An influence-knot set based new local refinement algorithm for T-spline surfaces

Local refinement is widely applied in surface modeling. This paper proposes the concept of influence knot set, and uses it to establish a new algorithm for the local refinement of T-spline surfaces, whose effectiveness is demonstrated by several examples. Compared with existing algorithms, the present one may have two advantages: (a) it does not produce excessive propagation of control points because the number of additional control points is reduced; (b) it simplifies the process of judging whether an additional control point needs to be added or not, and so the final T-mesh topology can be obtained more easily.