Hodographs and normals of rational curves and surfaces

نویسندگان

  • Takafumi Saito
  • Guo-Jin Wang
  • Thomas W. Sederberg
چکیده

Derivatives and normals of rational Bézier curves and surface patches are discussed. A nonuniformly scaled hodograph of a degree m × n tensor-product rational surface, which provides correct derivative direction but not magnitude, can be written as a degree (2m−2) × 2n or 2m× (2n−2) vector function in polynomial Bézier form. Likewise, the scaled normal direction is degree (3m−2)× (3n−2). Efficient methods are developed for bounding these directions and the derivative magnitude.

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عنوان ژورنال:
  • Computer Aided Geometric Design

دوره 12  شماره 

صفحات  -

تاریخ انتشار 1995