A unified interpolatory subdivision scheme for quadrilateral meshes

For approximating subdivision schemes, there are several unified frameworks for effectively constructing subdivision surfaces generalizing splines of an arbitrary degree. In this article, we present a similar unified framework for interpolatory subdivision schemes. We first decompose the 2n-point interpolatory curve subdivision scheme into repeated local operations. By extending the repeated local operations to quadrilateral meshes, an efficient algorithm can be further derived for interpolatory surface subdivision. Depending on the number n of repeated local operations, the continuity of the limit curve or surface can be of an arbitrary order CL, except in the surface case at a limited number of extraordinary vertices where C1 continuity with bounded curvature is obtained. Boundary rules built upon repeated local operations are also presented.