Hi, I’ve been trying to understand better about degree of curves in general. The points being used to draw the curve minus 1 equals to degree, but when selecting to draw a curve with degree of 3, but have more points than 4, using curvaturegraph the curvature is discontinued at the third point …

[image] Toshiaki_Takano: I’ve been trying to understand better about degree of curves in general. The points being used to draw the curve minus 1 equals to degree, but when selecting to draw a curve with degree of 3, but have more points than 4, using curvaturegraph the curvature is discontin…

david summed it up pretty nice in one sentence nothing to add, only that you can combat discontinuity quite well with the command fair, sometimes hitting it a few times of course. [image] [image] John_Brock: This is a good reference too: Rhino - What are NURBS? do you have any idea how i …

@RIL Thank you. The drawing helps in understanding better.

@John_Brock Thank you for the link. I need to go through it couple of times… May come back to you for some questions later…

@davidcockey For the curves of deg3 drawn with 6control points, is it so that where the discontinuity of the curve is, so kink of the rate of change in curvature, is where two curves are connected at a tangent? In that case, is the curve after that kink a deg2 curve as it is drawn using 3 control…

@RichardZ In the screenshot attached, does the curve on the right still have a difference in the rate of curvature or is it slightly off if you zoom in? I’ve yet to try the fair command…

At a kink in the curvature graph the curvature is continuous, but the rate at which the curvature changes as you move along the curve is discontinuous at the kink. A discontinuity in curvature results in a discontinuity in the curvature graph A degree 3 curves has continuous curvature unless two o…

@davidcockey Thank you for your detail explanation. I’m starting to understand, but seems I need to study further. So deg 2 crv promise tangency, deg 3 crv tangency& curvature continuous unless stacked. Deg 4 crv will I suppose add continuous rate of curvature curve? Seems I need to go study cu…

Years ago, there was a really good beginning tutorial from one of the marine designers, that started with an introduction to NURBS curves that described all of this very well. Sadly, I have lost track of it.

Is this the document? fairing.pdf (165.6 KB)

Degree of Curves: Is there any good tutorials?

Rhino Rhino for Windows

Toshiaki_Takano June 29, 2017, 12:33am 17

@scottd @John_Brock
Thank you both!
I’ll have a look through it. Thanks again!

Is there a good way to get rid of the seam of this revolved curve?

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Degree of Curves: Is there any good tutorials?

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