C++ Correspondences::empty方法代碼示例

inline void
pcl::registration::getCorDistMeanStd (const pcl::Correspondences &correspondences, double &mean, double &stddev)
{
  if (correspondences.empty ())
    return;

  double sum = 0, sq_sum = 0;

  for (size_t i = 0; i < correspondences.size (); ++i)
  {
    sum += correspondences[i].distance;
    sq_sum += correspondences[i].distance * correspondences[i].distance;
  }
  mean = sum / static_cast<double> (correspondences.size ());
  double variance = (sq_sum - sum * sum / static_cast<double> (correspondences.size ())) / static_cast<double> (correspondences.size () - 1);
  stddev = sqrt (variance);
}

template <typename PointT> bool
pcl::visualization::ImageViewer::showCorrespondences (
  const pcl::PointCloud<PointT> &source_img,
  const pcl::PointCloud<PointT> &target_img,
  const pcl::Correspondences &correspondences,
  int nth,
  const std::string &layer_id)
{
  if (correspondences.empty ())
  {
    PCL_DEBUG ("[pcl::visualization::ImageViewer::addCorrespondences] An empty set of correspondences given! Nothing to display.\n");
    return (false);
  }

  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  LayerMap::iterator am_it = std::find_if (layer_map_.begin (), layer_map_.end (), LayerComparator (layer_id));
  if (am_it == layer_map_.end ())
  {
    PCL_DEBUG ("[pcl::visualization::ImageViewer::addCorrespondences] No layer with ID='%s' found. Creating new one...\n", layer_id.c_str ());
    am_it = createLayer (layer_id, source_img.width + target_img.width, std::max (source_img.height, target_img.height), 1.0, false);
  }
 
  int src_size = source_img.width * source_img.height * 3;
  int tgt_size = target_img.width * target_img.height * 3;

  // Set window size
  setSize (source_img.width + target_img.width , std::max (source_img.height, target_img.height));

  // Set data size
  if (data_size_ < (src_size + tgt_size))
  {
    data_size_ = src_size + tgt_size;
    data_.reset (new unsigned char[data_size_]);
  }

  // Copy data in VTK format
  int j = 0;
  for (size_t i = 0; i < std::max (source_img.height, target_img.height); ++i)
  {
    // Still need to copy the source?
    if (i < source_img.height)
    {
      for (size_t k = 0; k < source_img.width; ++k)
      {
        data_[j++] = source_img[i * source_img.width + k].r;
        data_[j++] = source_img[i * source_img.width + k].g;
        data_[j++] = source_img[i * source_img.width + k].b;
      }
    }
    else
    {
      memcpy (&data_[j], 0, source_img.width * 3);
      j += source_img.width * 3;
    }

    // Still need to copy the target?
    if (i < source_img.height)
    {
      for (size_t k = 0; k < target_img.width; ++k)
      {
        data_[j++] = target_img[i * source_img.width + k].r;
        data_[j++] = target_img[i * source_img.width + k].g;
        data_[j++] = target_img[i * source_img.width + k].b;
      }
    }
    else
    {
      memcpy (&data_[j], 0, target_img.width * 3);
      j += target_img.width * 3;
    }
  }

  void* data = const_cast<void*> (reinterpret_cast<const void*> (data_.get ()));
  
  vtkSmartPointer<vtkImageData> image = vtkSmartPointer<vtkImageData>::New ();
  image->SetDimensions (source_img.width + target_img.width, std::max (source_img.height, target_img.height), 1);
  image->SetScalarTypeToUnsignedChar ();
  image->SetNumberOfScalarComponents (3);
  image->AllocateScalars ();
  image->GetPointData ()->GetScalars ()->SetVoidArray (data, data_size_, 1);
  vtkSmartPointer<PCLContextImageItem> image_item = vtkSmartPointer<PCLContextImageItem>::New ();
#if ((VTK_MAJOR_VERSION == 5) && (VTK_MINOR_VERSION < 10))
  // Now create filter and set previously created transformation
  algo_->SetInput (image);
  algo_->Update ();
  image_item->set (0, 0, algo_->GetOutput ());
#else
  image_item->set (0, 0, image);
  interactor_style_->adjustCamera (image, ren_);
#endif
  am_it->actor->GetScene ()->AddItem (image_item);
  image_viewer_->SetSize (image->GetDimensions ()[0], image->GetDimensions ()[1]);

  // Draw lines between the best corresponding points
  for (size_t i = 0; i < correspondences.size (); i += nth)
  {
    double r, g, b;
    getRandomColors (r, g, b);
    unsigned char u_r = static_cast<unsigned char> (255.0 * r);
    unsigned char u_g = static_cast<unsigned char> (255.0 * g);
//.........這裏部分代碼省略.........