Parameter "robot radius" isn't used

[AndyKong2020]

Source code:src/ipa_coverage_planning/ipa_room_exploration/ros/src/room_exploration_action_server.cpp, src/ipa_coverage_planning/ipa_room_exploration/common/src/boustrophedon_explorator.cpp.
When I was to add an A* planner between each cells #38 in src/ipa_coverage_planning/ipa_room_exploration/common/src/boustrophedon_explorator.cpp , I tried to pass in the argument "robot radius" . Then I found that the only usage of the parameter is

   const float robot_radius = goal->robot_radius;
   const int robot_radius_in_pixel = (robot_radius / map_resolution);
   std::cout << "robot radius: " << robot_radius << " m   (" << robot_radius_in_pixel << " px)" << std::endl;

in src/ipa_coverage_planning/ipa_room_exploration/ros/src/room_exploration_action_server.cpp.
I commented out those lines, the project runs unaffected.
Is "robot radius" never used in all pllanners? Or there's other usages I didn't find?
#27

[AndyKong2020]

I tried to pass in half_grid_spacing_as_int*map_resolution as robot radius

a_star_path_planner.planPath(room_map, fov_middlepoint_path.back(), fov_middlepoint_path_part.front(), 1.0, half_grid_spacing_as_int*map_resolution, map_resolution, 0,
                              &astar_panned_path_part);

actually half_grid_spacing_as_int*map_resolution is related to tool radius