Old version of https://github.com/cozywitchcraft/anti-wallhop/

AntiWallhop.client.luau

-- StarterCharacterScripts/AntiWallhop
local RunService = game:GetService("RunService")

local CAST_POINTS = {
	-- Center line
	Vector3.new(0, -0.75, 0),
	Vector3.new(0, -0.75, 1),
	Vector3.new(0, -0.75, -1),

	-- Corners
	Vector3.new(-1, -0.75, -1),
	Vector3.new(-1, -0.75, 1),
	Vector3.new(1, -0.75, -1),
	Vector3.new(1, -0.75, 1),
}

local DebugVisuals = require(script.DebugVisuals)

local character = script.Parent

local humanoid = character:WaitForChild("Humanoid") :: Humanoid
local rootPart = character:WaitForChild("HumanoidRootPart") :: BasePart

-- Saves an __index call per frame
local isRigTypeR6 = humanoid.RigType == Enum.HumanoidRigType.R6

local params = RaycastParams.new()
params.CollisionGroup = rootPart.CollisionGroup
params.FilterType = Enum.RaycastFilterType.Exclude
params.FilterDescendantsInstances = { character }
params.RespectCanCollide = true
params.IgnoreWater = true

local postSimulationConnection

local function getHipHeight(halfSize: Vector3): number
	-- Using halfSize saves an __index call
	local hipHeight = 0.6 * halfSize.Y + humanoid.HipHeight

	-- R15 only relies on the hip height while R6 takes legs into consideration
	if isRigTypeR6 then
		local legHeight = 0
	
		local leftLeg = character:FindFirstChild("Left Leg")
		local rightLeg = character:FindFirstChild("Right Leg")

		if leftLeg then
			legHeight = math.max(legHeight, leftLeg.Size.Y)
		end

		if rightLeg then
			legHeight = math.max(legHeight, rightLeg.Size.Y)
		end
		
		hipHeight += legHeight
	end

	return hipHeight
end

local function isGrounded(): boolean
	local cframe = rootPart.CFrame
	local halfSize = 0.4 * rootPart.Size -- 0.1-stud skin
	
	local factor = 1.5

	local verticalVelocity = rootPart.AssemblyLinearVelocity.Y
	local minVelocity = -125 * halfSize.Y
	
	if verticalVelocity > 0 then
		return false -- Prevents double jumping
	elseif verticalVelocity < minVelocity then
		factor += verticalVelocity / minVelocity -- Prevents bouncing
	end
	
	local direction = getHipHeight(halfSize) * factor * -Vector3.yAxis
	
	DebugVisuals.reset()
	
	for _, point in CAST_POINTS do
		local origin = cframe:PointToWorldSpace(halfSize * point)
		local result = workspace:Raycast(origin, direction, params)
		
		DebugVisuals.drawLine(origin, direction, result)
		
		if result then
			return true
		end
	end
	
	return false
end

local function onPostSimulation(deltaTime: number)
	debug.profilebegin("AntiWallhop::onPostSimulation")
	
	local isFalling = humanoid:GetState() == Enum.HumanoidStateType.Freefall
	
	-- We're only worried about detecting the floor while the humanoid is falling.
	-- This is because wallhopping only occurs when entering the landing state pre-
	-- simulation, so we move it post-simulation.
	if isFalling and isGrounded() then
		humanoid:ChangeState(Enum.HumanoidStateType.Landed)
	end
	
	debug.profileend()
end

local function enableAntiWallhop()
	if postSimulationConnection then
		return
	end
	
	-- Disable humanoid's built-in floor detection
	humanoid:SetStateEnabled(Enum.HumanoidStateType.Landed, false)

	-- Start custom floor detection after physics simulation
	postSimulationConnection = RunService.PostSimulation:Connect(onPostSimulation)
end

local function disableAntiWallhop()
	if not postSimulationConnection then
		return
	end
	
	humanoid:SetStateEnabled(Enum.HumanoidStateType.Landed, true)

	postSimulationConnection = postSimulationConnection:Disconnect()
end

local function toggleAntiWallhop()
	if script:GetAttribute("AntiWallhopEnabled") then
		enableAntiWallhop()
	else
		disableAntiWallhop()
	end
end

local function toggleDebugVisuals()
	if script:GetAttribute("ShowDebugVisuals") then
		DebugVisuals.mount(character)
	else
		DebugVisuals.unmount()
	end
end

-- Support collision groups (e.g. player-to-player non-collision)
rootPart:GetPropertyChangedSignal("CollisionGroup"):Connect(function()
	params.CollisionGroup = rootPart.CollisionGroup
end)

script:GetAttributeChangedSignal("AntiWallhopEnabled"):Connect(toggleAntiWallhop)
script:GetAttributeChangedSignal("ShowDebugVisuals"):Connect(toggleDebugVisuals)

toggleAntiWallhop()
toggleDebugVisuals()

DebugVisuals.luau

local MAX_LINES = 7

local isShowing = false

local lines: { LineHandleAdornment } = {}
local lineIndex = 1

local terrain = workspace.Terrain

local DebugVisuals = {}

function DebugVisuals.mount(character: Model)
	if isShowing then
		return
	end
	
	for _ = 1, MAX_LINES do
		local line = Instance.new("LineHandleAdornment")
		line.Visible = false
		line.Adornee = terrain
		
		-- HACK: Lines are destroyed when character is destroyed
		line.Parent = character
		
		table.insert(lines, line)
	end
	
	isShowing = true
end

function DebugVisuals.unmount()
	if not isShowing then
		return
	end
	
	for _, line in lines do
		line:Destroy()
	end
	
	table.clear(lines)
	
	isShowing = false
end

function DebugVisuals.drawLine(origin, direction, result)
	if not isShowing then
		return
	end
	
	local color = Color3.new(result and 0 or 1, result and 1 or 0, 0)

	local line = lines[lineIndex]
	line.CFrame = CFrame.new(origin, origin + direction)
	line.Length = direction.Magnitude
	line.Thickness = 3
	line.Color3 = color
	line.Visible = true
	
	lineIndex += 1
end

function DebugVisuals.reset()
	if not isShowing then
		return
	end
	
	for _, line in lines do
		line.Visible = false
	end
	
	lineIndex = 1
end

return DebugVisuals