Hello, community :

   I have looked through the document about navigation .when I attempted to find all navigation's packages relationship ,I can't get through  the relation between costmap2d and base_local_planner .I just know both nva_core::BaseGlobalPlanner and nva_core::LocalPlanner need costmap ,But base_lcoal_planner do not subscribe any topic pubilshed by costmap2d.

Does anyone know ?

thanks everyone