"Hash" spline patches allow you to build complex, organic shapes and animations
using spline curves. These patches are used in commercial
"Animated Master" 3D Modeller by
Martin D. Hash (see also
algorithm for real-time spline-based character animation).
The same spline patches are used in "sPatch" (Ver 1.5, Copyright 1996-1998 by Mike Clifton) and "HamaPatch" free spline-based modelling tools for Windows95 and NT.
|All verteses can be stored as an array, then indexed face set (IFS) of triangular spline patches (and barycentric coordinates) can be used to represent an object. The VRML viewer "Cortona" supports "SplineFaceSet" VRML extension node similar to the standard IFS. "The method of spline representation of geometry objects is based on three-cubic spline interpolation, using incoming polygonal data (control vertices)." See "spline tetrahedron" and "spline cube" demos. But I don't know how to combine these patches C1 smoothly and if there is a handy method to build all the heap of points in an authoring tool. Are triangular patches useful for scanned objects?|