Struggling with making a detection system for a stealth game

Help and Feedback Scripting Support
,
#21

Here you go. I’d personally recommend and while true do loop, but this should solve your problems. You’ll have to readd your remote event code, I did this quickly so I could test it. Realistic angles of fov, a bar using tween service to go up on down depending on detection, etc.

-- Get necessary services
local RunService = game:GetService("RunService")
local PlayersService = game:GetService("Players")
local TweenService = game:GetService("TweenService")

-- Set NPC and character, along with their sight and range properties
local npc = workspace.World.Debug.NPC.DetectionTest
local npcSight = 0.7
local npcRange = 100

-- GUI elements and reaction time
local player = PlayersService.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()
local head = character:WaitForChild("Head")

local playerGui = player.PlayerGui
local DetectionBar = playerGui:WaitForChild("DetectionGUI")
local reactionTime = 1.8

-- Create a table to hold TweenInfo
local tweenInfo = TweenInfo.new(
	2,  -- Time
	Enum.EasingStyle.Linear,  -- EasingStyle
	Enum.EasingDirection.Out,  -- EasingDirection
	0,  -- RepeatCount (0 implies the tween will not repeat)
	false,  -- Reverses (should the tween reverse once reaching the endpoint)
	0  -- DelayTime
)

local characterIsInFov = false

RunService.Heartbeat:Connect(function()
	if character and npc then -- Check if the character and the NPC are not null

		-- Calculate the vector between the NPC and the character
		local npcToCharacter = (head.Position - npc.Head.Position).Unit
		local npcLook = npc.Head.CFrame.LookVector
		local dotProduct = npcToCharacter:Dot(npcLook)

		if dotProduct > npcSight then
			--character is in field of view        
			characterIsInFov = true
		else
			-- character is not in field of view so we do not need to take any action
			characterIsInFov = false
		end

		-- Prepare parameters for raycasting
		local raycastParams = RaycastParams.new()
		raycastParams.FilterType = Enum.RaycastFilterType.Exclude
		raycastParams.FilterDescendantsInstances = {npc}
		raycastParams.IgnoreWater = true

		-- Perform a raycast to check if the character is in sight
		local ray = workspace:Raycast(npc.PrimaryPart.Position, (character.PrimaryPart.Position - npc.PrimaryPart.Position).Unit * npcRange, raycastParams)

		-- Check if the character is in range and in field of view
		if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
			if ray and ray.Instance.Parent == character then
				local hitPlayer = PlayersService:GetPlayerFromCharacter(ray.Instance.Parent)
				if hitPlayer then
					-- Animate the detection bar
					local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, math.clamp(dotProduct * 2, 0, 1), 0)})
					tween:Play()
					DetectionBar.detectionFrame.detectionBar.BackgroundColor3 = Color3.fromRGB(255, 0, 0)

					-- Wait for reaction time and check again
					task.wait(reactionTime)

					if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
						print('Player detected: ', hitPlayer.Name)
					end
				end
			else
				-- Decrease the detection bar when not in sight
				local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, 0, 0)})
				tween:Play()
			end
		else
			-- Decrease the detection bar when not in sight
			local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, 0, 0)})
			tween:Play()
		end
	end
end)
1 Like
#22

It doesn’t quite work as intended but we are REALLY close, I think just a little bit of tweaking or something and we might be alright

Here’s what happened:

1 Like
#23

Very close. Let me write up a possible fix…

Try this:

-- Get necessary services
local RunService = game:GetService("RunService")
local PlayersService = game:GetService("Players")
local TweenService = game:GetService("TweenService")

-- Set NPC and character, along with their sight and range properties
local npc = workspace.World.Debug.NPC.DetectionTest
local npcSight = 0.7
local npcRange = 100

-- GUI elements and reaction time
local player = PlayersService.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()
local head = character:WaitForChild("Head")

local playerGui = player.PlayerGui
local DetectionBar = playerGui:WaitForChild("DetectionGUI")
local reactionTime = 1.8

-- Create a table to hold TweenInfo
local tweenInfo = TweenInfo.new(
	1,  -- Time
	Enum.EasingStyle.Linear,  -- EasingStyle
	Enum.EasingDirection.Out,  -- EasingDirection
	0,  -- RepeatCount (0 implies the tween will not repeat)
	false,  -- Reverses (should the tween reverse once reaching the endpoint)
	0  -- DelayTime
)

local characterIsInFov = false
local detectionProgress = 0 -- Variable to keep track of detection progress

RunService.Heartbeat:Connect(function()
	if character and npc then -- Check if the character and the NPC are not null

		-- Calculate the vector between the NPC and the character
		local npcToCharacter = (head.Position - npc.Head.Position).Unit
		local npcLook = npc.Head.CFrame.LookVector
		local dotProduct = npcToCharacter:Dot(npcLook)

		if dotProduct > npcSight then
			--character is in field of view        
			characterIsInFov = true
		else
			-- character is not in field of view so we do not need to take any action
			characterIsInFov = false
		end

		-- Prepare parameters for raycasting
		local raycastParams = RaycastParams.new()
		raycastParams.FilterType = Enum.RaycastFilterType.Exclude
		raycastParams.FilterDescendantsInstances = {npc}
		raycastParams.IgnoreWater = true

		-- Perform a raycast to check if the character is in sight
		local ray = workspace:Raycast(npc.PrimaryPart.Position, (character.PrimaryPart.Position - npc.PrimaryPart.Position).Unit * npcRange, raycastParams)

		-- Check if the character is in range and in field of view
		if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
			if ray and ray.Instance.Parent == character then
				local hitPlayer = PlayersService:GetPlayerFromCharacter(ray.Instance.Parent)
				if hitPlayer then
					-- Increase the detection progress
					detectionProgress = math.min(detectionProgress + dotProduct * 2, 1)

					-- Animate the detection bar
					local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, detectionProgress, 0)})
					tween:Play()
					DetectionBar.detectionFrame.detectionBar.BackgroundColor3 = Color3.fromRGB(255, 0, 0)

					-- Check if the detection bar is filled completely before triggering the NPC detection
					if detectionProgress == 1 then
						-- Wait for reaction time and check again
						task.wait(reactionTime)
						if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
							print('Player detected: ', hitPlayer.Name)
						end
					end
				end
			else
				-- Decrease the detection bar when not in sight
				detectionProgress = math.max(detectionProgress - 0.05, 0) -- Decrease the detection progress
				local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, detectionProgress, 0)})
				tween:Play()
			end
		else
			-- Decrease the detection bar when not in sight
			detectionProgress = math.max(detectionProgress - 0.05, 0) -- Decrease the detection progress
			local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, detectionProgress, 0)})
			tween:Play()
		end
	end
end)
1 Like
#24

Detection part of it is excellent, just the bar that’s being a bit dodgy (going to have my tea now so I’ll be back in about 10 minutes or so :laughing:)

1 Like
#25 
-- Get necessary services
local RunService = game:GetService("RunService")
local PlayersService = game:GetService("Players")
local TweenService = game:GetService("TweenService")

-- Set NPC and character, along with their sight and range properties
local npc = workspace.World.Debug.NPC.DetectionTest
local npcSight = 0.7
local npcRange = 100

-- GUI elements and reaction time
local player = PlayersService.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()
local head = character:WaitForChild("Head")

local playerGui = player.PlayerGui
local DetectionBar = playerGui:WaitForChild("DetectionGUI")
local reactionTime = 1.8

-- Create a table to hold TweenInfo
local tweenInfo = TweenInfo.new(
	1.5,  -- Time
	Enum.EasingStyle.Quad,  -- EasingStyle
	Enum.EasingDirection.Out,  -- EasingDirection
	0,  -- RepeatCount (0 implies the tween will not repeat)
	false,  -- Reverses (should the tween reverse once reaching the endpoint)
	0  -- DelayTime
)

local characterIsInFov = false
local detectionProgress = 0 -- Variable to keep track of detection progress
local hitPlayer = nil -- Move hitPlayer variable outside the if statement

RunService.Heartbeat:Connect(function()
	if character and npc then -- Check if the character and the NPC are not null

		-- Calculate the vector between the NPC and the character
		local npcToCharacter = (head.Position - npc.Head.Position).Unit
		local npcLook = npc.Head.CFrame.LookVector
		local dotProduct = npcToCharacter:Dot(npcLook)

		if dotProduct > npcSight then
			--character is in field of view        
			characterIsInFov = true
		else
			-- character is not in field of view so we do not need to take any action
			characterIsInFov = false
		end

		-- Prepare parameters for raycasting
		local raycastParams = RaycastParams.new()
		raycastParams.FilterType = Enum.RaycastFilterType.Exclude
		raycastParams.FilterDescendantsInstances = {npc}
		raycastParams.IgnoreWater = true

		-- Perform a raycast to check if the character is in sight
		local ray = workspace:Raycast(npc.PrimaryPart.Position, (character.PrimaryPart.Position - npc.PrimaryPart.Position).Unit * npcRange, raycastParams)

		-- Check if the character is in range and in field of view
		if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
			if ray and ray.Instance.Parent == character then
				hitPlayer = PlayersService:GetPlayerFromCharacter(ray.Instance.Parent) -- This will now update the variable declared earlier
				if hitPlayer then
					-- Increase the detection progress
					detectionProgress = math.min(detectionProgress + dotProduct * 2, 1)
				end
			else
				-- Decrease the detection bar when not in sight
				detectionProgress = math.max(detectionProgress - 0.05, 0) -- Decrease the detection progress
			end
		else
			-- Decrease the detection bar when not in sight
			detectionProgress = math.max(detectionProgress - 0.05, 0) -- Decrease the detection progress
		end

		-- Animate the detection bar according to detection progress
		local tween = TweenService:Create(DetectionBar.detectionFrame.detectionBar, tweenInfo, {Size = UDim2.new(1, 0, detectionProgress, 0)})
		tween:Play()
		DetectionBar.detectionFrame.detectionBar.BackgroundColor3 = Color3.fromRGB(255, 0, 0)

		-- Check if the detection bar is filled completely before triggering the NPC detection
		if detectionProgress >= 1 then
			detectionProgress = 0 -- Reset detection progress after detection
			-- Wait for the bar to finish filling up visually, then check again
			tween.Completed:Wait() -- Wait for the current tween to complete
			
			task.wait(reactionTime)
			if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange and hitPlayer then -- Make sure hitPlayer is not nil
				print('Player detected: ', hitPlayer.Name)
			end
		end
	end
end)
#26

It’s getting slightly better but not quite right

#27

Mind sharing the .rbxl file? You can hit me up on Discord, or private message me here? It’ll be easier that way.

#28

You don’t need to tween if it’s gonna update every Heartbeat.

1 Like
#29

You mean the file for the whole place? My discord is [redacted - post solved]

1 Like
#30

You can contribute a possible fix, y’know? :wink: I’m trying.

#31 
-- Get necessary services
local RunService = game:GetService("RunService")
local PlayersService = game:GetService("Players")
local TweenService = game:GetService("TweenService")

-- Set NPC and character, along with their sight and range properties
local npc = workspace:WaitForChild("Rig")
local npcSight = 0.7
local npcRange = 100

-- GUI elements and reaction time
local player = PlayersService.LocalPlayer
local character = player.Character or player.CharacterAdded:Wait()
local head = character:WaitForChild("Head")

local playerGui = player.PlayerGui
local DetectionBar = playerGui:WaitForChild("DetectionGUI")
local reactionTime = 1.8

local characterIsInFov = false
local detectionProgress = 0 -- Variable to keep track of detection progress
local hitPlayer = nil -- Move hitPlayer variable outside the if statement

RunService.Heartbeat:Connect(function(dt)
	if character and npc then -- Check if the character and the NPC are not null

		-- Calculate the vector between the NPC and the character
		local npcToCharacter = (head.Position - npc.Head.Position).Unit
		local npcLook = npc.Head.CFrame.LookVector
		local dotProduct = npcToCharacter:Dot(npcLook)

		if dotProduct > npcSight then
			--character is in field of view        
			characterIsInFov = true
		else
			-- character is not in field of view so we do not need to take any action
			characterIsInFov = false
		end

		-- Prepare parameters for raycasting
		local raycastParams = RaycastParams.new()
		raycastParams.FilterType = Enum.RaycastFilterType.Exclude
		raycastParams.FilterDescendantsInstances = {npc}
		raycastParams.IgnoreWater = true

		-- Perform a raycast to check if the character is in sight
		local ray = workspace:Raycast(npc.PrimaryPart.Position, (character.PrimaryPart.Position - npc.PrimaryPart.Position).Unit * npcRange, raycastParams)

		-- Check if the character is in range and in field of view
		if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange then
			if ray and ray.Instance.Parent == character then
				hitPlayer = PlayersService:GetPlayerFromCharacter(ray.Instance.Parent) -- This will now update the variable declared earlier
				if hitPlayer then
					-- Increase the detection progress
					detectionProgress = math.min(detectionProgress + dotProduct * 2 * dt, 1)
				end
			else
				-- Decrease the detection bar when not in sight
				detectionProgress = math.max(detectionProgress - 0.05 * dt, 0) -- Decrease the detection progress
			end
		else
			-- Decrease the detection bar when not in sight
			detectionProgress = math.max(detectionProgress - 0.05 * dt, 0) -- Decrease the detection progress
		end

		-- Animate the detection bar according to detection progress
		local alpha = TweenService:GetValue(detectionProgress / 1, Enum.EasingStyle.Quad, Enum.EasingDirection.Out)
		DetectionBar.detectionFrame.detectionBar.Size = UDim2.new(1, 0, 0, 0):Lerp(UDim2.new(1, 0, 1, 0), alpha)
		DetectionBar.detectionFrame.detectionBar.BackgroundColor3 = Color3.fromRGB(255, 0, 0)

		-- Check if the detection bar is filled completely before triggering the NPC detection
		if detectionProgress >= 1 then
			-- detectionProgress = 0 -- Reset detection progress after detection
			-- Wait for the bar to finish filling up visually, then check again
			--tween.Completed:Wait() -- Wait for the current tween to complete

			task.wait(reactionTime)
			if characterIsInFov and (head.Position - npc.PrimaryPart.Position).Magnitude <= npcRange and hitPlayer then -- Make sure hitPlayer is not nil
				print('Player detected: ', hitPlayer.Name)
			end
		end
	end
end)

3 Likes
#32

Messed around with an attempt at this …

  1. Check if within range of NPC.
  2. Check if within angle of facing head.
  3. Add to a check loop free from hacking.

This is a test on one NPC. It will need some love,
but seems to be a viable approach for a template.
(script works as is)
.
A non-local script in ServerScriptService

task.wait(5) -- Stalling so npc is ready
local npc = workspace.Sandy.Head -- NPC's head 
local viewRange = 20

-- Function to check if the player is within the NPC's view range
local function isPlayerInNPCViewRange(player)
	local npcPosition = npc.Position
	local playerPosition = player.Character and player.Character.PrimaryPart and player.Character.PrimaryPart.Position

	if not playerPosition then
		return false
	end

	local distance = (npcPosition - playerPosition).magnitude
	return distance <= viewRange
end

-- Function to check if the player is within the 50-degree angle from the NPC's look vector
local function isPlayerInRaycastAngle(player)
	local npcLookDirection = npc.CFrame.LookVector
	local playerPosition = player.Character and player.Character.PrimaryPart and player.Character.PrimaryPart.Position

	if not playerPosition then
		return false
	end

	local directionToPlayer = (playerPosition - npc.Position).unit
	local angle = math.acos(npcLookDirection:Dot(directionToPlayer)) * (180 / math.pi)

	return angle <= 50 --  # degrees both ways from center 50x2 = 100 
end

-- Added to a stepped loop
local RunService = game:GetService("RunService")
RunService.Stepped:connect(function()
	for _, player in ipairs(game.Players:GetPlayers()) do
		if isPlayerInNPCViewRange(player) and isPlayerInRaycastAngle(player) then
			print("Player is within view range and angle!")
		end
	end
end)
#34

Solved over Discord by @AlureonTime

Thank you everyone for your contributions, I really appreciate it!

The solution involves using heartbeat with repeated checks throughout to ensure that a player has or has not been detected, and then update the detection progress based on this information and send that to the actual detection bar.

1 Like
#35

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.