NPC not following nearest player

Help and Feedback Scripting Support
#1

Hi there, I’m currently making an NPC that follows the nearest players. (Have no experiences in AIs, pardon me for any mistakes in the code). Basically the current code I have is very simple, you can have a look at it here:
AIClass:

local AIClass = {}
AIClass.__index = AIClass


local pathFinding = require(script.PathFinding)

function AIClass.init(AI, range)
	local self = setmetatable({}, AIClass)
	
	self.Target = nil
	self.distToTarget = range
	self.detectionRange = range
	self.AI = AI

	self.detectionBox = pathFinding:CreateDetection(self.AI, self.detectionRange)
	
	return self
end

function AIClass:findTarget()
	local getParts = workspace:FindPartsInRegion3WithIgnoreList(self.detectionBox, {self.AI})
	
	for _, v in pairs(getParts) do
		if v.Parent:FindFirstChild("Humanoid") then
			if self.Target ~= v.Parent and self.Target ~= nil then
				if (self.AI.HumanoidRootPart.Position - v.Parent.HumanoidRootPart.Position).Magnitude < (self.Target.HumanoidRootPart.Position - v.Parent.HumanoidRootPart.Position).Magnitude then
					pathFinding:ComputePath(self.AI, v.Parent.HumanoidRootPart.Position)
				end
			else
				pathFinding:ComputePath(self.AI, v.Parent.HumanoidRootPart.Position)
			end
			
			self.Target = v.Parent
			self.distToTarget = (self.AI.HumanoidRootPart.Position - self.Target.HumanoidRootPart.Position).Magnitude
		end
	end
	
	return self.Target
end

return AIClass

Path finding module:

local PathFinding = {}

local PathFindingService = game:GetService("PathfindingService")

local region

function PathFinding:CreateDetection(AI, size)
	-- create part with all the infos blah blah blah
	region = Region3.new(part.Position - (0.5 * part.Size), part.Position + (0.5 * part.Size))

	return region
end

function PathFinding:ComputePath(AI, destination)
	local AIHead = AI.Head
	local AIHum = AI.Humanoid
	local AIHrp = AI.HumanoidRootPart

	local raycastParams = RaycastParams.new()
	raycastParams.FilterDescendantsInstances = {AI}
	raycastParams.FilterType = Enum.RaycastFilterType.Blacklist
	
	if AIHead then
		local hit = workspace:Raycast(AIHead.Position, (destination - AIHead.Position) * 100, raycastParams)

		if hit then
			if hit.Instance.Parent:FindFirstChild("Humanoid") then
				AIHum:MoveTo(destination)

			else
				local path = PathFindingService:CreatePath()
				path:ComputeAsync(AIHrp.Position, destination)
				
				if path.Status == Enum.PathStatus.Success then
					local points = path:GetWaypoints()
					for i, v in pairs(points) do
						AIHum:MoveTo(v.Position)

						if v.Action == Enum.PathWaypointAction.Jump then
							AIHum.Jump = true
						end
					end				
				else
					AIHum:MoveTo(destination)
				end
			end
		end
	end
end

return PathFinding

You can have a look at the issue here: https://gyazo.com/7462a870c6b5ce1fb6b7531568b33ac8
Even though it seems fine, some errors started to occur, it will follow a wrong player even though a player is already in front of them (You can have a look at the output for the current target) . I have tried adding a break / return whenever it finds a closer target than its’ current one, but it will break the code because the AI will now have 2 target to follow for whatever reason.
Any help is appreciated!
Edit: pls help i have no idea why it’s functioning like this

#2

Would you consider switching from a part to something more performant like a table or CollectionService for handling the characters that are available? Doing that would make this simpler, I think what’s happening is that your AI is iterating and finding the other character and calculating a path for it, which is asynchronous, which is why it keeps going back to 1.

You should make 3 changes:
1- make a table with the available characters’ models, this would clean up you looking for _.Parent.Humanoid and would avoid you iterating through the characters too many times.
2- use a loop to determine the closest humanoid before calculating a new path.
3- switch from a part and iterate through the characters using .Magnitude instead

I don’t know if that makes sense but:

local maxCharacterRadius = 25 -- let's say the character must be within 25 studs

-- ...

local characters = table.of.models

local smallestDistance, smallestDistanceCharacter = math.huge, nil -- these will be how we will navigate finding the closest character
for i,v in ipairs(characters) do
    local humanoidRootPart = v:FindFirstChild('HumanoidRootPart')
    if not humanoidRootPart then continue end -- character probably isn't valid
    local humanoid = v:FindFirstChild('Humanoid')
    local currentMagnitude = (AIHrp.Position - humanoidRootPart.Position).Magnitude
    if (currentMagnitude < smallestDistance) and (currentMagnitude < maxCharacterRadius) then -- if it's smaller than the current smallest distance and it's in range then
        smallestDistance, smallestDistanceCharacter = currentMagnitude, v
    end
end
if smallestDistanceCharacter then
    -- this is the smallest character, chase the new smallest character
else
    -- nobody's in range
end
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