“…We use some algorithms proposed in [4] to deal with two technical issues related with this scheme: the first one is that we need to compute g(C n,k ) = d(C n,k , C 0 ) + w and ∇g(C n,k ), which requires the computation of the 3D distance to a curve. The second one is that after each iteration we have to reparametrize the discrete curve to preserve the condition C n,k − C n,k−1 = 1 for all n and k = 2, .., χ(C) − 1.…”