CGAL users discussion list

[<>]

Hi,
i think i've found what i want: a convex hull of a set of points. I got it to
work with a 2d point set. However, my points are in 3d so i was thinking of
using a xy trait class. But i don't get it to work. I always struggle with the
traits declaration... Any help is much appreciated!

struct K : public CGAL::Exact_predicates_inexact_constructions_kernel {};
typedef K::Point_3   Point;
typedef CGAL::Convex_hull_projective_xy_traits_2<Point> Traits_xy;

ifstream ch_in("surface.dat");
ofstream ch_out("hull.dat");

istream_iterator<Point>  in_start( ch_in );
istream_iterator<Point>  in_end;
ostream_iterator<Point>  out( ch_out, "\n" );

CGAL::ch_graham_andrew( in_start, in_end, out, Traits_xy);