An Offset surface, is a smooth surface (without edges, peaks, or singular points, where each point has a tangent plane. Examples: Spheres, ellipsoids, toroids, cylinders and planes), it is defined as follows:
sd[u, v] = s[u,v] + d n[u, v] and sd[u, v] = s[u,v] - d n[u, v]
s[u, v] it is a smooth surface, d = distance, n[u, v] it is the normal unitary
vector to the surfaces[u, v].
In this notebook we will obtain the offset surface of the cylinder:
{Cos[u],Sin[u],v} with d = 1.5.