lofting multiple curve sets

just starting out with GH and i have a question about lofting multiple curve sets. i have populated a surface with a grid of circles, and then offset each circle. i would like to then loft each pair of curves, but i can't figure out how to separate them into pairs since 'loft' just takes a list, as opposed to 'curve a' , 'curve b', and so on.
any advice would be appreciated!
matt

Replies to This Discussion

Permalink Reply by David Rutten on November 23, 2009 at 10:57am

Hi Matthew,

you need to put your circles into lists before calling the Loft component. You can start by Grafting your circles (to make sure each circle is in its own little list), then offset them. Since it's possible that a single curve offset will output multiple curves as the solution, the output of the Offset component (if that's what you're using) will have a different (more complicated) data layout than the input. You need to make sure these two data sets are matched up again. Once you have two data sets of curves, one containing all the "A" curves and the other containing all the "B" curves, you can feed them both into Loft and it should work.

I'll post a screenshot of this in a minute.

--
David Rutten
david@mcneel.com
Poprad, Slovakia

Permalink Reply by David Rutten on November 23, 2009 at 11:23am

Using Offset will make this a lot more intricate than a method which won't modify the tree layout, such as Scale, Move etc..

Files attached. (You need 0.6.0043 to open it)

--
David Rutten
david@mcneel.com
Poprad, Slovakia

Attachments:

CircleLofts.ghx, 192 KB
surface.3dm, 111 KB

Permalink Reply by matthew pierce on November 24, 2009 at 1:39am

thanks to both of you for the rapid responses. i applied david's flatten and graft sequence and it appears to be working. i'll test it in a few more ways and then post the result.
thank you again!
-matt

Permalink Reply by alejandro on April 6, 2013 at 11:50pm

can't seem to save this file. i was hoping to reuse it for my lofting problem

Permalink Reply by Tilerman on July 27, 2014 at 2:58pm

Hi David, I think I have a pretty similar issue. I am new with Grasshopper, despite this I am trying to reproduce a very nice livecomponents-ny.com hexagonal patterned surface (http://livecomponents-ny.com/?p=633), very popular. I think I succeeded in creating the two surfaces, one having the original hexagol pattern, the other one, an offset of the previous one, having the same pattern scaled according to an attractor. My problem is I cannot loft each hexagon of the origin surface with the corresponding scaled one of the offset surface. I cannot understand the reason, I am not yet in grasshopper mood, could you help me, please?

Attachments:

Permalink Reply by Theunis du Toit on November 23, 2009 at 10:58am

an image of the definition would be appreciated with a Parameter viewer plugged into the component that will feed the curves into the loft component

Permalink Reply by matthew pierce on November 24, 2009 at 2:14am

ok, so here is my result attached. worked out perfectly!
another small item i need to resolve that i imagine is quite common- is there a way to exclude the points that occur at the surface edges? as you can see, the circles that are placed here are half on, half off.
i previously laid out the circles using a panelized surface which avoided this problem, but the distributing frames over the surface seemed like far fewer steps.
thank you again!

Attachments:

loft circles GH tree.jpg, 78 KB
surface image.jpg, 72 KB

Permalink Reply by Theunis du Toit on November 24, 2009 at 4:31am

I checked which objects intersect with the surface's edges and selected the other ones.

Attachments:

Grasshopper.jpg, 70 KB

Permalink Reply by matthew pierce on November 24, 2009 at 6:39am

i think what i need to do is eliminate the points that fall on the edge of the surface and then use the remaining points to create the circles, lofts, and holes that are cut in the surface by the projected circles. that will reduce the number of lofts, etc from the beginning.
any suggestings for that?
thanks,
matt

Permalink Reply by Theunis du Toit on November 24, 2009 at 7:24am

I think the game stays the same, only the players need to change. Replace the Brep parameter with the Points you will use to make the Breps, and change the intersection component with one that deals with planes(planes from the Points) and curves, not Breps and Curves. Thats all. Hope it makes sense.

Permalink Reply by Theunis du Toit on November 24, 2009 at 7:37am

Alright, planes are messy, rather create random curves from the points, then intersect the curves with the curves. I added an image with the definition.

Attachments: