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✓ ANSWER ACCEPTED

My npc's pathfinding is super laggy and the npc stops every once and a while, does anyone know why?

I went along with a tutorial for a pathfinding npc on youtube and changed it around so it fits my npc, and the pathfinding is super laggy and I don't know why.

local myHuman = script.Parent:WaitForChild("Humanoid")
local myRoot = script.Parent:WaitForChild("HumanoidRootPart")
local head = script.Parent:WaitForChild("Head")
local lowerTorso = script.Parent:WaitForChild("LowerTorso")
local grab = script.Parent:WaitForChild("grabanim")
local grabAnim = script.Parent.Humanoid:LoadAnimation(grab)
grabAnim.Priority = Enum.AnimationPriority.Action



local clone = script.Parent:Clone()

function walkRandomly()
	local xRand = math.random(-50,50)
	local zRand = math.random(-50,50)
	local goal = myRoot.Position + Vector3.new(xRand,0,zRand)
	
	local path = game:GetService("PathfindingService"):CreatePath()
	path:ComputeAsync(myRoot.Position, goal)
	local waypoints = path:GetWaypoints()
	
	if path.Status == Enum.PathStatus.Success then
		for _, waypoint in ipairs(waypoints) do
			if waypoint.Action == Enum.PathWaypointAction.Jump then
				myHuman.Jump = true
			end
			myHuman:MoveTo(waypoint.Position)
			local timeOut = myHuman.MoveToFinished:Wait(0.1)
			if not timeOut then
				print("Got stuck")
				myHuman.Jump = true
				walkRandomly()
			end
		end
	else
		print("Path failed")
		wait(0.1)
		walkRandomly()
	end
end

function findPath(target)
	local path = game:GetService("PathfindingService"):CreatePath()
	path:ComputeAsync(myRoot.Position,target.Position)
	local waypoints = path:GetWaypoints()
	
	if path.Status == Enum.PathStatus.Success then
		for _, waypoint in ipairs(waypoints) do
			if waypoint.Action == Enum.PathWaypointAction.Jump then
				myHuman.Jump = true
			end
			myHuman:MoveTo(waypoint.Position)
			local timeOut = myHuman.MoveToFinished:Wait(0.1)
			if not timeOut then
				myHuman.Jump = true
				print("Path too long!")
				findPath(target)
				break
			end
			if checkSight(target) then
				repeat
					print("Moving directly to the target")
					myHuman:MoveTo(target.Position)
					attack(target)
					wait(0.1)
					if target == nil then
						break
					elseif target.Parent == nil then
						break
					end
				until checkSight(target) == false or myHuman.Health < 1 or target.Parent.Humanoid.Health < 1
				break
			end
			if (myRoot.Position - waypoints[1].Position).magnitude > 20 then
				print("Target has moved, generating new path")
				findPath(target)
				break
			end
		end
	end
end

function checkSight(target)
	local ray = Ray.new(myRoot.Position, (target.Position - myRoot.Position).Unit * 40)
	local hit,position = workspace:FindPartOnRayWithIgnoreList(ray, {script.Parent})
	if hit then
		if hit:IsDescendantOf(target.Parent) and math.abs(hit.Position.Y - myRoot.Position.Y) < 3 then
			print("I can see the target")
			return true
		end
	end
	return false
end

function findTarget()
	local dist = 200
	local target = nil
	local potentialTargets = {}
	local seeTargets = {}
	for i,v in ipairs(workspace:GetChildren()) do
		local human = v:FindFirstChild("Humanoid")
		local torso = v:FindFirstChild("Torso") or v:FindFirstChild("HumanoidRootPart")
		if human and torso and v.Name ~= script.Parent.Name then
			if (myRoot.Position - torso.Position).magnitude < dist and human.Health > 0 then
				table.insert(potentialTargets,torso)
			end
		end
	end
	if #potentialTargets > 0 then
		for i,v in ipairs(potentialTargets) do
			if checkSight(v) then
				table.insert(seeTargets, v)
			elseif #seeTargets == 0 and (myRoot.Position - v.Position).magnitude < dist then
				target = v
				dist = (myRoot.Position - v.Position).magnitude
			end
		end
	end
	if #seeTargets > 0 then
		dist = 200
		for i,v in ipairs(seeTargets) do
			if (myRoot.Position - v.Position).magnitude < dist then
				target = v
				dist = (myRoot.Position - v.Position).magnitude
			end
		end
	end
	if target then
		end
	return target
end

function attack(target)
    if (myRoot.Position - target.Position).magnitude < 5 then
        grabAnim:Play()
        if target.Parent ~= nil then
            target.Parent.Humanoid:TakeDamage(20)
        end
        wait(.5)
    end
end

function died()
	wait(5)
	clone.Parent = workspace
	game:GetService("Debris"):AddItem(script.Parent,0.1)
end

myHuman.Died:Connect(died)

lowerTorso.Touched:Connect(function(obj)
	if not obj.Parent:FindFirstChild("Humanoid") then
		myHuman.Jump = true
	end
end)

function main()
	local target = findTarget()
	if target then
		myHuman.WalkSpeed = 18
		findPath(target)
	else
		myHuman.WalkSpeed = 8
		walkRandomly()
	end
end

while wait(0.1) do
	if myHuman.Health < 1 then
		break
	end
	main()
end

1 answer

✓ Accepted answer

#Network Ownership

In a Roblox game, all non-anchored parts are “physically simulated” — they can fall, bounce, float in water, etc. All of these things are handled automatically by Roblox so you don’t have to write your own physics engine.

When a Roblox game runs, several computers/devices are involved. To divide the work of calculating physics, Roblox automatically assigns parts to either the server or to a client. In general, if a part is near an in-game character, its physics will be calculated by that player’s device; otherwise it will be calculated by the server. In either case, the server or client that calculates a part’s physics is called its owner.

Since physics updates must be sent over the network, there’s a small delay between when the owner makes the physical changes and when the other devices see those changes. Normally this delay isn’t too noticeable, but issues may occur when part ownership changes.

#Example: Projectiles

Imagine a player is shooting an object at another player.

Problem

As the object travels through the air, it will get far from the shooter and ownership will switch to the server. Once the object gets close enough to the target player, it will switch ownership to the player. Even with a good network connection, there may be a tiny delay and visible “hop” when the object’s owner switches.

Solution

Manually set ownership of the projectile to the server using SetNetworkOwner(). This ensures that the owner does not change, preventing visible “hops.”

SetNetworkOwner() and its partner function GetNetworkOwner() must be set on the server side. Clients are not allowed to change ownership settings in a LocalScript.

#Your script

In your script, the NPC networks owner is changing from client to server, which will make it stutter a few times, delaying it's time to get to the destination.

We can use :SetNetworkOwner, to prevent it from stuttering. Put this at the top of your script

if script.Parent.HumanoidRootPart:CanSetNetworkOwnership() then
	script.Parent.HumanoidRootPart:SetNetworkOwner(nil) -- setting the owner to the server
end

2 comments

0

i did some tests with this and from what i saw all the issues are fixed, thanks!

0

No problem!

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