Lofting arc to arc


(Daniel J Thompson29) #1

Hi, I have a tower that I have created the outline for the panel. I ahve worked my way through using the knowledge I know and managed to make every other pair of arcs loft (leaving a par of arcs void between them). Is there a way to have the gaps become surfaces too. Simply first arc lofts to second arc, second arc doesn’t loft to third arc but third arc does loft to fourth arc and so on. I would like first arc to loft to second arc, second arc to loft to third arc and third arc to loft to fourth arc etc. etc. These would be individual surfaces that share an edge with the previous and next surface. I have attached the GH file and Rhino File for ease.

There are 2 optional elements I would like to be able to control but aren’t essential (as I can make do) but would like if possible.

  1. Can the tangent of the arc be made adjustable so that the curve is not half circular but less.
  2. The top and bottom edges are squared, is their anyway they can be curved to match the segment of spiral between the respective arcs?

Any thoughts would be appreciated.

Parametric Tower 2.3dm (205.9 KB)

Workflow (9.8 KB)


Creating equal panels on a curved surface with tapering corkscrew
#2 (13.8 KB)

#3 (18.9 KB)

The last one at the top fails because you used DivLength so there are no points at the top end of the curves, therefore no “rail” curve there for Swp2.

(Daniel J Thompson29) #4

Thank you so much, why is Swp2 red? or is that just a glitch?


See amended previous reply for explanation. (DivLength).


Here is a fix for that problem. I also fixed a different subtle problem by using the re-constructed horizontal vector for the axis of the second VRot component. (21.2 KB)

Why does Swp2 stll fail? Well, that’s complicated… but here is a fix for that. Can you see it? The Short (Shortest List) component before Entwine, with Shift W (wrap) set to false. (20.9 KB)


Wait, so this thread is a duplicate of an earlier thread, but different somehow? So sorry I didn’t realize that earlier.

I looked at the other thread yesterday(?) but don’t really know what’s going on there? Maybe asking that the tangent ‘Angle’ slider in this code (blue group) decrease as a function of height? In any case, I’ve added the ability to rotate the “panels” in this thread on their centerlines, ±90 degrees, and reduced ‘max length’ from 10,000 to 2,000 to make the “panels” narrower. Dimensions of this model are absurdly HUGE??? The full spiral curve length is 1.13854e+6. WOW! (25.9 KB)


This version adds that capability in the cyan group. The split screen shows the ‘bot tan angle’ (bottom = 20 degrees from horizontal) on the left and '‘top tan angle’ (top = 60 degrees) on the right. Everything in between is proportional to ‘Z’. (25.1 KB)

Creating equal panels on a curved surface with tapering corkscrew