Method ReadPointRecordData

IO/LAS/vtkLASReader.cxx:80–156

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//------------------------------------------------------------------------------
void vtkLASReader::ReadPointRecordData(liblas::Reader& reader, vtkPolyData* pointsPolyData)
{
  vtkNew<vtkPoints> points;
  // scalars associated with points
  vtkNew<vtkUnsignedShortArray> color;
  color->SetName("color");
  color->SetNumberOfComponents(3);
  vtkNew<vtkUnsignedShortArray> classification;
  classification->SetName("classification");
  classification->SetNumberOfComponents(1);
  vtkNew<vtkUnsignedShortArray> intensity;
  intensity->SetName("intensity");
  intensity->SetNumberOfComponents(1);

  liblas::Header header = liblas::Header(reader.GetHeader());
  std::valarray<double> scale = { header.GetScaleX(), header.GetScaleY(), header.GetScaleZ() };
  std::valarray<double> offset = { header.GetOffsetX(), header.GetOffsetY(), header.GetOffsetZ() };
  liblas::PointFormatName pointFormat = header.GetDataFormatId();
  int pointRecordsCount = header.GetPointRecordsCount();

  for (int i = 0; i < pointRecordsCount && reader.ReadNextPoint(); i++)
  {
    liblas::Point const& p = reader.GetPoint();
    std::valarray<double> lasPoint = { p.GetX(), p.GetY(), p.GetZ() };
    points->InsertNextPoint(&lasPoint[0]);
    // std::valarray<double> point = lasPoint * scale + offset;
    // We have seen a file where the scaled points were much smaller than the offset
    // So, all points ended up in the same place.
    std::valarray<double> point = lasPoint * scale;
    switch (pointFormat)
    {
      case liblas::ePointFormat2:
      case liblas::ePointFormat3:
      case liblas::ePointFormat5:
      {
        unsigned short c[3];
        c[0] = p.GetColor().GetRed();
        c[1] = p.GetColor().GetGreen();
        c[2] = p.GetColor().GetBlue();
        color->InsertNextTypedTuple(c);
        intensity->InsertNextValue(p.GetIntensity());
      }
      break;

      case liblas::ePointFormat0:
      case liblas::ePointFormat1:
        classification->InsertNextValue(p.GetClassification().GetClass());
        intensity->InsertNextValue(p.GetIntensity());
        break;

      case liblas::ePointFormatUnknown:
      default:
        intensity->InsertNextValue(p.GetIntensity());
        break;
    }
  }

  pointsPolyData->SetPoints(points);