Invariant-geometry conditions for the rational bi-quadratic Bézier surfaces

نویسنده

  • Helmut E. Bez
چکیده

A generalization of Patterson’s work (Patterson, 1985), on the invariants of the rational Bézier curves, to the case of surfaces is presented. An equation for the determination of the invariants for surfaces of degree (n, n) is derived and solved for the bi-quadratics – for which it is shown that seven independent, invariant functions exist. Explicit forms of the invariants are derived and a number of applications are presented.

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عنوان ژورنال:
  • Computer Aided Geometric Design

دوره 26  شماره 

صفحات  -

تاریخ انتشار 2009