How to convert (ROS) "geometry_msgs/Point" to sensor_msgs/PointCloud2?

I'm a student studying LIDAR algorithm. I have a LIDAR code that subscribes to sensor_msgs/PointCloud2. and I'm receiving geometry_msgs/Point data now. I wanna convert geometry_msgs/Point to sensor_msgs/PointCloud2. And I wanna apply the code I wrote. Please tell me the sensor_msgs::PointCloud2 type function in c++ !! And there are width and height, and so on in sensor_msgs/PointCloud2. How do I convert it? I'm curious because geometry_msgs/Point doesn't have them.

If it's sensor_msgs/LaserScan, I've converted it, but I'm not sure about geometry_msgs/Point.

Solution

I think the easiest way is to create a sensor_msgs::PointCloud, which contains a vector of geometry_msgs::Point32.

Then add your points to this msg and you call the method convertPointCloudToPointCloud2from point_cloud_conversion.hpp

static inline bool convertPointCloudToPointCloud2(
  const sensor_msgs::msg::PointCloud & input,
  sensor_msgs::msg::PointCloud2 & output)

to get the sensor_msgs::PointCloud2

or you could try creating a pcl::PointCloud2 and then convert using either the method fromPCL or moveFromPCL from pcl_conversions