DIRECT MANIPULATION OF GENERALIZED CYLINDERS BASED ON B-SPLINE MOTION

We present a direct manipulation technique that allows interactive con trol of the shape of generalized cylinders. We interpret the generaliz ed cylinder as the sweep surface of a planar cross-sectional B-spline curve under B-spline motion. The generated surface is a NURBS surface that interpolates a given sequence of cross-sectional curves along a s keleton curve. Directly manipulating a surface point on the generalize d cylinder modifies the cross-sectional shape and its motion and defor ms the generalized cylinder to interpolate the exact point location sp ecified by the user. The surface is deformed by a target tracking proc edure.