Connecting curve endpoints to points on another curve

Replies to This Discussion

Permalink Reply by Carl Hill on August 27, 2015 at 10:06am

Either my request was too simple or too complex........but with no response in 21 hours it is not likely in between.  I have attempted another path to get the end result without connecting the endpoints of a line in Rhino to those defined on a circle in GH but still need to understand how to do that.

Thanks to anyone that can provide some guidance....... :)

Permalink Reply by Joseph Oster on August 27, 2015 at 10:14am

Or perhaps it's because you didn't post any code and your explanation with pics alone isn't clear about what you are trying to achieve?

Permalink Reply by Carl Hill on August 27, 2015 at 10:40am

Joseph.......thank you for the reply. 

I must not understand what i need to post.  The code i have was in the screenshots.  Not much, but i have no idea as to what to do next to connect the Rhino curve endpoints to the points on the GH circles.  It doesn't seem to be too difficult but...like i said.......at this point on my learning curve i don't have the info needed to do so.

The purpose is to create pipes to Project/FlowAlongSrf/Splop from one end to the other on the surface of the cylinder after twisting them about the axis approx 90 degrees. 

My other path was to create straight curves between the points and use variable pipe.  That much worked and i got the pipes where i wanted them.  Then, I downloaded Jackalope and attempted Splop.  That sortof worked......but it ended up a huge mess.  i will be simplifying my approach and taking it in smaller steps on this path.  But i still would like to know how to connect Rhino curve endpoints to GH points.

thanks again..........

Permalink Reply by Joseph Oster on August 27, 2015 at 10:51am

Screen shots of code, especially when it is icons instead of labels, is virtually useless to me.  I'm never going to spend time wiring up a replica of a screen shot before even attempting to solve a puzzle.

I hear two goals:

1. "to create pipes to Project/FlowAlongSrf/Splop from one end to the other on the surface of the cylinder after twisting them about the axis approx 90 degrees."
2. "to connect Rhino curve endpoints to GH points".

#2 is trivial, so there must be a misunderstanding...?  Are you talking about points that already have the same X/Y/Z coordinates?  Or "connecting" points across a gap?  It really isn't as clear as you think.

#1 sounds like you want a barber pole effect?  With pipes instead of stripes?

Permalink Reply by Carl Hill on August 27, 2015 at 11:04am

Okay.........attach the actual GH file.  Duh..I should have thought about that.  Good feedback - thanks.  Next time i will do that.  Also, thanks for the GH Ning use coaching....... :)

I no longer have that file...so if there is not an easy explanation don't worry about it.......I will get it sooner or later. 

The end goal is #1.  Number 2 was my first path and i got stuck trying to connect the Rhino Curve Endpoints to the GH Circle points. I had two sets of outputs......points on the circles and endpoints on the curves.....I needed to be able to make them the same points. 

Regarding #2, I placed the GH circles at the end of the curves and divided the GH circles.  I was just attempting to have GH create GH copies of the curves at the dividing points on the circles.  I am certain it is easy, I may even have the info i need to do it.....it is just not coming into my brain after a lot of searching the GH Intro videos, so i requested help.

Thanks again...

Permalink Reply by Joseph Oster on August 27, 2015 at 11:42am

It is very easy "to have GH create GH copies of the curves at the dividing points on the circles".  In fact, you don't need the circles at all, just use a polar array ('Transform | Array | Polar').  But I don't think that alone helps you get the barber pole spiral effect.

One of my points of confusion here is that it sounds like you want to twist copies of the Rhino curve (which is not a straight line) around a cylinder?

So I still don't have a clear enough picture to offer much help.

Note: the 'Crv' input here is a spiral created in Rhino, internalized as a GH parameter.

Attachments:

• barber_pipe_20150827a.gh, 9 KB

Permalink Reply by Carl Hill on August 27, 2015 at 12:49pm

Joseph......You have been great help.  Yes, the idea was to create pipes from the curves and as you said, barberpole them around the surface.  That was going to be texture on the compound curve surface.  Your confusion has gotten me thinking that doing that with a surface profile curve is not likely going to get to my objective.  If i used the pipes to create a new surface it might....and that is an idea i might want to try. 

I have been working this morning on my second approach using the Splop component in GH.  There are some issues with the way i have it written.  If i can't seem to make it work I will attach it and ask for help.  It has labels on most functions and no icons.  :)

Thanks again for your help Joseph.....

Permalink Reply by Joseph Oster on August 27, 2015 at 1:30pm

Here's one that:

• revolves the input curve to create a surface
• rotates the end point of the curve 90 degrees
• creates 'Curve On Surface (CrvSrf)' between the start and rotated end points.
• makes a polar array of 'CrvSrf'.
• adds 'Pipe' to the array of curves.

Attachments:

• barber_pipe_20150827b.gh, 11 KB

Permalink Reply by Carl Hill on August 27, 2015 at 2:24pm

Joseph.........that is exactly the objective.  Wow.  First, my tool choices and order were not good.  I was trying to create the pipes first rather than after i had the curves on the surface. 

Your picking up on this thread has been great....way beyond providing a solution.  You, combined with the way i was addressing the problem, have me approaching my learning differently.  One thing i am doing is creating a PowerPoint slide file of every object/component in GH.  That will provide me with a visual of what is there and what the Inputs/Outputs are for each.  Also, your help and solution will add to my own help file on where to begin a program and which components to use as the code is built. 

At this point GH is quite overwhelming.......

Thank You very much.

Carl

Permalink Reply by ng5 Alex on August 27, 2015 at 2:32pm

nice strategy. you can also create small definitions with notes in panels or with scribble component that deal with specific components or exercises.

best

alex

Permalink Reply by Joseph Oster on August 27, 2015 at 2:35pm

Glad to help.  GH is indeed overwhelming!  There is much more about it that I don't know than what I do.

I stick with "first principles", basic GH instead of plugins, though would use a plug-in if it did something I needed and couldn't do otherwise.

Simple solutions are the best, and GH can be profoundly spare and elegant.

Cheers

Permalink Reply by Carl Hill on September 2, 2015 at 1:37pm

Joseph........et. al.

After numerous issues with making some parts for my pens and then upgrading the OS on my milling machine i got back to GH this morning.  Here is a Screenshot of your inputs modified with my curve and a mirror command. In effect this creates a weave pattern on the surface.  Now to 3D print the file..... :)

One needs to think in different functions than Rhino to create the result desired.  I never would have thought of Closest Point on a Surface command.  Although GH runs in Rhino and has some commonalities, it is a different language. 

Wow........Thanks again......

Attachments:

• GH Bars on Pen tube.png, 1.2 MB