“Watertight trimmed NURBS” by Sederberg, Finnigan, Li, Lin and Ipson

  • ©Thomas (Tom) W. Sederberg, G Thomas Finnigan, Xin Li, Hongwei Lin, and Heather Ipson




    Watertight trimmed NURBS



    This paper addresses the long-standing problem of the unavoidable gaps that arise when expressing the intersection of two NURBS surfaces using conventional trimmed-NURBS representation. The solution converts each trimmed NURBS into an untrimmed T-Spline, and then merges the untrimmed T-Splines into a single, watertight model. The solution enables watertight fillets of NURBS models, as well as arbitrary feature curves that do not have to follow iso-parameter curves. The resulting T-Spline representation can be exported without error as a collection of NURBS surfaces.


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