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arXiv · 1610.05351

Spline surfaces with T-junctions

Kestutis Karciauskas·Daniele Panozzo·Jörg Peters
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Abstract

This paper develops a new way to create smooth piecewise polynomial free-form spline surfaces from quad- meshes that include T-junctions, where surface strips start or terminate. All mesh nodes can be interpreted as control points of geometrically-smooth, piecewise polynomials that we call GT-splines. GT-splines are B-spline-like and cover T-junctions by two or four patches of degree bi-4. They complement multi-sided surface constructions in generating free-form surfaces with adaptive layout. Since GT-splines do not require a global coordination of knot intervals, GT-constructions are easy to deploy and can provide smooth surfaces with T-junctions where T-splines can not have a smooth parameterization. GT-constructions display a uniform highlight line distribution on input meshes where alternatives, such as Catmull-Clark subdivision, exhibit oscillations.

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Kestutis Karciauskas, Daniele Panozzo, Jörg Peters. 2016-10-17. Spline surfaces with T-junctions. https://arxiv.org/abs/1610.05351

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