Best way to add self-generated waypoints to FlightDisplayMap

Hi, I am very new to Drone and QT, had been trying to modify QGC to suit my projects needs.

Currently, I have a program that will generate a series of waypoint given a source and destination, I hope to draw these waypoints onto the PlanView.qml FlightDisplayMap; any suggestions on where I should start to look into?

I have also tried to trace the draw waypoint function to visualItemsChanged signal in MissionController.h, however, I fail to find the corresponding slot that do the drawings, is there anyway I can find the designated slot ?

Any suggestions would be welcome~ Thanks~