/*=========================================================================

  Program:   Visualization Toolkit
  Module:    $RCSfile: vtkPolyData.cxx,v $
  Language:  C++
  Date:      $Date: 2003/04/15 08:16:55 $
  Version:   $Revision: 1.154 $

  Copyright (c) 1993-2002 Ken Martin, Will Schroeder, Bill Lorensen 
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even 
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "vtkPolyData.h"

#include "vtkCellArray.h"
#include "vtkCellData.h"
#include "vtkCriticalSection.h"
#include "vtkEmptyCell.h"
#include "vtkGenericCell.h"
#include "vtkLine.h"
#include "vtkObjectFactory.h"
#include "vtkPointData.h"
#include "vtkPointLocator.h"
#include "vtkPolyLine.h"
#include "vtkPolyVertex.h"
#include "vtkPolygon.h"
#include "vtkQuad.h"
#include "vtkTriangle.h"
#include "vtkTriangleStrip.h"
#include "vtkVertex.h"

vtkCxxRevisionMacro(vtkPolyData, "$Revision: 1.154 $");
vtkStandardNewMacro(vtkPolyData);

//----------------------------------------------------------------------------
// Initialize static member.  This member is used to simplify traversal
// of verts, lines, polygons, and triangle strips lists.  It basically 
// "marks" empty lists so that the traveral method "GetNextCell" 
// works properly.
vtkCellArray *vtkPolyData::Dummy = NULL;

static vtkSimpleCriticalSection DummyCritSect;

vtkPolyData::vtkPolyData ()
{
  // Create these guys only when needed. This saves a huge amount
  // of memory and time spent in memory allocation.
  this->Vertex = NULL;
  this->PolyVertex = NULL;
  this->Line = NULL;
  this->PolyLine = NULL;
  this->Triangle = NULL;
  this->Quad = NULL;
  this->Polygon = NULL;
  this->TriangleStrip = NULL;
  this->EmptyCell = NULL;
  
  this->Verts = NULL;
  this->Lines = NULL;
  this->Polys = NULL;
  this->Strips = NULL;

  // static variable, initialized only once.
  DummyCritSect.Lock();
  if (this->Dummy == NULL) 
    {
    this->Dummy = vtkCellArray::New();
    this->Dummy->Register(this);
    this->Dummy->Delete();
    }
  else
    {
    this->Dummy->Register(this);
    }
  DummyCritSect.Unlock();

  this->Cells = NULL;
  this->Links = NULL;
}

//----------------------------------------------------------------------------
vtkPolyData::~vtkPolyData()
{
  vtkPolyData::Initialize();
  // Reference to static dummy persists. 
  // Keep destructed dummy from being used again.
  DummyCritSect.Lock();
  if (this->Dummy->GetReferenceCount() == 1)
    {
    this->Dummy->UnRegister(this);
    this->Dummy = NULL;
    }
  else
    {
    this->Dummy->UnRegister(this);
    }
  DummyCritSect.Unlock();

  if (this->Vertex)
    {
    this->Vertex->Delete();
    }

  if (this->PolyVertex)
    {
    this->PolyVertex->Delete();
    }

  if (this->Line)
    {
    this->Line->Delete();
    }

  if (this->PolyLine)
    {
    this->PolyLine->Delete();
    }

  if (this->Triangle)
    {
    this->Triangle->Delete();
    }
  
  if (this->Quad)
    {
    this->Quad->Delete();
    }

  if (this->Polygon)
    {
    this->Polygon->Delete();
    }

  if (this->TriangleStrip)
    {
    this->TriangleStrip->Delete();
    }

  if (this->EmptyCell)
    {
    this->EmptyCell->Delete();
    }
}

//----------------------------------------------------------------------------
// Copy the geometric and topological structure of an input poly data object.
void vtkPolyData::CopyStructure(vtkDataSet *ds)
{
  vtkPolyData *pd=(vtkPolyData *)ds;
  vtkPointSet::CopyStructure(ds);

  this->Verts = pd->Verts;
  if (this->Verts)
    {
    this->Verts->Register(this);
    }

  this->Lines = pd->Lines;
  if (this->Lines)
    {
    this->Lines->Register(this);
    }

  this->Polys = pd->Polys;
  if (this->Polys)
    {
    this->Polys->Register(this);
    }

  this->Strips = pd->Strips;
  if (this->Strips)
    {
    this->Strips->Register(this);
    }
}

//----------------------------------------------------------------------------
int vtkPolyData::GetCellType(vtkIdType cellId)
{
  if ( !this->Cells )
    {
    this->BuildCells();
    }
  return this->Cells->GetCellType(cellId);
}

//----------------------------------------------------------------------------
vtkCell *vtkPolyData::GetCell(vtkIdType cellId)
{
  int i, loc;
  vtkIdType *pts, numPts;
  vtkCell *cell = NULL;
  unsigned char type;

  if ( !this->Cells )
    {
    this->BuildCells();
    }

  type = this->Cells->GetCellType(cellId);
  loc = this->Cells->GetCellLocation(cellId);

  switch (type)
    {
    case VTK_VERTEX:
      if (!this->Vertex)
        {
        this->Vertex = vtkVertex::New();
        }
      cell = this->Vertex;
      this->Verts->GetCell(loc,numPts,pts);
      break;

    case VTK_POLY_VERTEX:
      if (! this->PolyVertex)
        {
        this->PolyVertex = vtkPolyVertex::New();
        }
      cell = this->PolyVertex;
      this->Verts->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_LINE: 
      if (! this->Line )
        {
        this->Line = vtkLine::New();
        }
      cell = this->Line;
      this->Lines->GetCell(loc,numPts,pts);
      break;

    case VTK_POLY_LINE:
      if (!this->PolyLine)
        {
        this->PolyLine = vtkPolyLine::New();
        }
      cell = this->PolyLine;
      this->Lines->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_TRIANGLE:
      if (!this->Triangle)
        {
        this->Triangle = vtkTriangle::New();
        }
      cell = this->Triangle;
      this->Polys->GetCell(loc,numPts,pts);
      break;

    case VTK_QUAD:
      if (!this->Quad)
        {
        this->Quad = vtkQuad::New();
        }
      cell = this->Quad;
      this->Polys->GetCell(loc,numPts,pts);
      break;

    case VTK_POLYGON:
      if (!this->Polygon)
        {
        this->Polygon = vtkPolygon::New();
        }
      cell = this->Polygon;
      this->Polys->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_TRIANGLE_STRIP:
      if (!this->TriangleStrip)
        {
        this->TriangleStrip = vtkTriangleStrip::New();
        }
      cell = this->TriangleStrip;
      this->Strips->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    default:
      if (!this->EmptyCell)
        {
        this->EmptyCell = vtkEmptyCell::New();
        }
      cell = this->EmptyCell;
      numPts = 0;
      return cell;
    }

  for (i=0; i < numPts; i++)
    {
    cell->PointIds->SetId(i,pts[i]);
    cell->Points->SetPoint(i,this->Points->GetPoint(pts[i]));
    }

  return cell;
}

//----------------------------------------------------------------------------
void vtkPolyData::GetCell(vtkIdType cellId, vtkGenericCell *cell)
{
  int             i, loc;
  vtkIdType       *pts=0;
  vtkIdType       numPts;
  unsigned char   type;
  float           x[3];

  if ( !this->Cells )
    {
    this->BuildCells();
    }

  type = this->Cells->GetCellType(cellId);
  loc = this->Cells->GetCellLocation(cellId);

  switch (type)
    {
    case VTK_VERTEX:
      cell->SetCellTypeToVertex();
      this->Verts->GetCell(loc,numPts,pts);
      break;

    case VTK_POLY_VERTEX:
      cell->SetCellTypeToPolyVertex();
      this->Verts->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_LINE: 
      cell->SetCellTypeToLine();
      this->Lines->GetCell(loc,numPts,pts);
      break;

    case VTK_POLY_LINE:
      cell->SetCellTypeToPolyLine();
      this->Lines->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_TRIANGLE:
      cell->SetCellTypeToTriangle();
      this->Polys->GetCell(loc,numPts,pts);
      break;

    case VTK_QUAD:
      cell->SetCellTypeToQuad();
      this->Polys->GetCell(loc,numPts,pts);
      break;

    case VTK_POLYGON:
      cell->SetCellTypeToPolygon();
      this->Polys->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    case VTK_TRIANGLE_STRIP:
      cell->SetCellTypeToTriangleStrip();
      this->Strips->GetCell(loc,numPts,pts);
      cell->PointIds->SetNumberOfIds(numPts); //reset number of points
      cell->Points->SetNumberOfPoints(numPts);
      break;

    default:
      cell->SetCellTypeToEmptyCell();
      numPts = 0;
    }

  for (i=0; i < numPts; i++)
    {
    cell->PointIds->SetId(i,pts[i]);
    this->Points->GetPoint(pts[i], x);
    cell->Points->SetPoint(i, x);
    }
}

void vtkPolyData::CopyCells(vtkPolyData *pd, vtkIdList *idList,
                            vtkPointLocator *locator)
{
  vtkIdType cellId, ptId, newId, newCellId, locatorPtId;
  int numPts, numCellPts, i;
  vtkPoints *newPoints;
  vtkIdList *pointMap = vtkIdList::New(); //maps old pt ids into new
  vtkIdList *cellPts, *newCellPts = vtkIdList::New();
  vtkGenericCell *cell = vtkGenericCell::New();
  float x[3];
  vtkPointData *outPD = this->GetPointData();
  vtkCellData *outCD = this->GetCellData();
  
  numPts = pd->GetNumberOfPoints();

  if (this->GetPoints() == NULL)
    {
    this->Points = vtkPoints::New();
    }
  
  newPoints = this->GetPoints();
  
  pointMap->SetNumberOfIds(numPts);
  for (i=0; i < numPts; i++)
    {
    pointMap->SetId(i,-1);
    }

  // Filter the cells
  for (cellId=0; cellId < idList->GetNumberOfIds(); cellId++)
    {
    pd->GetCell(idList->GetId(cellId), cell);
    cellPts = cell->GetPointIds();
    numCellPts = cell->GetNumberOfPoints();
    
    for (i=0; i < numCellPts; i++)
      {
      ptId = cellPts->GetId(i);
      if ( (newId = pointMap->GetId(ptId)) < 0 )
        {
        pd->GetPoint(ptId, x);
        if (locator != NULL)
          {
          if ((locatorPtId = locator->IsInsertedPoint(x)) == -1)
            {
            newId = newPoints->InsertNextPoint(x);
            locator->InsertNextPoint(x);
            pointMap->SetId(ptId, newId);
            outPD->CopyData(pd->GetPointData(), ptId, newId);
            }
          else
            {
            newId = locatorPtId;
            }
          }
        else
          {
          newId = newPoints->InsertNextPoint(x);
          pointMap->SetId(ptId, newId);
          outPD->CopyData(pd->GetPointData(), ptId, newId);
          }
        }
      newCellPts->InsertId(i,newId);
      }
    newCellId = this->InsertNextCell(cell->GetCellType(), newCellPts);
    outCD->CopyData(pd->GetCellData(), idList->GetId(cellId), newCellId);
    newCellPts->Reset();
    } // for all cells
  newCellPts->Delete();
  pointMap->Delete();
  cell->Delete();
}

//----------------------------------------------------------------------------
// Fast implementation of GetCellBounds().  Bounds are calculated without
// constructing a cell.
void vtkPolyData::GetCellBounds(vtkIdType cellId, float bounds[6])
{
  int i, loc;
  vtkIdType *pts, numPts;
  unsigned char type;
  float x[3];

  if ( !this->Cells )
    {
    this->BuildCells();
    }

  type = this->Cells->GetCellType(cellId);
  loc = this->Cells->GetCellLocation(cellId);

  switch (type)
    {
    case VTK_VERTEX:
    case VTK_POLY_VERTEX:
      this->Verts->GetCell(loc,numPts,pts);
      break;

    case VTK_LINE: 
    case VTK_POLY_LINE:
      this->Lines->GetCell(loc,numPts,pts);
      break;

    case VTK_TRIANGLE:
    case VTK_QUAD:
    case VTK_POLYGON:
      this->Polys->GetCell(loc,numPts,pts);
      break;

    case VTK_TRIANGLE_STRIP:
      this->Strips->GetCell(loc,numPts,pts);
      break;

    default:
      bounds[0] = bounds[1] = bounds[2] = bounds[3] = bounds[4] = bounds[5]
        = 0.0;
      return;
    }

  bounds[0] = bounds[2] = bounds[4] =  VTK_LARGE_FLOAT;
  bounds[1] = bounds[3] = bounds[5] = -VTK_LARGE_FLOAT;

  for (i=0; i < numPts; i++)
    {
    this->Points->GetPoint( pts[i], x );

    if (x[0] < bounds[0])
      {
      bounds[0] = x[0];
      }
    if (x[0] > bounds[1])
      {
      bounds[1] = x[0];
      }
    if (x[1] < bounds[2])
      {
      bounds[2] = x[1];
      }
    if (x[1] > bounds[3])
      {
      bounds[3] = x[1];
      }
    if (x[2] < bounds[4])
      {
      bounds[4] = x[2];
      }
    if (x[2] > bounds[5])
      {
      bounds[5] = x[2];
      }
    }
}


//----------------------------------------------------------------------------
void vtkPolyData::ComputeBounds()
{
  if (this->GetMTime() > this->ComputeTime)
    {
    // If there are no cells, but there are points, back to the
    // bounds of the points set.
    if (this->GetNumberOfCells() == 0 && this->GetNumberOfPoints()) 
      {
      vtkPointSet::ComputeBounds();
      return;
      } 

    int t, i;
    vtkIdType *pts = 0;
    vtkIdType npts = 0;
    float x[3];

    this->Bounds[0] = this->Bounds[2] = this->Bounds[4] =  VTK_LARGE_FLOAT;
    this->Bounds[1] = this->Bounds[3] = this->Bounds[5] = -VTK_LARGE_FLOAT;

    vtkCellArray *cella[4];

    cella[0] = this->GetVerts();
    cella[1] = this->GetLines();
    cella[2] = this->GetPolys();
    cella[3] = this->GetStrips();

    // Iterate over cells's points
    for (t = 0; t < 4; t++) 
      {
      for (cella[t]->InitTraversal(); cella[t]->GetNextCell(npts,pts); )
        {
        for (i = 0;  i < npts; i++)
          {
          this->Points->GetPoint( pts[i], x );

          if (x[0] < this->Bounds[0])
            {
            this->Bounds[0] = x[0];
            }
          if (x[0] > this->Bounds[1])
            {
            this->Bounds[1] = x[0];
            }
          if (x[1] < this->Bounds[2])
            {
            this->Bounds[2] = x[1];
            }
          if (x[1] > this->Bounds[3])
            {
            this->Bounds[3] = x[1];
            }
          if (x[2] < this->Bounds[4])
            {
            this->Bounds[4] = x[2];
            }
          if (x[2] > this->Bounds[5])
            {
            this->Bounds[5] = x[2];
            }
          }
        }
      }

    this->ComputeTime.Modified();
    }
}

//----------------------------------------------------------------------------
// Set the cell array defining vertices.
void vtkPolyData::SetVerts (vtkCellArray* v) 
{
  if (v == this->Dummy)
    {
    v = NULL;
    }
  if ( v != this->Verts)
    {
    if (this->Verts)
      {
      this->Verts->UnRegister(this);
      }
    this->Verts = v;
    if (this->Verts)
      {
      this->Verts->Register(this);
      }
    this->Modified();
    }
}

//----------------------------------------------------------------------------
// Get the cell array defining vertices. If there are no vertices, an
// empty array will be returned (convenience to simplify traversal).
vtkCellArray* vtkPolyData::GetVerts()
{
  if ( !this->Verts )
    {
    return this->Dummy;
    }
  else
    {
    return this->Verts;
    }
}

//----------------------------------------------------------------------------
// Set the cell array defining lines.
void vtkPolyData::SetLines (vtkCellArray* l) 
{
  if (l == this->Dummy)
    {
    l = NULL;
    }
  if ( l != this->Lines)
    {
    if (this->Lines)
      {
      this->Lines->UnRegister(this);
      }
    this->Lines = l;
    if (this->Lines)
      {
      this->Lines->Register(this);
      }
    this->Modified();
    }
}

//----------------------------------------------------------------------------
// Get the cell array defining lines. If there are no lines, an
// empty array will be returned (convenience to simplify traversal).
vtkCellArray* vtkPolyData::GetLines()
{
  if ( !this->Lines )
    {
    return this->Dummy;
    }
  else
    {
    return this->Lines;
    }
}

//----------------------------------------------------------------------------
// Set the cell array defining polygons.
void vtkPolyData::SetPolys (vtkCellArray* p) 
{
  if(p == this->Dummy) 
    {
    p = NULL;
    }
  if ( p != this->Polys)
    {
    if (this->Polys)
      {
      this->Polys->UnRegister(this);
      }
    this->Polys = p;
    if (this->Polys)
      {
      this->Polys->Register(this);
      }
    this->Modified();
    }
}

//----------------------------------------------------------------------------
// Get the cell array defining polygons. If there are no polygons, an
// empty array will be returned (convenience to simplify traversal).
vtkCellArray* vtkPolyData::GetPolys()
{
  if ( !this->Polys )
    {
    return this->Dummy;
    }
  else
    {
    return this->Polys;
    }
}

//----------------------------------------------------------------------------
// Set the cell array defining triangle strips.
void vtkPolyData::SetStrips (vtkCellArray* s) 
{
  if ( s == this->Dummy)
    {
    s = NULL;
    }
  if ( s != this->Strips)
    {
    if (this->Strips)
      {
      this->Strips->UnRegister(this);
      }
    this->Strips = s;
    if (this->Strips)
      {
      this->Strips->Register(this);
      }
    this->Modified();
    }
}

//----------------------------------------------------------------------------
// Get the cell array defining triangle strips. If there are no
// triangle strips, an empty array will be returned (convenience to 
// simplify traversal).
vtkCellArray* vtkPolyData::GetStrips()
{
  if ( !this->Strips )
    {
    return this->Dummy;
    }
  else
    {
    return this->Strips;
    }
}

//----------------------------------------------------------------------------
// Restore object to initial state. Release memory back to system.
void vtkPolyData::Initialize()
{
  vtkPointSet::Initialize();

  if ( this->Verts ) 
    {
    this->Verts->UnRegister(this);
    this->Verts = NULL;
    }

  if ( this->Lines ) 
    {
    this->Lines->UnRegister(this);
    this->Lines = NULL;
    }

  if ( this->Polys ) 
    {
    this->Polys->UnRegister(this);
    this->Polys = NULL;
    }

  if ( this->Strips ) 
    {
    this->Strips->UnRegister(this);
    this->Strips = NULL;
    }

  if ( this->Cells )
    {
    this->Cells->UnRegister(this);
    this->Cells = NULL;
    }

  if ( this->Links )
    {
    this->Links->UnRegister(this);
    this->Links = NULL;
    }
}

//----------------------------------------------------------------------------
int vtkPolyData::GetMaxCellSize() 
{
  int maxCellSize=0, cellSize;

  if ( this->Verts ) 
    {
    cellSize = this->Verts->GetMaxCellSize();
    if ( cellSize > maxCellSize )
      {
      maxCellSize = cellSize;
      }
    }

  if ( this->Lines ) 
    {
    cellSize = this->Lines->GetMaxCellSize();
    if ( cellSize > maxCellSize )
      {
      maxCellSize = cellSize;
      }
    }

  if ( this->Polys ) 
    {
    cellSize = this->Polys->GetMaxCellSize();
    if ( cellSize > maxCellSize )
      {
      maxCellSize = cellSize;
      }
    }

  if ( this->Strips ) 
    {
    cellSize = this->Strips->GetMaxCellSize();
    if ( cellSize > maxCellSize )
      {
      maxCellSize = cellSize;
      }
    }

  return maxCellSize;
}

//----------------------------------------------------------------------------
vtkIdType vtkPolyData::GetNumberOfCells() 
{
  return this->GetNumberOfVerts() + this->GetNumberOfLines() + 
         this->GetNumberOfPolys() + this->GetNumberOfStrips();
}

//----------------------------------------------------------------------------
vtkIdType vtkPolyData::GetNumberOfVerts() 
{
  return (this->Verts ? this->Verts->GetNumberOfCells() : 0);
}

vtkIdType vtkPolyData::GetNumberOfLines() 
{
  return (this->Lines ? this->Lines->GetNumberOfCells() : 0);
}

vtkIdType vtkPolyData::GetNumberOfPolys() 
{
  return (this->Polys ? this->Polys->GetNumberOfCells() : 0);
}

vtkIdType vtkPolyData::GetNumberOfStrips() 
{
  return (this->Strips ? this->Strips->GetNumberOfCells() : 0);
}


//----------------------------------------------------------------------------
void vtkPolyData::DeleteCells()
{
  // if we have Links, we need to delete them (they are no longer valid)
  if (this->Links)
    {
    this->Links->UnRegister( this );
    this->Links = NULL;
    }
   
  if (this->Cells)
    {
    this->Cells->UnRegister( this );
    this->Cells = NULL;
    }
}

//----------------------------------------------------------------------------
// Create data structure that allows random access of cells.
void vtkPolyData::BuildCells()
{
  vtkIdType numCells;
  vtkCellArray *inVerts=this->GetVerts();
  vtkCellArray *inLines=this->GetLines();
  vtkCellArray *inPolys=this->GetPolys();
  vtkCellArray *inStrips=this->GetStrips();
  vtkIdType npts=0;
  vtkIdType *pts=0;
  vtkCellTypes *cells;

  vtkDebugMacro (<< "Building PolyData cells.");

  if ( (numCells = this->GetNumberOfCells()) < 1 )
    {
    numCells = 1000; //may be allocating empty list to begin with
    }

  if (this->Cells)
    {
    this->DeleteCells();
    }
  
  this->Cells = cells = vtkCellTypes::New();
  this->Cells->Allocate(numCells,3*numCells);
  this->Cells->Register(this);
  cells->Delete();
  //
  // Traverse various lists to create cell array
  //
  for (inVerts->InitTraversal(); inVerts->GetNextCell(npts,pts); )
    {
    if ( npts > 1 )
      {
      cells->InsertNextCell(VTK_POLY_VERTEX,
                            inVerts->GetTraversalLocation(npts));
      }
    else
      {
      cells->InsertNextCell(VTK_VERTEX,inVerts->GetTraversalLocation(npts));
      }
    }

  for (inLines->InitTraversal(); inLines->GetNextCell(npts,pts); )
    {
    if ( npts > 2 )
      {
      cells->InsertNextCell(VTK_POLY_LINE,inLines->GetTraversalLocation(npts));
      }
    else
      {
      cells->InsertNextCell(VTK_LINE,inLines->GetTraversalLocation(npts));
      } 
    }

  for (inPolys->InitTraversal(); inPolys->GetNextCell(npts,pts); )
    {
    if ( npts == 3 )
      {
      cells->InsertNextCell(VTK_TRIANGLE,inPolys->GetTraversalLocation(npts));
      }
    else if ( npts == 4 )
      {
      cells->InsertNextCell(VTK_QUAD,inPolys->GetTraversalLocation(npts));
      }
    else
      {
      cells->InsertNextCell(VTK_POLYGON,inPolys->GetTraversalLocation(npts));
      }
    }

  for (inStrips->InitTraversal(); inStrips->GetNextCell(npts,pts); )
    {
    cells->InsertNextCell(VTK_TRIANGLE_STRIP,
                          inStrips->GetTraversalLocation(npts));
    }
}

//----------------------------------------------------------------------------
void vtkPolyData::DeleteLinks()
{
  if (this->Links)
    {
    this->Links->UnRegister( this );
    this->Links = NULL;
    }
}

//----------------------------------------------------------------------------
// Create upward links from points to cells that use each point. Enables
// topologically complex queries.
void vtkPolyData::BuildLinks(int initialSize)
{
  if ( this->Links )
    {
    this->DeleteLinks();
    }
  
  if ( this->Cells == NULL )
    {
    this->BuildCells();
    }

  this->Links = vtkCellLinks::New();
  if ( initialSize > 0 )
    {
    this->Links->Allocate(initialSize);
    }
  else
    {
    this->Links->Allocate(this->GetNumberOfPoints());
    }
  this->Links->Register(this);
  this->Links->Delete();

  this->Links->BuildLinks(this);
}

//----------------------------------------------------------------------------
// Copy a cells point ids into list provided. (Less efficient.)
void vtkPolyData::GetCellPoints(vtkIdType cellId, vtkIdList *ptIds)
{
  vtkIdType i;
  vtkIdType *pts, npts;
  
  ptIds->Reset();
  if ( this->Cells == NULL )
    {
    this->BuildCells();
    }

  this->vtkPolyData::GetCellPoints(cellId, npts, pts);
  ptIds->InsertId (npts-1,pts[npts-1]);
  for (i=0; i<npts-1; i++)
    {
    ptIds->SetId(i,pts[i]);
    }
}

//----------------------------------------------------------------------------
// Return a pointer to a list of point ids defining cell. (More efficient.)
// Assumes that cells have been built (with BuildCells()).
void vtkPolyData::GetCellPoints(vtkIdType cellId, vtkIdType& npts,
                                vtkIdType* &pts)
{
  int loc;
  unsigned char type;

  type = this->Cells->GetCellType(cellId);
  loc = this->Cells->GetCellLocation(cellId);

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
      this->Verts->GetCell(loc,npts,pts);
      break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->GetCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->GetCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE_STRIP:
      this->Strips->GetCell(loc,npts,pts);
      break;

    default:
      npts = 0;
      pts = NULL;
    }
}

//----------------------------------------------------------------------------
void vtkPolyData::GetPointCells(vtkIdType ptId, vtkIdList *cellIds)
{
  vtkIdType *cells;
  vtkIdType numCells;
  vtkIdType i;

  if ( ! this->Links )
    {
    this->BuildLinks();
    }
  cellIds->Reset();

  numCells = this->Links->GetNcells(ptId);
  cells = this->Links->GetCells(ptId);

  for (i=0; i < numCells; i++)
    {
    cellIds->InsertId(i,cells[i]);
    }
}

//----------------------------------------------------------------------------
// Method allocates initial storage for vertex, line, polygon, and 
// triangle strip arrays. Use this method before the method 
// PolyData::InsertNextCell(). (Or, provide vertex, line, polygon, and
// triangle strip cell arrays.)
void vtkPolyData::Allocate(vtkIdType numCells, int extSize)
{
  vtkCellArray *cells;

  if (!this->Cells)
    {
    this->Cells = vtkCellTypes::New();
    this->Cells->Allocate(numCells,3*numCells);
    // Consistent Register/UnRegister. (ShallowCopy).
    this->Cells->Register(this);
    this->Cells->Delete();
    }

  cells = vtkCellArray::New();
  cells->Allocate(numCells,extSize);
  this->SetVerts(cells);
  cells->Delete();

  cells = vtkCellArray::New();
  cells->Allocate(numCells,extSize);
  this->SetLines(cells);
  cells->Delete();

  cells = vtkCellArray::New();
  cells->Allocate(numCells,extSize);
  this->SetPolys(cells);
  cells->Delete();

  cells = vtkCellArray::New();
  cells->Allocate(numCells,extSize);
  this->SetStrips(cells);
  cells->Delete();
}

void vtkPolyData::Allocate(vtkPolyData *inPolyData, vtkIdType numCells, 
                           int extSize)
{
  vtkCellArray *cells;
  int numVerts=inPolyData->GetVerts()->GetNumberOfCells();
  int numLines=inPolyData->GetLines()->GetNumberOfCells();
  int numPolys=inPolyData->GetPolys()->GetNumberOfCells();
  int numStrips=inPolyData->GetStrips()->GetNumberOfCells();
  int total=numVerts+numLines+numPolys+numStrips;

  if ( total <= 0 )
    {
    return;
    }
  
  if (!this->Cells)
    {
    this->Cells = vtkCellTypes::New();
    this->Cells->Allocate(numCells,3*numCells);
    // Consistent Register/UnRegister. (ShallowCopy).
    this->Cells->Register(this);
    this->Cells->Delete();
    }

  if ( numVerts > 0 )
    {
    cells = vtkCellArray::New();
    cells->Allocate((int)((float)numVerts/total*numCells),extSize);
    this->SetVerts(cells);
    cells->Delete();
    }
  if ( numLines > 0 )
    {
    cells = vtkCellArray::New();
    cells->Allocate((int)((float)numLines/total*numCells),extSize);
    this->SetLines(cells);
    cells->Delete();
    }
  if ( numPolys > 0 )
    {
    cells = vtkCellArray::New();
    cells->Allocate((int)((float)numPolys/total*numCells),extSize);
    this->SetPolys(cells);
    cells->Delete();
    }
  if ( numStrips > 0 )
    {
    cells = vtkCellArray::New();
    cells->Allocate((int)((float)numStrips/total*numCells),extSize);
    this->SetStrips(cells);
    cells->Delete();
    }
}

//----------------------------------------------------------------------------
// Insert a cell of type vtkVERTEX, vtkPOLY_VERTEX, vtkLINE, vtkPOLY_LINE,
// vtkTRIANGLE, vtkQUAD, vtkPOLYGON, or vtkTRIANGLE_STRIP.  Make sure that
// the PolyData::Allocate() function has been called first or that vertex,
// line, polygon, and triangle strip arrays have been supplied.
// Note: will also insert vtkPIXEL, but converts it to vtkQUAD.
int vtkPolyData::InsertNextCell(int type, int npts, vtkIdType *pts)
{
  int id;

  if ( !this->Cells ) 
    {
    // if we get to this point, the user has not made any guess at the
    // number of cells, so this guess is as good as any
    this->Cells = vtkCellTypes::New();
    this->Cells->Allocate(5000,10000);
    }

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
      this->Verts->InsertNextCell(npts,pts);
      id = this->Cells->InsertNextCell(type, 
                                       this->Verts->GetInsertLocation(npts));
      break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->InsertNextCell(npts,pts);
      id = this->Cells->InsertNextCell(type, 
                                       this->Lines->GetInsertLocation(npts));
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->InsertNextCell(npts,pts);
      id = this->Cells->InsertNextCell(type, 
                                       this->Polys->GetInsertLocation(npts));
      break;

    case VTK_PIXEL: //need to rearrange vertices
      {
      static vtkIdType pixPts[4];
      pixPts[0] = pts[0];
      pixPts[1] = pts[1];
      pixPts[2] = pts[3];
      pixPts[3] = pts[2];
      this->Polys->InsertNextCell(npts,pixPts);
      id = this->Cells->InsertNextCell(VTK_QUAD, 
                                       this->Polys->GetInsertLocation(npts));
      break;
      }

    case VTK_TRIANGLE_STRIP:
      this->Strips->InsertNextCell(npts,pts);
      id = this->Cells->InsertNextCell(type, 
                                       this->Strips->GetInsertLocation(npts));
      break;

    default:
      id = -1;
      vtkErrorMacro(<<"Bad cell type! Can't insert!");
    }
  return id;
}

//----------------------------------------------------------------------------
// Insert a cell of type VTK_VERTEX, VTK_POLY_VERTEX, VTK_LINE, VTK_POLY_LINE,
// VTK_TRIANGLE, VTK_QUAD, VTK_POLYGON, or VTK_TRIANGLE_STRIP.  Make sure that
// the PolyData::Allocate() function has been called first or that vertex,
// line, polygon, and triangle strip arrays have been supplied.
// Note: will also insert VTK_PIXEL, but converts it to VTK_QUAD.
int vtkPolyData::InsertNextCell(int type, vtkIdList *pts)
{
  int id;
  int npts=pts->GetNumberOfIds();

  if ( !this->Cells ) 
    {
    this->Cells = vtkCellTypes::New();
    this->Cells->Allocate(5000,10000);
    }

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
      this->Verts->InsertNextCell(pts);
      id = this->Cells->InsertNextCell(type, this->Verts->GetInsertLocation(npts));
      break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->InsertNextCell(pts);
      id = this->Cells->InsertNextCell(type, this->Lines->GetInsertLocation(npts));
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->InsertNextCell(pts);
      id = this->Cells->InsertNextCell(type, this->Polys->GetInsertLocation(npts));
      break;

    case VTK_PIXEL: //need to rearrange vertices
      {
      static vtkIdType pixPts[4];
      pixPts[0] = pts->GetId(0);
      pixPts[1] = pts->GetId(1);
      pixPts[2] = pts->GetId(3);
      pixPts[3] = pts->GetId(2);
      this->Polys->InsertNextCell(4,pixPts);
      id = this->Cells->InsertNextCell(VTK_QUAD, this->Polys->GetInsertLocation(npts));
      break;
      }

    case VTK_TRIANGLE_STRIP:
      this->Strips->InsertNextCell(pts);
      id = this->Cells->InsertNextCell(type, this->Strips->GetInsertLocation(npts));
      break;

    default:
      id = -1;
      vtkErrorMacro(<<"Bad cell type! Can't insert!");
    }

  return id;
}

//----------------------------------------------------------------------------
// Recover extra allocated memory when creating data whose initial size
// is unknown. Examples include using the InsertNextCell() method, or
// when using the CellArray::EstimateSize() method to create vertices,
// lines, polygons, or triangle strips.
void vtkPolyData::Squeeze()
{
  if ( this->Verts != NULL )
    {
    this->Verts->Squeeze();
    }
  if ( this->Lines != NULL )
    {
    this->Lines->Squeeze();
    }
  if ( this->Polys != NULL )
    {
    this->Polys->Squeeze();
    }
  if ( this->Strips != NULL )
    {
    this->Strips->Squeeze();
    }

  vtkPointSet::Squeeze();
}

//----------------------------------------------------------------------------
// Begin inserting data all over again. Memory is not freed but otherwise
// objects are returned to their initial state.
void vtkPolyData::Reset()
{
  if ( this->Verts != NULL )
    {
    this->Verts->Reset();
    }
  if ( this->Lines != NULL )
    {
    this->Lines->Reset();
    }
  if ( this->Polys != NULL )
    {
    this->Polys->Reset();
    }
  if ( this->Strips != NULL )
    {
    this->Strips->Reset();
    }
}

//----------------------------------------------------------------------------
// Reverse the order of point ids defining the cell.
void vtkPolyData::ReverseCell(vtkIdType cellId)
{
  int loc, type;

  if ( this->Cells == NULL )
    {
    this->BuildCells();
    }
  loc = this->Cells->GetCellLocation(cellId);
  type = this->Cells->GetCellType(cellId);

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
     this->Verts->ReverseCell(loc);
     break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->ReverseCell(loc);
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->ReverseCell(loc);
      break;

    case VTK_TRIANGLE_STRIP:
      this->Strips->ReverseCell(loc);
      break;

    default:
      break;
    }
}

//----------------------------------------------------------------------------
// Add a point to the cell data structure (after cell pointers have been
// built). This method allocates memory for the links to the cells.  (To 
// use this method, make sure points are available and BuildLinks() has been invoked.)
int vtkPolyData::InsertNextLinkedPoint(int numLinks)
{
  return this->Links->InsertNextPoint(numLinks);
}

//----------------------------------------------------------------------------
// Add a point to the cell data structure (after cell pointers have been
// built). This method adds the point and then allocates memory for the
// links to the cells.  (To use this method, make sure points are available
// and BuildLinks() has been invoked.)
int vtkPolyData::InsertNextLinkedPoint(float x[3], int numLinks)
{
  this->Links->InsertNextPoint(numLinks);
  return this->Points->InsertNextPoint(x);
}

//----------------------------------------------------------------------------
// Add a new cell to the cell data structure (after cell pointers have been
// built). This method adds the cell and then updates the links from the points
// to the cells. (Memory is allocated as necessary.)
int vtkPolyData::InsertNextLinkedCell(int type, int npts, vtkIdType *pts)
{
  int i, id;

  id = this->InsertNextCell(type,npts,pts);

  for (i=0; i<npts; i++)
    {
    this->Links->ResizeCellList(pts[i],1);
    this->Links->AddCellReference(id,pts[i]);  
    }

  return id;
}

//----------------------------------------------------------------------------
// Remove a reference to a cell in a particular point's link list. You may also
// consider using RemoveCellReference() to remove the references from all the 
// cell's points to the cell. This operator does not reallocate memory; use the
// operator ResizeCellList() to do this if necessary.
void vtkPolyData::RemoveReferenceToCell(vtkIdType ptId, vtkIdType cellId)
{
  this->Links->RemoveCellReference(cellId, ptId);  
}

//----------------------------------------------------------------------------
// Add a reference to a cell in a particular point's link list. (You may also
// consider using AddCellReference() to add the references from all the 
// cell's points to the cell.) This operator does not realloc memory; use the
// operator ResizeCellList() to do this if necessary.
void vtkPolyData::AddReferenceToCell(vtkIdType ptId, vtkIdType cellId)
{
  this->Links->AddCellReference(cellId, ptId);  
}

//----------------------------------------------------------------------------
// Replace the points defining cell "cellId" with a new set of points. This
// operator is (typically) used when links from points to cells have not been 
// built (i.e., BuildLinks() has not been executed). Use the operator 
// ReplaceLinkedCell() to replace a cell when cell structure has been built.
void vtkPolyData::ReplaceCell(vtkIdType cellId, int npts, vtkIdType *pts)
{
  int loc, type;

  if ( this->Cells == NULL )
    {
    this->BuildCells();
    }
  loc = this->Cells->GetCellLocation(cellId);
  type = this->Cells->GetCellType(cellId);

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
     this->Verts->ReplaceCell(loc,npts,pts);
     break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->ReplaceCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->ReplaceCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE_STRIP:
      this->Strips->ReplaceCell(loc,npts,pts);
      break;

    default:
      break;
    }
}

//----------------------------------------------------------------------------
// Replace one cell with another in cell structure. This operator updates the
// connectivity list and the point's link list. It does not delete references
// to the old cell in the point's link list. Use the operator 
// RemoveCellReference() to delete all references from points to (old) cell.
// You may also want to consider using the operator ResizeCellList() if the 
// link list is changing size.
void vtkPolyData::ReplaceLinkedCell(vtkIdType cellId, int npts, vtkIdType *pts)
{
  int loc = this->Cells->GetCellLocation(cellId);
  int type = this->Cells->GetCellType(cellId);

  switch (type)
    {
    case VTK_VERTEX: case VTK_POLY_VERTEX:
     this->Verts->ReplaceCell(loc,npts,pts);
     break;

    case VTK_LINE: case VTK_POLY_LINE:
      this->Lines->ReplaceCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE: case VTK_QUAD: case VTK_POLYGON:
      this->Polys->ReplaceCell(loc,npts,pts);
      break;

    case VTK_TRIANGLE_STRIP:
      this->Strips->ReplaceCell(loc,npts,pts);
      break;

    default:
      npts = 0;
    }

  for (int i=0; i < npts; i++)
    {
    this->Links->InsertNextCellReference(pts[i],cellId);
    }
}

//----------------------------------------------------------------------------
// Get the neighbors at an edge. More efficient than the general 
// GetCellNeighbors(). Assumes links have been built (with BuildLinks()), 
// and looks specifically for edge neighbors.
void vtkPolyData::GetCellEdgeNeighbors(vtkIdType cellId, vtkIdType p1,
                                       vtkIdType p2, vtkIdList *cellIds)
{
  vtkIdType *cells;
  vtkIdType numCells;
  vtkIdType i,j;
  vtkIdType *pts, npts;
  
  cellIds->Reset();

  numCells = this->Links->GetNcells(p1);
  cells = this->Links->GetCells(p1);

  for (i=0; i < numCells; i++)
    {
    if ( cells[i] != cellId )
      {
      this->GetCellPoints(cells[i],npts,pts);
      for (j=0; j < npts; j++)
        {
        if ( pts[j] == p2 )
          {
          break;
          }
        }
      if ( j < npts )
        {
        cellIds->InsertNextId(cells[i]);
        }
      }
    }
}

//----------------------------------------------------------------------------
void vtkPolyData::GetCellNeighbors(vtkIdType cellId, vtkIdList *ptIds,
                                   vtkIdList *cellIds)
{
  vtkIdType i, j, numPts, cellNum;
  int allFound, oneFound;
  
  if ( ! this->Links )
    {
    this->BuildLinks();
    }  
  
  cellIds->Reset();
  
  // load list with candidate cells, remove current cell
  vtkIdType ptId = ptIds->GetId(0);
  int numPrime = this->Links->GetNcells(ptId);
  vtkIdType *primeCells = this->Links->GetCells(ptId);
  numPts = ptIds->GetNumberOfIds();
                        
  // for each potential cell
  for (cellNum = 0; cellNum < numPrime; cellNum++)
    {
    // ignore the original cell
    if (primeCells[cellNum] != cellId)
      {
      // are all the remaining points in the cell ?
      for (allFound=1, i=1; i < numPts && allFound; i++)
        {
        ptId = ptIds->GetId(i);
        int numCurrent = this->Links->GetNcells(ptId);
        vtkIdType *currentCells = this->Links->GetCells(ptId);
        oneFound = 0;
        for (j = 0; j < numCurrent; j++)
          {
          if (primeCells[cellNum] == currentCells[j])
            {
            oneFound = 1;
            break;
            }
          }
        if (!oneFound)
          {
          allFound = 0;
          }
        }
      if (allFound)
        {
        cellIds->InsertNextId(primeCells[cellNum]);
        }
      }
    }
}

int vtkPolyData::IsEdge(vtkIdType p1, vtkIdType p2)
{
  unsigned short int ncells;
  vtkIdType cellType;
  vtkIdType npts;
  vtkIdType i, j;
  vtkIdType *cells, *pts;
   
  this->GetPointCells(p1,ncells,cells);
  for (i=0; i<ncells; i++)
    {
    cellType = this->GetCellType(cells[i]);
    switch (cellType)
      {
      case VTK_EMPTY_CELL: case VTK_VERTEX: case VTK_POLY_VERTEX: case VTK_LINE: case VTK_POLY_LINE:
        break;
      case VTK_TRIANGLE:
        if ( this->IsPointUsedByCell(p2,cells[i]) )
          {
          return 1;
          }
        break;
      case VTK_QUAD:
        this->GetCellPoints(cells[i],npts,pts);
        for (j=0; j<npts-1; j++)
          {
          if (((pts[j]==p1)&&(pts[j+1]==p2))||((pts[j]==p2)&&(pts[j+1]==p1)))
            {
            return 1;
            }
          }
        if (((pts[0]==p1)&&(pts[npts-1]==p2))||((pts[0]==p2)&&(pts[npts-1]==p1)))
          {
          return 1;
          }
        break;
      case VTK_TRIANGLE_STRIP:
        this->GetCellPoints(cells[i],npts,pts);
        for (j=0; j<npts-2; j++)
          {
          if ((((pts[j]==p1)&&(pts[j+1]==p2))||((pts[j]==p2)&&(pts[j+1]==p1)))||
              (((pts[j]==p1)&&(pts[j+2]==p2))||((pts[j]==p2)&&(pts[j+2]==p1))))
            {
            return 1;
            }
          }
        if (((pts[npts-2]==p1)&&(pts[npts-1]==p2))||((pts[npts-2]==p2)&&(pts[npts-1]==p1)))
          {
          return 1;
          }
        break;
      default:
        this->GetCellPoints(cells[i],npts,pts);
        for (j=0; j<npts; j++)
          {
          if (p1==pts[j])
            {
            if ((pts[(j-1+npts)%npts]==p2)||(pts[(j+1)%npts]==p2))
              {
              return 1;
              }
            }
          }
      }
    }
  return 0;
}


//----------------------------------------------------------------------------

void vtkPolyData::SetUpdateExtent(int piece, int numPieces, int ghostLevel)
{
  this->UpdatePiece = piece;
  this->UpdateNumberOfPieces = numPieces;
  this->UpdateGhostLevel = ghostLevel;
  this->UpdateExtentInitialized = 1;
}

//----------------------------------------------------------------------------

void vtkPolyData::GetUpdateExtent(int &piece, int &numPieces, int &ghostLevel)
{
  piece = this->UpdatePiece;
  numPieces = this->UpdateNumberOfPieces;
  ghostLevel = this->UpdateGhostLevel;
}

//----------------------------------------------------------------------------

unsigned long vtkPolyData::GetActualMemorySize()
{
  unsigned long size=this->vtkPointSet::GetActualMemorySize();
  if ( this->Verts ) 
    {
    size += this->Verts->GetActualMemorySize();
    }
  if ( this->Lines ) 
    {
    size += this->Lines->GetActualMemorySize();
    }
  if ( this->Polys ) 
    {
    size += this->Polys->GetActualMemorySize();
    }
  if ( this->Strips ) 
    {
    size += this->Strips->GetActualMemorySize();
    }
  if ( this->Cells )
    {
    size += this->Cells->GetActualMemorySize();
    }
  if ( this->Links )
    {
    size += this->Links->GetActualMemorySize();
    }
  return size;
}

//----------------------------------------------------------------------------
void vtkPolyData::ShallowCopy(vtkDataObject *dataObject)
{
  vtkPolyData *polyData = vtkPolyData::SafeDownCast(dataObject);

  if ( polyData != NULL )
    {
    this->SetVerts(polyData->GetVerts());
    this->SetLines(polyData->GetLines());
    this->SetPolys(polyData->GetPolys());
    this->SetStrips(polyData->GetStrips());
    
    // I do not know if this is correct but.
    if (this->Cells)
      {
      this->Cells->UnRegister(this);
      }
    this->Cells = polyData->Cells;
    if (this->Cells)
      {
      this->Cells->Register(this);
      }

    if (this->Links)
      {
      this->Links->Delete();
      }
    this->Links = polyData->Links;
    if (this->Links)
      {
      this->Links->Register(this);
      }
    }

  // Do superclass
  this->vtkPointSet::ShallowCopy(dataObject);
}

//----------------------------------------------------------------------------
void vtkPolyData::DeepCopy(vtkDataObject *dataObject)
{
  // Do superclass
  // We have to do this BEFORE we call BuildLinks, else there are no points
  // to build the links on (the parent DeepCopy copies the points)
  this->vtkPointSet::DeepCopy(dataObject);

  vtkPolyData *polyData = vtkPolyData::SafeDownCast(dataObject);

  if ( polyData != NULL )
    {
    vtkCellArray *ca;
    ca = vtkCellArray::New();
    ca->DeepCopy(polyData->GetVerts());
    this->SetVerts(ca);
    ca->Delete();

    ca = vtkCellArray::New();
    ca->DeepCopy(polyData->GetLines());
    this->SetLines(ca);
    ca->Delete();

    ca = vtkCellArray::New();
    ca->DeepCopy(polyData->GetPolys());
    this->SetPolys(ca);
    ca->Delete();

    ca = vtkCellArray::New();
    ca->DeepCopy(polyData->GetStrips());
    this->SetStrips(ca);
    ca->Delete();

    if ( this->Cells )
      {
      this->Cells->UnRegister(this);
      this->Cells = NULL;
      }
    if (polyData->Cells)
      {
      this->BuildCells();
      }

    if ( this->Links )
      {
      this->Links->UnRegister(this);
      this->Links = NULL;
      }
    if (polyData->Links)
      {
      this->BuildLinks();
      }
    }
}

void vtkPolyData::Crop()
{
}

void vtkPolyData::RemoveGhostCells(int level)
{
  vtkCellData *newCellData;
  vtkCellArray *newVerts;
  vtkCellArray *newLines;
  vtkCellArray *newPolys;
  vtkCellArray *newStrips;
  vtkIdType inCellId, outCellId;
  vtkIdType npts=0;
  vtkIdType *pts=0;

  // Get a pointer to the cell ghost level array.
  vtkDataArray* temp = this->CellData->GetArray("vtkGhostLevels");
  if (temp == NULL)
    {
    vtkDebugMacro("Could not find cell ghost level array.");
    return;
    }
  if ( (temp->GetDataType() != VTK_UNSIGNED_CHAR)
       || (temp->GetNumberOfComponents() != 1)
       || (temp->GetNumberOfTuples() < this->GetNumberOfCells()))
    {
    vtkErrorMacro("Poorly formed ghost level array.");
    return;
    }
  unsigned char* cellGhostLevels =((vtkUnsignedCharArray*)temp)->GetPointer(0);

  // We may be able to get away wil just creating a CellData object.
  newCellData = vtkCellData::New();
  newCellData->CopyAllocate(this->CellData, this->GetNumberOfCells());

  inCellId = outCellId = 0;
  if (this->Verts)
    {
    newVerts = vtkCellArray::New();
    newVerts->Allocate(this->Verts->GetSize());
    for (this->Verts->InitTraversal(); this->Verts->GetNextCell(npts, pts); )
      {
      if (int(cellGhostLevels[inCellId]) < level)
        { // Keep the cell.
        newVerts->InsertNextCell(npts, pts);
        newCellData->CopyData(this->CellData, inCellId, outCellId);
        ++outCellId;
        } // Keep this cell.
      ++inCellId;
      } // for all cells
    this->SetVerts(newVerts);
    newVerts->Delete();
    newVerts = NULL;
    }

  if (this->Lines)
    {
    newLines = vtkCellArray::New();
    newLines->Allocate(this->Lines->GetSize());
    for (this->Lines->InitTraversal(); this->Lines->GetNextCell(npts, pts); )
      {
      if (int(cellGhostLevels[inCellId]) < level)
        { // Keep the cell.
        newLines->InsertNextCell(npts, pts);
        newCellData->CopyData(this->CellData, inCellId, outCellId);
        ++outCellId;
        } // Keep this cell.
      ++inCellId;
      } // for all cells
    this->SetLines(newLines);
    newLines->Delete();
    newLines = NULL;
    }

  if (this->Polys)
    {
    newPolys = vtkCellArray::New();
    newPolys->Allocate(this->Polys->GetSize());
    for (this->Polys->InitTraversal(); this->Polys->GetNextCell(npts, pts); )
      {
      if (int(cellGhostLevels[inCellId]) < level)
        { // Keep the cell.
        newPolys->InsertNextCell(npts, pts);
        newCellData->CopyData(this->CellData, inCellId, outCellId);
        ++outCellId;
        } // Keep this cell.
      ++inCellId;
      } // for all cells
   this->SetPolys(newPolys);
   newPolys->Delete();
   newPolys = NULL;
   }

  if (this->Strips)
    {
    newStrips = vtkCellArray::New();
    newStrips->Allocate(this->Strips->GetSize());
    for (this->Strips->InitTraversal(); this->Strips->GetNextCell(npts, pts); )
      {
      if (int(cellGhostLevels[inCellId]) < level)
        { // Keep the cell.
        newStrips->InsertNextCell(npts, pts);
        newCellData->CopyData(this->CellData, inCellId, outCellId);
        ++outCellId;
        } // Keep this cell.
      ++inCellId;
      } // for all cells
    this->SetStrips(newStrips);
    newStrips->Delete();
    newStrips = NULL;
    }

  // Save the results.
  this->CellData->ShallowCopy(newCellData);
  newCellData->Delete();

  // If there are no more ghost levels, then remove all arrays.
  if (level <= 1)
    {
    this->CellData->RemoveArray("vtkGhostLevels");
    this->PointData->RemoveArray("vtkGhostLevels");
    }

  this->Squeeze();
}




void vtkPolyData::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os,indent);

  os << indent << "Number Of Vertices: " << this->GetNumberOfVerts() << "\n";
  os << indent << "Number Of Lines: " << this->GetNumberOfLines() << "\n";
  os << indent << "Number Of Polygons: " << this->GetNumberOfPolys() << "\n";
  os << indent << "Number Of Triangle Strips: " << this->GetNumberOfStrips() << "\n";

  os << indent << "Number Of Pieces: " << this->NumberOfPieces << endl;
  os << indent << "Piece: " << this->Piece << endl;
  os << indent << "Ghost Level: " << this->GhostLevel << endl;
  
  os << indent << "UpdateExtent: " << this->UpdateExtent[0] << ", "
     << this->UpdateExtent[1] << ", " << this->UpdateExtent[2] << ", "
     << this->UpdateExtent[3] << ", " << this->UpdateExtent[4] << ", "
     << this->UpdateExtent[5] << endl;
}
