pointcloud to laserscan with transform?

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With the help of others I have developed a nodelet to display a horizonal projection of a laserscan with a pan/tilt Kinect camera. This nodelet is intended to work with the other pointcloud_to_laserscan nodelets, providing a choice of two laserscan projection types. Here is the source code with detailed instructions appended at the end ...

SOURCE cloud_to_scanHoriz.cpp: /*
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#include "ros/ros.h"
#include "pluginlib/class_list_macros.h"
#include "nodelet/nodelet.h"
#include "sensor_msgs/LaserScan.h"
#include "pcl/point_cloud.h"
#include "pcl_ros/point_cloud.h"
#include "pcl/point_types.h"
#include "pcl/ros/conversions.h"
#include "pcl_ros/transforms.h"
#include "tf/transform_listener.h"
#include "tf/message_filter.h"
#include "message_filters/subscriber.h"


namespace pointcloud_to_laserscan
{
typedef pcl::PointCloud<pcl::PointXYZ> PointCloud;

class CloudToScanHoriz : public nodelet::Nodelet
{
public:
  //Constructor
  CloudToScanHoriz(): min_height_(0.10), max_height_(0.75), baseFrame("/base_footprint"), laserFrame("/camera_tower")
  {
  };

private:
  double min_height_, max_height_;
  std::string baseFrame;  //ground plane referenced by laser
  std::string laserFrame; //pan frame simulating projected laser
  bool result;

  tf::TransformListener tfListener;
  message_filters::Subscriber<PointCloud> cloudSubscriber;
  tf::MessageFilter<PointCloud> *tfFilter;

  ros::Publisher laserPublisher;

  //Nodelet initialization
  virtual void onInit()
  {
    ros::NodeHandle& nh = getNodeHandle();
    ros::NodeHandle& private_nh = getPrivateNodeHandle();

    private_nh.getParam("min_height", min_height_);
    private_nh.getParam("max_height", max_height_);
    private_nh.getParam("base_frame", baseFrame);
    private_nh.getParam("laser_frame", laserFrame);
    NODELET_INFO("CloudToScanHoriz min_height: %f, max_height: %f", min_height_, max_height_);
    NODELET_INFO("CloudToScanHoriz baseFrame: %s, laserFrame: %s", baseFrame.c_str(), laserFrame.c_str());

    //Set up to process new pointCloud and tf data together
    cloudSubscriber.subscribe(nh, "cloud_in", 5);
    tfFilter = new tf::MessageFilter<PointCloud>(cloudSubscriber, tfListener, laserFrame, 1);
    tfFilter->registerCallback(boost::bind(&CloudToScanHoriz::callback, this, _1));
    tfFilter->setTolerance(ros::Duration(0.01));

    laserPublisher = nh.advertise<sensor_msgs::LaserScan>("laserScanHoriz", 10);
  };

  //Pointcloud and tf transform received
  void callback(const PointCloud::ConstPtr& cloud_in)
  {
    PointCloud cloudTransformed;
    sensor_msgs::LaserScanPtr ...