * The number of facets = 6
>           * The number of half-facets = 12
>           * The number of edges = 12
>           * The number of half-edges = 24
>           * The number of vertices = 8
>
>
>         My code prints the followings.
>
>             CreateACube()
>             nefCube.is_simple() == true
>             nefCube.number_of_volumes(), expected 2, result = 3
>             GetNumberOfShells(nefCube), expected 2, result = 4
>             nefCube.number_of_facets(), expected 6, result = 12
>             nefCube.number_of_halffacets(), expected 12, result = 24
>             nefCube.number_of_edges(), expected 12, result = 24
>             nefCube.number_of_halfedges(), expected 24, result = 48
>             nefCube.number_of_vertices(), expected 8, result = 16
>
>
>
>             LoadACube()
>             nefCube.is_simple() == true
>             nefCube.number_of_volumes(), expected 2, result = 3
>             GetNumberOfShells(nefCube), expected 2, result = 4
>             nefCube.number_of_facets(), expected 6, result = 12
>             nefCube.number_of_halffacets(), expected 12, result = 24
>             nefCube.number_of_edges(), expected 12, result = 24
>             nefCube.number_of_halfedges(), expected 24, result = 48
>             nefCube.number_of_vertices(), expected 8, result = 16
>
>
>         I did not get many of the expected properties.
>
>         However, the nef3 file does state:
>
>             vertices   8
>             halfedges  24
>             facets     12
>             volumes    2
>             shalfedges 48
>             shalfloops 0
>             sfaces     16
>
>
>         and when I cross-checked the result by loading the nef3 file to the
>         polyhedron_3 demo (http://www.cgal.org/demo/4.9/polyhedron_3.zip
>         <http://www.cgal.org/demo/4.9/polyhedron_3.zip>), it
>         correctly prints the followings.
>
>             Test_ByEquation (mode: flat+edges, color: #6464ff)
>             Nef_3 polyhedron
>
>             Number of vertices: 8
>             Number of edges: 12
>             Number of facets: 6
>             number of volumes: 2
>
>             Bounding box: min (0,0,0), max (2,2,2)
>
>             File:<path omitted>/CGAL/output/Test_ByEquation.nef3
>
>
>         The minimum working code and the resulting nef3 file are
>         attached. Could
>         anyone please point out my mistakes? Thank you.
>
>         Best regards,
>         Nicholas Mario Wardhana
>
>
>
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