Grid

local player = game.Players.LocalPlayer
local mouse = player:GetMouse()

local Grid = game.Workspace.Grid
local GridSize = (4/2)
local Offset = .2
local Marker = game.Workspace.Marker

local PosX = Marker.CFrame.X
local PosY = Marker.CFrame.Y
local PosZ = Marker.CFrame.Z

mouse.Move:Connect(function()
	if mouse.Target == Grid then
		mouse.TargetFilter = game.Workspace.Marker
		Marker.Position = Vector3.new((math.floor(mouse.Hit.X / GridSize +.5 ) * GridSize) - .575, mouse.Hit.Y, (math.floor(mouse.Hit.Z / GridSize + .5) * GridSize) )
	end
end)
local Done = false
local part
local OldMarker
mouse.Button1Down:Connect(function()
	if not Done then
        OldMarker = Marker:Clone()
		OldMarker.Parent = game.Workspace
        OldMarker.CFrame = Marker.CFrame
		part = Instance.new("Part")
		part.Size = Vector3.new(.1,Grid.Size.Y,.1)
		part.Anchored = true
		part.Position = Marker.Position
		part.TopSurface = Enum.SurfaceType.Smooth
		part.Parent = game.Workspace
		mouse.TargetFilter = part
		Done = true
	elseif Done then
		Done = false
		OldMarker:Destroy()
	end
end)
local Midpoint = function(x1, x2)

	local Answer = ((x2 + x1)/2)

	return Answer

end
mouse.Button1Up:Connect(function()
	wait()
	spawn(function()
		while Done do
			part.Size = Vector3.new(math.abs((Marker.Position.X - OldMarker.Position.X)), .1, math.abs((Marker.Position.Z - OldMarker.Position.Z)))
			part.CFrame = CFrame.new(Midpoint(OldMarker.CFrame.X, Marker.CFrame.X), part.Position.Y, Midpoint(OldMarker.CFrame.Z, Marker.CFrame.Z))
			wait()
		end
	end)
end)