OpenNurbs Trim Curve decrease Degree

Hi , could you tell me if there exist a way to decrease a trim curve’s degree in opennurbs?
think you.

Hi @user230,

Why do you want to do this? What problem does this help you solve?


– Dale

Hi @dale , I want to get a lower Degree trim curve like( p = 1 or p = 2),but in rhino ,the Degree of trim curve is 3. and I want to repalce a Bezier Triangle 's edge by the lower trim curve. so is there exists any ways to decrease the trim curve’s Degree in opennurbs or in Rhino?
Thank you!

Hi @user230,

The degree of trim curves is not always 3. Trim curves are often line curves.

trimmed_plane.3dm (33.4 KB)

OpenNURBS lets you set the trim curve to anything you want.

To change a trim curve, use ON_BrepTrim::ChangeTrimCurve().

– Dale

@dale ,thank you firstly ,maybe it help me a lot . and I will try it . thank you again.

Hi @dale , I want to modefy my trim curve’s Degree from 3 to 2;
so I need create a new curve whose Degree is 2 ,and replace it if
I use ON_brep::ChangeEdgeCurve() function,is right?
thank you.

@dale ,and the ON_brep::ChangeEdgeCurve() do not modify the curve’s Degree directly?

ON_BrepEdge::ChangeEdgeCurve does not modify the curve. It just points the edge to a different 3d curve.

– Dale

@dale ,thank you ,and i understand it.