A TRIANGULAR G(1) PATCH FROM BOUNDARY CURVES

For some applications it is necessary to fit an irregular surface to g iven data, e.g. to develop a geometric model of a human skeletal bone from computerized tomography scans. Such a surface does not always hav e easily distinguishable isoparametric lines. It is thus not convenien t to use standard global curve fitting techniques such as those based on B-splines. A global method may also smooth away essential features. A reasonable approach is to use a composite surface where individual surface patches are locally determined. To obtain some visual smoothne ss it is desirable that these patches join their neighbours in a manne r that preserves positional as well as tangent plane continuity. Sever al methods have been presented for constructing surfaces in such a man ner. A common initial stage in developing the patches is to determine a network of boundary curves. This article reports on some results usi ng boundary curves based on a recent technique for point normal interp olation.