\input zb-basic
\input zb-ioport
\iteman{io-port 00822288}
\itemau{V\'arady, T.; Rockwood, A.P.}
\itemti{Vertex blending based on the setback split.}
\itemso{D{\ae}hlen, Morten (ed.) et al., Mathematical methods for curves and surfaces. Papers from an international conference held June 16-21, 1994 in Ulvik, Norway. Nashville, TN: Vanderbilt University Press. 527-542 (1995).}
\itemab
Summary: A new multisided patch scheme is presented which interpolates an even number of boundary curves. Its primary application is setback type vertex blending to provide a smooth transition between converging edge blends around a vertex. It satisfies positional and tangential constraints derived from edge blends and primary faces to be blended. The scheme is based on a new subdivision of the $n$-sided hole using low degree (rational) polynomial patches. After a related twist compatibility analysis the constraints for the subdividing curves are described. Finally, different alternatives to satisfy internal $G^1$ continuity are shown based on the technique of common cross-derivative functions.
\itemrv{~}
\itemcc{}
\itemut{smooth transition surfaces; geometric modelling; blending surfaces; setback type vertex blending}
\itemli{}
\end