Any way to match the tangency of one curve to another in GH?

Replies to This Discussion

Permalink Reply by David Stasiuk on February 4, 2013 at 4:58am

I've never really dug into the point/weight/knot values of a nurbs curve, so this is super rough.  Just checked this out:

http://www.saccade.com/writing/graphics/KnotVectors.pdf

Using that, here's a quick and dirty definition that joins two curves into one.  Both curves are oriented in the same general direction, and the curve that gets changed is the "back" one of the two.  I am sure there are many other better ways to do this, and to make it more flexible, but I just sketched it super quick.  Basically the curve to remain fixed shoots off a new point from the end that's supposed to match, which replaces the control point at the matching end of the curve to change.  You can adjust how far out from the fixed curve the new control point shoots out.

Hope it helps...would love to see any refinements or other solutions.

Attachments:

• nurbs_match.gh, 12 KB

Permalink Reply by Michiel Cornelissen on February 4, 2013 at 5:37am

This looks interesting! Will have a look.

Permalink Reply by Michiel Cornelissen on February 5, 2013 at 6:06am

Finally got around to checking it, that's a pretty nice definition you made! I think I'll try to mock up a simpler version to just put the first two control points of the second curve in the line of the last two control points of the first curve- that's all I need right now. It's sort of at the fringes of my GH capabilities, but it's a nice challenge.

Permalink Reply by Michiel Cornelissen on February 5, 2013 at 6:42am

Attached a very simplified version, just matches the last two control points of one curve to the direction of the second; plus a weight factor to control the influence of the second curve. Just what I needed, thanks for the help!

Attachments:

• 2013 02 05 one curve tangent to another.gh, 7 KB

Permalink Reply by David Rutten on February 4, 2013 at 5:10am

There doesn't appear to be a way to do this. I found the C++ algorithms in Rhino source and I can move them to RhinoCommon at which point they'll be available to Grasshopper.

--

David Rutten

david@mcneel.com

Poprad, Slovakia

Permalink Reply by Michiel Cornelissen on February 4, 2013 at 5:37am

That'd be really nice addition to GH, thanks David!

Permalink Reply by kakbrus on December 17, 2017 at 8:56pm

thanks , you artikel very good, me really like you artickel thanks you so much.

five nights at freddy's