Approximate T T -spline surface skinning
This paper considers the problem of constructing a smooth surface to fit rows of data points. A special class of T T -spline surfaces is examined, which is characterized to have a global knot vector in one parameter direction and individual knot vectors from row to row in the other parameter direction. These T T -spline surfaces are suitable for lofted surface interpolation or approximation. A skinning algorithm using these T T -spline surfaces is proposed, which does not require the knot compatibility of sectional curves. The algorithm consists of three main steps: generating sectional curves by interpolating data points of each row by a B B -spline curve; computing the control curves of a skinning surface that interpolates the sectional curves; and approximating each control curve by a B B -spline curve with fewer knots, which results in a T T -spline surface. Compared with conventional B B -spline surface skinning, the proposed T T -spline surface skinning has two advantages. First, the sectional curves and the control curves of a T T -spline surface can be constructed independently. Second, the generated T T -spline skinning surface usually has much fewer control points than a lofted B B -spline surface that fits the data points with the same error bound. Experimental examples have demonstrated the effectiveness of the proposed algorithm.
surface skinning t t -spline surfaces t t t t t b b -spline surfaces b b b b b curve interpolation