Bezier3

p_{11} = Dilate(p_2, u, p_1)
p_{21} = Dilate(p_3, u, p_2)
p_{01} = Dilate(p_1, u, p_0)
p_{02} = Dilate(p_{11}, u, p_{01})
p_{12} = Dilate(p_{21}, u, p_{11})
p_{03} = Dilate(p_{12}, u, p_{02})