Pathfinding can't detect blocked

Help and Feedback Scripting Support
#1

First sorry for my broken english. I’m trying to make a npc that goes selected destinations, everything works good but only problem is if the path is blocked first npc pass after that he can’t calculate the path and giving me error.

the error :

notwork.PNG
notwork.PNG1579×788 258 KB

Normally if i just do print(“path is blocked”) it can detect the path is blocked.

works.PNG
works.PNG1556×769 243 KB

I search the issue for 2 days and now I’m here.

Here is the code:

local hum = script.Parent
local humrp = script.Parent.Parent.HumanoidRootPart
local pathFindingService = game:GetService("PathfindingService")
local destinations = game.Workspace.Destinations

local path = pathFindingService:CreatePath()

local function getPath(destination)
	local path = pathFindingService:CreatePath()
	
	path:ComputeAsync(humrp.Position, destination.Position)
	
	return path
end

local function walkTo(destination)	
	local path = getPath(destination)
	
	path.Blocked:Connect(function(dest)
		print("path blocked")
		path = getPath((dest))
	end)
	
	for index, waypoint in pairs(path:GetWaypoints()) do
		hum:MoveTo(waypoint.Position)
		hum.MoveToFinished:Wait()
	end
end

while true do
	walkTo(destinations.dest1)
	walkTo(destinations.dest2)
	walkTo(destinations.dest3)
	walkTo(destinations.dest4)
	walkTo(destinations.dest5)
	walkTo(destinations.dest6)
end
#2

The error indicates that the object you are trying to get the position of is nil, so it either does not exist or was not assigned properly.

In your case, it means that dest is nil, so make sure that path.Blocked is returning a valid waypoint.

	path.Blocked:Connect(function(dest)
		print("path blocked")
                   if dest ~= nil then
		     path = getPath((dest))
                    else
                      ----- find something to do if dest is nil, maybe a failsafe stop
                 end
	end)

YOU ALSO CAN

Make it re-calculate path when it detects that it is blocked

local function walkTo(destination)	
	local path = getPath(destination)

	path.Blocked:Connect(function(dest)
		print("path blocked")
		path:ComputeAsync(humrp.Position, destination) ---- re-calculate path no need to re-assign path
		if path.Status == Enum.PathStatus.Succeess then
			-- Retrieve update waypoint list with path:GetWaypoints()
			-- and Continue walking towards target
			
			--- you can try re-using MoveTo  with the re-computed path here
		else
			-- Error, path not found
		end
	end)

	for index, waypoint in pairs(path:GetWaypoints()) do
		hum:MoveTo(waypoint.Position)
		hum.MoveToFinished:Wait()
	end
end

I am unsure if that properly solves your issue since i haven’t used pathfinding too much.
But this should atleast help you understand what the error is.

1 Like
#3

thx for reply it’s still not works, i just changed script to make collision false