Method RequestData

Filters/GeometryPreview/vtkPointSetToOctreeImageFilter.cxx:238–415

------------------------------------------------------------------------------

//------------------------------------------------------------------------------
int vtkPointSetToOctreeImageFilter::RequestData(
  vtkInformation*, vtkInformationVector** inputVector, vtkInformationVector* outputVector)
{
  // get the input
  vtkInformation* inInfo = inputVector[0]->GetInformationObject(0);
  vtkPointSet* input = vtkPointSet::GetData(inInfo);

  // get the output
  vtkInformation* outInfo = outputVector->GetInformationObject(0);
  vtkPartitionedDataSet* outputPDS = vtkPartitionedDataSet::GetData(outInfo);

  if (!input || input->GetNumberOfPoints() == 0)
  {
    vtkErrorMacro("No input or empty input.");
    return 0;
  }

  if (this->NumberOfPointsPerCell > input->GetNumberOfPoints())
  {
    vtkErrorMacro("NumberOfPointsPerCell must be less than or equal to the number of points.");
    return 0;
  }

  // get input points information
  double pointSetBounds[6];
  input->GetBounds(pointSetBounds);

  // compute output image information as it's done in vtkStaticPointLocator when Automatic is on.
  double imageBounds[6];
  int nDivs[3];
  vtkIdType numBuckets = static_cast<vtkIdType>(static_cast<double>(input->GetNumberOfPoints()) /
    static_cast<double>(this->NumberOfPointsPerCell));
  vtkBoundingBox bbox(pointSetBounds);
  bbox.ComputeDivisions(numBuckets, imageBounds, nDivs);
  const double origin[3] = { imageBounds[0], imageBounds[2], imageBounds[4] };
  const double spacing[3] = { (imageBounds[1] - imageBounds[0]) / static_cast<double>(nDivs[0]),
    (imageBounds[3] - imageBounds[2]) / static_cast<double>(nDivs[1]),
    (imageBounds[5] - imageBounds[4]) / static_cast<double>(nDivs[2]) };
  const int dimensions[3] = { 1 + nDivs[0], 1 + nDivs[1], 1 + nDivs[2] };
  const vtkIdType numberOfCells = nDivs[0] * nDivs[1] * nDivs[2];

  // create output image octree array
  vtkNew<vtkUnsignedCharArray> octree;
  octree->SetName("octree");
  octree->SetNumberOfValues(numberOfCells);
  vtkSMPTools::Fill(octree->GetPointer(0), octree->GetPointer(0) + numberOfCells, 0);

  // create output image field array
  vtkSmartPointer<vtkFloatArray> outField = nullptr;
  vtkDataArray* inField = nullptr;
  std::vector<FieldFunctions> functions;
  if (this->ProcessInputPointArray)
  {
    inField = this->GetInputArrayToProcess(0, inputVector);
    if (!inField)
    {
      vtkErrorMacro("Array to process is null.");
      return 0;