Making a rotated brick grow only one one side?

Hello, I'm trying to make some kind of trapdoor,

The way it works is like this:

When you close it, it kind of slides and grows so that you have the impression it is closing. A little like a garage door but on the ground.

I'm trying to find the exact formula to make it look good.

So far I have :

h1.Size=Vector3.new(h1.Size.X+.482,h1.Size.Y,h1.Size.Z) h1.CFrame=CFrame.new(q1.X-.241,q1.Y,q1.Z+.0241)*CFrame.Angles(math.rad(0),math.rad(15),math.rad(-0))

But that wont work.

h1 being the door part and q1 being its position

Free model is here

Here's some code that should work.

Note - use the Front Surface as the edge of the door that closes, and increment must be greater than one. I used 1.01

Put this in a server script...

New Answer:

function difference(n1,n2)
	return math.abs(n2-n1)
end

function invertFace(face)
	if face == Enum.NormalId.Front then
		return Enum.NormalId.Back
	elseif face == Enum.NormalId.Back then
		return Enum.NormalId.Front
	elseif face == Enum.NormalId.Top then
		return Enum.NormalId.Bottom
	elseif face == Enum.NormalId.Bottom then
		return Enum.NormalId.Top
	elseif face == Enum.NormalId.Left then
		return Enum.NormalId.Right
	elseif face == Enum.NormalId.Right then
		return Enum.NormalId.Left
	end
end
function getPositiveFace(face)
	if face == Enum.NormalId.Top or face == Enum.NormalId.Right or face == Enum.NormalId.Back then
		return face
	else
		return invertFace(face)
	end
end
function getFacePosition(object,face)
	return ((object.CFrame * CFrame.new(object.Size/2 * Vector3.FromNormalId(face))).p * Vector3.FromNormalId(getPositiveFace(face))).magnitude
end
lastDistR = 0
lastDistL = 0
lastDistF = 0
lastDistB = 0
lastDistT = 0
lastDistB2 = 0
function closeDoor(part,side, distance)
	--local part = handles.Adornee
	if part == nil then return end
	

	
	if tostring(side) == "Enum.NormalId.Front" then
		if distance - lastDistF > 1 then
			local newDist = math.floor(distance - lastDistF)
			local cf = part.CFrame
			local lv = cf.lookVector
			local cf2 = part.CFrame
			local size = part.Size
			part.Size = Vector3.new(part.Size.x, part.Size.y, part.Size.z + newDist)
			if part.Size == size then
				part.CFrame = cf2 + lv * (0.5*newDist)
				cf2 = part.CFrame
			end
			part.CFrame = cf2 + lv * (0.5*newDist)
			lastDistF = lastDistF + newDist
		else
			if distance - lastDistF < -1 and part.Size.z + math.ceil(distance - lastDistF) < 1 then
				local newDist = -(part.Size.z - 1)
				local cf = part.CFrame
				local lv = cf.lookVector
				local cf2 = part.CFrame
				local size = part.Size
				part.Size = Vector3.new(part.Size.x, part.Size.y, part.Size.z + newDist)
				if part.Size == size then
					part.CFrame = cf2 + lv * (0.5*newDist)
					cf2 = part.CFrame
				end
				part.CFrame = cf2 + lv * (0.5*newDist)
				lastDistF = lastDistF + newDist
			else
				if distance - lastDistF < -1 and part.Size.z + math.ceil(distance - lastDistF) > 0  then
					local newDist = math.ceil(distance - lastDistF)
					local cf = part.CFrame
					local lv = cf.lookVector
					local cf2 = part.CFrame
					local size = part.Size
					part.Size = Vector3.new(part.Size.x, part.Size.y, part.Size.z + newDist)
					if part.Size == size then
						part.CFrame = cf2 + lv * (0.5*newDist)
						cf2 = part.CFrame
					end
					part.CFrame = cf2 + lv * (0.5*newDist)
					lastDistF = lastDistF + newDist
				end
			end
		end
	end

	

	

	
end
local increment = 1.01
local max_size = 10
local obj1 = script.Parent
local eye = script.Parent.Parent.eye
local face1 = Enum.NormalId.Front

	
		local Direction = obj1.CFrame.lookVector --+ Vector3.new(0,0,0)
		
		local Look = (Direction).unit --for whatever reason -90 had to be changed to 90
		local ray = Ray.new(obj1.CFrame.p, Look*500) -- -5 to clear the entrance ramp elevator with the ray and * 300 is the distance of the ray - you must be this close to the ground
		local ignorelist = {}
		table.insert(ignorelist,obj1)		
	--	table.insert(ignorelist,eye)			
					
		local part3, position = game.Workspace:FindPartOnRayWithIgnoreList(ray,ignorelist)
		print("part found: "..part3.Name)
		
		max_size = (part3.Position- obj1.CFrame.p).magnitude + 2
		--max_size = max_size + (obj1.Size/2 * Vector3.FromNormalId(Enum.NormalId.Back)).magnitude 
		print("max_size: "..max_size)
local function ontouched(hit)
	
	if hit.Parent:FindFirstChild("Humanoid") then
		local total = 0
		while total < max_size do
		
			closeDoor(obj1,face1,(increment*-1.0))
			lastDistF	 = 0
			wait(.001)	
			total = total + increment
		end
		wait(5)
		local total = 0
		while total < max_size do
		
			closeDoor(obj1,face1,increment)
			lastDistF	 = 0
			wait(.001)	
			total = total + increment
		end
		wait(5)
	end
	
end

script.Parent.Touched:connect(ontouched)