| | For a B-spline curve the discontinuities are localised at the knot values and between two knots values the B-spline is infinitely continuously differentiable. At a knot of range index the continuity is equal to : Degree - Mult (Index) where Degree is the degree of the basis B-spline functions and Mult the multiplicity of the knot of range Index. If for your computation you need to have B-spline curves with a minima of continuity it can be interesting to know between which knot values, a B-spline curve arc, has a continuity of given order. This algorithm computes the indexes of the knots where you should split the curve, to obtain arcs with a constant continuity given at the construction time. The splitting values are in the range [FirstUKnotValue, LastUKnotValue] (See class B-spline curve from package Geom). If you just want to compute the local derivatives on the curve you don't need to create the B-spline curve arcs, you can use the functions LocalD1, LocalD2, LocalD3, LocalDN of the class BSplineCurve. More...
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