Method ImageContour

Filters/General/vtkMarchingContourFilter.cxx:224–282

}

void vtkMarchingContourFilter::ImageContour(int dim, vtkDataSet* input, vtkPolyData* output)
{
  vtkIdType numContours = this->ContourValues->GetNumberOfContours();
  double* values = this->ContourValues->GetValues();
  vtkPolyData* contourOutput;

  vtkNew<vtkTrivialProducer> producer;
  producer->SetOutput(input);
  producer->SetContainerAlgorithm(this);
  // Explicitly update the update extent in the trivial producer to prevent
  // an error when downstream algorithms request a different extent.
  producer->UpdateWholeExtent();

  if (dim == 2) // marching squares
  {
    vtkMarchingSquares* msquares;
    int i;

    msquares = vtkMarchingSquares::New();
    msquares->SetInputConnection(producer->GetOutputPort());
    msquares->SetDebug(this->Debug);
    msquares->SetNumberOfContours(numContours);
    for (i = 0; i < numContours; i++)
    {
      msquares->SetValue(i, values[i]);
    }

    contourOutput = msquares->GetOutput();
    msquares->SetContainerAlgorithm(this);
    msquares->Update();
    output->ShallowCopy(contourOutput);
    msquares->Delete();
  }

  else // image marching cubes
  {
    vtkImageMarchingCubes* mcubes;
    int i;

    mcubes = vtkImageMarchingCubes::New();

    mcubes->SetInputConnection(producer->GetOutputPort());
    mcubes->SetComputeNormals(this->ComputeNormals);
    mcubes->SetComputeGradients(this->ComputeGradients);
    mcubes->SetComputeScalars(this->ComputeScalars);
    mcubes->SetDebug(this->Debug);
    mcubes->SetNumberOfContours(numContours);
    for (i = 0; i < numContours; i++)
    {
      mcubes->SetValue(i, values[i]);
    }

    contourOutput = mcubes->GetOutput();
    mcubes->SetContainerAlgorithm(this);
    mcubes->Update();
    output->ShallowCopy(contourOutput);
    mcubes->Delete();
  }