C 1 Surface Splines *
نویسنده
چکیده
The constructionof quadraticC 1 surfacesfrom B-spline control points is generalized to a wider class of control meshes capable of outlining arbitrary free-form surfaces in space. Irregular meshes with non quadrilateral cells and more or fewer than four cells meeting at a point are allowed so that arbitrary free-form surfaces with or without boundary can be modeled in the same conceptual frame work as tensor-product B-splines. That is, the mesh points serve as control points of a smooth piecewise polynomial surface representation that is local, evaluates by averaging and obeys the convex hull property. For a regular region of the input mesh, the representation reduces to the standard quadratic spline. In general, any surface spline can be represented by Bernstein-B ezier patches of degree two and three. According to the user's choice, these patches can be polynomial or rational, three-sided, four-sided or a combination thereof.
منابع مشابه
Biquartic C1-surface splines over irregular meshes
C 1-surface splines deene tangent continuous surfaces from control points in the manner of tensor-product (B-)splines, but allow a wider class of control meshes capable of outlining arbitrary free-form surfaces with or without boundary. In particular, irregular meshes with non quadrilateral cells and more or fewer than four cells meeting at a point can be input and are treated in the same conce...
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