C(u) = [X(u) Y(u) Z(u)]
where u varies in some domain (e.g., [0,1]).
A Bezier surface patch is a vector-valued function of two variables:
S(u,v) = [X(u,v) Y(u,v) Z(u,v)]
where u and v can both vary in some domain.
For each u (or u and v, in the case of a surface), the formula for C() (or S()) calculates a point on the curve (or surface). To use an evaluator, first define the function C() or S().
->See also: Hermite Curves, Bezier Curves, B(asis)-Splines, NURBS