My placement system is jittering - please help

[Illusi_nz (Illusionz)]

Hello there!

Recently (today) i realised my placement system was jittering. It didn’t jitter yesterday or anytime before today… it does jitter in the old versions as well though.

local function renderPreview()
	if cannotMovePart then return end

	if game.Players.LocalPlayer:GetAttribute("Device") == "PC" and preview ~= nil then
		plrgui.PlacementTooltip.Main.Visible = true
		plrgui.PlacementTooltip.Main.Position = UDim2.fromOffset(game.Players.LocalPlayer:GetMouse().X - 5,game.Players.LocalPlayer:GetMouse().Y)
	else
		plrgui.PlacementTooltip.Main.Visible = false
	end

	local mouseLoc = nil

	if game.Players.LocalPlayer:GetAttribute("Device") == "Mobile" then
		mouseLoc=latestClickPos
	else
		mouseLoc = UIS:GetMouseLocation()
	end

	local cast=nil
	local unitRay=nil

	if mouseLoc then
		unitRay = camera:ViewportPointToRay(mouseLoc.X,mouseLoc.Y)
		cast = workspace:Raycast(unitRay.Origin,unitRay.Direction * 1000,castParams)
	end

	if cast and preview and preview.Parent and mouseLoc and unitRay then
		local snapped = placementValidator.SnapToGrid(cast.Position)
		local normalcf = CFrame.lookAlong(cast.Position,cast.Normal)
		local relsnap = normalcf:PointToObjectSpace(snapped)
		local xVector = normalcf:VectorToWorldSpace(Vector3.xAxis*-math.sign(relsnap.X))
		local yVector = normalcf:VectorToWorldSpace(Vector3.yAxis*-math.sign(relsnap.Y))
		local cf = CFrame.fromMatrix(snapped,xVector,yVector,cast.Normal)
		preview.Position = cf:PointToWorldSpace(preview.Size/2)--extraCf.Value + cf:PointToWorldSpace(preview.Size/2)

		if preview:GetAttribute("Material") == nil then
			preview.Material = if _G.ChosenMaterial then Enum.Material[_G.ChosenMaterial] else game.ReplicatedStorage.Assets:FindFirstChild(preview.Name,true).Material --Enum.Material.SmoothPlastic
		end
	end
end

game:GetService("RunService"):BindToRenderStep("Preview",Enum.RenderPriority.Input.Value,renderPreview)

I was not the one doing all the math behind this - pretty sure i got it from some youtube tutorial. Its especially jittering on the Y axis where it’s going under the floor

If you guys have any idea on how I can solve this it will be appreciated! : )

Thanks!

[Illusi_nz (Illusionz)]

my snapping module was the reason