Hello, I have a couple of ‘Interpolate Curve’ components in my GH definition. They are for rebuilding curves by keeping sampling points picked up from the original curve.

The ‘Interpolate Curve’ has ‘Knot Style’ option. Does anybody know what is this parameter? My GH script becomes significantly faster when I choose ‘Uniform Spacing’ but it’s set to Chord Spacing by default which makes my script slower.

Is this something like weights in Nurbs curves? that set unfirom in most cases but set as non-uniform for arcs and circles? If so, what’s the reason it is set to non-uniform by default?

Thanks.

A Nurbs curve has a knot-vector, which is just an array of numbers. The amount of values in the knot-vector is determined by the number of control-points and the degree of the curve. You can clamp a curve to a control-point by repeating the same value as often as the degree of the curve. As a result, the spacing between adjacent knots and the repetition of knot values can have a huge effect on the curve shape, without the control-points changing position or weight.

The spacing options will pick different distances between knots. The uniform spacing might produce a knot-vector like [0, 0, 0, 1, 2, 3, 4, 4, 4] for a degree=3 curve which is clamped at both ends. Whereas other spacings will take into account the physical distance between control-points, usually resulting in a more natural looking curve.

Thank you David. I was believing that Knot Vectors for a smooth curve are always 1,2,3,4,5,6,7,. Thanks.