CGAL users discussion list

["Sebastien Loriot (GeometryFactory)" <>]

Would this be sufficient:
https://doc.cgal.org/latest/Convex_hull_3/Convex_hull_3_2extreme_indices_3_8cpp-example.html

or you need the convex hull as well?

Sebastien.

On 2/22/19 11:29 AM, Maarten Moesen wrote:
> Dear Sebastien,
> Dear CGAL community,
>
> Thank you for your answer. Indeed, it doesn't look too hard.
>
> I'm now having a similar question about convex_hull_3: what is the 
> recommended way to keep track of the vertices in the convex hull?
> For example: if I have originally a large vector or list of points, possibly 
> with some info associated with them. How can I efficiently determine which 
> points are in the convex hull? Can I access from the resulting convex 
> polyhedron the original iterator? Can I associate some info to each point?
>
> Best regards,
>
> Maarten
> -----Original Message-----
> From: 
>
>  
> <>
>  On Behalf Of Sebastien Loriot (GeometryFactory)
> Sent: Friday, 22 February, 2019 09:50
> To: 
>
> Subject: [EXTERNAL] Re: [cgal-discuss] retrieve associated information with 
> halfspaces after a halfspace intersection
>
> With the current code there is no entry in the API. However it should not be 
> not hard to do it. Indeed, looking at the 
> halfspace_intersection_with_constructions_3.h for example, you'll see that 
> when a new face is created in build_dual_polyhedron (which is building the 
> dual of the dual, i.e. the final intersection) we iterate over vertices of 
> the convex hull of the dual (one vertex = one plane) so we could add a 
> property in the API to add that information.
>
> Best regards,
>
> Sebastien.
>
> On 2/22/19 8:19 AM, Maarten Moesen wrote:
> > Dear CGAL community,
> >
> >   From a large vector of planes (halfspaces), in which each plane has
> > some information attached, I'd like to create a convex polyhedron
> > using
> >
> > CGAL::halfspace_intersection_3() and
> > halfspace_intersection_with_constructions_3().
> >
> > How can I efficiently identify in the resulting polyhedron which
> > planes where selected, so that I can efficiently retrieve the
> > information associated to each selected plane?
> >
> > Best regards,
> >
> > Maarten
> >
> > --
> >
> > Maarten Moesen, PHD
> >
> > Polymer Physicist Computational Modeling
> >
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> >
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> >
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> >
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> >
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> >
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>
> --
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