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[Shrabani Ghosh <>]

Hi,

I assigned id to the halfedges. Like this : 

  for( Surface_mesh::Halfedge_iterator eb = surface_mesh.halfedges_begin()
     , ee = surface_mesh.halfedges_end()
     ; eb != ee
     ; ++ eb
     )
    eb->id() = index++;

But in the visitor, it does not print the original edges ids but just prints the increment numbers. How can I print in the visitor so that it shows the edge->id and I want to see the sequence of edge collapse? 

Edges collected: 23
Edges collapsed: 1
Edges collapsed: 2
Edges collapsed: 3
Edges collapsed: 4
Edges collapsed: 5
Edges collapsed: 6
Edges collapsed: 7
Edges collapsed: 8
Edges collapsed: 9
Edges non_collapsable: 1
Edges non_collapsable: 2
Edges non_collapsable: 3

Edges collected: 23
Edges processed: 12
Edges collapsed: 9

Edges not collapsed due to topological constraints: 3
Edge not collapsed due to cost computation constraints: 0
Edge not collapsed due to placement computation constraints: 0

Finished...
20 edges removed.
6 final  half edges.

These are the final halfedges ids. 
28
29
32
33
36
37

Thank You

Shrabani Ghosh

On Wed, Oct 16, 2019 at 3:10 AM Sebastien Loriot (GeometryFactory) <> wrote:

You have the information about what will be collapsed in the visitor.
You are free to assign an id to the edge if needed using a hash map
if needed.

Sebastien.

On 10/11/19 5:57 AM, Shrabani Ghosh wrote:
> Hi,
> I am working on surface_mesh_simplification.
> I am referencing here this example.
>
> https://doc.cgal.org/latest/Surface_mesh_simplification/Surface_mesh_simplification_2edge_collapse_visitor_surface_mesh_8cpp-example.html
>
> I want to keep track of the edges are collapsing for further use.
> Let's say, in my mesh, there are 10 edges.
>
> I want to use keep trace if edges 5,6,7,8 are collapsing.
> if 6 and 7 number edges are collapsed, I want to save the edge numbers.
>
> And after collapsing edges on the first iteration, the ids of the edges
> changes from the original mesh?
>
> Thank you.
> Shrabani Ghosh
>
>
>
> --
> Sent from: http://cgal-discuss.949826.n4.nabble.com/
>

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