pcl_visualizer.hpp

/*
 * Software License Agreement (BSD License)
 *
 *  Point Cloud Library (PCL) - www.pointclouds.org
 *  Copyright (c) 2012, Open Perception, Inc.
 *
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *   * Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *   * Redistributions in binary form must reproduce the above
 *     copyright notice, this list of conditions and the following
 *     disclaimer in the documentation and/or other materials provided
 *     with the distribution.
 *   * Neither the name of the copyright holder(s) nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 *  COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 *  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 *  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 *  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 *  ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 *
 */
 
#ifndef PCL_PCL_VISUALIZER_IMPL_H_
#define PCL_PCL_VISUALIZER_IMPL_H_
 
#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkCellArray.h>
#include <vtkLeaderActor2D.h>
#include <vtkVectorText.h>
#include <vtkAlgorithmOutput.h>
#include <vtkFollower.h>
#include <vtkMath.h>
#include <vtkSphereSource.h>
#include <vtkProperty2D.h>
#include <vtkDataSetSurfaceFilter.h>
#include <vtkPointData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkMapper.h>
#include <vtkCellData.h>
#include <vtkDataSetMapper.h>
#include <vtkRenderer.h>
#include <vtkRendererCollection.h>
#include <vtkAppendPolyData.h>
#include <vtkTextProperty.h>
#include <vtkLODActor.h>
#include <vtkLineSource.h>
 
#include <pcl/common/utils.h> // pcl::utils::ignore
#include <pcl/visualization/common/shapes.h>
 
// Support for VTK 7.1 upwards
#ifdef vtkGenericDataArray_h
#define SetTupleValue SetTypedTuple
#define InsertNextTupleValue InsertNextTypedTuple
#define GetTupleValue GetTypedTuple
#endif
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const std::string &id, int viewport)
{
  // Convert the PointCloud to VTK PolyData
  PointCloudGeometryHandlerXYZ<PointT> geometry_handler (cloud);
  return (addPointCloud<PointT> (cloud, geometry_handler, id, viewport));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const PointCloudGeometryHandler<PointT> &geometry_handler,
  const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addPointCloud] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  if (pcl::traits::has_color<PointT>())
  {
    PointCloudColorHandlerRGBField<PointT> color_handler_rgb_field (cloud);
    return (fromHandlersToScreen (geometry_handler, color_handler_rgb_field, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
  }
  PointCloudColorHandlerCustom<PointT> color_handler (cloud, 255, 255, 255);
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const GeometryHandlerConstPtr &geometry_handler,
  const std::string &id, int viewport)
{
  if (contains (id))
  {
    // Here we're just pushing the handlers onto the queue. If needed, something fancier could
    // be done such as checking if a specific handler already exists, etc.
    auto am_it = cloud_actor_map_->find (id);
    am_it->second.geometry_handlers.push_back (geometry_handler);
    return (true);
  }
 
  //PointCloudColorHandlerRandom<PointT> color_handler (cloud);
  PointCloudColorHandlerCustom<PointT> color_handler (cloud, 255, 255, 255);
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const PointCloudColorHandler<PointT> &color_handler,
  const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addPointCloud] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
 
    // Here we're just pushing the handlers onto the queue. If needed, something fancier could
    // be done such as checking if a specific handler already exists, etc.
    //cloud_actor_map_[id].color_handlers.push_back (color_handler);
    //style_->setCloudActorMap (boost::make_shared<CloudActorMap> (cloud_actor_map_));
    return (false);
  }
  // Convert the PointCloud to VTK PolyData
  PointCloudGeometryHandlerXYZ<PointT> geometry_handler (cloud);
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const ColorHandlerConstPtr &color_handler,
  const std::string &id, int viewport)
{
  // Check to see if this entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
  if (am_it != cloud_actor_map_->end ())
  {
    // Here we're just pushing the handlers onto the queue. If needed, something fancier could
    // be done such as checking if a specific handler already exists, etc.
    am_it->second.color_handlers.push_back (color_handler);
    return (true);
  }
 
  PointCloudGeometryHandlerXYZ<PointT> geometry_handler (cloud);
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const GeometryHandlerConstPtr &geometry_handler,
  const ColorHandlerConstPtr &color_handler,
  const std::string &id, int viewport)
{
  // Check to see if this entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
  if (am_it != cloud_actor_map_->end ())
  {
    // Here we're just pushing the handlers onto the queue. If needed, something fancier could
    // be done such as checking if a specific handler already exists, etc.
    am_it->second.geometry_handlers.push_back (geometry_handler);
    am_it->second.color_handlers.push_back (color_handler);
    return (true);
  }
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPointCloud (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const PointCloudColorHandler<PointT> &color_handler,
  const PointCloudGeometryHandler<PointT> &geometry_handler,
  const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addPointCloud] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    // Here we're just pushing the handlers onto the queue. If needed, something fancier could
    // be done such as checking if a specific handler already exists, etc.
    //cloud_actor_map_[id].geometry_handlers.push_back (geometry_handler);
    //cloud_actor_map_[id].color_handlers.push_back (color_handler);
    //style_->setCloudActorMap (boost::make_shared<CloudActorMap> (cloud_actor_map_));
    return (false);
  }
  return (fromHandlersToScreen (geometry_handler, color_handler, id, viewport, cloud->sensor_origin_, cloud->sensor_orientation_));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> void
pcl::visualization::PCLVisualizer::convertPointCloudToVTKPolyData (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  vtkSmartPointer<vtkPolyData> &polydata,
  vtkSmartPointer<vtkIdTypeArray> &initcells)
{
  vtkSmartPointer<vtkCellArray> vertices;
  if (!polydata)
  {
    allocVtkPolyData (polydata);
    vertices = vtkSmartPointer<vtkCellArray>::New ();
    polydata->SetVerts (vertices);
  }
 
  // Create the supporting structures
  vertices = polydata->GetVerts ();
  if (!vertices)
    vertices = vtkSmartPointer<vtkCellArray>::New ();
 
  vtkIdType nr_points = cloud->size ();
  // Create the point set
  vtkSmartPointer<vtkPoints> points = polydata->GetPoints ();
  if (!points)
  {
    points = vtkSmartPointer<vtkPoints>::New ();
    points->SetDataTypeToFloat ();
    polydata->SetPoints (points);
  }
  points->SetNumberOfPoints (nr_points);
 
  // Get a pointer to the beginning of the data array
  float *data = (dynamic_cast<vtkFloatArray*> (points->GetData ()))->GetPointer (0);
 
  // Set the points
  vtkIdType ptr = 0;
  if (cloud->is_dense)
  {
    for (vtkIdType i = 0; i < nr_points; ++i, ptr += 3) {
      std::copy(&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
    }
  }
  else
  {
    vtkIdType j = 0;    // true point index
    for (vtkIdType i = 0; i < nr_points; ++i)
    {
      // Check if the point is invalid
      if (!std::isfinite ((*cloud)[i].x) ||
          !std::isfinite ((*cloud)[i].y) ||
          !std::isfinite ((*cloud)[i].z))
        continue;
 
      std::copy (&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
      j++;
      ptr += 3;
    }
    nr_points = j;
    points->SetNumberOfPoints (nr_points);
  }
 
#ifdef VTK_CELL_ARRAY_V2
  // TODO: Remove when VTK 6,7,8 is unsupported
  pcl::utils::ignore(initcells);
 
  auto numOfCells = vertices->GetNumberOfCells();
 
  // If we have less cells than points, add new cells.
  if (numOfCells < nr_points)
  {
    for (int i = numOfCells; i < nr_points; i++)
    {
      vertices->InsertNextCell(1);
      vertices->InsertCellPoint(i);
    }
  }
  // if we too many cells than points, set size (doesn't free excessive memory)
  else if (numOfCells > nr_points)
  {
    vertices->ResizeExact(nr_points, nr_points);
  }
 
  polydata->SetPoints(points);
  polydata->SetVerts(vertices);
 
#else
  vtkSmartPointer<vtkIdTypeArray> cells = vertices->GetData ();
  updateCells (cells, initcells, nr_points);
 
  // Set the cells and the vertices
  vertices->SetCells (nr_points, cells);
 
  // Set the cell count explicitly as the array doesn't get modified enough so the above method updates accordingly. See #4001 and #3452
  vertices->SetNumberOfCells(nr_points);
#endif
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> void
pcl::visualization::PCLVisualizer::convertPointCloudToVTKPolyData (
  const pcl::visualization::PointCloudGeometryHandler<PointT> &geometry_handler,
  vtkSmartPointer<vtkPolyData> &polydata,
  vtkSmartPointer<vtkIdTypeArray> &initcells)
{
  vtkSmartPointer<vtkCellArray> vertices;
  if (!polydata)
  {
    allocVtkPolyData (polydata);
    vertices = vtkSmartPointer<vtkCellArray>::New ();
    polydata->SetVerts (vertices);
  }
 
  // Use the handler to obtain the geometry
  vtkSmartPointer<vtkPoints> points;
  geometry_handler.getGeometry (points);
  polydata->SetPoints (points);
 
  vtkIdType nr_points = points->GetNumberOfPoints ();
 
  // Create the supporting structures
  vertices = polydata->GetVerts ();
  if (!vertices)
    vertices = vtkSmartPointer<vtkCellArray>::New ();
 
#ifdef VTK_CELL_ARRAY_V2
  // TODO: Remove when VTK 6,7,8 is unsupported
  pcl::utils::ignore(initcells);
 
  auto numOfCells = vertices->GetNumberOfCells();
 
  // If we have less cells than points, add new cells.
  if (numOfCells < nr_points)
  {
    for (int i = numOfCells; i < nr_points; i++)
    {
      vertices->InsertNextCell(1);
      vertices->InsertCellPoint(i);
    }
  }
  // if we too many cells than points, set size (doesn't free excessive memory)
  else if (numOfCells > nr_points)
  {
    vertices->ResizeExact(nr_points, nr_points);
  }
 
  polydata->SetPoints(points);
  polydata->SetVerts(vertices);
 
#else
  vtkSmartPointer<vtkIdTypeArray> cells = vertices->GetData ();
  updateCells (cells, initcells, nr_points);
  // Set the cells and the vertices
  vertices->SetCells (nr_points, cells);
#endif
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPolygon (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  double r, double g, double b, const std::string &id, int viewport)
{
  vtkSmartPointer<vtkDataSet> data = createPolygon<PointT> (cloud);
  if (!data)
    return (false);
 
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = shape_actor_map_->find (id);
  if (am_it != shape_actor_map_->end ())
  {
    vtkSmartPointer<vtkAppendPolyData> all_data = vtkSmartPointer<vtkAppendPolyData>::New ();
    
    // Add old data
    all_data->AddInputData (reinterpret_cast<vtkPolyDataMapper*> ((vtkActor::SafeDownCast (am_it->second))->GetMapper ())->GetInput ());
 
    // Add new data
    vtkSmartPointer<vtkDataSetSurfaceFilter> surface_filter = vtkSmartPointer<vtkDataSetSurfaceFilter>::New ();
    surface_filter->AddInputData (vtkUnstructuredGrid::SafeDownCast (data));
    vtkSmartPointer<vtkPolyData> poly_data = surface_filter->GetOutput ();
    all_data->AddInputData (poly_data);
 
    // Create an Actor
    vtkSmartPointer<vtkActor> actor;
    createActorFromVTKDataSet (all_data->GetOutput (), actor);
    actor->GetProperty ()->SetRepresentationToWireframe ();
    actor->GetProperty ()->SetColor (r, g, b);
    actor->GetMapper ()->ScalarVisibilityOff ();
    removeActorFromRenderer (am_it->second, viewport);
    addActorToRenderer (actor, viewport);
 
    // Save the pointer/ID pair to the global actor map
    (*shape_actor_map_)[id] = actor;
  }
  else
  {
    // Create an Actor
    vtkSmartPointer<vtkActor> actor;
    createActorFromVTKDataSet (data, actor);
    actor->GetProperty ()->SetRepresentationToWireframe ();
    actor->GetProperty ()->SetColor (r, g, b);
    actor->GetMapper ()->ScalarVisibilityOff ();
    addActorToRenderer (actor, viewport);
 
    // Save the pointer/ID pair to the global actor map
    (*shape_actor_map_)[id] = actor;
  }
 
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPolygon (
  const pcl::PlanarPolygon<PointT> &polygon,
  double r, double g, double b, const std::string &id, int viewport)
{
  vtkSmartPointer<vtkDataSet> data = createPolygon<PointT> (polygon);
  if (!data)
    return (false);
 
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = shape_actor_map_->find (id);
  if (am_it != shape_actor_map_->end ())
  {
    vtkSmartPointer<vtkAppendPolyData> all_data = vtkSmartPointer<vtkAppendPolyData>::New ();
 
    // Add old data
    all_data->AddInputData (reinterpret_cast<vtkPolyDataMapper*> ((vtkActor::SafeDownCast (am_it->second))->GetMapper ())->GetInput ());
 
    // Add new data
    vtkSmartPointer<vtkDataSetSurfaceFilter> surface_filter = vtkSmartPointer<vtkDataSetSurfaceFilter>::New ();
    surface_filter->SetInputData (vtkUnstructuredGrid::SafeDownCast (data));
    vtkSmartPointer<vtkPolyData> poly_data = surface_filter->GetOutput ();
    all_data->AddInputData (poly_data);
 
    // Create an Actor
    vtkSmartPointer<vtkActor> actor;
    createActorFromVTKDataSet (all_data->GetOutput (), actor);
    actor->GetProperty ()->SetRepresentationToWireframe ();
    actor->GetProperty ()->SetColor (r, g, b);
    actor->GetMapper ()->ScalarVisibilityOn ();
    actor->GetProperty ()->BackfaceCullingOff ();
    removeActorFromRenderer (am_it->second, viewport);
    addActorToRenderer (actor, viewport);
 
    // Save the pointer/ID pair to the global actor map
    (*shape_actor_map_)[id] = actor;
  }
  else
  {
    // Create an Actor
    vtkSmartPointer<vtkActor> actor;
    createActorFromVTKDataSet (data, actor);
    actor->GetProperty ()->SetRepresentationToWireframe ();
    actor->GetProperty ()->SetColor (r, g, b);
    actor->GetMapper ()->ScalarVisibilityOn ();
    actor->GetProperty ()->BackfaceCullingOff ();
    addActorToRenderer (actor, viewport);
 
    // Save the pointer/ID pair to the global actor map
    (*shape_actor_map_)[id] = actor;
  }
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPolygon (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const std::string &id, int viewport)
{
  return (!addPolygon<PointT> (cloud, 0.5, 0.5, 0.5, id, viewport));
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename P1, typename P2> bool
pcl::visualization::PCLVisualizer::addLine (const P1 &pt1, const P2 &pt2, double r, double g, double b, const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addLine] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkDataSet> data = createLine (pt1.getVector4fMap (), pt2.getVector4fMap ());
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor;
  createActorFromVTKDataSet (data, actor);
  actor->GetProperty ()->SetRepresentationToWireframe ();
  actor->GetProperty ()->SetColor (r, g, b);
  actor->GetMapper ()->ScalarVisibilityOff ();
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*shape_actor_map_)[id] = actor;
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename P1, typename P2> bool
pcl::visualization::PCLVisualizer::addArrow (const P1 &pt1, const P2 &pt2, double r, double g, double b, const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addArrow] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLeaderActor2D> leader = vtkSmartPointer<vtkLeaderActor2D>::New ();
  leader->GetPositionCoordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPositionCoordinate ()->SetValue (pt1.x, pt1.y, pt1.z);
  leader->GetPosition2Coordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPosition2Coordinate ()->SetValue (pt2.x, pt2.y, pt2.z);
  leader->SetArrowStyleToFilled ();
  leader->AutoLabelOn ();
 
  leader->GetProperty ()->SetColor (r, g, b);
  addActorToRenderer (leader, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*shape_actor_map_)[id] = leader;
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename P1, typename P2> bool
pcl::visualization::PCLVisualizer::addArrow (const P1 &pt1, const P2 &pt2, double r, double g, double b, bool display_length, const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addArrow] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLeaderActor2D> leader = vtkSmartPointer<vtkLeaderActor2D>::New ();
  leader->GetPositionCoordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPositionCoordinate ()->SetValue (pt1.x, pt1.y, pt1.z);
  leader->GetPosition2Coordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPosition2Coordinate ()->SetValue (pt2.x, pt2.y, pt2.z);
  leader->SetArrowStyleToFilled ();
  leader->SetArrowPlacementToPoint1 ();
  if (display_length)
    leader->AutoLabelOn ();
  else
    leader->AutoLabelOff ();
 
  leader->GetProperty ()->SetColor (r, g, b);
  addActorToRenderer (leader, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*shape_actor_map_)[id] = leader;
  return (true);
}
////////////////////////////////////////////////////////////////////////////////////////////
template <typename P1, typename P2> bool
pcl::visualization::PCLVisualizer::addArrow (const P1 &pt1, const P2 &pt2,
                                            double r_line, double g_line, double b_line,
                                            double r_text, double g_text, double b_text,
                                            const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addArrow] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLeaderActor2D> leader = vtkSmartPointer<vtkLeaderActor2D>::New ();
  leader->GetPositionCoordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPositionCoordinate ()->SetValue (pt1.x, pt1.y, pt1.z);
  leader->GetPosition2Coordinate ()->SetCoordinateSystemToWorld ();
  leader->GetPosition2Coordinate ()->SetValue (pt2.x, pt2.y, pt2.z);
  leader->SetArrowStyleToFilled ();
  leader->AutoLabelOn ();
 
  leader->GetLabelTextProperty()->SetColor(r_text, g_text, b_text);
  
  leader->GetProperty ()->SetColor (r_line, g_line, b_line);
  addActorToRenderer (leader, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*shape_actor_map_)[id] = leader;
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename P1, typename P2> bool
pcl::visualization::PCLVisualizer::addLine (const P1 &pt1, const P2 &pt2, const std::string &id, int viewport)
{
  return (!addLine (pt1, pt2, 0.5, 0.5, 0.5, id, viewport));
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addSphere (const PointT &center, double radius, double r, double g, double b, const std::string &id, int viewport)
{
  if (contains (id))
  {
    PCL_WARN ("[addSphere] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkSphereSource> data = vtkSmartPointer<vtkSphereSource>::New ();
  data->SetRadius (radius);
  data->SetCenter (static_cast<double>(center.x), static_cast<double>(center.y), static_cast<double>(center.z));
  data->SetPhiResolution (10);
  data->SetThetaResolution (10);
  data->LatLongTessellationOff ();
  data->Update ();
 
  // Setup actor and mapper 
  vtkSmartPointer <vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New ();
  mapper->SetInputConnection (data->GetOutputPort ());
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor = vtkSmartPointer<vtkLODActor>::New ();
  actor->SetMapper (mapper);
  //createActorFromVTKDataSet (data, actor);
  actor->GetProperty ()->SetRepresentationToSurface ();
  actor->GetProperty ()->SetInterpolationToFlat ();
  actor->GetProperty ()->SetColor (r, g, b);
  actor->GetMapper ()->StaticOn ();
  actor->GetMapper ()->ScalarVisibilityOff ();
  actor->GetMapper ()->Update ();
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*shape_actor_map_)[id] = actor;
  return (true);
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addSphere (const PointT &center, double radius, const std::string &id, int viewport)
{
  return (addSphere (center, radius, 0.5, 0.5, 0.5, id, viewport));
}
 
////////////////////////////////////////////////////////////////////////////////////////////
template<typename PointT> bool
pcl::visualization::PCLVisualizer::updateSphere (const PointT &center, double radius, double r, double g, double b, const std::string &id)
{
  if (!contains (id))
  {
    return (false);
  }
 
  //////////////////////////////////////////////////////////////////////////
  // Get the actor pointer
  auto am_it = shape_actor_map_->find (id);
  vtkLODActor* actor = vtkLODActor::SafeDownCast (am_it->second);
  if (!actor)
    return (false);
  vtkAlgorithm *algo = actor->GetMapper ()->GetInputAlgorithm ();
  vtkSphereSource *src = vtkSphereSource::SafeDownCast (algo);
  if (!src)
    return (false);
 
  src->SetCenter (double (center.x), double (center.y), double (center.z));
  src->SetRadius (radius);
  src->Update ();
  actor->GetProperty ()->SetColor (r, g, b);
  actor->Modified ();
 
  return (true);
}
 
//////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addText3D (
  const std::string &text,
  const PointT& position,
  double textScale,
  double r,
  double g,
  double b,
  const std::string &id,
  int viewport)
{
  std::string tid;
  if (id.empty ())
    tid = text;
  else
    tid = id;
 
  if (viewport < 0)
    return false;
 
  // If there is no custom viewport and the viewport number is not 0, exit
  if (rens_->GetNumberOfItems () <= viewport)
  {
    PCL_ERROR ("[addText3D] The viewport [%d] doesn't exist (id <%s>)! \n",
               viewport,
               tid.c_str ());
    return false;
  }
 
  // check all or an individual viewport for a similar id
  rens_->InitTraversal ();
  for (std::size_t i = viewport; rens_->GetNextItem (); ++i)
  {
    const std::string uid = tid + std::string (i, '*');
    if (contains (uid))
    {
      PCL_ERROR ( "[addText3D] The id <%s> already exists in viewport [%d]! \n"
                  "Please choose a different id and retry.\n",
                  tid.c_str (),
                  i);
      return false;
    }
 
    if (viewport > 0)
      break;
  }
 
  vtkSmartPointer<vtkVectorText> textSource = vtkSmartPointer<vtkVectorText>::New ();
  textSource->SetText (text.c_str());
  textSource->Update ();
 
  vtkSmartPointer<vtkPolyDataMapper> textMapper = vtkSmartPointer<vtkPolyDataMapper>::New ();
  textMapper->SetInputConnection (textSource->GetOutputPort ());
 
  // Since each follower may follow a different camera, we need different followers
  rens_->InitTraversal ();
  vtkRenderer* renderer;
  int i = 0;
  while ((renderer = rens_->GetNextItem ()))
  {
    // Should we add the actor to all renderers or just to i-nth renderer?
    if (viewport == 0 || viewport == i)
    {
      vtkSmartPointer<vtkFollower> textActor = vtkSmartPointer<vtkFollower>::New ();
      textActor->SetMapper (textMapper);
      textActor->SetPosition (position.x, position.y, position.z);
      textActor->SetScale (textScale);
      textActor->GetProperty ()->SetColor (r, g, b);
      textActor->SetCamera (renderer->GetActiveCamera ());
 
      renderer->AddActor (textActor);
      
      // Save the pointer/ID pair to the global actor map. If we are saving multiple vtkFollowers
      // for multiple viewport
      const std::string uid = tid + std::string (i, '*');
      (*shape_actor_map_)[uid] = textActor;
    }
 
    ++i;
  }
 
  return (true);
}
 
//////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addText3D (
  const std::string &text,
  const PointT& position,
  double orientation[3],
  double textScale,
  double r,
  double g,
  double b,
  const std::string &id,
  int viewport)
{
  std::string tid;
  if (id.empty ())
    tid = text;
  else
    tid = id;
 
  if (viewport < 0)
    return false;
 
  // If there is no custom viewport and the viewport number is not 0, exit
  if (rens_->GetNumberOfItems () <= viewport)
  {
    PCL_ERROR ("[addText3D] The viewport [%d] doesn't exist (id <%s>)!\n",
               viewport,
               tid.c_str ());
    return false;
  }
 
  // check all or an individual viewport for a similar id
  rens_->InitTraversal ();
  for (std::size_t i = viewport; rens_->GetNextItem (); ++i)
  {
    const std::string uid = tid + std::string (i, '*');
    if (contains (uid))
    {
      PCL_ERROR ( "[addText3D] The id <%s> already exists in viewport [%d]! "
                  "Please choose a different id and retry.\n",
                  tid.c_str (),
                  i);
      return false;
    }
 
    if (viewport > 0)
      break;
  }
 
  vtkSmartPointer<vtkVectorText> textSource = vtkSmartPointer<vtkVectorText>::New ();
  textSource->SetText (text.c_str());
  textSource->Update ();
 
  vtkSmartPointer<vtkPolyDataMapper> textMapper = vtkSmartPointer<vtkPolyDataMapper>::New ();
  textMapper->SetInputConnection (textSource->GetOutputPort ());
 
  vtkSmartPointer<vtkActor> textActor = vtkSmartPointer<vtkActor>::New ();
  textActor->SetMapper (textMapper);
  textActor->SetPosition (position.x, position.y, position.z);
  textActor->SetScale (textScale);
  textActor->GetProperty ()->SetColor (r, g, b);
  textActor->SetOrientation (orientation);
 
  // Save the pointer/ID pair to the global actor map. If we are saving multiple vtkFollowers
  rens_->InitTraversal ();
  int i = 0;
  for ( vtkRenderer* renderer = rens_->GetNextItem ();
        renderer;
        renderer = rens_->GetNextItem (), ++i)
  {
    if (viewport == 0 || viewport == i)
    {
      renderer->AddActor (textActor);
      const std::string uid = tid + std::string (i, '*');
      (*shape_actor_map_)[uid] = textActor;
    }
  }
 
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointNT> bool
pcl::visualization::PCLVisualizer::addPointCloudNormals (
  const typename pcl::PointCloud<PointNT>::ConstPtr &cloud,
  int level, float scale, const std::string &id, int viewport)
{
  return (addPointCloudNormals<PointNT, PointNT> (cloud, cloud, level, scale, id, viewport));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT, typename PointNT> bool
pcl::visualization::PCLVisualizer::addPointCloudNormals (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const typename pcl::PointCloud<PointNT>::ConstPtr &normals,
  int level, float scale,
  const std::string &id, int viewport)
{
  if (normals->size () != cloud->size ())
  {
    PCL_ERROR ("[addPointCloudNormals] The number of points differs from the number of normals!\n");
    return (false);
  }
 
  if (normals->empty ())
  {
    PCL_WARN ("[addPointCloudNormals] An empty normal cloud is given! Nothing to display.\n");
    return (false);
  }
 
  if (contains (id))
  {
    PCL_WARN ("[addPointCloudNormals] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
  vtkSmartPointer<vtkCellArray> lines = vtkSmartPointer<vtkCellArray>::New();
 
  points->SetDataTypeToFloat ();
  vtkSmartPointer<vtkFloatArray> data = vtkSmartPointer<vtkFloatArray>::New ();
  data->SetNumberOfComponents (3);
 
 
  vtkIdType nr_normals = 0;
  float* pts = nullptr;
 
  // If the cloud is organized, then distribute the normal step in both directions
  if (cloud->isOrganized () && normals->isOrganized ())
  {
    auto point_step = static_cast<vtkIdType> (sqrt (static_cast<double>(level)));
    nr_normals = (static_cast<vtkIdType> ((cloud->width - 1)/ point_step) + 1) *
                 (static_cast<vtkIdType> ((cloud->height - 1) / point_step) + 1);
    pts = new float[2 * nr_normals * 3];
 
    vtkIdType cell_count = 0;
    for (vtkIdType y = 0; y < normals->height; y += point_step)
      for (vtkIdType x = 0; x < normals->width; x += point_step)
      {
        PointT p = (*cloud)(x, y);
        if (!pcl::isFinite(p) || !pcl::isNormalFinite((*normals)(x, y)))
          continue;
        p.x += (*normals)(x, y).normal[0] * scale;
        p.y += (*normals)(x, y).normal[1] * scale;
        p.z += (*normals)(x, y).normal[2] * scale;
 
        pts[2 * cell_count * 3 + 0] = (*cloud)(x, y).x;
        pts[2 * cell_count * 3 + 1] = (*cloud)(x, y).y;
        pts[2 * cell_count * 3 + 2] = (*cloud)(x, y).z;
        pts[2 * cell_count * 3 + 3] = p.x;
        pts[2 * cell_count * 3 + 4] = p.y;
        pts[2 * cell_count * 3 + 5] = p.z;
 
        lines->InsertNextCell (2);
        lines->InsertCellPoint (2 * cell_count);
        lines->InsertCellPoint (2 * cell_count + 1);
        cell_count ++;
    }
  }
  else
  {
    nr_normals = (cloud->size () - 1) / level + 1 ;
    pts = new float[2 * nr_normals * 3];
 
    for (vtkIdType i = 0, j = 0; (j < nr_normals) && (i < static_cast<vtkIdType>(cloud->size())); i += level)
    {
      if (!pcl::isFinite((*cloud)[i]) || !pcl::isNormalFinite((*normals)[i]))
        continue;
      PointT p = (*cloud)[i];
      p.x += (*normals)[i].normal[0] * scale;
      p.y += (*normals)[i].normal[1] * scale;
      p.z += (*normals)[i].normal[2] * scale;
 
      pts[2 * j * 3 + 0] = (*cloud)[i].x;
      pts[2 * j * 3 + 1] = (*cloud)[i].y;
      pts[2 * j * 3 + 2] = (*cloud)[i].z;
      pts[2 * j * 3 + 3] = p.x;
      pts[2 * j * 3 + 4] = p.y;
      pts[2 * j * 3 + 5] = p.z;
 
      lines->InsertNextCell (2);
      lines->InsertCellPoint (2 * j);
      lines->InsertCellPoint (2 * j + 1);
      ++j;
    }
  }
 
  data->SetArray (&pts[0], 2 * nr_normals * 3, 0, vtkFloatArray::VTK_DATA_ARRAY_DELETE);
  points->SetData (data);
 
  vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
  polyData->SetPoints (points);
  polyData->SetLines (lines);
 
  vtkSmartPointer<vtkDataSetMapper> mapper = vtkSmartPointer<vtkDataSetMapper>::New ();
  mapper->SetInputData (polyData);
  mapper->SetColorModeToMapScalars();
  mapper->SetScalarModeToUsePointData();
 
  // create actor
  vtkSmartPointer<vtkLODActor> actor = vtkSmartPointer<vtkLODActor>::New ();
  actor->SetMapper (mapper);
 
  // Use cloud view point info
  vtkSmartPointer<vtkMatrix4x4> transformation = vtkSmartPointer<vtkMatrix4x4>::New ();
  convertToVtkMatrix (cloud->sensor_origin_, cloud->sensor_orientation_, transformation);
  actor->SetUserMatrix (transformation);
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*cloud_actor_map_)[id].actor = actor;
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointNT> bool
pcl::visualization::PCLVisualizer::addPointCloudPrincipalCurvatures (
  const typename pcl::PointCloud<PointNT>::ConstPtr &cloud,
  const pcl::PointCloud<pcl::PrincipalCurvatures>::ConstPtr &pcs,
  int level, float scale,
  const std::string &id, int viewport)
{
  return (addPointCloudPrincipalCurvatures<PointNT, PointNT> (cloud, cloud, pcs, level, scale, id, viewport));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT, typename PointNT> bool
pcl::visualization::PCLVisualizer::addPointCloudPrincipalCurvatures (
  const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
  const typename pcl::PointCloud<PointNT>::ConstPtr &normals,
  const pcl::PointCloud<pcl::PrincipalCurvatures>::ConstPtr &pcs,
  int level, float scale,
  const std::string &id, int viewport)
{
  if (pcs->size () != cloud->size () || normals->size () != cloud->size ())
  {
    pcl::console::print_error ("[addPointCloudPrincipalCurvatures] The number of points differs from the number of principal curvatures/normals!\n");
    return (false);
  }
 
  if (contains (id))
  {
    PCL_WARN ("[addPointCloudPrincipalCurvatures] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkAppendPolyData> polydata_1 = vtkSmartPointer<vtkAppendPolyData>::New ();
  vtkSmartPointer<vtkAppendPolyData> polydata_2 = vtkSmartPointer<vtkAppendPolyData>::New ();
 
  // Setup two colors - one for each line
  unsigned char green[3] = {0, 255, 0};
  unsigned char blue[3] = {0, 0, 255};
 
  // Setup the colors array
  vtkSmartPointer<vtkUnsignedCharArray> line_1_colors =vtkSmartPointer<vtkUnsignedCharArray>::New ();
  line_1_colors->SetNumberOfComponents (3);
  line_1_colors->SetName ("Colors");
  vtkSmartPointer<vtkUnsignedCharArray> line_2_colors =vtkSmartPointer<vtkUnsignedCharArray>::New ();
  line_2_colors->SetNumberOfComponents (3);
  line_2_colors->SetName ("Colors");
 
  // Create the first sets of lines
  for (std::size_t i = 0; i < cloud->size (); i+=level)
  {
    PointT p = (*cloud)[i];
    p.x += ((*pcs)[i].pc1 * (*pcs)[i].principal_curvature[0]) * scale;
    p.y += ((*pcs)[i].pc1 * (*pcs)[i].principal_curvature[1]) * scale;
    p.z += ((*pcs)[i].pc1 * (*pcs)[i].principal_curvature[2]) * scale;
 
    vtkSmartPointer<vtkLineSource> line_1 = vtkSmartPointer<vtkLineSource>::New ();
    line_1->SetPoint1 ((*cloud)[i].x, (*cloud)[i].y, (*cloud)[i].z);
    line_1->SetPoint2 (p.x, p.y, p.z);
    line_1->Update ();
    polydata_1->AddInputData (line_1->GetOutput ());
    line_1_colors->InsertNextTupleValue (green);
  }
  polydata_1->Update ();
  vtkSmartPointer<vtkPolyData> line_1_data = polydata_1->GetOutput ();
  line_1_data->GetCellData ()->SetScalars (line_1_colors);
 
  // Create the second sets of lines
  for (std::size_t i = 0; i < cloud->size (); i += level)
  {
    Eigen::Vector3f pc ((*pcs)[i].principal_curvature[0],
                        (*pcs)[i].principal_curvature[1],
                        (*pcs)[i].principal_curvature[2]);
    Eigen::Vector3f normal ((*normals)[i].normal[0],
                            (*normals)[i].normal[1],
                            (*normals)[i].normal[2]);
    Eigen::Vector3f pc_c = pc.cross (normal);
 
    PointT p = (*cloud)[i];
    p.x += ((*pcs)[i].pc2 * pc_c[0]) * scale;
    p.y += ((*pcs)[i].pc2 * pc_c[1]) * scale;
    p.z += ((*pcs)[i].pc2 * pc_c[2]) * scale;
 
    vtkSmartPointer<vtkLineSource> line_2 = vtkSmartPointer<vtkLineSource>::New ();
    line_2->SetPoint1 ((*cloud)[i].x, (*cloud)[i].y, (*cloud)[i].z);
    line_2->SetPoint2 (p.x, p.y, p.z);
    line_2->Update ();
    polydata_2->AddInputData (line_2->GetOutput ());
 
    line_2_colors->InsertNextTupleValue (blue);
  }
  polydata_2->Update ();
  vtkSmartPointer<vtkPolyData> line_2_data = polydata_2->GetOutput ();
  line_2_data->GetCellData ()->SetScalars (line_2_colors);
 
  // Assemble the two sets of lines
  vtkSmartPointer<vtkAppendPolyData> alldata = vtkSmartPointer<vtkAppendPolyData>::New ();
  alldata->AddInputData (line_1_data);
  alldata->AddInputData (line_2_data);
  alldata->Update ();
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor;
  createActorFromVTKDataSet (alldata->GetOutput (), actor);
  actor->GetMapper ()->SetScalarModeToUseCellData ();
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  CloudActor act;
  act.actor = actor;
  (*cloud_actor_map_)[id] = act;
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT, typename GradientT> bool
pcl::visualization::PCLVisualizer::addPointCloudIntensityGradients (
    const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
    const typename pcl::PointCloud<GradientT>::ConstPtr &gradients,
    int level, double scale,
    const std::string &id, int viewport)
{
  if (gradients->size () != cloud->size ())
  {
    PCL_ERROR ("[addPointCloudGradients] The number of points differs from the number of gradients!\n");
    return (false);
  }
  if (contains (id))
  {
    PCL_WARN ("[addPointCloudGradients] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New();
  vtkSmartPointer<vtkCellArray> lines = vtkSmartPointer<vtkCellArray>::New();
 
  points->SetDataTypeToFloat ();
  vtkSmartPointer<vtkFloatArray> data = vtkSmartPointer<vtkFloatArray>::New ();
  data->SetNumberOfComponents (3);
 
  vtkIdType nr_gradients = (cloud->size () - 1) / level + 1 ;
  float* pts = new float[2 * nr_gradients * 3];
 
  for (vtkIdType i = 0, j = 0; j < nr_gradients; j++, i = j * level)
  {
    PointT p = (*cloud)[i];
    p.x += (*gradients)[i].gradient[0] * scale;
    p.y += (*gradients)[i].gradient[1] * scale;
    p.z += (*gradients)[i].gradient[2] * scale;
 
    pts[2 * j * 3 + 0] = (*cloud)[i].x;
    pts[2 * j * 3 + 1] = (*cloud)[i].y;
    pts[2 * j * 3 + 2] = (*cloud)[i].z;
    pts[2 * j * 3 + 3] = p.x;
    pts[2 * j * 3 + 4] = p.y;
    pts[2 * j * 3 + 5] = p.z;
 
    lines->InsertNextCell(2);
    lines->InsertCellPoint(2*j);
    lines->InsertCellPoint(2*j+1);
  }
 
  data->SetArray (&pts[0], 2 * nr_gradients * 3, 0, vtkFloatArray::VTK_DATA_ARRAY_DELETE);
  points->SetData (data);
 
  vtkSmartPointer<vtkPolyData> polyData = vtkSmartPointer<vtkPolyData>::New();
  polyData->SetPoints(points);
  polyData->SetLines(lines);
 
  vtkSmartPointer<vtkDataSetMapper> mapper = vtkSmartPointer<vtkDataSetMapper>::New ();
  mapper->SetInputData (polyData);
  mapper->SetColorModeToMapScalars();
  mapper->SetScalarModeToUsePointData();
 
  // create actor
  vtkSmartPointer<vtkLODActor> actor = vtkSmartPointer<vtkLODActor>::New ();
  actor->SetMapper (mapper);
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  (*cloud_actor_map_)[id].actor = actor;
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addCorrespondences (
  const typename pcl::PointCloud<PointT>::ConstPtr &source_points,
  const typename pcl::PointCloud<PointT>::ConstPtr &target_points,
  const std::vector<int> &correspondences,
  const std::string &id,
  int viewport)
{
  pcl::Correspondences corrs;
  corrs.resize (correspondences.size ());
 
  std::size_t index = 0;
  for (auto &corr : corrs)
  {
    corr.index_query = index;
    corr.index_match = correspondences[index];
    index++;
  }
 
  return (addCorrespondences<PointT> (source_points, target_points, corrs, id, viewport));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addCorrespondences (
  const typename pcl::PointCloud<PointT>::ConstPtr &source_points,
  const typename pcl::PointCloud<PointT>::ConstPtr &target_points,
  const pcl::Correspondences &correspondences,
  int nth,
  const std::string &id,
  int viewport,
  bool overwrite)
{
  if (correspondences.empty ())
  {
    PCL_DEBUG ("[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?)
  auto am_it = shape_actor_map_->find (id);
  if (am_it != shape_actor_map_->end () && !overwrite)
  {
    PCL_WARN ("[addCorrespondences] A set of correspondences with id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
  if (am_it == shape_actor_map_->end () && overwrite)
  {
    overwrite = false; // Correspondences doesn't exist, add them instead of updating them
  }
 
  int n_corr = static_cast<int>(correspondences.size () / nth);
  vtkSmartPointer<vtkPolyData> line_data = vtkSmartPointer<vtkPolyData>::New ();
 
  // Prepare colors
  vtkSmartPointer<vtkUnsignedCharArray> line_colors = vtkSmartPointer<vtkUnsignedCharArray>::New ();
  line_colors->SetNumberOfComponents (3);
  line_colors->SetName ("Colors");
  line_colors->SetNumberOfTuples (n_corr);
 
  // Prepare coordinates
  vtkSmartPointer<vtkPoints> line_points = vtkSmartPointer<vtkPoints>::New ();
  line_points->SetNumberOfPoints (2 * n_corr);
 
  vtkSmartPointer<vtkIdTypeArray> line_cells_id = vtkSmartPointer<vtkIdTypeArray>::New ();
  line_cells_id->SetNumberOfComponents (3);
  line_cells_id->SetNumberOfTuples (n_corr);
  vtkIdType *line_cell_id = line_cells_id->GetPointer (0);
  vtkSmartPointer<vtkCellArray> line_cells = vtkSmartPointer<vtkCellArray>::New ();
 
  vtkSmartPointer<vtkFloatArray> line_tcoords = vtkSmartPointer<vtkFloatArray>::New ();
  line_tcoords->SetNumberOfComponents (1);
  line_tcoords->SetNumberOfTuples (n_corr * 2);
  line_tcoords->SetName ("Texture Coordinates");
 
  double tc[3] = {0.0, 0.0, 0.0};
 
  Eigen::Affine3f source_transformation;
  source_transformation.linear () = source_points->sensor_orientation_.matrix ();
  source_transformation.translation () = source_points->sensor_origin_.head (3);
  Eigen::Affine3f target_transformation;
  target_transformation.linear () = target_points->sensor_orientation_.matrix ();
  target_transformation.translation () = target_points->sensor_origin_.head (3);
 
  int j = 0;
  // Draw lines between the best corresponding points
  for (std::size_t i = 0; i < correspondences.size (); i += nth, ++j)
  {
    if (correspondences[i].index_match == UNAVAILABLE)
    {
      PCL_WARN ("[addCorrespondences] No valid index_match for correspondence %d\n", i);
      continue;
    }
 
    PointT p_src ((*source_points)[correspondences[i].index_query]);
    PointT p_tgt ((*target_points)[correspondences[i].index_match]);
 
    p_src.getVector3fMap () = source_transformation * p_src.getVector3fMap ();
    p_tgt.getVector3fMap () = target_transformation * p_tgt.getVector3fMap ();
 
    int id1 = j * 2 + 0, id2 = j * 2 + 1;
    // Set the points
    line_points->SetPoint (id1, p_src.x, p_src.y, p_src.z);
    line_points->SetPoint (id2, p_tgt.x, p_tgt.y, p_tgt.z);
    // Set the cell ID
    *line_cell_id++ = 2;
    *line_cell_id++ = id1;
    *line_cell_id++ = id2;
    // Set the texture coords
    tc[0] = 0.; line_tcoords->SetTuple (id1, tc);
    tc[0] = 1.; line_tcoords->SetTuple (id2, tc);
 
    float rgb[3];
    rgb[0] = vtkMath::Random (32, 255); // min / max
    rgb[1] = vtkMath::Random (32, 255);
    rgb[2] = vtkMath::Random (32, 255);
    line_colors->InsertTuple (i, rgb);
  }
  line_colors->SetNumberOfTuples (j);
  line_cells_id->SetNumberOfTuples (j);
  line_cells->SetCells (n_corr, line_cells_id);
  line_points->SetNumberOfPoints (j*2);
  line_tcoords->SetNumberOfTuples (j*2);
 
  // Fill in the lines
  line_data->SetPoints (line_points);
  line_data->SetLines (line_cells);
  line_data->GetPointData ()->SetTCoords (line_tcoords);
  line_data->GetCellData ()->SetScalars (line_colors);
 
  // Create an Actor
  if (!overwrite)
  {
    vtkSmartPointer<vtkLODActor> actor;
    createActorFromVTKDataSet (line_data, actor);
    actor->GetProperty ()->SetRepresentationToWireframe ();
    actor->GetProperty ()->SetOpacity (0.5);
    addActorToRenderer (actor, viewport);
 
    // Save the pointer/ID pair to the global actor map
    (*shape_actor_map_)[id] = actor;
  }
  else
  {
    vtkSmartPointer<vtkLODActor> actor = vtkLODActor::SafeDownCast (am_it->second);
    if (!actor)
      return (false);
    // Update the mapper
    reinterpret_cast<vtkPolyDataMapper*> (actor->GetMapper ())->SetInputData (line_data);
  }
 
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::updateCorrespondences (
  const typename pcl::PointCloud<PointT>::ConstPtr &source_points,
  const typename pcl::PointCloud<PointT>::ConstPtr &target_points,
  const pcl::Correspondences &correspondences,
  int nth,
  const std::string &id,
  int viewport)
{
  return (addCorrespondences<PointT> (source_points, target_points, correspondences, nth, id, viewport, true));
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::fromHandlersToScreen (
  const PointCloudGeometryHandler<PointT> &geometry_handler,
  const PointCloudColorHandler<PointT> &color_handler,
  const std::string &id,
  int viewport,
  const Eigen::Vector4f& sensor_origin,
  const Eigen::Quaternion<float>& sensor_orientation)
{
  if (!geometry_handler.isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid geometry handler (%s)!\n", id.c_str (), geometry_handler.getName ().c_str ());
    return (false);
  }
 
  if (!color_handler.isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid color handler (%s)!\n", id.c_str (), color_handler.getName ().c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkPolyData> polydata;
  vtkSmartPointer<vtkIdTypeArray> initcells;
  // Convert the PointCloud to VTK PolyData
  convertPointCloudToVTKPolyData<PointT> (geometry_handler, polydata, initcells);
 
  // Get the colors from the handler
  bool has_colors = false;
  double minmax[2];
  if (auto scalars = color_handler.getColor ())
  {
    polydata->GetPointData ()->SetScalars (scalars);
    scalars->GetRange (minmax);
    has_colors = true;
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor;
  createActorFromVTKDataSet (polydata, actor);
  if (has_colors)
    actor->GetMapper ()->SetScalarRange (minmax);
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  CloudActor& cloud_actor = (*cloud_actor_map_)[id];
  cloud_actor.actor = actor;
  cloud_actor.cells = initcells;
 
  // Save the viewpoint transformation matrix to the global actor map
  vtkSmartPointer<vtkMatrix4x4> transformation = vtkSmartPointer<vtkMatrix4x4>::New();
  convertToVtkMatrix (sensor_origin, sensor_orientation, transformation);
  cloud_actor.viewpoint_transformation_ = transformation;
  cloud_actor.actor->SetUserMatrix (transformation);
  cloud_actor.actor->Modified ();
 
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::fromHandlersToScreen (
  const PointCloudGeometryHandler<PointT> &geometry_handler,
  const ColorHandlerConstPtr &color_handler,
  const std::string &id,
  int viewport,
  const Eigen::Vector4f& sensor_origin,
  const Eigen::Quaternion<float>& sensor_orientation)
{
  if (!geometry_handler.isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid geometry handler (%s)!\n", id.c_str (), geometry_handler.getName ().c_str ());
    return (false);
  }
 
  if (!color_handler->isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid color handler (%s)!\n", id.c_str (), color_handler->getName ().c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkPolyData> polydata;
  vtkSmartPointer<vtkIdTypeArray> initcells;
  // Convert the PointCloud to VTK PolyData
  convertPointCloudToVTKPolyData<PointT> (geometry_handler, polydata, initcells);
  // use the given geometry handler
 
  // Get the colors from the handler
  bool has_colors = false;
  double minmax[2];
  if (auto scalars = color_handler->getColor ())
  {
    polydata->GetPointData ()->SetScalars (scalars);
    scalars->GetRange (minmax);
    has_colors = true;
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor;
  createActorFromVTKDataSet (polydata, actor);
  if (has_colors)
    actor->GetMapper ()->SetScalarRange (minmax);
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  CloudActor& cloud_actor = (*cloud_actor_map_)[id];
  cloud_actor.actor = actor;
  cloud_actor.cells = initcells;
  cloud_actor.color_handlers.push_back (color_handler);
 
  // Save the viewpoint transformation matrix to the global actor map
  vtkSmartPointer<vtkMatrix4x4> transformation = vtkSmartPointer<vtkMatrix4x4>::New();
  convertToVtkMatrix (sensor_origin, sensor_orientation, transformation);
  cloud_actor.viewpoint_transformation_ = transformation;
  cloud_actor.actor->SetUserMatrix (transformation);
  cloud_actor.actor->Modified ();
 
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::fromHandlersToScreen (
  const GeometryHandlerConstPtr &geometry_handler,
  const PointCloudColorHandler<PointT> &color_handler,
  const std::string &id,
  int viewport,
  const Eigen::Vector4f& sensor_origin,
  const Eigen::Quaternion<float>& sensor_orientation)
{
  if (!geometry_handler->isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid geometry handler (%s)!\n", id.c_str (), geometry_handler->getName ().c_str ());
    return (false);
  }
 
  if (!color_handler.isCapable ())
  {
    PCL_WARN ("[fromHandlersToScreen] PointCloud <%s> requested with an invalid color handler (%s)!\n", id.c_str (), color_handler.getName ().c_str ());
    return (false);
  }
 
  vtkSmartPointer<vtkPolyData> polydata;
  vtkSmartPointer<vtkIdTypeArray> initcells;
  // Convert the PointCloud to VTK PolyData
  convertPointCloudToVTKPolyData (geometry_handler, polydata, initcells);
  // use the given geometry handler
 
  // Get the colors from the handler
  bool has_colors = false;
  double minmax[2];
  if (auto scalars = color_handler.getColor ())
  {
    polydata->GetPointData ()->SetScalars (scalars);
    scalars->GetRange (minmax);
    has_colors = true;
  }
 
  // Create an Actor
  vtkSmartPointer<vtkLODActor> actor;
  createActorFromVTKDataSet (polydata, actor);
  if (has_colors)
    actor->GetMapper ()->SetScalarRange (minmax);
 
  // Add it to all renderers
  addActorToRenderer (actor, viewport);
 
  // Save the pointer/ID pair to the global actor map
  CloudActor& cloud_actor = (*cloud_actor_map_)[id];
  cloud_actor.actor = actor;
  cloud_actor.cells = initcells;
  cloud_actor.geometry_handlers.push_back (geometry_handler);
 
  // Save the viewpoint transformation matrix to the global actor map
  vtkSmartPointer<vtkMatrix4x4> transformation = vtkSmartPointer<vtkMatrix4x4>::New ();
  convertToVtkMatrix (sensor_origin, sensor_orientation, transformation);
  cloud_actor.viewpoint_transformation_ = transformation;
  cloud_actor.actor->SetUserMatrix (transformation);
  cloud_actor.actor->Modified ();
 
  return (true);
}
 
//////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::updatePointCloud (const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
                                                     const std::string &id)
{
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
 
  if (am_it == cloud_actor_map_->end ())
    return (false);
 
  vtkSmartPointer<vtkPolyData> polydata = reinterpret_cast<vtkPolyDataMapper*>(am_it->second.actor->GetMapper ())->GetInput ();
  if (!polydata)
      return false;
  // Convert the PointCloud to VTK PolyData
  convertPointCloudToVTKPolyData<PointT> (cloud, polydata, am_it->second.cells);
 
  // Set scalars to blank, since there is no way we can update them here.
  vtkSmartPointer<vtkDataArray> scalars;
  polydata->GetPointData ()->SetScalars (scalars);
  double minmax[2];
  minmax[0] = std::numeric_limits<double>::min ();
  minmax[1] = std::numeric_limits<double>::max ();
  am_it->second.actor->GetMapper ()->SetScalarRange (minmax);
 
  // Update the mapper
  reinterpret_cast<vtkPolyDataMapper*> (am_it->second.actor->GetMapper ())->SetInputData (polydata);
  return (true);
}
 
/////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::updatePointCloud (const typename pcl::PointCloud<PointT>::ConstPtr &,
                                                     const PointCloudGeometryHandler<PointT> &geometry_handler,
                                                     const std::string &id)
{
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
 
  if (am_it == cloud_actor_map_->end ())
    return (false);
 
  vtkSmartPointer<vtkPolyData> polydata = reinterpret_cast<vtkPolyDataMapper*>(am_it->second.actor->GetMapper ())->GetInput ();
  if (!polydata)
    return (false);
  // Convert the PointCloud to VTK PolyData
  convertPointCloudToVTKPolyData (geometry_handler, polydata, am_it->second.cells);
 
  // Set scalars to blank, since there is no way we can update them here.
  vtkSmartPointer<vtkDataArray> scalars;
  polydata->GetPointData ()->SetScalars (scalars);
  double minmax[2];
  minmax[0] = std::numeric_limits<double>::min ();
  minmax[1] = std::numeric_limits<double>::max ();
  am_it->second.actor->GetMapper ()->SetScalarRange (minmax);
 
  // Update the mapper
  reinterpret_cast<vtkPolyDataMapper*> (am_it->second.actor->GetMapper ())->SetInputData (polydata);
  return (true);
}
 
 
/////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::updatePointCloud (const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
                                                     const PointCloudColorHandler<PointT> &color_handler,
                                                     const std::string &id)
{
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
 
  if (am_it == cloud_actor_map_->end ())
    return (false);
 
  // Get the current poly data
  vtkSmartPointer<vtkPolyData> polydata = reinterpret_cast<vtkPolyDataMapper*>(am_it->second.actor->GetMapper ())->GetInput ();
  if (!polydata)
    return (false);
 
  convertPointCloudToVTKPolyData<PointT>(cloud, polydata, am_it->second.cells);
 
  // Get the colors from the handler
  bool has_colors = false;
  double minmax[2];
  if (auto scalars = color_handler.getColor ())
  {
    // Update the data
    polydata->GetPointData ()->SetScalars (scalars);
    scalars->GetRange (minmax);
    has_colors = true;
  }
 
  if (has_colors)
    am_it->second.actor->GetMapper ()->SetScalarRange (minmax);
 
  // Update the mapper
  reinterpret_cast<vtkPolyDataMapper*> (am_it->second.actor->GetMapper ())->SetInputData (polydata);
  return (true);
}
 
/////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::addPolygonMesh (
    const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
    const std::vector<pcl::Vertices> &vertices,
    const std::string &id,
    int viewport)
{
  if (vertices.empty () || cloud->points.empty ())
    return (false);
 
  if (contains (id))
  {
    PCL_WARN ("[addPolygonMesh] The id <%s> already exists! Please choose a different id and retry.\n", id.c_str ());
    return (false);
  }
 
  int rgb_idx = -1;
  std::vector<pcl::PCLPointField> fields;
  vtkSmartPointer<vtkUnsignedCharArray> colors;
  rgb_idx = pcl::getFieldIndex<PointT> ("rgb", fields);
  if (rgb_idx == -1)
    rgb_idx = pcl::getFieldIndex<PointT> ("rgba", fields);
  if (rgb_idx != -1)
  {
    colors = vtkSmartPointer<vtkUnsignedCharArray>::New ();
    colors->SetNumberOfComponents (3);
    colors->SetName ("Colors");
    std::uint32_t offset = fields[rgb_idx].offset;
    for (std::size_t i = 0; i < cloud->size (); ++i)
    {
      if (!isFinite ((*cloud)[i]))
        continue;
      const auto* const rgb_data = reinterpret_cast<const pcl::RGB*>(reinterpret_cast<const char*> (&(*cloud)[i]) + offset);
      unsigned char color[3];
      color[0] = rgb_data->r;
      color[1] = rgb_data->g;
      color[2] = rgb_data->b;
      colors->InsertNextTupleValue (color);
    }
  }
 
  // Create points from polyMesh.cloud
  vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New ();
  vtkIdType nr_points = cloud->size ();
  points->SetNumberOfPoints (nr_points);
  vtkSmartPointer<vtkLODActor> actor;
 
  // Get a pointer to the beginning of the data array
  float *data = dynamic_cast<vtkFloatArray*> (points->GetData ())->GetPointer (0);
 
  vtkIdType ptr = 0;
  std::vector<int> lookup;
  // If the dataset is dense (no NaNs)
  if (cloud->is_dense)
  {
    for (vtkIdType i = 0; i < nr_points; ++i, ptr += 3) {
      std::copy(&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
    }
  }
  else
  {
    lookup.resize (nr_points);
    vtkIdType j = 0;    // true point index
    for (vtkIdType i = 0; i < nr_points; ++i)
    {
      // Check if the point is invalid
      if (!isFinite ((*cloud)[i]))
        continue;
 
      lookup[i] = static_cast<int> (j);
      std::copy (&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
      j++;
      ptr += 3;
    }
    nr_points = j;
    points->SetNumberOfPoints (nr_points);
  }
 
  // Get the maximum size of a polygon
  int max_size_of_polygon = -1;
  for (const auto &vertex : vertices)
    if (max_size_of_polygon < static_cast<int> (vertex.vertices.size ()))
      max_size_of_polygon = static_cast<int> (vertex.vertices.size ());
 
  if (vertices.size () > 1)
  {
    // Create polys from polyMesh.polygons
    vtkSmartPointer<vtkCellArray> cell_array = vtkSmartPointer<vtkCellArray>::New ();
    
    const auto idx = details::fillCells(lookup,vertices,cell_array, max_size_of_polygon);
 
    vtkSmartPointer<vtkPolyData> polydata;
    allocVtkPolyData (polydata);
    cell_array->GetData ()->SetNumberOfValues (idx);
    cell_array->Squeeze ();
    polydata->SetPolys (cell_array);
    polydata->SetPoints (points);
  
    if (colors)
      polydata->GetPointData ()->SetScalars (colors);
 
    createActorFromVTKDataSet (polydata, actor, false);
  }
  else
  {
    vtkSmartPointer<vtkPolygon> polygon = vtkSmartPointer<vtkPolygon>::New ();
    std::size_t n_points = vertices[0].vertices.size ();
    polygon->GetPointIds ()->SetNumberOfIds (n_points - 1);
 
    if (!lookup.empty ())
    {
      for (std::size_t j = 0; j < (n_points - 1); ++j)
        polygon->GetPointIds ()->SetId (j, lookup[vertices[0].vertices[j]]);
    }
    else
    {
      for (std::size_t j = 0; j < (n_points - 1); ++j)
        polygon->GetPointIds ()->SetId (j, vertices[0].vertices[j]);
    }
    vtkSmartPointer<vtkUnstructuredGrid> poly_grid;
    allocVtkUnstructuredGrid (poly_grid);
    poly_grid->Allocate (1, 1);
    poly_grid->InsertNextCell (polygon->GetCellType (), polygon->GetPointIds ());
    poly_grid->SetPoints (points);
    if (colors)
      poly_grid->GetPointData ()->SetScalars (colors);
 
    createActorFromVTKDataSet (poly_grid, actor, false);
  }
  addActorToRenderer (actor, viewport);
  actor->GetProperty ()->SetRepresentationToSurface ();
  // Backface culling renders the visualization slower, but guarantees that we see all triangles
  actor->GetProperty ()->BackfaceCullingOff ();
  actor->GetProperty ()->SetInterpolationToFlat ();
  actor->GetProperty ()->EdgeVisibilityOff ();
  actor->GetProperty ()->ShadingOff ();
 
  // Save the pointer/ID pair to the global actor map
  (*cloud_actor_map_)[id].actor = actor;
 
  // Save the viewpoint transformation matrix to the global actor map
  vtkSmartPointer<vtkMatrix4x4> transformation = vtkSmartPointer<vtkMatrix4x4>::New();
  convertToVtkMatrix (cloud->sensor_origin_, cloud->sensor_orientation_, transformation);
  (*cloud_actor_map_)[id].viewpoint_transformation_ = transformation;
 
  return (true);
}
 
/////////////////////////////////////////////////////////////////////////////////////////////
template <typename PointT> bool
pcl::visualization::PCLVisualizer::updatePolygonMesh (
    const typename pcl::PointCloud<PointT>::ConstPtr &cloud,
    const std::vector<pcl::Vertices> &verts,
    const std::string &id)
{
  if (verts.empty ())
  {
     pcl::console::print_error ("[addPolygonMesh] No vertices given!\n");
     return (false);
  }
 
  // Check to see if this ID entry already exists (has it been already added to the visualizer?)
  auto am_it = cloud_actor_map_->find (id);
  if (am_it == cloud_actor_map_->end ())
    return (false);
 
  // Get the current poly data
  vtkSmartPointer<vtkPolyData> polydata = dynamic_cast<vtkPolyData*>(am_it->second.actor->GetMapper ()->GetInput ());
  if (!polydata)
    return (false);
  vtkSmartPointer<vtkCellArray> cells = polydata->GetPolys ();
  if (!cells)
    return (false);
  vtkSmartPointer<vtkPoints> points   = polydata->GetPoints ();
  // Copy the new point array in
  vtkIdType nr_points = cloud->size ();
  points->SetNumberOfPoints (nr_points);
 
  // Get a pointer to the beginning of the data array
  float *data = (dynamic_cast<vtkFloatArray*> (points->GetData ()))->GetPointer (0);
 
  int ptr = 0;
  std::vector<int> lookup;
  // If the dataset is dense (no NaNs)
  if (cloud->is_dense)
  {
    for (vtkIdType i = 0; i < nr_points; ++i, ptr += 3)
      std::copy (&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
  }
  else
  {
    lookup.resize (nr_points);
    vtkIdType j = 0;    // true point index
    for (vtkIdType i = 0; i < nr_points; ++i)
    {
      // Check if the point is invalid
      if (!isFinite ((*cloud)[i]))
        continue;
 
      lookup [i] = static_cast<int> (j);
      std::copy (&(*cloud)[i].x, &(*cloud)[i].x + 3, &data[ptr]);
      j++;
      ptr += 3;
    }
    nr_points = j;
    points->SetNumberOfPoints (nr_points);
  }
 
  // Update colors
  vtkUnsignedCharArray* colors = vtkUnsignedCharArray::SafeDownCast (polydata->GetPointData ()->GetScalars ());
  if (!colors)
    return (false);
  int rgb_idx = -1;
  std::vector<pcl::PCLPointField> fields;
  rgb_idx = pcl::getFieldIndex<PointT> ("rgb", fields);
  if (rgb_idx == -1)
    rgb_idx = pcl::getFieldIndex<PointT> ("rgba", fields);
  if (rgb_idx != -1 && colors)
  {
    int j = 0;
    std::uint32_t offset = fields[rgb_idx].offset;
    for (std::size_t i = 0; i < cloud->size (); ++i)
    {
      if (!isFinite ((*cloud)[i]))
        continue;
      const auto* const rgb_data = reinterpret_cast<const pcl::RGB*>(reinterpret_cast<const char*> (&(*cloud)[i]) + offset);
      unsigned char color[3];
      color[0] = rgb_data->r;
      color[1] = rgb_data->g;
      color[2] = rgb_data->b;
      colors->SetTupleValue (j++, color);
    }
  }
 
  // Get the maximum size of a polygon
  int max_size_of_polygon = -1;
  for (const auto &vertex : verts)
    if (max_size_of_polygon < static_cast<int> (vertex.vertices.size ()))
      max_size_of_polygon = static_cast<int> (vertex.vertices.size ());
 
  // Update the cells
  cells = vtkSmartPointer<vtkCellArray>::New ();
  
  const auto idx = details::fillCells(lookup, verts, cells, max_size_of_polygon);
 
  cells->GetData ()->SetNumberOfValues (idx);
  cells->Squeeze ();
  // Set the the vertices
  polydata->SetPolys (cells);
 
  return (true);
}
 
#ifdef vtkGenericDataArray_h
#undef SetTupleValue
#undef InsertNextTupleValue
#undef GetTupleValue
#endif
 
#endif