PointClouds as service vs topic
In my system, I'm getting PointClouds from a sensor, and I have some nodes that need all of the point clouds (so they subscribe to a point cloud topic), but I have some nodes that only need to see the most recent point cloud every once in a while (once per minute, or so).
It seems wasteful to have those nodes subscribe to the point cloud topic as well, as I suppose that would result in copying a lot of data, even if most of it is thrown away; even if all nodes run on the same computer.
So what I'm planning to do is to have the sensor node that communicates with the sensor provide point clouds both as a topic (for streaming access) and as a service (so that interested nodes can request a scan here and there).
Does that look like a sensible solution?