[Olena-patches] 2580: Add a functor encoding the geometry of a complex using its 0-faces.

* mln/geom/complex_geometry.hh: New. --- milena/ChangeLog | 6 + milena/mln/geom/complex_geometry.hh | 217 +++++++++++++++++++++++++++++++++++ 2 files changed, 223 insertions(+), 0 deletions(-) create mode 100644 milena/mln/geom/complex_geometry.hh diff --git a/milena/ChangeLog b/milena/ChangeLog index 36dd95d..afe3d11 100644 --- a/milena/ChangeLog +++ b/milena/ChangeLog @@ -1,5 +1,11 @@ 2008-10-16 Roland Levillain &lt;roland(a)lrde.epita.fr&gt; + Add a functor encoding the geometry of a complex using its 0-faces. + + * mln/geom/complex_geometry.hh: New. + +2008-10-16 Roland Levillain &lt;roland(a)lrde.epita.fr&gt; + Add a multiple-site type. * mln/util/multi_site.hh: New. diff --git a/milena/mln/geom/complex_geometry.hh b/milena/mln/geom/complex_geometry.hh new file mode 100644 index 0000000..2e44ad4 --- /dev/null +++ b/milena/mln/geom/complex_geometry.hh @@ -0,0 +1,217 @@ +// Copyright (C) 2008 EPITA Research and Development Laboratory (LRDE) +// +// This file is part of the Olena Library. This library is free +// software; you can redistribute it and/or modify it under the terms +// of the GNU General Public License version 2 as published by the +// Free Software Foundation. +// +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +// General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this library; see the file COPYING. If not, write to +// the Free Software Foundation, 51 Franklin Street, Fifth Floor, +// Boston, MA 02111-1307, USA. +// +// As a special exception, you may use this file as part of a free +// software library without restriction. Specifically, if other files +// instantiate templates or use macros or inline functions from this +// file, or you compile this file and link it with other files to +// produce an executable, this file does not by itself cause the +// resulting executable to be covered by the GNU General Public +// License. +// reasons why the executable file might be covered by the GNU General +// Public License. + +#ifndef MLN_GEOM_COMPLEX_GEOMETRY_HH +# define MLN_GEOM_COMPLEX_GEOMETRY_HH + +/// \file mln/geom/complex_geometry.hh +/// \brief A functor associating geometry (location) data to the faces +/// of a complex. +/// +/// \see mln::topo::complex. + +# include <vector> +# include <set> + +# include <mln/topo/face.hh> + +# include <mln/util/multi_site.hh> +# include <mln/util/tracked_ptr.hh> + + +/* FIXME: Also provide functors where the locations are computed using + a function (useful for a complex on a regular grid/support. */ + +/* FIXME: This class could probably be turned into something more + generic, usable for other other purpose, e.g. attaching sites to + graphs. */ + +/* FIXME: Also provide another geometry type where everything is + stored even for n-face with n > 0. */ + + +namespace mln +{ + + namespace geom + { + + // Forward declaration. + namespace internal + { + template <typename P> struct complex_geometry_data; + } + + + /** \brief A functor returning the sites of the faces of a complex + where the locations of each 0-face is stored. Faces of higher + dimensions are computed. + + \arg \p D The dimension of the complex. + \arg \p P The type of the location of a 0-face. + + Locations of 0-face are usually points (hence the \p P above), + but can possibly be any (default-constructible) values. + + The functor returns a std::vector of locations: 0-faces are + singletons, 1-faces are (usually) pairs, faces of higher + dimensions are arrays of locations. + + Note that for consistency reasons w.r.t. the return type of + operator(), returned sites are always <em>arrays</em> of + locations attached to 0-faces; hence the returned singletons + (of locations) for 0-faces. */ + template <unsigned D, typename P> + class complex_geometry + { + public: + typedef P location; + typedef util::multi_site<P> site; + + public: + /// \brief Build a complex geometry object. + complex_geometry(); + + public: + /// \brief Populate the set of locations. + /// + /// Append a new location \a p. Return the index of the newly + /// created location (which should semantically match the id of + /// the corresonding 0-face in the complex). + unsigned add_location(const P& p); + + /// \brief Retrieve the site associated to \a f. + site operator()(const mln::topo::face<D>& f) const; + + private: + mln::util::tracked_ptr< internal::complex_geometry_data<P> > data_; + }; + + + namespace internal + { + /// \brief The data stored in a complex_geometry object. + /// + /// \arg \p P The type of the location of a 0-face. + template <typename P> + struct complex_geometry_data + { + util::multi_site<P> zero_faces; + }; + } + + + +# ifndef MLN_INCLUDE_ONLY + + template <unsigned D, typename P> + inline + complex_geometry<D, P>::complex_geometry() + : data_(new internal::complex_geometry_data<P>()) + { + } + + template <unsigned D, typename P> + inline + unsigned + complex_geometry<D, P>::add_location(const P& p) + { + mln_precondition(data_); + // FIXME: These two lines are not thread safe. + data_->zero_faces.push_back(p); + return data_->zero_faces.size(); + } + + template <unsigned D, typename P> + inline + util::multi_site<P> + complex_geometry<D, P>::operator()(const mln::topo::face<D>& f) const + { + mln_precondition(data_); + site s; + s.reserve(1); + if (f.n() == 0) + { + // F is a 0-face. + mln_assertion(f.face_id() < data_->zero_faces.size()); + s.push_back(data_->zero_faces[f.face_id()]); + } + else + { + // F is an n-face, with n > 0. + typedef std::vector < topo::face<D> > faces_t; + typedef std::set < topo::face<D> > faces_set_t; + + // The adjacent m-faces. + faces_t m_faces = f.lower_dim_adj_faces(); + // The set of (m-1)-face being built. + /* FIXME: This pattern is recurring in Milena---using an + std::set (or any fast associative container) to improve + the lookup speed of an std::vector; we should create a + class for this, a bit like mln::util::set, but with a + garantee on the order of insertion. */ + faces_t work_faces; + faces_set_t work_faces_set; + + // Iteratively compute the set of locations. + for (unsigned m = f.n() - 1; m > 0; --m) + { + for (typename faces_t::const_iterator g = m_faces.begin(); + g != m_faces.end(); ++g) + { + faces_t m_minus_one_faces = g->lower_dim_adj_faces(); + // Don't insert a face twice. + for (typename faces_t::const_iterator h = + m_minus_one_faces.begin(); + h != m_minus_one_faces.end(); ++h) + if (work_faces_set.find(*h) == work_faces_set.end()) + { + work_faces.push_back(*h); + work_faces_set.insert(*h); + } + } + work_faces.swap(m_faces); + work_faces.clear(); + work_faces_set.clear(); + } + for (typename faces_t::const_iterator g = m_faces.begin(); + g != m_faces.end(); ++g) + { + mln_assertion(g->face_id() < data_->zero_faces.size()); + s.push_back(data_->zero_faces[g->face_id()]); + } + } + return s; + } + +# endif // ! MLN_INCLUDE_ONLY + + } // end of mln::geom + + } // end of mln + +#endif // MLN_GEOM_COMPLEX_GEOMETRY_HH -- 1.6.0.1