[u/mrichter/AliRoot.git] / MUON / AliMUONContourMaker.cxx

/**************************************************************************
* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
*                                                                        *
* Author: The ALICE Off-line Project.                                    *
* Contributors are mentioned in the code where appropriate.              *
*                                                                        *
* Permission to use, copy, modify and distribute this software and its   *
* documentation strictly for non-commercial purposes is hereby granted   *
* without fee, provided that the above copyright notice appears in all   *
* copies and that both the copyright notice and this permission notice   *
* appear in the supporting documentation. The authors make no claims     *
* about the suitability of this software for any purpose. It is          *
* provided "as is" without express or implied warranty.                  *
**************************************************************************/

// $Id$

///
/// Maker/merger of contours. Can create contour from a set polygons or
/// merger a set of contours into a single one.
/// 
/// This is based on (one of the) algorithm found in 
/// Diane L. Souvaine and Iliana Bjorling-Sachs,
/// Proceedings of the IEEE, Vol. 80, No. 9, September 1992, p. 1449
///
/// Note that besides the AliMUON prefix, nothing is really MUON specific
/// in this class...
///
/// \author Laurent Aphecetche, Subatech
///

#include "AliMUONContourMaker.h"

#include "AliCodeTimer.h"
#include "AliLog.h"
#include "AliMUONContour.h"
#include "AliMUONPointWithRef.h"
#include "AliMUONPolygon.h"
#include "AliMUONSegment.h"
#include "AliMUONSegmentTree.h"
#include "Riostream.h"
#include "TArrayD.h"
#include "TMath.h"
#include <cassert>
#include "TArrayI.h"

/// \cond CLASSIMP
ClassImp(AliMUONContourMaker)
/// \endcond

//_____________________________________________________________________________
AliMUONContourMaker::AliMUONContourMaker() 
{
/// Default constructor
}


//_____________________________________________________________________________
AliMUONContourMaker::~AliMUONContourMaker()
{
/// Destructor
}

//_____________________________________________________________________________
AliMUONContour* 
AliMUONContourMaker::CreateContour(const TObjArray& polygons, const char* name) const
{
  /// Create the contour of the polygon array
  /// and get back the intermediate verticals and horizontal segments
  /// both arrays are arrays of AliMUONSegment objects.
  
  AliCodeTimerAuto("",0);
  
  if ( polygons.IsEmpty() ) return 0x0; // protection against user error...
  
  // Sanity check : insure that all polygons are oriented counter-clockwise
  TIter next(&polygons);
  AliMUONPolygon* pol;
  while ( ( pol = static_cast<AliMUONPolygon*>(next()) ) )
  {
    if ( !pol->IsCounterClockwiseOriented() )
    {
      AliError(Form("Got a clockwise oriented polygon in CreateContour(%s). That's not OK !",name));
      StdoutToAliError(polygons.Print());
      return 0x0;
    }
  }
  
  AliMUONContour* contour(0x0);
  
  if ( polygons.GetLast() == 0 ) 
  {
    AliCodeTimerAuto("Trivial case",1);
    contour = new AliMUONContour(name);
    pol = static_cast<AliMUONPolygon*>(polygons.First());
    contour->Add(*pol);
    contour->AssertOrientation();
    return contour;
  }
  
  TObjArray polygonVerticalEdges; // arrray of AliMUONSegment objects  
  polygonVerticalEdges.SetOwner(kTRUE);
  // get vertical edges of input polygons
  GetVerticalEdges(polygons,polygonVerticalEdges);
  
  // sort them in ascending x order
  // if same x, insure that left edges are before right edges
  // within same x, order by increasing bottommost y (see AliMUONSegment::Compare method)
  polygonVerticalEdges.Sort();
  
  if ( polygonVerticalEdges.GetLast()+1 < 2 ) 
  {
    polygons.Print();
    AliFatal(Form("Got too few edges here for createContour %s",name));
  }
  
  // Find the vertical edges of the merged contour. This is the meat of the algorithm...
  TObjArray contourVerticalEdges;
  contourVerticalEdges.SetOwner(kTRUE);
  Sweep(polygonVerticalEdges,contourVerticalEdges);
  
  TObjArray horizontals;
  horizontals.SetOwner(kTRUE);
  VerticalToHorizontal(contourVerticalEdges,horizontals);
  
  contour = FinalizeContour(contourVerticalEdges,horizontals);
  
  if ( contour && name ) contour->SetName(name);
  
  return contour;
}

//_____________________________________________________________________________
AliMUONContour* 
AliMUONContourMaker::FinalizeContour(const TObjArray& verticals,
                                     const TObjArray& horizontals) const
{  
  /// For a list of vertical and horizontal edges, we build the final
  /// contour object.
  
  AliCodeTimerAuto("",0);
  
  TObjArray all; // array of AliMUONSegment
  TObjArray inorder; // array of AliMUONSegment

  all.SetOwner(kFALSE);
  inorder.SetOwner(kFALSE);
    
  for ( Int_t i = 0; i <= verticals.GetLast(); ++i ) 
  {
    all.Add(verticals.UncheckedAt(i));
    all.Add(horizontals.UncheckedAt(i));
  }

  TArrayI alreadyAdded(all.GetLast()+1);
  alreadyAdded.Reset();
  
  Int_t i(0);
  
  AliMUONContour* contour = new AliMUONContour;
  
  int total(0);
  
  while ( !all.IsEmpty() )
  {
    total++;
    
    if ( total > 1000 ) 
    {
      AliError("Total 1000 reached !!!!");
      return 0x0;
    }
    
    AliMUONSegment* si = static_cast<AliMUONSegment*>(all.UncheckedAt(i));
    inorder.Add(si);
    alreadyAdded[i] = 1;
    const AliMUONSegment* all0 = static_cast<const AliMUONSegment*>(all.First());
    if ( i != 0 && AliMUONSegment::AreEqual(si->EndX(),all0->StartX()) && AliMUONSegment::AreEqual(si->EndY(),all0->StartY()) )
    {
      Int_t n(-1);
      
      AliMUONPolygon polygon(inorder.GetLast()+2);

      // we got a cycle. Add it to the contour
      for ( Int_t j = 0; j <= inorder.GetLast(); ++j ) 
      {
        AliMUONSegment* s = static_cast<AliMUONSegment*>(inorder.UncheckedAt(j));
        polygon.SetVertex(++n,s->StartX(),s->StartY());
        all.Remove(s);
      }
      
      all.Compress();

      polygon.Close();
      
      contour->Add(polygon);
      
      if ( ! all.IsEmpty() )
      {
        i = 0;
        inorder.Clear();
        alreadyAdded.Set(all.GetLast()+1);
        alreadyAdded.Reset();
      }
      continue;
    }
    
    for ( Int_t j = 0; j <= all.GetLast(); ++j) 
    {
      if ( j != i && alreadyAdded[j] == 0 ) 
      {        
        const AliMUONSegment* sj = static_cast<const AliMUONSegment*>(all.UncheckedAt(j));
        if ( AliMUONSegment::AreEqual(si->EndX(),sj->StartX()) && AliMUONSegment::AreEqual(si->EndY(),sj->StartY()))
        {
          i = j;
          break;
        }
      }
    }    
  }
  
  contour->AssertOrientation(kTRUE);
  return contour;
}


//_____________________________________________________________________________
void 
AliMUONContourMaker::GetVerticalEdges(const TObjArray& polygons, TObjArray& polygonVerticalEdges) const
{
  /// From an array of polygons, extract the list of vertical edges.
  /// Output array polygonVerticalEdges should be empty before calling.
  
  AliCodeTimerAuto("",0);
  
  for ( Int_t i = 0; i <= polygons.GetLast(); ++i ) 
  {
    const AliMUONPolygon* g = static_cast<const AliMUONPolygon*>(polygons.UncheckedAt(i));
    for ( Int_t j = 0; j < g->NumberOfVertices()-1; ++j ) 
    {
      if ( AliMUONSegment::AreEqual(g->X(j),g->X(j+1)) ) // segment is vertical
      {
        polygonVerticalEdges.Add(new AliMUONSegment(g->X(j),g->Y(j),g->X(j+1),g->Y(j+1)));
      }
    }
  }
}


//_____________________________________________________________________________
void
AliMUONContourMaker::GetYPositions(const TObjArray& polygonVerticalEdges,
                                   TArrayD& yPositions) const
{
  /// Fill the array yPositions with the different y positions found in 
  /// polygonVerticalEdges
  
  AliCodeTimerAuto("",0);
  
  Double_t* y = new Double_t[polygonVerticalEdges.GetSize()*2];
  Int_t n(0);
  
  for ( Int_t i = 0; i < polygonVerticalEdges.GetLast(); ++i ) 
  {
    AliMUONSegment* s = static_cast<AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
    y[n] = s->StartY();
    y[n+1] = s->EndY();
    n += 2;
  }
  Int_t* ix = new Int_t[n+1];
  
  TMath::Sort(n,y,ix,kFALSE);
  
  yPositions.Set(n+1);
  
  Int_t u(0);
  Double_t x(FLT_MAX);
  
  for ( Int_t i = 0; i < n; ++i ) 
  {
    if ( y[ix[i]] != x )
    {
      yPositions[u] = y[ix[i]];
      x = y[ix[i]];
      ++u;
    }
  }

  yPositions.Set(u);
  
  delete[] ix;
  delete[] y;
  
}

//_____________________________________________________________________________
AliMUONContour* 
AliMUONContourMaker::MergeContour(const TObjArray& contours, const char* name) const
{
  /// Merge all the polygons of all contours into a single contour
  
  AliCodeTimerAuto("",0);
  
  TObjArray polygons;
  polygons.SetOwner(kTRUE);
  
  TIter next(&contours);
  AliMUONContour* contour;
  while ( ( contour = static_cast<AliMUONContour*>(next()) ) )
  {
    const TObjArray* contourPolygons = contour->Polygons();
    TIter nextPol(contourPolygons);
    AliMUONPolygon* pol;
    while ( ( pol = static_cast<AliMUONPolygon*>(nextPol()) ) )
    {
      polygons.Add(new AliMUONPolygon(*pol));
    }
  }
  
  if ( polygons.IsEmpty() ) return 0x0;
  
  contour = CreateContour(polygons,name);
  
  return contour;
}

//_____________________________________________________________________________
void 
AliMUONContourMaker::SortPoints(const TObjArray& polygonVerticalEdges, 
                                TObjArray& sortedPoints) const
{
  /// Sort the point of the vertical edges in ascending order, first on ordinate, 
  /// then on abcissa, and put them in output vector sortedPoints.
  /// Output array sortedPoints should be empty before calling this method.
  
  AliCodeTimerAuto("",0);
  
  for ( Int_t i = 0; i <= polygonVerticalEdges.GetLast(); ++i )
  {
    const AliMUONSegment* e = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
    sortedPoints.Add(new AliMUONPointWithRef(e->StartX(),e->StartY(),i));
    sortedPoints.Add(new AliMUONPointWithRef(e->EndX(),e->EndY(),i));
    // note that we keep track of the original edge, which is used
    // later on to deduce orientation of horizontal edges.
  }
  
  sortedPoints.Sort(); 
}

//_____________________________________________________________________________
void 
AliMUONContourMaker::Sweep(const TObjArray& polygonVerticalEdges, 
                           TObjArray& contourVerticalEdges) const
{
  /// This is the meat of the algorithm of the contour merging...
  
  AliCodeTimerAuto("",0);
  
  TArrayD yPositions;
  GetYPositions(polygonVerticalEdges,yPositions);
  
  AliMUONSegmentTree segmentTree(yPositions);
  
  for ( Int_t i = 0; i <= polygonVerticalEdges.GetLast(); ++i )
  {
    const AliMUONSegment* edge = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
    
    assert(edge!=0x0);
    
    if ( edge->IsLeftEdge() ) 
    {
      segmentTree.Contribution(edge->Bottom(),edge->Top());
      segmentTree.InsertInterval(edge->Bottom(),edge->Top());
    }
    else
    {
      segmentTree.DeleteInterval(edge->Bottom(),edge->Top());
      segmentTree.Contribution(edge->Bottom(),edge->Top());
    }
    
    AliMUONSegment e1(*edge);
    
    if ( i < polygonVerticalEdges.GetLast() ) 
    {
      const AliMUONSegment* next = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i+1));
      e1 = *next;
    }

    if ( ( edge->IsLeftEdge() != e1.IsLeftEdge() ) ||
        ( !AliMUONSegment::AreEqual(edge->StartX(),e1.StartX() ) ) ||
        ( i == polygonVerticalEdges.GetLast() ) )
    {
      const TObjArray& stack = segmentTree.Stack();
      
      double x = edge->StartX();
      
      for ( Int_t j = 0; j <= stack.GetLast(); ++j )
      {
        AliMUONSegment* sj = static_cast<AliMUONSegment*>(stack.UncheckedAt(j));
        AliMUONSegment* s = new AliMUONSegment(x,sj->StartY(),x,sj->EndY());
        
        if  (s->IsAPoint()) 
        {
          delete s;
          continue;
        }
        
        if ( edge->IsLeftEdge() != s->IsLeftEdge() ) 
        {
          s->Set(x,sj->EndY(),x,sj->StartY());
        }
        contourVerticalEdges.Add(s);
      }
      segmentTree.ResetStack();
    }
  }
}

//_____________________________________________________________________________
void 
AliMUONContourMaker::VerticalToHorizontal(const TObjArray& polygonVerticalEdges,
                                          TObjArray& horizontalEdges) const
{
  /// Deduce the set of horizontal edges from the vertical edges
  /// Output array horizontalEdges should be empty before calling this method
  
  AliCodeTimerAuto("",0);
  
  TObjArray points; // array of AliMUONPointWithRef
  points.SetOwner(kTRUE);
  
  SortPoints(polygonVerticalEdges,points);
  
  for ( Int_t k = 0; k < (points.GetLast()+1)/2; ++k )
  {
    const AliMUONPointWithRef* p1 = static_cast<AliMUONPointWithRef*>(points.UncheckedAt(k*2));
    const AliMUONPointWithRef* p2 = static_cast<AliMUONPointWithRef*>(points.UncheckedAt(k*2+1));
    
    const AliMUONSegment* refEdge = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(p1->Ref()));
    
    // (p1,p2) is the horizontal edge.
    // refEdge is used to deduce the orientation of (p1,p2)
    
    if ( AliMUONSegment::AreEqual(p1->X(),refEdge->EndX()) && AliMUONSegment::AreEqual(p1->Y(),refEdge->EndY()) )
//    if ( AreEqual(p1,refEdge->End()) )
    {
      horizontalEdges.Add(new AliMUONSegment(p1->X(),p1->Y(),p2->X(),p2->Y()));
    }
    else
    {
      horizontalEdges.Add(new AliMUONSegment(p2->X(),p2->Y(),p1->X(),p1->Y()));
    }
  }
}
Commit	Line	Data
0b936dc0	1	/**************************************************************************
	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
	15
	16	// $Id$
	17
	18	///
	19	/// Maker/merger of contours. Can create contour from a set polygons or
	20	/// merger a set of contours into a single one.
	21	///
	22	/// This is based on (one of the) algorithm found in
	23	/// Diane L. Souvaine and Iliana Bjorling-Sachs,
	24	/// Proceedings of the IEEE, Vol. 80, No. 9, September 1992, p. 1449
	25	///
	26	/// Note that besides the AliMUON prefix, nothing is really MUON specific
	27	/// in this class...
	28	///
	29	/// \author Laurent Aphecetche, Subatech
	30	///
	31
	32	#include "AliMUONContourMaker.h"
	33
	34	#include "AliCodeTimer.h"
	35	#include "AliLog.h"
	36	#include "AliMUONContour.h"
	37	#include "AliMUONPointWithRef.h"
	38	#include "AliMUONPolygon.h"
	39	#include "AliMUONSegment.h"
	40	#include "AliMUONSegmentTree.h"
	41	#include "Riostream.h"
	42	#include "TArrayD.h"
	43	#include "TMath.h"
	44	#include <cassert>
fef32488	45	#include "TArrayI.h"
0b936dc0	46
	47	/// \cond CLASSIMP
	48	ClassImp(AliMUONContourMaker)
	49	/// \endcond
	50
0b936dc0	51	//_____________________________________________________________________________
	52	AliMUONContourMaker::AliMUONContourMaker()
	53	{
cddcc1f3	54	/// Default constructor
0b936dc0	55	}
0b936dc0	56
cddcc1f3	57
0b936dc0	58	//_____________________________________________________________________________
	59	AliMUONContourMaker::~AliMUONContourMaker()
	60	{
cddcc1f3	61	/// Destructor
0b936dc0	62	}
	63
	64	//_____________________________________________________________________________
	65	AliMUONContour*
	66	AliMUONContourMaker::CreateContour(const TObjArray& polygons, const char* name) const
	67	{
	68	/// Create the contour of the polygon array
	69	/// and get back the intermediate verticals and horizontal segments
	70	/// both arrays are arrays of AliMUONSegment objects.
	71
99c136e1	72	AliCodeTimerAuto("",0);
0b936dc0	73
	74	if ( polygons.IsEmpty() ) return 0x0; // protection against user error...
	75
	76	// Sanity check : insure that all polygons are oriented counter-clockwise
	77	TIter next(&polygons);
	78	AliMUONPolygon* pol;
	79	while ( ( pol = static_cast<AliMUONPolygon*>(next()) ) )
	80	{
	81	if ( !pol->IsCounterClockwiseOriented() )
	82	{
	83	AliError(Form("Got a clockwise oriented polygon in CreateContour(%s). That's not OK !",name));
	84	StdoutToAliError(polygons.Print());
	85	return 0x0;
	86	}
	87	}
	88
	89	AliMUONContour* contour(0x0);
	90
	91	if ( polygons.GetLast() == 0 )
	92	{
dd0be8a7	93	AliCodeTimerAuto("Trivial case",1);
0b936dc0	94	contour = new AliMUONContour(name);
7da191b6	95	pol = static_cast<AliMUONPolygon*>(polygons.First());
0b936dc0	96	contour->Add(*pol);
	97	contour->AssertOrientation();
	98	return contour;
	99	}
	100
	101	TObjArray polygonVerticalEdges; // arrray of AliMUONSegment objects
	102	polygonVerticalEdges.SetOwner(kTRUE);
	103	// get vertical edges of input polygons
	104	GetVerticalEdges(polygons,polygonVerticalEdges);
	105
	106	// sort them in ascending x order
	107	// if same x, insure that left edges are before right edges
	108	// within same x, order by increasing bottommost y (see AliMUONSegment::Compare method)
	109	polygonVerticalEdges.Sort();
	110
	111	if ( polygonVerticalEdges.GetLast()+1 < 2 )
	112	{
0b936dc0	113	polygons.Print();
fc2293be	114	AliFatal(Form("Got too few edges here for createContour %s",name));
0b936dc0	115	}
	116
	117	// Find the vertical edges of the merged contour. This is the meat of the algorithm...
	118	TObjArray contourVerticalEdges;
	119	contourVerticalEdges.SetOwner(kTRUE);
	120	Sweep(polygonVerticalEdges,contourVerticalEdges);
	121
	122	TObjArray horizontals;
	123	horizontals.SetOwner(kTRUE);
	124	VerticalToHorizontal(contourVerticalEdges,horizontals);
	125
	126	contour = FinalizeContour(contourVerticalEdges,horizontals);
	127
	128	if ( contour && name ) contour->SetName(name);
	129
	130	return contour;
	131	}
	132
	133	//_____________________________________________________________________________
	134	AliMUONContour*
	135	AliMUONContourMaker::FinalizeContour(const TObjArray& verticals,
	136	const TObjArray& horizontals) const
	137	{
	138	/// For a list of vertical and horizontal edges, we build the final
	139	/// contour object.
	140
99c136e1	141	AliCodeTimerAuto("",0);
0b936dc0	142
	143	TObjArray all; // array of AliMUONSegment
	144	TObjArray inorder; // array of AliMUONSegment
	145
	146	all.SetOwner(kFALSE);
	147	inorder.SetOwner(kFALSE);
	148
	149	for ( Int_t i = 0; i <= verticals.GetLast(); ++i )
	150	{
	151	all.Add(verticals.UncheckedAt(i));
	152	all.Add(horizontals.UncheckedAt(i));
	153	}
fef32488	154
	155	TArrayI alreadyAdded(all.GetLast()+1);
	156	alreadyAdded.Reset();
0b936dc0	157
	158	Int_t i(0);
	159
	160	AliMUONContour* contour = new AliMUONContour;
	161
	162	int total(0);
	163
	164	while ( !all.IsEmpty() )
	165	{
	166	total++;
	167
	168	if ( total > 1000 )
	169	{
	170	AliError("Total 1000 reached !!!!");
	171	return 0x0;
	172	}
	173
	174	AliMUONSegment* si = static_cast<AliMUONSegment*>(all.UncheckedAt(i));
	175	inorder.Add(si);
fef32488	176	alreadyAdded[i] = 1;
0b936dc0	177	const AliMUONSegment* all0 = static_cast<const AliMUONSegment*>(all.First());
	178	if ( i != 0 && AliMUONSegment::AreEqual(si->EndX(),all0->StartX()) && AliMUONSegment::AreEqual(si->EndY(),all0->StartY()) )
	179	{
	180	Int_t n(-1);
	181
	182	AliMUONPolygon polygon(inorder.GetLast()+2);
	183
	184	// we got a cycle. Add it to the contour
	185	for ( Int_t j = 0; j <= inorder.GetLast(); ++j )
	186	{
	187	AliMUONSegment* s = static_cast<AliMUONSegment*>(inorder.UncheckedAt(j));
	188	polygon.SetVertex(++n,s->StartX(),s->StartY());
	189	all.Remove(s);
	190	}
	191
	192	all.Compress();
	193
	194	polygon.Close();
	195
	196	contour->Add(polygon);
	197
	198	if ( ! all.IsEmpty() )
	199	{
	200	i = 0;
	201	inorder.Clear();
fef32488	202	alreadyAdded.Set(all.GetLast()+1);
fef32488	203	alreadyAdded.Reset();
0b936dc0	204	}
	205	continue;
	206	}
	207
	208	for ( Int_t j = 0; j <= all.GetLast(); ++j)
	209	{
fef32488	210	if ( j != i && alreadyAdded[j] == 0 )
0b936dc0	211	{
	212	const AliMUONSegment* sj = static_cast<const AliMUONSegment*>(all.UncheckedAt(j));
	213	if ( AliMUONSegment::AreEqual(si->EndX(),sj->StartX()) && AliMUONSegment::AreEqual(si->EndY(),sj->StartY()))
	214	{
	215	i = j;
	216	break;
	217	}
	218	}
	219	}
	220	}
	221
	222	contour->AssertOrientation(kTRUE);
	223	return contour;
	224	}
	225
	226
	227	//_____________________________________________________________________________
	228	void
	229	AliMUONContourMaker::GetVerticalEdges(const TObjArray& polygons, TObjArray& polygonVerticalEdges) const
	230	{
	231	/// From an array of polygons, extract the list of vertical edges.
	232	/// Output array polygonVerticalEdges should be empty before calling.
	233
99c136e1	234	AliCodeTimerAuto("",0);
0b936dc0	235
	236	for ( Int_t i = 0; i <= polygons.GetLast(); ++i )
	237	{
	238	const AliMUONPolygon* g = static_cast<const AliMUONPolygon*>(polygons.UncheckedAt(i));
	239	for ( Int_t j = 0; j < g->NumberOfVertices()-1; ++j )
	240	{
	241	if ( AliMUONSegment::AreEqual(g->X(j),g->X(j+1)) ) // segment is vertical
	242	{
	243	polygonVerticalEdges.Add(new AliMUONSegment(g->X(j),g->Y(j),g->X(j+1),g->Y(j+1)));
	244	}
	245	}
	246	}
	247	}
	248
	249
	250	//_____________________________________________________________________________
	251	void
	252	AliMUONContourMaker::GetYPositions(const TObjArray& polygonVerticalEdges,
	253	TArrayD& yPositions) const
	254	{
	255	/// Fill the array yPositions with the different y positions found in
	256	/// polygonVerticalEdges
	257
99c136e1	258	AliCodeTimerAuto("",0);
0b936dc0	259
	260	Double_t* y = new Double_t[polygonVerticalEdges.GetSize()*2];
	261	Int_t n(0);
	262
	263	for ( Int_t i = 0; i < polygonVerticalEdges.GetLast(); ++i )
	264	{
	265	AliMUONSegment* s = static_cast<AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
	266	y[n] = s->StartY();
	267	y[n+1] = s->EndY();
	268	n += 2;
	269	}
	270	Int_t* ix = new Int_t[n+1];
	271
	272	TMath::Sort(n,y,ix,kFALSE);
	273
	274	yPositions.Set(n+1);
	275
	276	Int_t u(0);
	277	Double_t x(FLT_MAX);
	278
	279	for ( Int_t i = 0; i < n; ++i )
	280	{
	281	if ( y[ix[i]] != x )
	282	{
	283	yPositions[u] = y[ix[i]];
	284	x = y[ix[i]];
	285	++u;
	286	}
	287	}
	288
	289	yPositions.Set(u);
	290
	291	delete[] ix;
	292	delete[] y;
	293
	294	}
	295
	296	//_____________________________________________________________________________
	297	AliMUONContour*
	298	AliMUONContourMaker::MergeContour(const TObjArray& contours, const char* name) const
	299	{
	300	/// Merge all the polygons of all contours into a single contour
	301
99c136e1	302	AliCodeTimerAuto("",0);
0b936dc0	303
	304	TObjArray polygons;
	305	polygons.SetOwner(kTRUE);
	306
	307	TIter next(&contours);
	308	AliMUONContour* contour;
	309	while ( ( contour = static_cast<AliMUONContour*>(next()) ) )
	310	{
	311	const TObjArray* contourPolygons = contour->Polygons();
	312	TIter nextPol(contourPolygons);
	313	AliMUONPolygon* pol;
	314	while ( ( pol = static_cast<AliMUONPolygon*>(nextPol()) ) )
	315	{
	316	polygons.Add(new AliMUONPolygon(*pol));
	317	}
	318	}
	319
	320	if ( polygons.IsEmpty() ) return 0x0;
	321
	322	contour = CreateContour(polygons,name);
	323
	324	return contour;
	325	}
	326
	327	//_____________________________________________________________________________
	328	void
	329	AliMUONContourMaker::SortPoints(const TObjArray& polygonVerticalEdges,
	330	TObjArray& sortedPoints) const
	331	{
	332	/// Sort the point of the vertical edges in ascending order, first on ordinate,
	333	/// then on abcissa, and put them in output vector sortedPoints.
	334	/// Output array sortedPoints should be empty before calling this method.
	335
99c136e1	336	AliCodeTimerAuto("",0);
0b936dc0	337
	338	for ( Int_t i = 0; i <= polygonVerticalEdges.GetLast(); ++i )
	339	{
	340	const AliMUONSegment* e = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
	341	sortedPoints.Add(new AliMUONPointWithRef(e->StartX(),e->StartY(),i));
	342	sortedPoints.Add(new AliMUONPointWithRef(e->EndX(),e->EndY(),i));
	343	// note that we keep track of the original edge, which is used
	344	// later on to deduce orientation of horizontal edges.
	345	}
	346
	347	sortedPoints.Sort();
	348	}
	349
	350	//_____________________________________________________________________________
	351	void
	352	AliMUONContourMaker::Sweep(const TObjArray& polygonVerticalEdges,
	353	TObjArray& contourVerticalEdges) const
	354	{
	355	/// This is the meat of the algorithm of the contour merging...
	356
99c136e1	357	AliCodeTimerAuto("",0);
0b936dc0	358
	359	TArrayD yPositions;
	360	GetYPositions(polygonVerticalEdges,yPositions);
	361
	362	AliMUONSegmentTree segmentTree(yPositions);
	363
	364	for ( Int_t i = 0; i <= polygonVerticalEdges.GetLast(); ++i )
	365	{
	366	const AliMUONSegment* edge = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i));
	367
	368	assert(edge!=0x0);
	369
	370	if ( edge->IsLeftEdge() )
	371	{
	372	segmentTree.Contribution(edge->Bottom(),edge->Top());
	373	segmentTree.InsertInterval(edge->Bottom(),edge->Top());
	374	}
	375	else
	376	{
	377	segmentTree.DeleteInterval(edge->Bottom(),edge->Top());
	378	segmentTree.Contribution(edge->Bottom(),edge->Top());
	379	}
	380
	381	AliMUONSegment e1(*edge);
	382
	383	if ( i < polygonVerticalEdges.GetLast() )
	384	{
	385	const AliMUONSegment* next = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(i+1));
	386	e1 = *next;
	387	}
	388
	389	if ( ( edge->IsLeftEdge() != e1.IsLeftEdge() ) \|\|
	390	( !AliMUONSegment::AreEqual(edge->StartX(),e1.StartX() ) ) \|\|
	391	( i == polygonVerticalEdges.GetLast() ) )
	392	{
	393	const TObjArray& stack = segmentTree.Stack();
	394
	395	double x = edge->StartX();
	396
	397	for ( Int_t j = 0; j <= stack.GetLast(); ++j )
	398	{
	399	AliMUONSegment* sj = static_cast<AliMUONSegment*>(stack.UncheckedAt(j));
	400	AliMUONSegment* s = new AliMUONSegment(x,sj->StartY(),x,sj->EndY());
	401
	402	if (s->IsAPoint())
	403	{
	404	delete s;
	405	continue;
	406	}
	407
	408	if ( edge->IsLeftEdge() != s->IsLeftEdge() )
	409	{
	410	s->Set(x,sj->EndY(),x,sj->StartY());
	411	}
	412	contourVerticalEdges.Add(s);
	413	}
	414	segmentTree.ResetStack();
	415	}
	416	}
	417	}
	418
	419	//_____________________________________________________________________________
	420	void
	421	AliMUONContourMaker::VerticalToHorizontal(const TObjArray& polygonVerticalEdges,
422	TObjArray& horizontalEdges) const
423	{
424	/// Deduce the set of horizontal edges from the vertical edges
425	/// Output array horizontalEdges should be empty before calling this method
426
99c136e1	427	AliCodeTimerAuto("",0);
0b936dc0	428
	429	TObjArray points; // array of AliMUONPointWithRef
	430	points.SetOwner(kTRUE);
	431
	432	SortPoints(polygonVerticalEdges,points);
	433
	434	for ( Int_t k = 0; k < (points.GetLast()+1)/2; ++k )
	435	{
	436	const AliMUONPointWithRef* p1 = static_cast<AliMUONPointWithRef>(points.UncheckedAt(k2));
	437	const AliMUONPointWithRef* p2 = static_cast<AliMUONPointWithRef>(points.UncheckedAt(k2+1));
	438
	439	const AliMUONSegment* refEdge = static_cast<const AliMUONSegment*>(polygonVerticalEdges.UncheckedAt(p1->Ref()));
	440
	441	// (p1,p2) is the horizontal edge.
	442	// refEdge is used to deduce the orientation of (p1,p2)
	443
	444	if ( AliMUONSegment::AreEqual(p1->X(),refEdge->EndX()) && AliMUONSegment::AreEqual(p1->Y(),refEdge->EndY()) )
	445	// if ( AreEqual(p1,refEdge->End()) )
	446	{
	447	horizontalEdges.Add(new AliMUONSegment(p1->X(),p1->Y(),p2->X(),p2->Y()));
	448	}
	449	else
	450	{
	451	horizontalEdges.Add(new AliMUONSegment(p2->X(),p2->Y(),p1->X(),p1->Y()));
	452	}
	453	}
	454	}
	455