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arXiv · 1312.0030

A Hermite interpolatory subdivision scheme for $C^2$-quintics on the Powell-Sabin 12-split

Tom Lyche·Georg Muntingh
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Abstract

In order to construct a $C^1$-quadratic spline over an arbitrary triangulation, one can split each triangle into 12 subtriangles, resulting in a finer triangulation known as the Powell-Sabin 12-split. It has been shown previously that the corresponding spline surface can be plotted quickly by means of a Hermite subdivision scheme. In this paper we introduce a nodal macro-element on the 12-split for the space of quintic splines that are locally $C^3$ and globally $C^2$. For quickly evaluating any such spline, a Hermite subdivision scheme is derived, implemented, and tested in the computer algebra system Sage. Using the available first derivatives for Phong shading, visually appealing plots can be generated after just a couple of refinements.

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Tom Lyche, Georg Muntingh. 2013-11-29. A Hermite interpolatory subdivision scheme for $C^2$-quintics on the Powell-Sabin 12-split. https://doi.org/10.1016/j.cagd.2014.03.004

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