// Copyright (c) 2000 Max-Planck-Institute Saarbruecken (Germany). // All rights reserved. // // This file is part of CGAL (www.cgal.org). // You can redistribute it and/or modify it under the terms of the GNU // General Public License as published by the Free Software Foundation, // either version 3 of the License, or (at your option) any later version. // // Licensees holding a valid commercial license may use this file in // accordance with the commercial license agreement provided with the software. // // This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE // WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. // // $URL$ // $Id$ // // // Author(s) : Susan Hert #ifndef CGAL_CIRC_PAIR_H #define CGAL_CIRC_PAIR_H #include namespace CGAL { // // "before" always means a point between front and back in the indicated // direction // // "after" always means a point just beyond the range of [front,back] // template class Circ_pair { public: Circ_pair(BidirectionalCirculator back, BidirectionalCirculator front) : _front(front), _back(back), _direction(COUNTERCLOCKWISE) {} Circ_pair(BidirectionalCirculator back, BidirectionalCirculator front, Orientation dir) : _front(front), _back(back), _direction(dir) {} Circ_pair(BidirectionalCirculator front_and_back, Orientation dir) : _front(front_and_back), _back(front_and_back), _direction(dir) {} void initialize(BidirectionalCirculator new_back_and_front) { _back = _front = new_back_and_front; } void push_back(BidirectionalCirculator new_back) { _back = new_back; } void pop_back() { _back = before_back(); } void push_front(BidirectionalCirculator new_front) { _front = new_front; } void pop_front() { _front = before_front(); } BidirectionalCirculator front() const { return _front; } BidirectionalCirculator back() const { return _back; } Orientation direction() const { return _direction; } void set_direction(Orientation direction) { _direction = direction; } void change_dir() { if (_direction == CLOCKWISE) _direction = COUNTERCLOCKWISE; else _direction = CLOCKWISE; } BidirectionalCirculator before_back() { BidirectionalCirculator temp = _back; if (_direction == COUNTERCLOCKWISE) return ++temp; else return --temp; } BidirectionalCirculator after_back() { BidirectionalCirculator temp = _back; if (_direction == COUNTERCLOCKWISE) return --temp; else return ++temp; } BidirectionalCirculator before_front() { BidirectionalCirculator temp = _front; if (_direction == COUNTERCLOCKWISE) return --temp; else return ++temp; } BidirectionalCirculator after_front() { BidirectionalCirculator temp = _front; if (_direction == COUNTERCLOCKWISE) return ++temp; else return --temp; } private: BidirectionalCirculator _front, _back; Orientation _direction; }; } #endif // CGAL_CIRC_PAIR_H