space curve has a parametric form x
- This provides a mapping from one variable
(t) to R3
surface has a parametric form s
- This provides a mapping from two
variables (u, v) to R3
derivative of a surface can be taken with respect to u and v. These
derivatives can be used to find the tangent to the surface, which is a now a
plane that grazes the surface at a given point.
surface normal n
vector orthogonal to the tangent plane.