src/lemon/graph_to_eps.h
author alpar
Tue, 11 Jan 2005 09:15:25 +0000
changeset 1073 bedab8bd915f
child 1085 5b7ca75297b5
permissions -rw-r--r--
graph_to_eps mission accomplished.
- lemon/graph_to_eps.h header created
- lemon/bezier.h: Tools to compute with bezier curves (unclean and undocumented
interface, used internally by graph_to_eps.h)
- demo/graph_to_eps_demo.cc: a simple demo for lemon/graph_to_eps.h
     1 /* -*- C++ -*-
     2  * src/lemon/graph_to_eps.h - Part of LEMON, a generic C++ optimization library
     3  *
     4  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     5  * (Egervary Combinatorial Optimization Research Group, EGRES).
     6  *
     7  * Permission to use, modify and distribute this software is granted
     8  * provided that this copyright notice appears in all copies. For
     9  * precise terms see the accompanying LICENSE file.
    10  *
    11  * This software is provided "AS IS" with no warranty of any kind,
    12  * express or implied, and with no claim as to its suitability for any
    13  * purpose.
    14  *
    15  */
    16 
    17 #ifndef LEMON_GRAPH_TO_EPS_H
    18 #define LEMON_GRAPH_TO_EPS_H
    19 
    20 #include<iostream>
    21 #include<fstream>
    22 #include<sstream>
    23 #include<algorithm>
    24 #include<vector>
    25 
    26 #include<lemon/xy.h>
    27 #include<lemon/maps.h>
    28 #include<lemon/bezier.h>
    29 
    30 ///\ingroup misc
    31 ///\file
    32 ///\brief Simple graph drawer
    33 ///
    34 ///\author Alpar Juttner
    35 
    36 namespace lemon {
    37 
    38 ///Data structure representing RGB colors.
    39 
    40 ///Data structure representing RGB colors.
    41 ///\ingroup misc
    42 class Color
    43 {
    44   double _r,_g,_b;
    45 public:
    46   ///Default constructor
    47   Color() {}
    48   ///Constructor
    49   Color(double r,double g,double b) :_r(r),_g(g),_b(b) {};
    50   ///Returns the red component
    51   double getR() {return _r;}
    52   ///Returns the green component
    53   double getG() {return _g;}
    54   ///Returns the blue component
    55   double getB() {return _b;}
    56   ///Set the color components
    57   void set(double r,double g,double b) { _r=r;_g=g;_b=b; };
    58 };
    59   
    60 ///Default traits class of \ref GraphToEps
    61 
    62 ///Default traits class of \ref GraphToEps
    63 ///
    64 ///\c G is the type of the underlying graph.
    65 template<class G>
    66 struct DefaultGraphToEpsTraits
    67 {
    68   typedef G Graph;
    69   typedef typename Graph::Node Node;
    70   typedef typename Graph::NodeIt NodeIt;
    71   typedef typename Graph::Edge Edge;
    72   typedef typename Graph::EdgeIt EdgeIt;
    73   typedef typename Graph::InEdgeIt InEdgeIt;
    74   typedef typename Graph::OutEdgeIt OutEdgeIt;
    75   
    76 
    77   const Graph &g;
    78 
    79   std::ostream& os;
    80   
    81   ConstMap<typename Graph::Node,xy<double> > _coords;
    82   ConstMap<typename Graph::Node,double > _nodeSizes;
    83 
    84   ConstMap<typename Graph::Node,Color > _nodeColors;
    85   ConstMap<typename Graph::Edge,Color > _edgeColors;
    86 
    87   ConstMap<typename Graph::Edge,double > _edgeWidths;
    88   
    89   double _edgeWidthScale;
    90   
    91   double _nodeScale;
    92   double _xBorder, _yBorder;
    93   double _scale;
    94   double _nodeBorderQuotient;
    95   
    96   bool _drawArrows;
    97   double _arrowLength, _arrowWidth;
    98   
    99   bool _showNodes, _showEdges;
   100 
   101   bool _enableParallel;
   102   double _parEdgeDist;
   103 
   104   bool _showNodeText;
   105   ConstMap<typename Graph::Node,bool > _nodeTexts;  
   106   double _nodeTextSize;
   107 
   108   bool _undir;
   109   bool _pleaseRemoveOsStream;
   110   ///Constructor
   111 
   112   ///Constructor
   113   ///\param _g is a reference to the graph to be printed
   114   ///\param _os is a reference to the output stream.
   115   ///\param _os is a reference to the output stream.
   116   ///\param _pros If it is \c true, then the \c ostream referenced by \c _os
   117   ///will be explicitly deallocated by the destructor.
   118   ///By default it is <tt>std::cout</tt>
   119   DefaultGraphToEpsTraits(const G &_g,std::ostream& _os=std::cout,
   120 			  bool _pros=false) :
   121     g(_g), os(_os),
   122     _coords(xy<double>(1,1)), _nodeSizes(1.0),
   123     _nodeColors(Color(1,1,1)), _edgeColors(Color(0,0,0)),
   124     _edgeWidths(1), _edgeWidthScale(0.3),
   125     _nodeScale(1.0), _xBorder(10), _yBorder(10), _scale(1.0),
   126     _nodeBorderQuotient(.1),
   127     _drawArrows(false), _arrowLength(1), _arrowWidth(0.3),
   128     _showNodes(true), _showEdges(true),
   129     _enableParallel(false), _parEdgeDist(1),
   130     _showNodeText(false), _nodeTexts(false), _nodeTextSize(1),
   131     _undir(false),
   132     _pleaseRemoveOsStream(_pros) {}
   133 };
   134 
   135 ///Helper class to implement the named parameters of \ref graphToEps()
   136 
   137 ///Helper class to implement the named parameters of \ref graphToEps()
   138 ///\todo Is 'helper class' a good name for this?
   139 ///
   140 template<class T> class GraphToEps : public T 
   141 {
   142   typedef typename T::Graph Graph;
   143   typedef typename Graph::Node Node;
   144   typedef typename Graph::NodeIt NodeIt;
   145   typedef typename Graph::Edge Edge;
   146   typedef typename Graph::EdgeIt EdgeIt;
   147   typedef typename Graph::InEdgeIt InEdgeIt;
   148   typedef typename Graph::OutEdgeIt OutEdgeIt;
   149 
   150   bool dontPrint;
   151 
   152   class edgeLess {
   153     const Graph &g;
   154   public:
   155     edgeLess(const Graph &_g) : g(_g) {}
   156     bool operator()(Edge a,Edge b) const 
   157     {
   158       Node ai=min(g.source(a),g.target(a));
   159       Node aa=max(g.source(a),g.target(a));
   160       Node bi=min(g.source(b),g.target(b));
   161       Node ba=max(g.source(b),g.target(b));
   162       return ai<bi ||
   163 	(ai==bi && (aa < ba || 
   164 		    (aa==ba && ai==g.source(a) && bi==g.target(b))));
   165     }
   166   };
   167   bool isParallel(Edge e,Edge f) const
   168   {
   169     return (g.source(e)==g.source(f)&&g.target(e)==g.target(f))||
   170       (g.source(e)==g.target(f)&&g.target(e)==g.source(f));
   171   }
   172   static xy<double> rot(xy<double> v) 
   173   {
   174     return xy<double>(v.y,-v.x);
   175   }
   176   template<class xy>
   177   static std::string psOut(const xy &p) 
   178     {
   179       std::ostringstream os;	
   180       os << p.x << ' ' << p.y;
   181       return os.str();
   182     }
   183   
   184 public:
   185   GraphToEps(const T &t) : T(t), dontPrint(false) {};
   186   
   187   template<class X> struct CoordsTraits : public T {
   188     const X &_coords;
   189     CoordsTraits(const T &t,const X &x) : T(t), _coords(x) {}
   190   };
   191   ///Sets the map of the node coordinates
   192 
   193   ///Sets the map of the node coordinates.
   194   ///\param x must be a node map with xy<double> or xy<int> values. 
   195   template<class X> GraphToEps<CoordsTraits<X> > coords(const X &x) {
   196     dontPrint=true;
   197     return GraphToEps<CoordsTraits<X> >(CoordsTraits<X>(*this,x));
   198   }
   199   template<class X> struct NodeSizesTraits : public T {
   200     const X &_nodeSizes;
   201     NodeSizesTraits(const T &t,const X &x) : T(t), _nodeSizes(x) {}
   202   };
   203   ///Sets the map of the node sizes
   204 
   205   ///Sets the map of the node sizes
   206   ///\param x must be a node map with \c double (or convertible) values. 
   207   template<class X> GraphToEps<NodeSizesTraits<X> > nodeSizes(const X &x)
   208   {
   209     dontPrint=true;
   210     return GraphToEps<NodeSizesTraits<X> >(NodeSizesTraits<X>(*this,x));
   211   }
   212   template<class X> struct NodeTextsTraits : public T {
   213     const X &_nodeTexts;
   214     NodeTextsTraits(const T &t,const X &x) : T(t), _nodeTexts(x) {}
   215   };
   216   ///Sets the text printed on the nodes
   217 
   218   ///Sets the text printed on the nodes
   219   ///\param x must be a node map with type that can be pushed to a standard
   220   ///ostream. 
   221   template<class X> GraphToEps<NodeTextsTraits<X> > nodeTexts(const X &x)
   222   {
   223     dontPrint=true;
   224     _showNodeText=true;
   225     return GraphToEps<NodeTextsTraits<X> >(NodeTextsTraits<X>(*this,x));
   226   }
   227    template<class X> struct EdgeWidthsTraits : public T {
   228     const X &_edgeWidths;
   229     EdgeWidthsTraits(const T &t,const X &x) : T(t), _edgeWidths(x) {}
   230   };
   231   ///Sets the map of the edge widths
   232 
   233   ///Sets the map of the edge widths
   234   ///\param x must be a edge map with \c double (or convertible) values. 
   235   template<class X> GraphToEps<EdgeWidthsTraits<X> > edgeWidths(const X &x)
   236   {
   237     dontPrint=true;
   238     return GraphToEps<EdgeWidthsTraits<X> >(EdgeWidthsTraits<X>(*this,x));
   239   }
   240 
   241   template<class X> struct NodeColorsTraits : public T {
   242     const X &_nodeColors;
   243     NodeColorsTraits(const T &t,const X &x) : T(t), _nodeColors(x) {}
   244   };
   245   ///Sets the map of the node colors
   246 
   247   ///Sets the map of the node colors
   248   ///\param x must be a node map with \ref Color values. 
   249   template<class X> GraphToEps<NodeColorsTraits<X> >
   250   nodeColors(const X &x)
   251   {
   252     dontPrint=true;
   253     return GraphToEps<NodeColorsTraits<X> >(NodeColorsTraits<X>(*this,x));
   254   }
   255   template<class X> struct EdgeColorsTraits : public T {
   256     const X &_edgeColors;
   257     EdgeColorsTraits(const T &t,const X &x) : T(t), _edgeColors(x) {}
   258   };
   259   ///Sets the map of the edge colors
   260 
   261   ///Sets the map of the edge colors
   262   ///\param x must be a edge map with \ref Color values. 
   263   template<class X> GraphToEps<EdgeColorsTraits<X> >
   264   edgeColors(const X &x)
   265   {
   266     dontPrint=true;
   267     return GraphToEps<EdgeColorsTraits<X> >(EdgeColorsTraits<X>(*this,x));
   268   }
   269   ///Sets a global scale factor for node sizes
   270 
   271   ///Sets a global scale factor for node sizes
   272   ///
   273   GraphToEps<T> &nodeScale(double d) {_nodeScale=d;return *this;}
   274   ///Sets a global scale factor for edge widths
   275 
   276   ///Sets a global scale factor for edge widths
   277   ///
   278   GraphToEps<T> &edgeWidthScale(double d) {_edgeWidthScale=d;return *this;}
   279   ///Sets a global scale factor for the whole picture
   280 
   281   ///Sets a global scale factor for the whole picture
   282   ///
   283   GraphToEps<T> &scale(double d) {_scale=d;return *this;}
   284   ///Sets the width of the border around the picture
   285 
   286   ///Sets the width of the border around the picture
   287   ///
   288   GraphToEps<T> &border(double b) {_xBorder=_yBorder=b;return *this;}
   289   ///Sets the width of the border around the picture
   290 
   291   ///Sets the width of the border around the picture
   292   ///
   293   GraphToEps<T> &border(double x, double y) {
   294     _xBorder=x;_yBorder=y;return *this;
   295   }
   296   ///Sets whether to draw arrows
   297 
   298   ///Sets whether to draw arrows
   299   ///
   300   GraphToEps<T> &drawArrows(bool b=true) {_drawArrows=b;return *this;}
   301   ///Sets the length of the arrowheads
   302 
   303   ///Sets the length of the arrowheads
   304   ///
   305   GraphToEps<T> &arrowLength(double d) {_arrowLength*=d;return *this;}
   306   ///Sets the width of the arrowheads
   307 
   308   ///Sets the width of the arrowheads
   309   ///
   310   GraphToEps<T> &arrowWidth(double d) {_arrowWidth*=d;return *this;}
   311   
   312   ///Enables parallel edges
   313 
   314   ///Enables parallel edges
   315   ///\todo Partially implemented
   316   GraphToEps<T> &enableParallel(bool b=true) {_enableParallel=b;return *this;}
   317   
   318   ///Sets the distance 
   319   
   320   ///Sets the distance 
   321   ///
   322   GraphToEps<T> &parEdgeDist(double d) {_parEdgeDist*=d;return *this;}
   323   
   324   ///Hides the edges
   325   
   326   ///Hides the edges
   327   ///
   328   GraphToEps<T> &hideEdges(bool b=true) {_showEdges=!b;return *this;}
   329   ///Hides the nodes
   330   
   331   ///Hides the nodes
   332   ///
   333   GraphToEps<T> &hideNodes(bool b=true) {_showNodes=!b;return *this;}
   334   
   335   ///Sets the size of the node texts
   336   
   337   ///Sets the size of the node texts
   338   ///
   339   GraphToEps<T> &nodeTextSize(double d) {_nodeTextSize=d;return *this;}
   340   ///Sets whether the the graph is undirected
   341 
   342   ///Sets whether the the graph is undirected
   343   ///
   344   GraphToEps<T> &undir(bool b=true) {_undir=b;return *this;}
   345   ///Sets whether the the graph is directed
   346 
   347   ///Sets whether the the graph is directed.
   348   ///Use it to show the undirected edges as a pair of directed ones.
   349   GraphToEps<T> &bidir(bool b=true) {_undir=!b;return *this;}
   350   
   351   ~GraphToEps() 
   352   {
   353     if(dontPrint) return;
   354     
   355     os << "%!PS-Adobe-2.0 EPSF-2.0\n";
   356     //\todo: Chech whether the graph is empty.
   357     BoundingBox<double> bb;
   358     for(NodeIt n(g);n!=INVALID;++n) {
   359       double ns=_nodeSizes[n]*_nodeScale;
   360       xy<double> p(ns,ns);
   361       bb+=p+_coords[n];
   362       bb+=-p+_coords[n];
   363       }
   364     os << "%%BoundingBox: "
   365 	 << bb.left()*  _scale-_xBorder << ' '
   366 	 << bb.bottom()*_scale-_yBorder << ' '
   367 	 << bb.right()* _scale+_xBorder << ' '
   368 	 << bb.top()*   _scale+_yBorder << '\n';
   369     //x1 y1 x2 y2 x3 y3 cr cg cb w
   370     os << "/lb { setlinewidth setrgbcolor newpath moveto\n"
   371        << "      4 2 roll 1 index 1 index curveto stroke } bind def\n";
   372     os << "/l { setlinewidth setrgbcolor newpath moveto lineto stroke } bind def\n";
   373     os << "/c { newpath dup 3 index add 2 index moveto 0 360 arc closepath } bind def\n";
   374     // x y r cr cg cb
   375     os << "/n { setrgbcolor 2 index 2 index 2 index c fill\n"
   376        << "     0 0 0 setrgbcolor dup "
   377        << _nodeBorderQuotient << " mul setlinewidth "
   378        << 1+_nodeBorderQuotient/2 << " div c stroke\n"
   379        << "   } bind def\n";
   380     os << "/arrl " << _arrowLength << " def\n";
   381     os << "/arrw " << _arrowWidth << " def\n";
   382     // l dx_norm dy_norm
   383     os << "/lrl { 2 index mul exch 2 index mul exch rlineto pop} bind def\n";
   384     //len w dx_norm dy_norm x1 y1 cr cg cb
   385     os << "/arr { setrgbcolor /y1 exch def /x1 exch def /dy exch def /dx exch def\n"
   386        << "       /w exch def /len exch def\n"
   387       //	 << "       0.1 setlinewidth x1 y1 moveto dx len mul dy len mul rlineto stroke"
   388        << "       newpath x1 dy w 2 div mul add y1 dx w 2 div mul sub moveto\n"
   389        << "       len w sub arrl sub dx dy lrl\n"
   390        << "       arrw dy dx neg lrl\n"
   391        << "       dx arrl w add mul dy w 2 div arrw add mul sub\n"
   392        << "       dy arrl w add mul dx w 2 div arrw add mul add rlineto\n"
   393        << "       dx arrl w add mul neg dy w 2 div arrw add mul sub\n"
   394        << "       dy arrl w add mul neg dx w 2 div arrw add mul add rlineto\n"
   395        << "       arrw dy dx neg lrl\n"
   396        << "       len w sub arrl sub neg dx dy lrl\n"
   397        << "       closepath fill } bind def\n";
   398     os << "/cshow { 2 index 2 index moveto dup stringwidth pop\n"
   399        << "         neg 2 div fosi .35 mul neg rmoveto show pop pop} def\n";
   400 
   401     os << "\ngsave\n";
   402     if(_scale!=1.0) os << _scale << " dup scale\n";
   403     
   404     os << "%Edges:\ngsave\n";
   405     
   406     if(_showEdges)
   407       if(_enableParallel) {
   408 	std::vector<Edge> el;
   409 	for(EdgeIt e(g);e!=INVALID;++e)
   410 	  if(!_undir||g.source(e)<g.target(e)) el.push_back(e);
   411 	sort(el.begin(),el.end(),edgeLess(g));
   412 	
   413 	typename std::vector<Edge>::iterator j;
   414 	for(typename std::vector<Edge>::iterator i=el.begin();i!=el.end();i=j) {
   415 	  for(j=i+1;j!=el.end()&&isParallel(*i,*j);++j) ;
   416 
   417 	  double sw=0;
   418 	  for(typename std::vector<Edge>::iterator e=i;e!=j;++e)
   419 	    sw+=_edgeWidths[*e]*_edgeWidthScale+_parEdgeDist;
   420 	  sw-=_parEdgeDist;
   421 	  sw/=-2.0;
   422 	  xy<double> d(_coords[g.target(*i)]-_coords[g.source(*i)]);
   423 	  double l=sqrt(d.normSquare());
   424 	  d/=l;
   425 	  
   426 	  for(typename std::vector<Edge>::iterator e=i;e!=j;++e) {
   427 	    sw+=_edgeWidths[*e]*_edgeWidthScale/2.0;
   428 	    xy<double> m(_coords[g.target(*e)]+_coords[g.source(*e)]);
   429 	    m=m/2.0+rot(d)*sw/.75;
   430 	    if(_drawArrows) {
   431 	      const int INERPOL_PREC=20;
   432 	      xy<double> s=_coords[g.source(*e)];
   433 	      xy<double> t=_coords[g.target(*e)];
   434 	      double rn=_nodeSizes[g.target(*e)]*_nodeScale;
   435 	      rn*=rn;
   436 	      Bezier3 bez(s,m,m,t);
   437 	      double t1=0,t2=1;
   438 	      for(int i=0;i<INERPOL_PREC;++i)
   439 		if((bez((t1+t2)/2)-t).normSquare()>rn) t1=(t1+t2)/2;
   440 		else t2=(t1+t2)/2;
   441 	      xy<double> apoint=bez((t1+t2)/2);
   442 	      rn = _nodeSizes[g.target(*e)]*_nodeScale+_arrowLength+
   443 		_edgeWidths[*e]*_edgeWidthScale;
   444 	      rn*=rn;
   445 	      t1=0;t2=1;
   446 	      for(int i=0;i<INERPOL_PREC;++i)
   447 		if((bez((t1+t2)/2)-t).normSquare()>rn) t1=(t1+t2)/2;
   448 		else t2=(t1+t2)/2;
   449 	      xy<double> linend=bez((t1+t2)/2);	      
   450 	      bez=bez.before((t1+t2)/2);
   451 	      rn=_nodeSizes[g.source(*e)]*_nodeScale; rn*=rn;
   452 	      t1=0;t2=1;
   453 	      for(int i=0;i<INERPOL_PREC;++i)
   454 		if((bez((t1+t2)/2)-s).normSquare()>rn) t2=(t1+t2)/2;
   455 		else t1=(t1+t2)/2;
   456 	      bez=bez.after((t1+t2)/2);
   457 	      os << _edgeWidths[*e]*_edgeWidthScale << " setlinewidth "
   458 		 << _edgeColors[*e].getR() << ' '
   459 		 << _edgeColors[*e].getG() << ' '
   460 		 << _edgeColors[*e].getB() << " setrgbcolor newpath\n"
   461 		 << bez.p1.x << ' ' <<  bez.p1.y << " moveto\n"
   462 		 << bez.p2.x << ' ' << bez.p2.y << ' '
   463 		 << bez.p3.x << ' ' << bez.p3.y << ' '
   464 		 << bez.p4.x << ' ' << bez.p4.y << " curveto stroke\n";
   465 	      xy<double> dd(rot(linend-apoint));
   466 	      dd*=(_edgeWidths[*e]*_edgeWidthScale+_arrowWidth)/
   467 		sqrt(dd.normSquare());
   468 	      os << "newpath " << psOut(apoint) << " moveto "
   469 		 << psOut(linend+dd) << " lineto "
   470 		 << psOut(linend-dd) << " lineto closepath fill\n";
   471 	    }
   472 	    else {
   473 	      os << _coords[g.source(*e)].x << ' '
   474 		 << _coords[g.source(*e)].y << ' '
   475 		 << m.x << ' ' << m.y << ' '
   476 		 << _coords[g.target(*e)].x << ' '
   477 		 << _coords[g.target(*e)].y << ' '
   478 		 << _edgeColors[*e].getR() << ' '
   479 		 << _edgeColors[*e].getG() << ' '
   480 		 << _edgeColors[*e].getB() << ' '
   481 		 << _edgeWidths[*e]*_edgeWidthScale << " lb\n";
   482 	    }
   483 	    sw+=_edgeWidths[*e]*_edgeWidthScale/2.0+_parEdgeDist;
   484 	  }
   485 	}
   486       }
   487       else for(EdgeIt e(g);e!=INVALID;++e)
   488 	if(!_undir||g.source(e)<g.target(e))
   489 	  if(_drawArrows) {
   490 	    xy<double> d(_coords[g.target(e)]-_coords[g.source(e)]);
   491 	    double l=sqrt(d.normSquare());
   492 	    d/=l;
   493 	    xy<double> x1(d*_nodeScale*_nodeSizes[g.source(e)]+
   494 			  _coords[g.source(e)]);
   495 	    os << l-(_nodeSizes[g.source(e)]+
   496 		     _nodeSizes[g.target(e)])*_nodeScale << ' '
   497 	       << _edgeWidths[e]*_edgeWidthScale << ' '
   498 	       << d.x << ' ' << d.y << ' '
   499 	       << x1.x << ' ' << x1.y << ' '
   500 	       << _edgeColors[e].getR() << ' '
   501 	       << _edgeColors[e].getG() << ' '
   502 	       << _edgeColors[e].getB() << " arr\n";
   503 	  }
   504 	  else os << _coords[g.source(e)].x << ' '
   505 		  << _coords[g.source(e)].y << ' '
   506 		  << _coords[g.target(e)].x << ' '
   507 		  << _coords[g.target(e)].y << ' '
   508 		  << _edgeColors[e].getR() << ' '
   509 		  << _edgeColors[e].getG() << ' '
   510 		  << _edgeColors[e].getB() << ' '
   511 		  << _edgeWidths[e]*_edgeWidthScale << " l\n";
   512     os << "grestore\n%Nodes:\ngsave\n";
   513     if(_showNodes)
   514       for(NodeIt n(g);n!=INVALID;++n)
   515 	os << _coords[n].x << ' ' << _coords[n].y << ' '
   516 	   << _nodeSizes[n]*_nodeScale << ' '
   517 	   << _nodeColors[n].getR() << ' '
   518 	   << _nodeColors[n].getG() << ' '
   519 	   << _nodeColors[n].getB() << " n\n"; 
   520     if(_showNodeText) {
   521       os << "grestore\n%Node texts:\ngsave\n";
   522       os << "/fosi " << _nodeTextSize << " def\n";
   523       os << "(Helvetica) findfont fosi scalefont setfont\n";
   524       os << "0 0 0 setrgbcolor\n";
   525       for(NodeIt n(g);n!=INVALID;++n)
   526 	os << _coords[n].x << ' ' << _coords[n].y
   527 	   << " (" << _nodeTexts[n] << ") cshow\n";
   528     }
   529     os << "grestore\ngrestore\n";
   530 
   531     //CleanUp:
   532     if(_pleaseRemoveOsStream) {delete &os;}
   533   } 
   534 };
   535 
   536 
   537 ///Generates an EPS file from a graph
   538 
   539 ///\ingroup misc
   540 ///Generates an EPS file from a graph.
   541 ///\param g is a reference to the graph to be printed
   542 ///\param os is a reference to the output stream.
   543 ///By default it is <tt>std::cout</tt>
   544 ///
   545 ///This function also has a lot of \ref named-templ-param "named parameters",
   546 ///they are declared as the members of class \ref GraphToEps. The following
   547 ///example shows how to use these parameters.
   548 ///\code
   549 /// graphToEps(g).scale(10).coords(coords)
   550 ///              .nodeScale(2).nodeSizes(sizes)
   551 ///              .edgeWidthScale(.4);
   552 ///\endcode
   553 ///\sa GraphToEps
   554 ///\sa graphToEps(G &g, char *file_name)
   555 template<class G>
   556 GraphToEps<DefaultGraphToEpsTraits<G> > 
   557 graphToEps(G &g, std::ostream& os=std::cout)
   558 {
   559   return 
   560     GraphToEps<DefaultGraphToEpsTraits<G> >(DefaultGraphToEpsTraits<G>(g,os));
   561 }
   562  
   563 ///Generates an EPS file from a graph
   564 
   565 //\ingroup misc
   566 ///This function does the same as
   567 ///\ref graphToEps(G &g,std::ostream& os)
   568 ///but it writes its output into the file \c file_name
   569 ///instead of a stream.
   570 ///\sa graphToEps(G &g, std::ostream& os)
   571 template<class G>
   572 GraphToEps<DefaultGraphToEpsTraits<G> > 
   573 graphToEps(G &g,char *file_name)
   574 {
   575   return GraphToEps<DefaultGraphToEpsTraits<G> >
   576     (DefaultGraphToEpsTraits<G>(g,*new std::ofstream(file_name),true));
   577 }
   578 
   579 //Generates an EPS file from a graph.
   580 //\param g is a reference to the graph to be printed
   581 //\param file_name is the output file_name.
   582 //
   583 //This function also has a lot of \ref named-templ-param "named parameters",
   584 //they are declared as the members of class \ref GraphToEps. The following
   585 //example shows how to use these parameters.
   586 //\code
   587 // graphToEps(g).scale(10).coords(coords)
   588 //              .nodeScale(2).nodeSizes(sizes)
   589 //              .edgeWidthScale(.4);
   590 //\endcode
   591 //\sa GraphToEps
   592 //\todo Avoid duplicated documentation
   593 //\bug Exception handling is missing? (Or we can just ignore it?)
   594 
   595 } //END OF NAMESPACE LEMON
   596 
   597 #endif // LEMON_GRAPH_TO_EPS_H