Skeleton Based Parametric Solid Models: Ball B-Spline Curves

This paper proposes a parametric solid representation of freeform tubular objects - Ball B-Spline Curves (BBSCs), which are skeleton based parametric solid model. Their fundamental properties, algorithms and modeling methods are investigated. BBSC directly defines objects in B-Spline function form (not a procedure method, like sweeping), that uses control ball instead of control point in B-Spline curve. BBSC describes not only every point inside 3D solid objects, but also provides its center curve in B-Spline form directly. So the representation is more flexible for modeling, manipulation and deformation.