CGAL users discussion list

[Mael <>]

Hello,

You can constrain edges that you do not wish to be removed, see for 
example the following example : 
https://doc.cgal.org/latest/Surface_mesh_simplification/Surface_mesh_simplification_2edge_collapse_constrain_sharp_edges_8cpp-example.html.

For your second question, a cost is assigned to an edge, not a vertex. 
But you can independently assign vertex costs to your mesh and look up 
these cost in your placement. If you are using a Surface_mesh data 
structure, you can add properties like described in the following 
example : 
https://doc.cgal.org/latest/Surface_mesh/Surface_mesh_2sm_properties_8cpp-example.html.

Best,
Mael

On 15/10/2019 11:36, tdchen wrote:
> Thank you so much MaelRL for the so detailed suggestion!
> I will try the way you guided me, but it will spend me some time.
> There is a difference on my mesh border that:
> It is composed of some(usually 4)polylines, and I have to ensure the joint
> ends not to be removed.
> So I think I have to send some extra message to the mesh as the vertex
> property.
> Is it right?
> And if 2 ends of an edge are both on the border(border edge), I want to
> collapse it to the end with lower cost.
> I think I can call the cost function in my placement function to make
> decision, can't I?
> Thank you again.
>
>
>
> --
> Sent from: http://cgal-discuss.949826.n4.nabble.com/