Include frontier_detector.h header in your file:
#include "frontier_detector.h"
Dynamically create a frontier detector object:
frontier_detector = std::make_shared<WavefrontFrontierDetector>();
Create a vector to hold the detected frontier segements:
std::vector<FrontierSegment> frontier_segments;
Search for the frontiers:
frontier_detector->searchFrontierSegments(frontier_segments,current_robot_pose,costmap);
You can access the centroid of the detected frontier segments i by:
geometry_msgs::msg::Point centroid = frontier_segments[i].centroid;