Method IntersectsCell

Common/DataModel/vtkKdNode.cxx:714–886

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int vtkKdNode::IntersectsCell(vtkCell* cell, int useDataBounds, int cellRegion, double* bounds)
{
  vtkIdType i;

  if ((useDataBounds == 0) && (cellRegion >= 0))
  {
    if ((cellRegion >= this->MinID) && (cellRegion <= this->MaxID))
    {
      return 1; // the cell centroid is contained in this spatial region
    }
  }

  double* cellBounds = nullptr;
  int deleteCellBounds = (bounds == nullptr);

  if (deleteCellBounds)
  {
    cellBounds = new double[6];

    vtkPoints* pts = cell->GetPoints();
    pts->Modified(); // VTK bug - so bounds will be re-calculated
    pts->GetBounds(cellBounds);
  }
  else
  {
    cellBounds = bounds;
  }

  int intersects = -1;
  int dim = cell->GetCellDimension();

  if (!this->IntersectsBox(cellBounds[0], cellBounds[1], cellBounds[2], cellBounds[3],
        cellBounds[4], cellBounds[5], useDataBounds))
  {
    intersects = 0; // cell bounding box is outside region
  }
  else if (this->ContainsBox(cellBounds[0], cellBounds[1], cellBounds[2], cellBounds[3],
             cellBounds[4], cellBounds[5], useDataBounds))
  {
    intersects = 1; // cell bounding box is completely inside region
  }
  else
  {
    // quick test - if any of the points are in this region,
    // then it intersects

    vtkPoints* pts = cell->GetPoints();
    vtkIdType npts = pts->GetNumberOfPoints();

    for (i = 0; i < npts; i++)
    {
      double* pt = pts->GetPoint(i);
      if (this->ContainsPoint(pt[0], pt[1], pt[2], useDataBounds))
      {
        intersects = 1;
        break;
      }
    }