Rhino _connect command in grasshopper

Hey guys!
In Rhino there is this _connect command. There are two curves intersecting by clicking on them. I’m looking for a similar command in grasshopper. The aim is to extend the continuity of lines and arcs to generate the intersections.
I already tried the extend and intersection component in combination. This doesn’t give reliable results because I can’t exactly define the value of the extension. If it is too small, it can happen that the curves do not intersect, if it is too large, several intersection points will occur.


Best would be a command that works exactly like the rhino _connect command.
Does anyone have an idea?

Visit and check if the linked topic can help you.

Thanks, but i need something that works also with arcs. Something like a “curve-curve” intersection.

Have you tried the two connect curve components?

This only works in combination with the extend component because the curves have to touch each other. I would like to do without the extend component because i can’t calculate the exact length of the extension.

Not like that. Please check again.

Doesn’t work like i need it.

Maybe i need to explain the problem a little better, sorry. Hopefully this helps to follow me:


I think i need a totally diffrent approach. Something like a python script to calculate the intersection with numpy or something, but i’m not used to it.
Does somebody has an other idea?

This may not be the solution you want, but you can use this method in case you have suggested.


Closed Curve By ExtensionV2.gh (13.2 KB)

We are getting closer but there is still a problem with the extension component.
As long as i am using the extension component there will be a problem with the right value. The point distance with a factor is not related for diffrent angles for example. Very acute angles are not really working this way.

Does somebody know how the rhino _connect command exactly works?
Is there a way to implement rhino commands in grasshopper?

Is there a way to implement rhino commands in grasshopper?

Yes, but they will happen in rhino, not grasshopper. Grasshopper will just trigger the command. Lunchbox has a component that let’s you type in and use rhino commands that way. Maybe someone like @dale can expose that command in Rhinocommon.

Would be very helpful! @dale