[Olena-patches] last-svn-commit-175-g9a842d1 Improve topo::skeleton::breadth_first_thinning.

* mln/topo/skeleton/breadth_first_thinning.hh (mln::topo::skeleton::breadth_first_thinning): Fix a bias in the algorithm due to a buggy predicate. Introduce a temporary psite to help the compiler. Fix the type of `output'. --- milena/ChangeLog | 10 ++++++++++ milena/mln/topo/skeleton/breadth_first_thinning.hh | 20 ++++++++++++++------ 2 files changed, 24 insertions(+), 6 deletions(-) diff --git a/milena/ChangeLog b/milena/ChangeLog index 69c050f..72cd006 100644 --- a/milena/ChangeLog +++ b/milena/ChangeLog @@ -1,3 +1,13 @@ +2010-05-04 Roland Levillain <roland(a)lrde.epita.fr> + + Improve topo::skeleton::breadth_first_thinning. + + * mln/topo/skeleton/breadth_first_thinning.hh + (mln::topo::skeleton::breadth_first_thinning): + Fix a bias in the algorithm due to a buggy predicate. + Introduce a temporary psite to help the compiler. + Fix the type of `output'. + 2010-05-11 Roland Levillain <roland(a)lrde.epita.fr> Add missing const qualifiers in iterators on complexes. diff --git a/milena/mln/topo/skeleton/breadth_first_thinning.hh b/milena/mln/topo/skeleton/breadth_first_thinning.hh index 42e1bef..8039ffb 100644 --- a/milena/mln/topo/skeleton/breadth_first_thinning.hh +++ b/milena/mln/topo/skeleton/breadth_first_thinning.hh @@ -1,4 +1,4 @@ -// Copyright (C) 2009 EPITA Research and Development Laboratory (LRDE) +// Copyright (C) 2009, 2010 EPITA Research and Development Laboratory (LRDE) // // This file is part of Olena. // @@ -90,7 +90,7 @@ namespace mln F& is_simple = exact(is_simple_); const H& constraint = exact(constraint_); - I output = duplicate(input); + mln_concrete(I) output = duplicate(input); // Attach the work image to IS_SIMPLE. is_simple.set_image(output); @@ -133,15 +133,23 @@ namespace mln /* FIXME: We compute the cell and attachment of P twice: during the call to is_simple() and within detach(). How could we reuse this elegantly, without breaking - the genericity of the skeleton algorithm? */ + the genericity of the skeleton algorithm? + Also, keep in mind that functors can maintain an + internal state and make side effects, meaning that + e.g. constraint(p) might not be constant for a + given p during the thinning. */ if (constraint(p) && is_simple(p)) { detach(p, output); - mln_niter(N) n(nbh, p); - for_all(n) + mln_niter(N) n_(nbh, p); + for_all(n_) + { + // Same remark as above regarding P and P_. + psite n = n_; if (output.domain().has(n) - && output(n) && constraint(p) && is_simple(n)) + && output(n) && constraint(n) && is_simple(n)) next_set.insert(n); + } } } set.clear(); -- 1.5.6.5