#3StrandBraids #FlowOnSurface
In the top-left, the highlighted magenta portion shows the interface between the
#braids assembly and the
#IonicScroll from
https://pixelfed.social/p/Splines/795276076797088402.
Extract the
#profileCurve shown as ABC in the top-right where the interface meets the scroll.
In
https://pixelfed.social/p/Splines/794199123072358090, we rebuilt curves from 2nd-degree arcs to 3rd-degree NURBS for smoothness and swept the scroll surface one set of arcs at a time.
Now we have to flow braids on a single surface in one operation. So we need to combine the separate segments into a single NURBS curve. To do that,
#explode the profile curve into individual segments, discard the straight portion, and join the curved portions.
Curves and surfaces have a
#direction that you can change in the
#CAD tool. Check that the direction of the joined curve is A to C, not C to A, and flip it if necessary. Then divide the curve at 120 units starting at A. This is marked by point B. Split the curve AC at B so that AB is 120 units long.
At this point AB is still made up of 5 segments, and exploding it would again decompose the curve into separate segments. So
#rebuild AB as a single NURBS curve with 32 sections.
#Extrude AB to get a 48 units wide surface shown in magenta in the top-right. Point D is at the midpoint of AE and lies on the XZ plane.
Slice the channel assembly so that it is 8 units tall, 6 of which will be above the
#tectonicSurface for the braid and 2 below. The tectonic surface is shown in the bottom-left as the flat magenta surface on the channel and the curved magenta surface for the scroll neck.
Flow the entire braid and channel assembly along the curved surface lining up points A, D, and E. For the vertical part on the side of the capital, just use the 33 unit tall block from
https://pixelfed.social/p/Splines/799340150182400358 and bury 1 unit inside the
#ovolo.
This concludes 3-strand braids. Only the non-essential
#column #flutes remain.