A triangular G1 patch from boundary curves

Computer Aided Design, Elsevier, pp.113-123, 1996

MESHING
RESEARCH
CORNER

Department of Computer Science, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada

Abstract
For some applications it is necessary to fit an irregular surface to given data, e.g. to develop a geometric model of a human skeletal bone from computerized tomography scans. Such a surface does not always have easily distinguishable isoparametric lines. It is thus not convenient 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 smoothness it is desirable that these patches join their neighbours in a manner that preserves positional as well as tangent plane continuity. Several methods have been presented for constructing surfaces in such a manner. A common initial stage in devel- oping the patches is to determine a network of boundary curves. This article reports on some results using boundary curves based on a recent technique for point normal interpolation.