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

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4 years ago

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.

001local myHuman = script.Parent:WaitForChild("Humanoid")
002local myRoot = script.Parent:WaitForChild("HumanoidRootPart")
003local head = script.Parent:WaitForChild("Head")
004local lowerTorso = script.Parent:WaitForChild("LowerTorso")
005local grab = script.Parent:WaitForChild("grabanim")
006local grabAnim = script.Parent.Humanoid:LoadAnimation(grab)
007grabAnim.Priority = Enum.AnimationPriority.Action
008 
009 
010 
011local clone = script.Parent:Clone()
012 
013function walkRandomly()
014    local xRand = math.random(-50,50)
015    local zRand = math.random(-50,50)
016    local goal = myRoot.Position + Vector3.new(xRand,0,zRand)
017 
018    local path = game:GetService("PathfindingService"):CreatePath()
019    path:ComputeAsync(myRoot.Position, goal)
020    local waypoints = path:GetWaypoints()
021 
022    if path.Status == Enum.PathStatus.Success then
023        for _, waypoint in ipairs(waypoints) do
024            if waypoint.Action == Enum.PathWaypointAction.Jump then
025                myHuman.Jump = true
026            end
027            myHuman:MoveTo(waypoint.Position)
028            local timeOut = myHuman.MoveToFinished:Wait(0.1)
029            if not timeOut then
030                print("Got stuck")
031                myHuman.Jump = true
032                walkRandomly()
033            end
034        end
035    else
036        print("Path failed")
037        wait(0.1)
038        walkRandomly()
039    end
040end
041 
042function findPath(target)
043    local path = game:GetService("PathfindingService"):CreatePath()
044    path:ComputeAsync(myRoot.Position,target.Position)
045    local waypoints = path:GetWaypoints()
046 
047    if path.Status == Enum.PathStatus.Success then
048        for _, waypoint in ipairs(waypoints) do
049            if waypoint.Action == Enum.PathWaypointAction.Jump then
050                myHuman.Jump = true
051            end
052            myHuman:MoveTo(waypoint.Position)
053            local timeOut = myHuman.MoveToFinished:Wait(0.1)
054            if not timeOut then
055                myHuman.Jump = true
056                print("Path too long!")
057                findPath(target)
058                break
059            end
060            if checkSight(target) then
061                repeat
062                    print("Moving directly to the target")
063                    myHuman:MoveTo(target.Position)
064                    attack(target)
065                    wait(0.1)
066                    if target == nil then
067                        break
068                    elseif target.Parent == nil then
069                        break
070                    end
071                until checkSight(target) == false or myHuman.Health < 1 or target.Parent.Humanoid.Health < 1
072                break
073            end
074            if (myRoot.Position - waypoints[1].Position).magnitude > 20 then
075                print("Target has moved, generating new path")
076                findPath(target)
077                break
078            end
079        end
080    end
081end
082 
083function checkSight(target)
084    local ray = Ray.new(myRoot.Position, (target.Position - myRoot.Position).Unit * 40)
085    local hit,position = workspace:FindPartOnRayWithIgnoreList(ray, {script.Parent})
086    if hit then
087        if hit:IsDescendantOf(target.Parent) and math.abs(hit.Position.Y - myRoot.Position.Y) < 3 then
088            print("I can see the target")
089            return true
090        end
091    end
092    return false
093end
094 
095function findTarget()
096    local dist = 200
097    local target = nil
098    local potentialTargets = {}
099    local seeTargets = {}
100    for i,v in ipairs(workspace:GetChildren()) do
101        local human = v:FindFirstChild("Humanoid")
102        local torso = v:FindFirstChild("Torso") or v:FindFirstChild("HumanoidRootPart")
103        if human and torso and v.Name ~= script.Parent.Name then
104            if (myRoot.Position - torso.Position).magnitude < dist and human.Health > 0 then
105                table.insert(potentialTargets,torso)
106            end
107        end
108    end
109    if #potentialTargets > 0 then
110        for i,v in ipairs(potentialTargets) do
111            if checkSight(v) then
112                table.insert(seeTargets, v)
113            elseif #seeTargets == 0 and (myRoot.Position - v.Position).magnitude < dist then
114                target = v
115                dist = (myRoot.Position - v.Position).magnitude
116            end
117        end
118    end
119    if #seeTargets > 0 then
120        dist = 200
121        for i,v in ipairs(seeTargets) do
122            if (myRoot.Position - v.Position).magnitude < dist then
123                target = v
124                dist = (myRoot.Position - v.Position).magnitude
125            end
126        end
127    end
128    if target then
129        end
130    return target
131end
132 
133function attack(target)
134    if (myRoot.Position - target.Position).magnitude < 5 then
135        grabAnim:Play()
136        if target.Parent ~= nil then
137            target.Parent.Humanoid:TakeDamage(20)
138        end
139        wait(.5)
140    end
141end
142 
143function died()
144    wait(5)
145    clone.Parent = workspace
146    game:GetService("Debris"):AddItem(script.Parent,0.1)
147end
148 
149myHuman.Died:Connect(died)
150 
151lowerTorso.Touched:Connect(function(obj)
152    if not obj.Parent:FindFirstChild("Humanoid") then
153        myHuman.Jump = true
154    end
155end)
156 
157function main()
158    local target = findTarget()
159    if target then
160        myHuman.WalkSpeed = 18
161        findPath(target)
162    else
163        myHuman.WalkSpeed = 8
164        walkRandomly()
165    end
166end
167 
168while wait(0.1) do
169    if myHuman.Health < 1 then
170        break
171    end
172    main()
173end
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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.

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

1if script.Parent.HumanoidRootPart:CanSetNetworkOwnership() then
2    script.Parent.HumanoidRootPart:SetNetworkOwner(nil) -- setting the owner to the server
3end

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

1 answer

Network Ownership

Example: Projectiles

Problem

Solution

Your script

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