You can have multiple resulting polygons, e.g. polygon with a hole or

multiple disconnected polygons which all are non simple. To avoid that

you need first find the right alpha value such that you have only one

polygon and possibly remove a hole from that polygon. Also you can sort

the vertices by using points with data. Assign the points an identifier

and use the edge iterator to find the correct order.

On 18/12/18 13:52, Orxan Shibliyev wrote:

> I used CGAL's alpha_shape_2 in REGULARIZED mode to get outline of set

> of points. I want to calculate area of the resultant shape. I tried to

> make a Polygon_2 from vertices obtained with

> Alpha_shape_vertices_iterator but it seems like the points are not

> ordered because is_simple for the polygon returned wrong. Segments

> obtained with Alpha_shape_edges_iterator are not ordered/connected as

> well. is_simple is important because area is ill defined without it.

>

> Can someone share his experience with finding area of polygon obtained

> with alpha_shape_2?

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