English

Using Geometric Symmetries to Achieve Super-Smoothness for Cubic Powell-Sabin Splines

Numerical Analysis 2024-11-11 v1 Numerical Analysis

Abstract

In this paper, we investigate C2C^2 super-smoothness of the full C1C^1 cubic spline space on a Powell-Sabin refined triangulation, for which a B-spline basis can be constructed. Blossoming is used to identify the C2C^2 smoothness conditions between the functionals of the dual basis. Some of these conditions can be enforced without difficulty on general triangulations. Others are more involved but greatly simplify if the triangulation and its corresponding Powell-Sabin refinement possess certain symmetries. Furthermore, it is shown how the C2C^2 smoothness constraints can be integrated into the spline representation by reducing the set of basis functions. As an application of the super-smooth basis functions, a reduced spline space is introduced that maintains the cubic precision of the full C1C^1 spline space.

Keywords

Cite

@article{arxiv.2411.05170,
  title  = {Using Geometric Symmetries to Achieve Super-Smoothness for Cubic Powell-Sabin Splines},
  author = {Jan Grošelj and Hendrik Speleers},
  journal= {arXiv preprint arXiv:2411.05170},
  year   = {2024}
}