Change degree but dont rebuild

I seem to recall that change degree used to keep point number and position. Now it rebuilds it to something similar but not really. I’m kind of struggling to see the usefulness of this.
On the other side, I would like to find a way to simply change degree in rhino without changing the control points.

Hello - ChangeDegree does just that - unlike Rebuild, it does not change the shape of the input. But changing the degree will change the control points - (why else would you do this?) - the curve or surface itself will not change in shape.


Thanks Pascal,
But it does change the shape. It must, at lest for some cases, infact I think that for the purpose of keeping the shape similarity rebuild is more effective. But maybe it depends on the case.
I just was trying to do a curve degree demonstration by showing how the path interpolation changes in with same set of points. I thought I could simply use change degree, but probably grasshopper is the way.

It depends on the “direction” you are changing the degree. If you increase the degree, the shape should not change (within tolerance I think), but if you decrease the degree it does.

If the input curve is multispan (number of control points greater than the curve degree + 1) then increasing the degree with ChangeDegree and Deform=No will retain the exact shape of the input cuve but will introduce multiknots. Increasing degree with ChangeDegree and Deform=Yes will not introduce multiknots but the higher degree curve will not be exactly the same shape as the lower degree input curve.

This is because the continuity between spans of the lower degree curve is less than the continuity without multikinots for the higer degree curve. (G2 for degree 3 vs G4 for degree 5 for example.) The multiknots allow for the lower continuity in the higher degree curve so that the higher degree and lower degree multispan curves match exactly.

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I must say that Deform=No is pretty amazing.
I still dont get the point of deform=yes

Try point editing the results and you’ll see.

Hi Guido - yes, sorry, what I said was misleading - I should have specified : Increasing the degree (usually what is done, to increase the point count) will not change the shape, decreasing usually will. I use ChangeDegree most often in increasing the degree of single span curves or surfaces. For complex geometry, Rebuild is indeed generally more useful.


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