1 /* -*- mode: C++; indent-tabs-mode: nil; -*-
 
     3  * This file is a part of LEMON, a generic C++ optimization library.
 
     5  * Copyright (C) 2003-2008
 
     6  * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
 
     7  * (Egervary Research Group on Combinatorial Optimization, EGRES).
 
     9  * Permission to use, modify and distribute this software is granted
 
    10  * provided that this copyright notice appears in all copies. For
 
    11  * precise terms see the accompanying LICENSE file.
 
    13  * This software is provided "AS IS" with no warranty of any kind,
 
    14  * express or implied, and with no claim as to its suitability for any
 
    26 ///\brief A simple two dimensional vector and a bounding box implementation
 
    28 /// The class \ref lemon::dim2::Point "dim2::Point" implements
 
    29 /// a two dimensional vector with the usual operations.
 
    31 /// The class \ref lemon::dim2::Box "dim2::Box" can be used to determine
 
    32 /// the rectangular bounding box of a set of
 
    33 /// \ref lemon::dim2::Point "dim2::Point"'s.
 
    37   ///Tools for handling two dimensional coordinates
 
    39   ///This namespace is a storage of several
 
    40   ///tools for handling two dimensional coordinates
 
    46   /// Two dimensional vector (plain vector)
 
    48   /// A simple two dimensional vector (plain vector) implementation
 
    49   /// with the usual vector operations.
 
    62       ///Default constructor
 
    65       ///Construct an instance from coordinates
 
    66       Point(T a, T b) : x(a), y(b) { }
 
    68       ///Returns the dimension of the vector (i.e. returns 2).
 
    70       ///The dimension of the vector.
 
    71       ///This function always returns 2.
 
    72       int size() const { return 2; }
 
    74       ///Subscripting operator
 
    76       ///\c p[0] is \c p.x and \c p[1] is \c p.y
 
    78       T& operator[](int idx) { return idx == 0 ? x : y; }
 
    80       ///Const subscripting operator
 
    82       ///\c p[0] is \c p.x and \c p[1] is \c p.y
 
    84       const T& operator[](int idx) const { return idx == 0 ? x : y; }
 
    86       ///Conversion constructor
 
    87       template<class TT> Point(const Point<TT> &p) : x(p.x), y(p.y) {}
 
    89       ///Give back the square of the norm of the vector
 
    90       T normSquare() const {
 
    94       ///Increment the left hand side by \c u
 
    95       Point<T>& operator +=(const Point<T>& u) {
 
   101       ///Decrement the left hand side by \c u
 
   102       Point<T>& operator -=(const Point<T>& u) {
 
   108       ///Multiply the left hand side with a scalar
 
   109       Point<T>& operator *=(const T &u) {
 
   115       ///Divide the left hand side by a scalar
 
   116       Point<T>& operator /=(const T &u) {
 
   122       ///Return the scalar product of two vectors
 
   123       T operator *(const Point<T>& u) const {
 
   127       ///Return the sum of two vectors
 
   128       Point<T> operator+(const Point<T> &u) const {
 
   133       ///Return the negative of the vector
 
   134       Point<T> operator-() const {
 
   140       ///Return the difference of two vectors
 
   141       Point<T> operator-(const Point<T> &u) const {
 
   146       ///Return a vector multiplied by a scalar
 
   147       Point<T> operator*(const T &u) const {
 
   152       ///Return a vector divided by a scalar
 
   153       Point<T> operator/(const T &u) const {
 
   159       bool operator==(const Point<T> &u) const {
 
   160         return (x==u.x) && (y==u.y);
 
   164       bool operator!=(Point u) const {
 
   165         return  (x!=u.x) || (y!=u.y);
 
   174   template <typename T>
 
   175   inline Point<T> makePoint(const T& x, const T& y) {
 
   176     return Point<T>(x, y);
 
   179   ///Return a vector multiplied by a scalar
 
   181   ///Return a vector multiplied by a scalar.
 
   183   template<typename T> Point<T> operator*(const T &u,const Point<T> &x) {
 
   187   ///Read a plain vector from a stream
 
   189   ///Read a plain vector from a stream.
 
   193   inline std::istream& operator>>(std::istream &is, Point<T> &z) {
 
   196       if (c != '(') is.putback(c);
 
   200     if (!(is >> z.x)) return is;
 
   202       if (c != ',') is.putback(c);
 
   206     if (!(is >> z.y)) return is;
 
   208       if (c != ')') is.putback(c);
 
   215   ///Write a plain vector to a stream
 
   217   ///Write a plain vector to a stream.
 
   221   inline std::ostream& operator<<(std::ostream &os, const Point<T>& z)
 
   223     os << "(" << z.x << "," << z.y << ")";
 
   227   ///Rotate by 90 degrees
 
   229   ///Returns the parameter rotated by 90 degrees in positive direction.
 
   233   inline Point<T> rot90(const Point<T> &z)
 
   235     return Point<T>(-z.y,z.x);
 
   238   ///Rotate by 180 degrees
 
   240   ///Returns the parameter rotated by 180 degrees.
 
   244   inline Point<T> rot180(const Point<T> &z)
 
   246     return Point<T>(-z.x,-z.y);
 
   249   ///Rotate by 270 degrees
 
   251   ///Returns the parameter rotated by 90 degrees in negative direction.
 
   255   inline Point<T> rot270(const Point<T> &z)
 
   257     return Point<T>(z.y,-z.x);
 
   262   /// Bounding box of plain vectors (points).
 
   264   /// A class to calculate or store the bounding box of plain vectors
 
   265   /// (\ref Point "points").
 
   268       Point<T> _bottom_left, _top_right;
 
   272       ///Default constructor: creates an empty box
 
   273       Box() { _empty = true; }
 
   275       ///Construct a box from one point
 
   277         _bottom_left = _top_right = a;
 
   281       ///Construct a box from two points
 
   283       ///Construct a box from two points.
 
   284       ///\param a The bottom left corner.
 
   285       ///\param b The top right corner.
 
   286       ///\warning The coordinates of the bottom left corner must be no more
 
   287       ///than those of the top right one.
 
   288       Box(Point<T> a,Point<T> b)
 
   295       ///Construct a box from four numbers
 
   297       ///Construct a box from four numbers.
 
   298       ///\param l The left side of the box.
 
   299       ///\param b The bottom of the box.
 
   300       ///\param r The right side of the box.
 
   301       ///\param t The top of the box.
 
   302       ///\warning The left side must be no more than the right side and
 
   303       ///bottom must be no more than the top.
 
   306         _bottom_left=Point<T>(l,b);
 
   307         _top_right=Point<T>(r,t);
 
   311       ///Return \c true if the box is empty.
 
   313       ///Return \c true if the box is empty (i.e. return \c false
 
   314       ///if at least one point was added to the box or the coordinates of
 
   315       ///the box were set).
 
   317       ///The coordinates of an empty box are not defined.
 
   322       ///Make the box empty
 
   327       ///Give back the bottom left corner of the box
 
   329       ///Give back the bottom left corner of the box.
 
   330       ///If the box is empty, then the return value is not defined.
 
   331       Point<T> bottomLeft() const {
 
   335       ///Set the bottom left corner of the box
 
   337       ///Set the bottom left corner of the box.
 
   338       ///\pre The box must not be empty.
 
   339       void bottomLeft(Point<T> p) {
 
   343       ///Give back the top right corner of the box
 
   345       ///Give back the top right corner of the box.
 
   346       ///If the box is empty, then the return value is not defined.
 
   347       Point<T> topRight() const {
 
   351       ///Set the top right corner of the box
 
   353       ///Set the top right corner of the box.
 
   354       ///\pre The box must not be empty.
 
   355       void topRight(Point<T> p) {
 
   359       ///Give back the bottom right corner of the box
 
   361       ///Give back the bottom right corner of the box.
 
   362       ///If the box is empty, then the return value is not defined.
 
   363       Point<T> bottomRight() const {
 
   364         return Point<T>(_top_right.x,_bottom_left.y);
 
   367       ///Set the bottom right corner of the box
 
   369       ///Set the bottom right corner of the box.
 
   370       ///\pre The box must not be empty.
 
   371       void bottomRight(Point<T> p) {
 
   373         _bottom_left.y = p.y;
 
   376       ///Give back the top left corner of the box
 
   378       ///Give back the top left corner of the box.
 
   379       ///If the box is empty, then the return value is not defined.
 
   380       Point<T> topLeft() const {
 
   381         return Point<T>(_bottom_left.x,_top_right.y);
 
   384       ///Set the top left corner of the box
 
   386       ///Set the top left corner of the box.
 
   387       ///\pre The box must not be empty.
 
   388       void topLeft(Point<T> p) {
 
   390         _bottom_left.x = p.x;
 
   393       ///Give back the bottom of the box
 
   395       ///Give back the bottom of the box.
 
   396       ///If the box is empty, then the return value is not defined.
 
   398         return _bottom_left.y;
 
   401       ///Set the bottom of the box
 
   403       ///Set the bottom of the box.
 
   404       ///\pre The box must not be empty.
 
   409       ///Give back the top of the box
 
   411       ///Give back the top of the box.
 
   412       ///If the box is empty, then the return value is not defined.
 
   417       ///Set the top of the box
 
   419       ///Set the top of the box.
 
   420       ///\pre The box must not be empty.
 
   425       ///Give back the left side of the box
 
   427       ///Give back the left side of the box.
 
   428       ///If the box is empty, then the return value is not defined.
 
   430         return _bottom_left.x;
 
   433       ///Set the left side of the box
 
   435       ///Set the left side of the box.
 
   436       ///\pre The box must not be empty.
 
   441       /// Give back the right side of the box
 
   443       /// Give back the right side of the box.
 
   444       ///If the box is empty, then the return value is not defined.
 
   449       ///Set the right side of the box
 
   451       ///Set the right side of the box.
 
   452       ///\pre The box must not be empty.
 
   457       ///Give back the height of the box
 
   459       ///Give back the height of the box.
 
   460       ///If the box is empty, then the return value is not defined.
 
   462         return _top_right.y-_bottom_left.y;
 
   465       ///Give back the width of the box
 
   467       ///Give back the width of the box.
 
   468       ///If the box is empty, then the return value is not defined.
 
   470         return _top_right.x-_bottom_left.x;
 
   473       ///Checks whether a point is inside the box
 
   474       bool inside(const Point<T>& u) const {
 
   478           return ( (u.x-_bottom_left.x)*(_top_right.x-u.x) >= 0 &&
 
   479                    (u.y-_bottom_left.y)*(_top_right.y-u.y) >= 0 );
 
   483       ///Increments the box with a point
 
   485       ///Increments the box with a point.
 
   487       Box& add(const Point<T>& u){
 
   489           _bottom_left = _top_right = u;
 
   493           if (_bottom_left.x > u.x) _bottom_left.x = u.x;
 
   494           if (_bottom_left.y > u.y) _bottom_left.y = u.y;
 
   495           if (_top_right.x < u.x) _top_right.x = u.x;
 
   496           if (_top_right.y < u.y) _top_right.y = u.y;
 
   501       ///Increments the box to contain another box
 
   503       ///Increments the box to contain another box.
 
   505       Box& add(const Box &u){
 
   513       ///Intersection of two boxes
 
   515       ///Intersection of two boxes.
 
   517       Box operator&(const Box& u) const {
 
   519         if (_empty || u._empty) {
 
   522           b._bottom_left.x = std::max(_bottom_left.x, u._bottom_left.x);
 
   523           b._bottom_left.y = std::max(_bottom_left.y, u._bottom_left.y);
 
   524           b._top_right.x = std::min(_top_right.x, u._top_right.x);
 
   525           b._top_right.y = std::min(_top_right.y, u._top_right.y);
 
   526           b._empty = b._bottom_left.x > b._top_right.x ||
 
   527                      b._bottom_left.y > b._top_right.y;
 
   535   ///Read a box from a stream
 
   537   ///Read a box from a stream.
 
   540   inline std::istream& operator>>(std::istream &is, Box<T>& b) {
 
   544       if (c != '(') is.putback(c);
 
   548     if (!(is >> p)) return is;
 
   551       if (c != ',') is.putback(c);
 
   555     if (!(is >> p)) return is;
 
   558       if (c != ')') is.putback(c);
 
   565   ///Write a box to a stream
 
   567   ///Write a box to a stream.
 
   570   inline std::ostream& operator<<(std::ostream &os, const Box<T>& b)
 
   572     os << "(" << b.bottomLeft() << "," << b.topRight() << ")";
 
   576   ///Map of x-coordinates of a <tt>Point</tt>-map
 
   578   ///Map of x-coordinates of a \ref Point "Point"-map.
 
   586     typedef typename M::Value::Value Value;
 
   587     typedef typename M::Key Key;
 
   589     XMap(M& map) : _map(map) {}
 
   590     Value operator[](Key k) const {return _map[k].x;}
 
   591     void set(Key k,Value v) {_map.set(k,typename M::Value(v,_map[k].y));}
 
   594   ///Returns an XMap class
 
   596   ///This function just returns an XMap class.
 
   599   inline XMap<M> xMap(M &m)
 
   605   inline XMap<M> xMap(const M &m)
 
   610   ///Constant (read only) version of XMap
 
   612   ///Constant (read only) version of XMap.
 
   620     typedef typename M::Value::Value Value;
 
   621     typedef typename M::Key Key;
 
   623     ConstXMap(const M &map) : _map(map) {}
 
   624     Value operator[](Key k) const {return _map[k].x;}
 
   627   ///Returns a ConstXMap class
 
   629   ///This function just returns a ConstXMap class.
 
   630   ///\relates ConstXMap
 
   632   inline ConstXMap<M> xMap(const M &m)
 
   634     return ConstXMap<M>(m);
 
   637   ///Map of y-coordinates of a <tt>Point</tt>-map
 
   639   ///Map of y-coordinates of a \ref Point "Point"-map.
 
   647     typedef typename M::Value::Value Value;
 
   648     typedef typename M::Key Key;
 
   650     YMap(M& map) : _map(map) {}
 
   651     Value operator[](Key k) const {return _map[k].y;}
 
   652     void set(Key k,Value v) {_map.set(k,typename M::Value(_map[k].x,v));}
 
   655   ///Returns a YMap class
 
   657   ///This function just returns a YMap class.
 
   660   inline YMap<M> yMap(M &m)
 
   666   inline YMap<M> yMap(const M &m)
 
   671   ///Constant (read only) version of YMap
 
   673   ///Constant (read only) version of YMap.
 
   681     typedef typename M::Value::Value Value;
 
   682     typedef typename M::Key Key;
 
   684     ConstYMap(const M &map) : _map(map) {}
 
   685     Value operator[](Key k) const {return _map[k].y;}
 
   688   ///Returns a ConstYMap class
 
   690   ///This function just returns a ConstYMap class.
 
   691   ///\relates ConstYMap
 
   693   inline ConstYMap<M> yMap(const M &m)
 
   695     return ConstYMap<M>(m);
 
   699   ///\brief Map of the normSquare() of a <tt>Point</tt>-map
 
   701   ///Map of the \ref Point::normSquare() "normSquare()"
 
   702   ///of a \ref Point "Point"-map.
 
   709     typedef typename M::Value::Value Value;
 
   710     typedef typename M::Key Key;
 
   712     NormSquareMap(const M &map) : _map(map) {}
 
   713     Value operator[](Key k) const {return _map[k].normSquare();}
 
   716   ///Returns a NormSquareMap class
 
   718   ///This function just returns a NormSquareMap class.
 
   719   ///\relates NormSquareMap
 
   721   inline NormSquareMap<M> normSquareMap(const M &m)
 
   723     return NormSquareMap<M>(m);
 
   732 #endif //LEMON_DIM2_H