Description Retrieves the parameters of an existing spline curve.
Syntax GetSplineCurve n, entity, degree, breakpoints(), coeffs()
Parameters n As Long Node number of the spline curve whose parameters are being retrieved.
entity As T_ENTITY After calling GetSplineCurve, this structure variable contains the generic information about the curve (parent on the tree, traceability, name, etc.).
degree As Long After calling GetSplineCurve, this variable contains polynomial degree for the spline curve segments.
breakpoints() As Double After calling GetSplineCurve, this variable array contains the breakpoint list for the spline curve. The breakpoint values should be increasing and will define the range of the parametric variable for each segment. For example, if breakpoints() has an upper bound of 2, with the values [0, 2, 3], this means that there will be two segments in the spline curve. The first segment has length 2, with the parametric variable ranging from 0 to 2, and the second segment has length 1 with the parametric variable ranging from 0 to 1.
coeffs() As Double After calling GetSplineCurve, this 3xN variable array contains the coefficients of the polynomial segments for the spline curve. The first dimension corresponds to the segment columns as seen in the GUI, which contain the coefficients for the polynomials in X, Y and Z, respectively. The second dimension corresponds to the segment rows as seen in the GUI, where N is (degree+1)*(Nbreakpoints-1). For example, if breakpoints() has the values [0,2,3], then Nbreakpoints = 3 and there are 2 segments. If degree is 1 (i.e. segments are linear), then the second dimension of coefs() has size (2)*(2) = 4. The first two index values, 0 and 1, correspond to the coefficients of the first segment and the second two index values, 2 and 3, correspond to the coefficients of the second segment.
See Also
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