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["Sebastien Loriot (GeometryFactory)" <>]

nsoonhui wrote:
> I am referring to alpha_shape_2.h.
>
> From the 
> http://webcache.googleusercontent.com/search?q=cache:F_61Ln5_tjkJ:www.cgal.org/Manual/latest/include/CGAL/Alpha_shape_2.h+Alpha_shape_2.h+typedef+typename+Gt::Ray_2+Ray%3B&cd=1&hl=en&ct=clnk&gl=my
> definition , there is this line: 
>
>   typedef typename Gt::Ray_2 Ray;
>
>
> But from what I can see, the Ray is simply not used in anyway, is it
> possible to remove it?
>
> The reason I ask this is because without removing this line, one is simply
> not possible to compile the following code:
>
>
> struct Kernel : public CGAL::Exact_predicates_exact_constructions_kernel 
> {};
> typedef CGAL::Triangulation_euclidean_traits_xy_3<Kernel>  Gt;
> typedef CGAL::Alpha_shape_vertex_base_2<Gt> Vb;
> typedef CGAL::Alpha_shape_face_base_2<Gt>  Fb;
> typedef CGAL::Triangulation_data_structure_2&lt;Vb,Fb&gt; Tds;
> typedef CGAL::Delaunay_triangulation_2&lt;Gt,Tds&gt; Alpha_Triangulation_2;
> typedef CGAL::Alpha_shape_2<Alpha_Triangulation_2>  Alpha_shape_2;
>
> Which means I am unable to use Triangulation_euclidean_traits_xy_3 with
Also, note that the class Triangulation_euclidean_traits_xy_3 is
deprecated and CGAL::Projection_traits_xy_3<K> should be used instead.

Sebastien.

> alpha_shape_2, even though I am able to use it with
> Delaunay_triangulation_2, although the two are not really that different,
> only different by an (unused) definition.
>
>
> --
> View this message in context: 
> http://cgal-discuss.949826.n4.nabble.com/Is-Ray-typedef-really-needed-in-Alpha-Shape-2-h-tp3866348p3866348.html
> Sent from the cgal-discuss mailing list archive at Nabble.com.