// @(#)root/hist:$Id$
// Author: Olivier Couet 13/07/09

 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *

#ifndef ROOT_TGraphEdge
#define ROOT_TGraphEdge

#ifndef ROOT_TObject
#include "TObject.h"

#ifndef ROOT_TAttLine
#include "TAttLine.h"

struct GVizAgraph_t;
struct GVizAgedge_t;

class  TGraphNode;

//                                                                      //
// TGraphEdge                                                           //
//                                                                      //
// Interface to the graphviz package.                                   //
//                                                                      //

class TGraphEdge: public TObject, public TAttLine {


   TGraphNode *fNode1;     // First node
   TGraphNode *fNode2;     // Second node
   GVizAgedge_t  *fGVEdge; // Graphviz edge
   Double_t   *fX;         // X edge points (GV)
   Double_t   *fY;         // X edge points (GV)
   Int_t      *fN;         // number of edge points (GV)
                           // fN[0] = number of splines
                           // fN[1...n] = number of points in each spline
   Double_t    fArrX;      // Arrow X position
   Double_t    fArrY;      // Arrow Y position

   TGraphEdge(TGraphNode *n1, TGraphNode *n2);
   virtual ~TGraphEdge();

   void           CreateGVEdge(GVizAgraph_t *gv);
   virtual Int_t  DistancetoPrimitive(Int_t px, Int_t py);
   virtual void   ExecuteEvent(Int_t event, Int_t px, Int_t py);
   void           SetGVEdge(GVizAgedge_t *gve) {fGVEdge = gve;}
   GVizAgedge_t  *GetGVEdge() {return fGVEdge;}
   TGraphNode    *GetNode1() {return fNode1;}
   TGraphNode    *GetNode2() {return fNode2;}
   void           Layout();
   virtual void   Paint(Option_t *option="");
   virtual void   SavePrimitive(std::ostream &, Option_t *);
   void           SaveAttributes(std::ostream &, const char*);

   ClassDef(TGraphEdge,2)  //Graph edge class