polyhedron_iterators.h

/***************************************************************************
 *   Copyright (C) 2007 by Pablo Diaz-Gutierrez   *
 *   pablo@ics.uci.edu   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU Library General Public License as       *
 *   published by the Free Software Foundation; either version 2 of the    *
 *   License, or (at your option) any later version.                       *
 *                                                                         *
 *   This program 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 Library General Public     *
 *   License along with this program; if not, write to the                 *
 *   Free Software Foundation, Inc.,                                       *
 *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
 ***************************************************************************/

// This file is to be included in polyhedron.h, just to keep it simple and short.
// Here we declare (and implement most of) the iterators that traverse faces,
// edges and vertices of a Polyhedron.

class const_face_iterator;
class const_edge_iterator;
class const_vertex_iterator;

class face_iterator : public std::iterator<std::forward_iterator_tag, Face*>
{
        public:
                friend class const_face_iterator;
                face_iterator(const Polyhedron* p, unsigned f) : _base(p), _here(f) {}

                Face* operator*() { return _base->_faces[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const face_iterator& fi) const { return _here==fi._here && _base==fi._base; }
                bool operator!=(const face_iterator& fi) const { return !(*this == fi); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};

class const_face_iterator : public std::iterator<std::forward_iterator_tag, const Face*>
{
        public:
                const_face_iterator(const Polyhedron* p, unsigned f) : _base(p), _here(f) {}
                const_face_iterator(const face_iterator& f) : _base(f._base), _here(f._here) {}

                const Face* operator*() const { return _base->_faces[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const const_face_iterator& fi) const { return _here==fi._here && _base==fi._base; }
                bool operator!=(const const_face_iterator& fi) const { return !(*this == fi); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};

face_iterator fBegin() { return face_iterator(this, 0); }        
face_iterator fEnd() { return face_iterator(this, numFaces()); } 

const_face_iterator fBegin() const { return const_face_iterator(this, 0); }
const_face_iterator fEnd() const { return const_face_iterator(this, numFaces()); }



class edge_iterator
{
        public:
                friend class const_edge_iterator;
                edge_iterator(const Polyhedron* p, unsigned e) : _base(p), _here(e) {}

                HalfEdge* operator*() { return _base->_halfEdges[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const edge_iterator& ei) const { return _here==ei._here && _base==ei._base; }
                bool operator!=(const edge_iterator& ei) const { return !(*this == ei); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};

class const_edge_iterator
{
        public:
                const_edge_iterator(const Polyhedron* p, unsigned e) : _base(p), _here(e) {}
                const_edge_iterator(const edge_iterator& e) : _base(e._base), _here(e._here) {}

                const HalfEdge* operator*() const { return _base->_halfEdges[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const const_edge_iterator& ei) const { return _here==ei._here && _base==ei._base; }
                bool operator!=(const const_edge_iterator& ei) const { return !(*this == ei); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};
edge_iterator eBegin() { return edge_iterator(this, 0); }            
edge_iterator eEnd() { return edge_iterator(this, numHalfEdges()); } 

const_edge_iterator eBegin() const { return const_edge_iterator(this, 0); }
const_edge_iterator eEnd() const { return const_edge_iterator(this, numHalfEdges()); }


class vertex_iterator
{
        public:
                friend class const_vertex_iterator;
                vertex_iterator(const Polyhedron* p, unsigned v) : _base(p), _here(v) {}

                Vertex* operator*() { return _base->_vertices[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const vertex_iterator& vi) const { return _here==vi._here && _base==vi._base; }
                bool operator!=(const vertex_iterator& vi) const { return !(*this == vi); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};

class const_vertex_iterator
{
        public:
                const_vertex_iterator(const Polyhedron* p, unsigned v) : _base(p), _here(v) {}
                const_vertex_iterator(const vertex_iterator& v) : _base(v._base), _here(v._here) {}

                const Vertex* operator*() { return _base->_vertices[_here]; }
                void operator++() { ++_here; }
                void operator++(int) { ++_here; }
                bool operator==(const const_vertex_iterator& vi) const { return _here==vi._here && _base==vi._base; }
                bool operator!=(const const_vertex_iterator& vi) const { return !(*this == vi); }

        protected:
                const Polyhedron* _base;
                unsigned _here;
};

vertex_iterator vBegin() { return vertex_iterator(this, 0); }           
vertex_iterator vEnd() { return vertex_iterator(this, numVertices()); } 

const_vertex_iterator vBegin() const { return const_vertex_iterator(this, 0); }

const_vertex_iterator vEnd() const { return const_vertex_iterator(this, numVertices()); }

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