NPC fails to NavigateTo after Teleport in Verse – inconsistent AI behavior

General Issues and Bug Reporting
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1

Summary

I am using NavigateTo with an agent as the target, to make an NPC follow the player.
If the return value of NavigateTo is Interrupted, I stop the follow behavior and teleport the NPC near the player using TeleportTo.

However, in this case, the NPC unexpectedly returns to the position it was in before the teleport, even though no new NavigateTo call has been made.

This issue still occurs even if I insert a Sleep(1.0) after detecting Interrupted and before teleporting the NPC.

Please select what you are reporting on:

Verse

What Type of Bug are you experiencing?

AI

Steps to Reproduce

  1. Make an NPC follow a player using NavigateTo.
  2. Check the navigation result.
  3. If the result is not Reached, especially if it is Interrupted, teleport the NPC using TeleportTo.

Code snippet:

NavTarget := MakeNavigationTarget(PlayerAgent)
NavigationResult := PetNavigatable.NavigateTo(NavTarget, ?ReachRadius := 110.0, ?AllowPartialPath := false)

if (NavigationResult = navigation_result.Reached):
    Print("Reached")
else if:
    NavigationResult = navigation_result.PartiallyReached or
    NavigationResult = navigation_result.Blocked or
    NavigationResult = navigation_result.Unreachable or
    NavigationResult = navigation_result.Interrupted
then:
    if (NPCCharacter.TeleportTo[Position, Rotation])

Expected Result

Since NavigateTo has finished (with a non-success result), the NPC should remain in place after being teleported.

Observed Result

The NPC begins moving toward the position it was in before the teleport, even though NavigateTo was not called again.

Platform(s)

PC (Windows 11)
UEFN (Unreal Editor for Fortnite)

Video

Additional Notes

  • This issue occurs roughly 50% of the time.
  • It rarely happens on flat, empty terrain.
  • It is more likely to happen when there are props or complex level geometry near the teleport location.
  • This suggests that the NavMesh or movement state may be disrupted by overlapping props or collision.
3

FORT-914617 has been added to our ‘To Do’ list. Someone’s been assigned this task.

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