OccupancyGrid and OccupancyGridUpdate: how to use them?

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Hi,

I have looked on the web to understand how to use them properly to my aim, without success. I guess OccupancyGridUpdate messages are used to update efficiently the costmap, with overwriting every time the whole map.

Now, I would like to have in the OccupancyGrid topic the updated costmap, is there a way to tell the move_base to do so in place of publishing the OccupancyGridUpdates? (I'm using TIAGo robot from PAL)

If not, how can I update the move_base local costmap in my C++ code using OccupancyGridUpdate and convert it to an OccupancyGrid message?

Thanks a lot.