Determine the points on the curve:
Make out the equation of a Bezier curve; determine the points on the curve for t = 0, 1/4, 1/2, 3/4, and 1 and plot the curve for the following data. The coordinates of the four control points specified by
V0 = [0, 0, 0]
V1 = [0, 2, 0]
V2 = [4, 2, 0]
V3 = [4, 0, 0]
Solution
The number of control points is 4 (that is, 4 = n + 1), we set n = 3. Then we have the Bezier curve function as follows:
V (t ) = V0 (1 - t)3 + 3V1 t (1 - t )2 + 3V2 t 2 (1 - t ) + V3 t 3 0 ≤ t ≤ 1
Substituting the values t = 0, 1/4, 1/2, 3/4, 1 into this equation, we have
V (0) = V0 = [0, 0, 0]T
V (1/4) = (27/64) V0 + (27/64) V 1 + (9/64) V 2 +(1/64) V3 =,[(5/8),(9/8) , 0]T
V (1/2) = (1/8) V0 + (3/8) V 1 + (3/8) V 2 +(1/8) V3 =,[(2),(3/2) , 0]T
V (3/4) = (1/64) V0 + (9/64) V 1 + (27/64) V 2 =,[(22/8),(9/8) , 0]T
V (1) = [4, 0, 0]T