Bézier surface

Bézier surfaces are a species of mathematical spline used in computer graphics, computer-aided design, and finite element modeling.

Similar to interpolation in many respects, a key difference is that the surface does not, in general, pass through the central control points; rather, it is "stretched" toward them as though each were an attractive force.

The geometry of a single bicubic patch is thus completely defined by a set of 16 control points.

They require fewer points (and thus less memory) to represent curved surfaces, are easier to manipulate, and have much better continuity properties.

In addition, other common parametric surfaces such as spheres and cylinders can be well approximated by relatively small numbers of cubic Bézier patches.