--Create a window
        window = Window:Create()
        context = Context:Create(window)
        world = World:Create() 
        local camera = Camera:Create() 
        camera:SetRotation(35,0,0) 
        camera:Move(0,0,-4) 
        local light = DirectionalLight:Create() 
        light:SetRotation(35,35,0) 
        
         --Average normal
        local model = Model:Cylinder() 
        model:SetColor(1.0,0.0,0.0) 
        model:SetPosition(-2.0,0.0,0.0) 
        local surface = model:GetSurface(0) 
        surface:UpdateNormals(false) 

         --Angular threshold at 180 degrees
        model = Model:Cylinder() 
        model:SetColor(0.0,1.0,0.0) 
        model:SetPosition(0.0,0.0,0.0) 
        surface = model:GetSurface(0) 
        surface:UpdateNormals(true,0.01,180) 

         --Angular threshold at 25 degrees
        model = Model:Cylinder() 
        model:SetColor(0.0,0.0,1.0) 
        model:SetPosition(2.0,0.0,0.0) 
        surface = model:GetSurface(0) 
        surface:UpdateNormals(true,0.01,25) 
        
        while true do

        if window:Closed() or window:KeyHit(Key.Escape) then return false end

        Time:Update()
        world:Update()
        world:Render()
        context:Sync()

        end