# Lofting between edges

zeffii recently provided a nice demonstration of using Sverchok to loft between edges (Sweep along a path through multiple cross-sections).

I was wondering whether it would be possible to extend this functionality to provide more control about how the loft interacts with each edge .

Here's an example of what I'm talking about...

Using a simple array of vertically-stacked, similar rectangles, I've constructed a series of loft objects (vases, I think), demonstrating some of the different ways the curve of the loft might meet each edge it comes across.

I trust the image is self explanatory, but I'm happy to (try to) elaborate if necessary.

• We (Sverchok 2020, Feb) have no single node that encapsulates this behavior. But it touches a topic that I find interesting, the problem is only really; "How does one offer a convenient way to the user to tell that node how to interpolate between the various Quads". (Quad could be any Ngon ofcourse..) . We could initially offer a set of standard options as you list in the annotations to those images. Commented Feb 4, 2020 at 10:38
• Looks like a job for curves, taper, or maybe re-written nurbs? Would be nice to generate a taper control object based upon the number and relative distances of the cross sections. You might even make a taper control for each side or vertex / edge through multiple cross sections? Can Sverchok handle curves and taper objects? Commented Feb 4, 2020 at 19:32
• I'm learning that questions like that are like a red rag to a bull, so keep them coming (yes I'm aware that bulls are colour blind) Commented Feb 4, 2020 at 20:13

A current "lazy" approach to this. might be:

I use a few VD nodes here to emphasize the original Quad outlines (light blue), and the resulting interpolated outer edge (red). Note that the Plane (Mesh) Object has a Vertex order which is [0, 1, 3, 2], and we need both Verts and Edges to order the vertices (using Vector Sort) for the "connected" algorithm to get [0, 1, 2, 3].

The Smooth Lines node offers "Weights" input. When using the slider all verts are treated the same, but you can pass it a list of values (ranging from 0 to 1) to effect vertices uniquely.

I feel perhaps that this does not provide a full solution to your question, but sometimes even a partial answer can be useful.

• Well that's basically genius. Commented Feb 4, 2020 at 11:22
• You answered that one so quick, now I'm wondering whether to give you something else to ponder upon... Commented Feb 4, 2020 at 11:35