Computer modeling of surfaces with arbitrary shapes

A detailed description is given of a local mathematical procedure for constructing a geometrically C/sup 1/ surface by interpolating a grid of cubic Bezier curves that meet in a quite general fashion (for example, they need not meet rectangularly). The constructed surface is a composite mosaic of independently parameterized tensor-product Bezier patches of different degrees (maximum of 6*6). Adjacent patches can be made either C/sup 1/ or C/sup 0/ continuous, as desired. The overall surface can have almost any shape that arises in practice, including the closed surfaces used in solid modeling. Because of its locality, the procedure can be applied at different times in different locations of a surface-to-be; for example, it can be used to combine preexisting smaller surfaces.<
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