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[Kwok Jasper <>]

Thnak you for your reply.

I am using the data points in the following link

http://www.cse.ust.hk/~jamesjjx/bunny_final.pts

I have tried to insert all the points at the same time using the iterator.
The insertion process takes about 1 minute.

As you mentioned earlier that it should takes a few seconds depending on the computer used,
may I ask if 60 seconds is still reasonable? Or it should still a bit faster?

Thank you very much







> Date: Sun, 1 Feb 2009 11:07:02 +0100
> From:
> To:
> Subject: Re: [cgal-discuss] about running time related to CGAL triangiulation
>
> Kwok Jasper wrote:
> > Thank you for your reply.
> >
> > I have already optimized the compiler and made sure that it does not
> > have the debugging option selected before.
> > May I ask is it possible that it is related to the memory in my PC?
> >
> > Currently, I am using Window XP and have only less than 10 GB left in my
> > C drive.
> > May I ask if the running may be improved through increasing the memory left?
> > If it may help, how many GB shall I increase?
>
> Hi Jasper,
>
> This has nothing to do with the drive size, only with the RAM,
> but even this should not pose any problem for 362272 points.
>
> As Monique pointed out, you should either insert all points at
> the same time. If you must insert them one after the other,
> you should use the Triangulation_hierarchy_2. There is an
> example in CGAL-3.4/examples/Triangulation_2 illustrating it.
>
> Another thing is the point set itself. If it happens to be a
> grid the algorithm may be slow. We work on this.
>
> Finally, can you put the data set on a server so that we can
> try to reproduce the timings.
>
> best regards,
>
> andreas
>
> >
> > Thanks
> >
> >
> >
> > > Date: Sun, 1 Feb 2009 09:43:45 +0100
> > > From:
> > > To:
> > > Subject: Re: [cgal-discuss] about running time related to CGAL
> > triangiulation
> > >
> > > Kwok Jasper wrote:
> > > > Excuse me.
> > > >
> > > > I have tried to use the 3D Delaunay Triangulation in CGAL in Visual
> > C++
> > > > with the following declaration.
> > > >
> > > > typedef CGAL::Exact_predicates_inexact_constructions_kernel K1;
> > > > typedef CGAL::Delaunay_triangulation_3<K1> Triangulation;
> > >
> > > Also, use t.insert(begin(),end()). It uses spatial sorting, which makes
> > > the construction much faster. See the manual.
> > >
> > > > After I have set the compiler optimization in Visual C++,
> > > > when I insert 362272 points into the triangulation, it takes more than
> > > > 20 minutes
> > > > and after the insertion, when I use the iterator such as the
> > > > Finite_facets_iterator, it also takes a lot of time.< br>
> > >
> > > > May I ask if the running time is normal?
> > >
> > > no, it is not normal
> > >
> > > > Or in fact it should be faster in the normal case?
> > >
> > > It should be much faster (a few seconds, depending on your computer)
> > > Be careful to compile your code with the appropriate options (optimized
> > > and without debugging options).
> > >
> > > > Thank you very much for your attention
> > > >
> > > >
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