Modification of n-sided patches based on variation of blending functions

By introducing the edge-based blending function, derived from the surface-based function, we can capture the effects of the edges on the shape of the n-sided patch more directly. Designers can manipulate the edge-based blending function, as well as the geometry of the boundary curves, to design and modify the patch shape. We discuss the derivation of the edge-based blending function, the ease of design and the connection of several patches with G/sup 1/ continuity. We demonstrate its validity by modifying rectangular patches according to its changes.