Filters/Core/vtkConnectivityFilter.cxx

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

  Program:   Visualization Toolkit
  Module:    vtkConnectivityFilter.cxx

  Copyright (c) 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 "vtkConnectivityFilter.h"

#include "vtkCell.h"
#include "vtkCellData.h"
#include "vtkDataSet.h"
#include "vtkDemandDrivenPipeline.h"
#include "vtkFloatArray.h"
#include "vtkIdList.h"
#include "vtkIdTypeArray.h"
#include "vtkInformation.h"
#include "vtkInformationVector.h"
#include "vtkMath.h"
#include "vtkObjectFactory.h"
#include "vtkPointData.h"
#include "vtkPoints.h"
#include "vtkPolyData.h"
#include "vtkUnstructuredGrid.h"

#include <map>

vtkObjectFactoryNewMacro(vtkConnectivityFilter);

// Construct with default extraction mode to extract largest regions.
vtkConnectivityFilter::vtkConnectivityFilter()
{
  this->RegionSizes = vtkIdTypeArray::New();
  this->ExtractionMode = VTK_EXTRACT_LARGEST_REGION;
  this->ColorRegions = 0;
  this->RegionIdAssignmentMode = UNSPECIFIED;

  this->ScalarConnectivity = 0;
  this->ScalarRange[0] = 0.0;
  this->ScalarRange[1] = 1.0;

  this->ClosestPoint[0] = this->ClosestPoint[1] = this->ClosestPoint[2] = 0.0;

  this->CellScalars = vtkFloatArray::New();
  this->CellScalars->Allocate(8);

  this->NeighborCellPointIds = vtkIdList::New();
  this->NeighborCellPointIds->Allocate(8);

  this->Seeds = vtkIdList::New();
  this->SpecifiedRegionIds = vtkIdList::New();

  this->NewScalars = nullptr;
  this->NewCellScalars = nullptr;

  this->OutputPointsPrecision = vtkAlgorithm::DEFAULT_PRECISION;
}

vtkConnectivityFilter::~vtkConnectivityFilter()
{
  this->RegionSizes->Delete();
  this->CellScalars->Delete();
  this->NeighborCellPointIds->Delete();
  this->Seeds->Delete();
  this->SpecifiedRegionIds->Delete();
}

int vtkConnectivityFilter::RequestDataObject(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
  if (!inInfo)
  {
    return 0;
  }

  vtkDataObject* input = inInfo->Get(vtkDataObject::DATA_OBJECT());
  if (input)
  {
    // for each output
    for (int i = 0; i < this->GetNumberOfOutputPorts(); ++i)
    {
      vtkInformation* info = outputVector->GetInformationObject(i);
      vtkDataObject* output = info->Get(vtkDataObject::DATA_OBJECT());

      if (!output || !output->IsA(input->GetClassName()))
      {
        vtkDataObject* newOutput = nullptr;
        if (input->IsA("vtkPolyData"))
        {
          newOutput = input->NewInstance();
        }
        else
        {
          newOutput = vtkUnstructuredGrid::New();
        }

        info->Set(vtkDataObject::DATA_OBJECT(), newOutput);
        newOutput->Delete();
        this->GetOutputPortInformation(0)->Set(
          vtkDataObject::DATA_EXTENT_TYPE(), newOutput->GetExtentType());
      }
    }
    return 1;
  }

  return 0;
}

int vtkConnectivityFilter::RequestData(vtkInformation* vtkNotUsed(request),
  vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  // get the info objects
  vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
  vtkInformation* outInfo = outputVector->GetInformationObject(0);

  // get the input and output
  vtkDataSet* input = vtkDataSet::SafeDownCast(inInfo->Get(vtkDataObject::DATA_OBJECT()));
  vtkPointSet* output = vtkPointSet::SafeDownCast(outInfo->Get(vtkDataObject::DATA_OBJECT()));

  vtkPolyData* pdOutput = vtkPolyData::SafeDownCast(output);
  vtkUnstructuredGrid* ugOutput = vtkUnstructuredGrid::SafeDownCast(output);

  vtkIdType numPts, numCells, cellId, i, j, pt;
  vtkPoints* newPts;
  vtkIdType id;
  vtkIdType maxCellsInRegion;
  vtkIdType largestRegionId = 0;
  vtkPointData *pd = input->GetPointData(), *outputPD = output->GetPointData();
  vtkCellData *cd = input->GetCellData(), *outputCD = output->GetCellData();

  vtkDebugMacro(<< "Executing connectivity filter.");

  //  Check input/allocate storage
  //
  numCells = input->GetNumberOfCells();
  if ((numPts = input->GetNumberOfPoints()) < 1 || numCells < 1)
  {
    vtkDebugMacro(<< "No data to connect!");
    return 1;
  }

  if (pdOutput)
  {
    pdOutput->AllocateExact(numCells, 3);
  }
  if (ugOutput)
  {
    ugOutput->Allocate(numCells, numCells);
  }

  // See whether to consider scalar connectivity
  //
  this->InScalars = input->GetPointData()->GetScalars();
  if (!this->ScalarConnectivity)
  {
    this->InScalars = nullptr;
  }
  else
  {
    if (this->ScalarRange[1] < this->ScalarRange[0])
    {
      this->ScalarRange[1] = this->ScalarRange[0];
    }
  }

  // Initialize.  Keep track of points and cells visited.
  //
  this->RegionSizes->Reset();
  this->Visited = new vtkIdType[numCells];
  for (i = 0; i < numCells; i++)
  {
    this->Visited[i] = -1;
  }
  this->PointMap = new vtkIdType[numPts];
  for (i = 0; i < numPts; i++)
  {
    this->PointMap[i] = -1;
  }

  this->NewScalars = vtkIdTypeArray::New();
  this->NewScalars->SetName("RegionId");
  this->NewScalars->SetNumberOfTuples(numPts);

  this->NewCellScalars = vtkIdTypeArray::New();
  this->NewCellScalars->SetName("RegionId");
  this->NewCellScalars->SetNumberOfTuples(numCells);

  newPts = vtkPoints::New();

  // Set the desired precision for the points in the output.
  if (this->OutputPointsPrecision == vtkAlgorithm::DEFAULT_PRECISION)
  {
    vtkPointSet* inputPointSet = vtkPointSet::SafeDownCast(input);
    if (inputPointSet)
    {
      newPts->SetDataType(inputPointSet->GetPoints()->GetDataType());
    }
    else
    {
      newPts->SetDataType(VTK_FLOAT);
    }
  }
  else if (this->OutputPointsPrecision == vtkAlgorithm::SINGLE_PRECISION)
  {
    newPts->SetDataType(VTK_FLOAT);
  }
  else if (this->OutputPointsPrecision == vtkAlgorithm::DOUBLE_PRECISION)
  {
    newPts->SetDataType(VTK_DOUBLE);
  }

  newPts->Allocate(numPts);

  // Traverse all cells marking those visited.  Each new search
  // starts a new connected region. Connected region grows
  // using a connected wave propagation.
  //
  this->Wave = vtkIdList::New();
  this->Wave->Allocate(numPts / 4 + 1, numPts);
  this->Wave2 = vtkIdList::New();
  this->Wave2->Allocate(numPts / 4 + 1, numPts);

  this->PointNumber = 0;
  this->RegionNumber = 0;
  maxCellsInRegion = 0;

  this->CellIds = vtkIdList::New();
  this->CellIds->Allocate(8, VTK_CELL_SIZE);
  this->PointIds = vtkIdList::New();
  this->PointIds->Allocate(8, VTK_CELL_SIZE);

  if (this->ExtractionMode != VTK_EXTRACT_POINT_SEEDED_REGIONS &&
    this->ExtractionMode != VTK_EXTRACT_CELL_SEEDED_REGIONS &&
    this->ExtractionMode != VTK_EXTRACT_CLOSEST_POINT_REGION)
  { // visit all cells marking with region number
    for (cellId = 0; cellId < numCells; cellId++)
    {
      if (cellId && !(cellId % 5000))
      {
        this->UpdateProgress(0.1 + 0.8 * cellId / numCells);
      }

      if (this->Visited[cellId] < 0)
      {
        this->NumCellsInRegion = 0;
        this->Wave->InsertNextId(cellId);
        this->TraverseAndMark(input);

        if (this->NumCellsInRegion > maxCellsInRegion)
        {
          maxCellsInRegion = this->NumCellsInRegion;
          largestRegionId = this->RegionNumber;
        }

        this->RegionSizes->InsertValue(this->RegionNumber++, this->NumCellsInRegion);
        this->Wave->Reset();
        this->Wave2->Reset();
      }
    }
  }
  else // regions have been seeded, everything considered in same region
  {
    this->NumCellsInRegion = 0;

    if (this->ExtractionMode == VTK_EXTRACT_POINT_SEEDED_REGIONS)
    {
      for (i = 0; i < this->Seeds->GetNumberOfIds(); i++)
      {
        pt = this->Seeds->GetId(i);
        if (pt >= 0)
        {
          input->GetPointCells(pt, this->CellIds);
          for (j = 0; j < this->CellIds->GetNumberOfIds(); j++)
          {
            this->Wave->InsertNextId(this->CellIds->GetId(j));
          }
        }
      }
    }
    else if (this->ExtractionMode == VTK_EXTRACT_CELL_SEEDED_REGIONS)
    {
      for (i = 0; i < this->Seeds->GetNumberOfIds(); i++)
      {
        cellId = this->Seeds->GetId(i);
        if (cellId >= 0)
        {
          this->Wave->InsertNextId(cellId);
        }
      }
    }
    else if (this->ExtractionMode == VTK_EXTRACT_CLOSEST_POINT_REGION)
    { // loop over points, find closest one
      double minDist2, dist2, x[3];
      vtkIdType minId = 0;
      for (minDist2 = VTK_DOUBLE_MAX, i = 0; i < numPts; i++)
      {
        input->GetPoint(i, x);
        dist2 = vtkMath::Distance2BetweenPoints(x, this->ClosestPoint);
        if (dist2 < minDist2)
        {
          minId = i;
          minDist2 = dist2;
        }
      }
      input->GetPointCells(minId, this->CellIds);
      for (j = 0; j < this->CellIds->GetNumberOfIds(); j++)
      {
        this->Wave->InsertNextId(this->CellIds->GetId(j));
      }
    }
    this->UpdateProgress(0.5);

    // mark all seeded regions
    this->TraverseAndMark(input);
    this->RegionSizes->InsertValue(this->RegionNumber, this->NumCellsInRegion);
    this->UpdateProgress(0.9);
  }

  vtkDebugMacro(<< "Extracted " << this->RegionNumber << " region(s)");
  this->Wave->Delete();
  this->Wave2->Delete();

  // Now that points and cells have been marked, traverse these lists pulling
  // everything that has been visited.
  //
  // Pass through point data that has been visited
  outputPD->CopyAllocate(pd);
  outputCD->CopyAllocate(cd);

  for (i = 0; i < numPts; i++)
  {
    if (this->PointMap[i] > -1)
    {
      newPts->InsertPoint(this->PointMap[i], input->GetPoint(i));
      outputPD->CopyData(pd, i, this->PointMap[i]);
    }
  }

  // if coloring regions; send down new scalar data
  if (this->ColorRegions)
  {
    this->OrderRegionIds(this->NewScalars, this->NewCellScalars);

    int idx = outputPD->AddArray(this->NewScalars);
    outputPD->SetActiveAttribute(idx, vtkDataSetAttributes::SCALARS);
    idx = outputCD->AddArray(this->NewCellScalars);
    outputCD->SetActiveAttribute(idx, vtkDataSetAttributes::SCALARS);
  }
  this->NewScalars->Delete();
  this->NewCellScalars->Delete();

  output->SetPoints(newPts);
  newPts->Delete();

  // Create output cells
  //
  if (this->ExtractionMode == VTK_EXTRACT_POINT_SEEDED_REGIONS ||
    this->ExtractionMode == VTK_EXTRACT_CELL_SEEDED_REGIONS ||
    this->ExtractionMode == VTK_EXTRACT_CLOSEST_POINT_REGION ||
    this->ExtractionMode == VTK_EXTRACT_ALL_REGIONS)
  { // extract any cell that's been visited
    for (cellId = 0; cellId < numCells; cellId++)
    {
      if (this->Visited[cellId] >= 0)
      {
        // special handling for polyhedron cells
        if (vtkUnstructuredGrid::SafeDownCast(input) &&
          input->GetCellType(cellId) == VTK_POLYHEDRON)
        {
          vtkUnstructuredGrid::SafeDownCast(input)->GetFaceStream(cellId, this->PointIds);
          vtkUnstructuredGrid::ConvertFaceStreamPointIds(this->PointIds, this->PointMap);
        }
        else
        {
          input->GetCellPoints(cellId, this->PointIds);
          for (i = 0; i < this->PointIds->GetNumberOfIds(); i++)
          {
            id = this->PointMap[this->PointIds->GetId(i)];
            this->PointIds->InsertId(i, id);
          }
        }
        vtkIdType newCellId = -1;
        if (pdOutput)
        {
          newCellId = pdOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
        }
        else if (ugOutput)
        {
          newCellId = ugOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
        }
        if (newCellId >= 0)
        {
          outputCD->CopyData(cd, cellId, newCellId);
        }
      }
    }
  }
  else if (this->ExtractionMode == VTK_EXTRACT_SPECIFIED_REGIONS)
  {
    for (cellId = 0; cellId < numCells; cellId++)
    {
      int inReg, regionId;
      if ((regionId = this->Visited[cellId]) >= 0)
      {
        for (inReg = 0, i = 0; i < this->SpecifiedRegionIds->GetNumberOfIds(); i++)
        {
          if (regionId == this->SpecifiedRegionIds->GetId(i))
          {
            inReg = 1;
            break;
          }
        }
        if (inReg)
        {
          // special handling for polyhedron cells
          if (vtkUnstructuredGrid::SafeDownCast(input) &&
            input->GetCellType(cellId) == VTK_POLYHEDRON)
          {
            vtkUnstructuredGrid::SafeDownCast(input)->GetFaceStream(cellId, this->PointIds);
            vtkUnstructuredGrid::ConvertFaceStreamPointIds(this->PointIds, this->PointMap);
          }
          else
          {
            input->GetCellPoints(cellId, this->PointIds);
            for (i = 0; i < this->PointIds->GetNumberOfIds(); i++)
            {
              id = this->PointMap[this->PointIds->GetId(i)];
              this->PointIds->InsertId(i, id);
            }
          }
          vtkIdType newCellId = -1;
          if (pdOutput)
          {
            newCellId = pdOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
          }
          else if (ugOutput)
          {
            newCellId = ugOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
          }
          if (newCellId >= 0)
          {
            outputCD->CopyData(cd, cellId, newCellId);
          }
        }
      }
    }
  }
  else // extract largest region
  {
    for (cellId = 0; cellId < numCells; cellId++)
    {
      if (this->Visited[cellId] == largestRegionId)
      {
        // special handling for polyhedron cells
        if (vtkUnstructuredGrid::SafeDownCast(input) &&
          input->GetCellType(cellId) == VTK_POLYHEDRON)
        {
          vtkUnstructuredGrid::SafeDownCast(input)->GetFaceStream(cellId, this->PointIds);
          vtkUnstructuredGrid::ConvertFaceStreamPointIds(this->PointIds, this->PointMap);
        }
        else
        {
          input->GetCellPoints(cellId, this->PointIds);
          for (i = 0; i < this->PointIds->GetNumberOfIds(); i++)
          {
            id = this->PointMap[this->PointIds->GetId(i)];
            this->PointIds->InsertId(i, id);
          }
        }
        vtkIdType newCellId = -1;
        if (pdOutput)
        {
          newCellId = pdOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
        }
        else if (ugOutput)
        {
          newCellId = ugOutput->InsertNextCell(input->GetCellType(cellId), this->PointIds);
        }
        if (newCellId >= 0)
        {
          outputCD->CopyData(cd, cellId, newCellId);
        }
      }
    }
  }

  delete[] this->Visited;
  delete[] this->PointMap;
  this->PointIds->Delete();
  this->CellIds->Delete();
  output->Squeeze();
  vtkDataArray* outScalars = nullptr;
  if (this->ColorRegions && (outScalars = output->GetPointData()->GetScalars()))
  {
    outScalars->Resize(output->GetNumberOfPoints());
  }

  int num = this->GetNumberOfExtractedRegions();
  int count = 0;

  for (int ii = 0; ii < num; ii++)
  {
    count += this->RegionSizes->GetValue(ii);
  }
  vtkDebugMacro(<< "Total # of cells accounted for: " << count);
  vtkDebugMacro(<< "Extracted " << output->GetNumberOfCells() << " cells");

  return 1;
}

// Mark current cell as visited and assign region number.  Note:
// traversal occurs across shared vertices.
//
void vtkConnectivityFilter::TraverseAndMark(vtkDataSet* input)
{
  vtkIdType i, j, k, cellId, numIds, ptId, numPts, numCells;
  vtkIdList* tmpWave;

  while ((numIds = this->Wave->GetNumberOfIds()) > 0)
  {
    for (i = 0; i < numIds; i++)
    {
      cellId = this->Wave->GetId(i);
      if (this->Visited[cellId] < 0)
      {
        this->NewCellScalars->SetValue(cellId, this->RegionNumber);
        this->Visited[cellId] = this->RegionNumber;
        this->NumCellsInRegion++;
        input->GetCellPoints(cellId, this->PointIds);

        numPts = this->PointIds->GetNumberOfIds();
        for (j = 0; j < numPts; j++)
        {
          if (this->PointMap[ptId = this->PointIds->GetId(j)] < 0)
          {
            this->PointMap[ptId] = this->PointNumber++;
            this->NewScalars->SetValue(this->PointMap[ptId], this->RegionNumber);
          }

          input->GetPointCells(ptId, this->CellIds);

          // check connectivity criterion (geometric + scalar)
          numCells = this->CellIds->GetNumberOfIds();
          for (k = 0; k < numCells; k++)
          {
            cellId = this->CellIds->GetId(k);
            if (this->InScalars)
            {
              int numScalars, ii;
              double s, range[2];

              input->GetCellPoints(cellId, this->NeighborCellPointIds);
              numScalars = this->NeighborCellPointIds->GetNumberOfIds();
              this->CellScalars->SetNumberOfComponents(this->InScalars->GetNumberOfComponents());
              this->CellScalars->SetNumberOfTuples(numScalars);
              this->InScalars->GetTuples(this->NeighborCellPointIds, this->CellScalars);
              range[0] = VTK_DOUBLE_MAX;
              range[1] = -VTK_DOUBLE_MAX;
              for (ii = 0; ii < numScalars; ii++)
              {
                s = this->CellScalars->GetComponent(ii, 0);
                if (s < range[0])
                {
                  range[0] = s;
                }
                if (s > range[1])
                {
                  range[1] = s;
                }
              }
              if (range[1] >= this->ScalarRange[0] && range[0] <= this->ScalarRange[1])
              {
                this->Wave2->InsertNextId(cellId);
              }
            }
            else
            {
              this->Wave2->InsertNextId(cellId);
            }
          } // for all cells using this point
        }   // for all points of this cell
      }     // if cell not yet visited
    }       // for all cells in this wave

    tmpWave = this->Wave;
    this->Wave = this->Wave2;
    this->Wave2 = tmpWave;
    tmpWave->Reset();
  } // while wave is not empty
}

void vtkConnectivityFilter::OrderRegionIds(
  vtkIdTypeArray* pointRegionIds, vtkIdTypeArray* cellRegionIds)
{
  if (this->ColorRegions)
  {
    if (this->RegionIdAssignmentMode == CELL_COUNT_DESCENDING ||
      this->RegionIdAssignmentMode == CELL_COUNT_ASCENDING)
    {
      // Use a multimap to handle cases where more than one region has the same number of cells.
      std::multimap<vtkIdType, vtkIdType> cellCountToRegionId;
      typedef std::multimap<vtkIdType, vtkIdType>::value_type ValueType;
      vtkIdType numRegions = this->RegionSizes->GetNumberOfTuples();
      for (vtkIdType regionId = 0; regionId < numRegions; ++regionId)
      {
        ValueType value(this->RegionSizes->GetValue(regionId), regionId);
        cellCountToRegionId.insert(value);
      }

      // Now reverse iterate through the sorted multimap to process the RegionIds
      // from largest to smallest and create a map from the old RegionId to the new
      // RegionId
      std::map<vtkIdType, vtkIdType> oldToNew;
      vtkIdType counter = 0;
      if (this->RegionIdAssignmentMode == CELL_COUNT_ASCENDING)
      {
        for (auto iter = cellCountToRegionId.begin(); iter != cellCountToRegionId.end(); ++iter)
        {
          auto regionCount = iter->first;
          auto regionId = iter->second;

          // Re-order the region sizes based on the sorting
          this->RegionSizes->SetValue(counter, regionCount);

          // Create map from old to new RegionId
          oldToNew[regionId] = counter++;
        }
      }
      else // CELL_COUNT_DESCENDING
      {
        for (auto iter = cellCountToRegionId.rbegin(); iter != cellCountToRegionId.rend(); ++iter)
        {
          auto regionCount = iter->first;
          auto regionId = iter->second;

          // Re-order the region sizes based on the sorting
          this->RegionSizes->SetValue(counter, regionCount);

          // Create map from old to new RegionId
          oldToNew[regionId] = counter++;
        }
      }

      vtkIdType numPts = pointRegionIds->GetNumberOfTuples();
      for (vtkIdType i = 0; i < numPts; ++i)
      {
        vtkIdType oldValue = pointRegionIds->GetValue(i);
        pointRegionIds->SetValue(i, oldToNew[oldValue]);
      }

      vtkIdType numCells = cellRegionIds->GetNumberOfTuples();
      for (vtkIdType i = 0; i < numCells; ++i)
      {
        vtkIdType oldValue = cellRegionIds->GetValue(i);
        cellRegionIds->SetValue(i, oldToNew[oldValue]);
      }
    }
    // else UNSPECIFIED mode
  }
}

// Obtain the number of connected regions.
int vtkConnectivityFilter::GetNumberOfExtractedRegions()
{
  return this->RegionSizes->GetMaxId() + 1;
}

vtkTypeBool vtkConnectivityFilter::ProcessRequest(
  vtkInformation* request, vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  if (request->Has(vtkDemandDrivenPipeline::REQUEST_DATA_OBJECT()))
  {
    return this->RequestDataObject(request, inputVector, outputVector);
  }

  return this->Superclass::ProcessRequest(request, inputVector, outputVector);
}

// Initialize list of point ids/cell ids used to seed regions.
void vtkConnectivityFilter::InitializeSeedList()
{
  this->Modified();
  this->Seeds->Reset();
}

// Add a seed id (point or cell id). Note: ids are 0-offset.
void vtkConnectivityFilter::AddSeed(vtkIdType id)
{
  this->Modified();
  this->Seeds->InsertNextId(id);
}

// Delete a seed id (point or cell id). Note: ids are 0-offset.
void vtkConnectivityFilter::DeleteSeed(vtkIdType id)
{
  this->Modified();
  this->Seeds->DeleteId(id);
}

// Initialize list of region ids to extract.
void vtkConnectivityFilter::InitializeSpecifiedRegionList()
{
  this->Modified();
  this->SpecifiedRegionIds->Reset();
}

// Add a region id to extract. Note: ids are 0-offset.
void vtkConnectivityFilter::AddSpecifiedRegion(int id)
{
  this->Modified();
  this->SpecifiedRegionIds->InsertNextId(id);
}

// Delete a region id to extract. Note: ids are 0-offset.
void vtkConnectivityFilter::DeleteSpecifiedRegion(int id)
{
  this->Modified();
  this->SpecifiedRegionIds->DeleteId(id);
}

int vtkConnectivityFilter::FillInputPortInformation(int, vtkInformation* info)
{
  info->Set(vtkAlgorithm::INPUT_REQUIRED_DATA_TYPE(), "vtkDataSet");
  return 1;
}

int vtkConnectivityFilter::FillOutputPortInformation(int vtkNotUsed(port), vtkInformation* info)
{
  info->Set(vtkDataObject::DATA_TYPE_NAME(), "vtkDataSet");
  return 1;
}

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

  os << indent << "Extraction Mode: ";
  os << this->GetExtractionModeAsString() << "\n";

  os << indent << "Closest Point: (" << this->ClosestPoint[0] << ", " << this->ClosestPoint[1]
     << ", " << this->ClosestPoint[2] << ")\n";

  os << indent << "Color Regions: " << (this->ColorRegions ? "On\n" : "Off\n");

  os << indent << "Scalar Connectivity: " << (this->ScalarConnectivity ? "On\n" : "Off\n");

  double* range = this->GetScalarRange();
  os << indent << "Scalar Range: (" << range[0] << ", " << range[1] << ")\n";
  os << indent << "Output Points Precision: " << this->OutputPointsPrecision << "\n";
}