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[morrischen2008 <>]

Hi everyone,

I am currently using Alpha Shape to construct the surface of a bunch of
points. The process is simple: the input is a bunch of points, and I get a
bunch of points as output. However, when I have indexes for the input
points, like this

input
---------------
index  location
1       (1.0, 2.0)
2       (2.1, 2.3)
3       (2.3, 1.8)
.             ...
.             ...
731   (7.1, 9.3)  
.             ...

I want to have to get, in the output points, also the indexes, like this

output
------------------
index    location
2          (2.1, 2.3)
.                 ...
.                 ...
333      (3.5, 7.8)
.                ...

However, I do not know how to obtain the indexes in outputs. Anyone here can
help me with this? I will appreciate your kind help. Below is how I obtain
the output points.

First, use the constructor

Alpha_shape_2 A(input.begin(), input.end(), FT(0.0001));

, while "input" is  a "list<Point_2>".

The output I can obtain from "A" is a bunch of points, by using the
iterators (I know I can also get a bunch of "Segment_2 as outputs as well"),
like this

for(Alpha_shape_vertices_iterator it =  A.alpha_shape_vertices_begin();
      it != A.alpha_shape_vertices_end();
      ++it) {
    Vertex_handle vh = *it;
    Point_2 p(vh->point().x(), vh->point().y());
    output.push_back(p);
}

, while "output" is a "vector<Point_2>".



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