How can I get closest point in navmesh from point out of navmesh

Hi. I made AI but when target jump or out of navmesh. AI moved forward forever. I found some functions that ProjectPointToNavigation, GetRandomReachablePointInRadius, GetRandomPointInNavigableRadius. But I can’t under stand that functions usage and how to run. even ProjectPointToNavigation not work. I want to get closest point in navemesh from point out of mesh.
also is there function that check point in navmesh? last there is few navigation system information. Where can I find useful information about ue4 navigation system. I can’t understand how can I use navigation system in C++.

would love to see an answer for this!

I found there are two navigation in unreal, RecastNavmeshData and AbstractNavmeshData. RecastNavmeshData that is we find. AbstractNavmeshData is special navmesh data. That give direction and other I found in document. You can find navmesh tile using NavigationSystem’s RecastNavmeshData. I find unreal navmesh find navmesh tile using box. You can see extenstion params in RecastNavmeshData’s ProjectPointToNavmesh. Extension meaning is box’s scale. So if you extend extenstion’s param x, y you can find closest navmesh tile and you can get location.