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COMMUNITY QUESTION

[SOLVED] Why does the Monster AI doesn't chase when a player is near?

Asked 198 views1 answers

I am making the AI for the monster in my horror maze game. It works fine, but it follows the waypoint instead of chasing me when I get close. And the AI keeps bumping into walls when they can choose a longer way to get to that waypoint without bumping in walls.

Here is the video recording, the photo of all waypoints in the maze, and the AI Script:

local PathfindingService = game:GetService("PathfindingService")
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local monster = script.Parent
local monsterHumanoid = monster:WaitForChild("Humanoid")
local monsterWaypoints = workspace:WaitForChild("MonsterWaypoints")
local monsterRoot = monster:WaitForChild("HumanoidRootPart")

for index, bodyPart in pairs(monster:GetDescendants()) do
	if bodyPart:IsA("BasePart") then
		bodyPart:SetNetworkOwner(nil)
	end
end

local function CheckIfAlive(character)
	if ((character ~= nil) and (Players:GetPlayerFromCharacter(character) ~= nil) and (character:FindFirstChild("Head") ~= nil) and (character:FindFirstChild("HumanoidRootPart") ~= nil) and (character:FindFirstChildOfClass("Humanoid") ~= nil) and ((character:FindFirstChildOfClass("Humanoid")).Health > 0)) then
		return true
	end
end

local function CanSeeTarget(target)
	local origin = monsterRoot.Position
	local direction = (target:WaitForChild("HumanoidRootPart").Position - monsterRoot.Position).Unit * 40
	local ray = Ray.new(origin, direction)
	
	local hit, pos = workspace:FindPartOnRay(ray, monster)
	
	if (hit ~= nil) then
		if hit:IsDescendantOf(target) then
			return true
		end
	else
		return false
	end
end

local function FindTarget()
	local maxDistance = 40
	local nearestTarget
	
	for index, player in pairs(Players:GetPlayers()) do
		local character = player.Character or player.CharacterAdded:Wait()
		
		if (character ~= nil) then
			local target = character
			local distance = (monsterRoot.Position - character:WaitForChild("HumanoidRootPart").Position).Magnitude
			
			if (distance < maxDistance) and (CanSeeTarget(target) == true) then
				nearestTarget = target
				maxDistance = distance
			end
		end
	end
	
	return nearestTarget
end

local function GetPath(destination)
	local agentParameters = {
		["AgentHeight"] = 5,
		["AgentRadius"] = 4,
		["AgentCanJump"] = false,
		["Costs"] = {
			["SafeSpot"] = math.huge
		}
	}
	
	local path = PathfindingService:CreatePath(agentParameters) 
	path:ComputeAsync(monsterRoot.Position, destination.Position)
	
	return path
end

function Attack(target)
	local distance = (monsterRoot.Position - target:WaitForChild("HumanoidRootPart").Position).Magnitude
	
	if distance > 4 then
		monsterHumanoid:MoveTo(target:WaitForChild("HumanoidRootPart").Position)
	else
		target:FindFirstChildOfClass("Humanoid"):TakeDamage(target:FindFirstChildOfClass("Humanoid").MaxHealth)
	end
end

function WalkTo(destination)
	local path = GetPath(destination)
	
	if path.Status == Enum.PathStatus.Success then
		for index, waypoint in pairs(path:GetWaypoints()) do
			local target = FindTarget()
			
			if (target ~= nil) and (CheckIfAlive(target) == true) then
				Attack(target)
				break
			else
				monsterHumanoid:MoveTo(waypoint.Position)
				monsterHumanoid.MoveToFinished:Wait()
			end
		end
	else
		monsterHumanoid:MoveTo((destination.Position - (monsterRoot.CFrame.LookVector * 10)))
	end
end

function Patrol()
	local waypoints = monsterWaypoints:GetChildren()
	local randomWaypoint = waypoints[math.random(1, #waypoints)]
	WalkTo(randomWaypoint)
end

while true do
	task.wait()
	Patrol()
end
AnonymousEdited

6 comments

0

Check in the script if you haven't set something that makes the AI moving to the waypoint.

Anonymous#
0

I literally checked everything in the script and everything’s fine. That’s why I’m asking for help. If I had knew already I would’ve not created this question in the first place.

Anonymous#
0

you might want to disable the function patrol when pathfinding to the player

Anonymous#
0

the patrol function should be activated when Target == nil so it does not interfere with the pathfinding to the target

Anonymous#
0

ok thx i’ll try that

Anonymous#
0

puppynniko thx for the help, it worked :)

Anonymous#

1 answer

I finally fixed it! @Puppynniko suggested detecting if the target is nill or not in the patrol function, and it worked! Thanks to @Puppynniko! This is my new AI script:

local PathfindingService = game:GetService("PathfindingService")
local Players = game:GetService("Players")
local ReplicatedStorage = game:GetService("ReplicatedStorage")

local monster = script.Parent
local monsterHumanoid = monster:WaitForChild("Humanoid")
local monsterWaypoints = workspace:WaitForChild("MonsterWaypoints")
local monsterRoot = monster:WaitForChild("HumanoidRootPart")

local chasing = false
local hipHeight = monsterHumanoid.HipHeight
local HitboxLength = 4

local agentParameters = {
	["AgentHeight"] = ((hipHeight > 0 and hipHeight) or 5),
	["AgentRadius"] = (monsterRoot.Size.X or 2),
	["AgentCanJump"] = false,
	["Costs"] = {
		["SafeSpot"] = math.huge
	}
}

for index, bodyPart in pairs(monster:GetDescendants()) do
	if bodyPart:IsA("BasePart") or bodyPart:IsA("MeshPart") or bodyPart:IsA("UnionOperation") then
		bodyPart:SetNetworkOwner(nil)
	end
end

local function CheckIfAlive(character)
	if ((character ~= nil) and (Players:GetPlayerFromCharacter(character) ~= nil) and (character:FindFirstChild("Head") ~= nil) and (character:FindFirstChild("HumanoidRootPart") ~= nil) and (character:FindFirstChildOfClass("Humanoid") ~= nil) and ((character:FindFirstChildOfClass("Humanoid")).Health > 0)) then
		return true
	else
		return false
	end
end

local function CheckIfTargetIsSafe(target)
	if (target ~= nil) and (Players:GetPlayerFromCharacter(target) ~= nil) and (target:FindFirstChild("Head") ~= nil) and (target:FindFirstChild("HumanoidRootPart") ~= nil) and (target:FindFirstChildOfClass("Humanoid") ~= nil) then
		if Players:GetPlayerFromCharacter(target):FindFirstChild("Safe") then
			if Players:GetPlayerFromCharacter(target):FindFirstChild("Safe").Value == true then
				return true
			else
				if target:FindFirstChildOfClass("ForceField") then
					return true
				else
					return false
				end
			end
		else
			if target:FindFirstChildOfClass("ForceField") then
				return true
			else
				return false
			end
		end
	else
		return false
	end
end

local function CanSeeTarget(target)
	local origin = monsterRoot.Position
	local direction = (target:WaitForChild("HumanoidRootPart").Position - monsterRoot.Position).Unit * 1000
	local ray = Ray.new(origin, direction)
	
	local hit, pos = workspace:FindPartOnRayWithIgnoreList(ray, {monster})
	
	if hit then
		if hit:IsDescendantOf(target) then
			if target:FindFirstChildOfClass("ForceField") then
				return true
			else
				local plr = Players:GetPlayerFromCharacter(target)
				
				if plr then
					local safeValue = plr:FindFirstChild("Safe")
					
					if safeValue then
						if safeValue.Value == false then
							return true
						else
							return false
						end
					else
						return false
					end
				else
					return false
				end
			end
		end
	else
		return false
	end
end

local function FindTarget()
	local maxDistance = 10000
	local nearestTarget
	
	for index, player in pairs(Players:GetPlayers()) do
		local character = player.Character or player.CharacterAdded:Wait()
		
		if character then
			local target = character
			local distance = (monsterRoot.Position - character:WaitForChild("HumanoidRootPart").Position).Magnitude
			
			if (distance < maxDistance) and (CanSeeTarget(target) == true) then
				nearestTarget = target
				maxDistance = distance
			end
		end
	end
	
	return nearestTarget
end

local function GetPath(destination)
	local path = PathfindingService:CreatePath(agentParameters) 
	path:ComputeAsync(monsterRoot.Position, destination.Position)
	
	return path
end

function Attack(target)
	local distance = (monsterRoot.Position - target:WaitForChild("HumanoidRootPart").Position).Magnitude
	
	if distance > (HitboxLength or 1) then
		monsterHumanoid:MoveTo(target:WaitForChild("HumanoidRootPart").Position)
	else
		target:FindFirstChildOfClass("Humanoid"):TakeDamage(target:FindFirstChildOfClass("Humanoid").MaxHealth)
	end
end

function WalkTo(destination)
	local path = GetPath(destination)
	
	if path.Status == Enum.PathStatus.Success then
		for index, waypoint in pairs(path:GetWaypoints()) do
			local target = FindTarget()
			
			if target and CanSeeTarget(target) and (CheckIfAlive(target) == true) and (CheckIfTargetIsSafe(target) == false) then
				break
			else
				monsterHumanoid:MoveTo(waypoint.Position)
				monsterHumanoid.MoveToFinished:Wait()
			end
		end
	else
		monsterHumanoid:MoveTo((destination.Position - (monsterRoot.CFrame.LookVector * 10)))
	end
end

function Patrol()
	local target = FindTarget()
	
	if target and CanSeeTarget(target) and (CheckIfAlive(target) == true) and (CheckIfTargetIsSafe(target) == false) then
		Attack(target)
	else
		local waypoints = monsterWaypoints:GetChildren()
		local randomWaypoint = waypoints[math.random(1, #waypoints)]
		WalkTo(randomWaypoint)
	end
end

while true do
	task.wait()
	Patrol()
end

Also, you can use this script too to make your own Monster AI! Don't exactly copy-paste mine because it could cause errors.

If you're wondering what game it is, here's the game!

AnonymousEdited Permalink

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