I am trying to sweep this rectangle sections across these lines. I tried to make another rectangle on top so it would be easier but it did not work. How would I get this to work?
sweep probelms.gh (89.3 KB)
1- You connected the rail curve also on the section input… ?
Let’s ignore this. It’s just wrong.
2- Your datatrees are not matching, start and end section curves and rails have different order/sequence.
Only the end section is correct. Let’s ignore the start sections.
3- Sweep1 component can accept a List of section curves for each rail.
It uses the first section as it is from the start of the rail curve (and the last section as it is on the end of the curve).
You can fix this by flipping the rail curve.
4- Sweep1 expect the section start point to fall on the start of the rail curve. (debatable “bug”)
You can fix this with Closest Point and Seam components.
sweep probelms.gh (86.8 KB)
If your rail curves are straight lines, and you have both start and end sections, why not just use loft?
Sort your start and end sections to have the same order/sequence datatree and use loft, more reliable and simple.
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It worked for one set but I am having trouble with this next set. I am new to grasshopper so I don’t really understand the full extent of data structures yet
sweep probelms p2.gh (56.7 KB)
the elements on you first parameter go clockwise (top down), but the element of the second parameter go counter-clockwise (top-down).
It is possible to fix this by flattening, partitioning (with proper amount), reverse list, flatten again.
But this solution won’t adapt to other inputs.
You are mis-managing whatever is before what you are attaching in the .gh file here.
Also, one parameter have a {;} structure, the other just {*} … different datatree structure depth.
This file provides more context
sweep probelms p3.gh (136.6 KB)
I understand the issue, but again I tried to fix it with no avail. sorry for my incompetence 
Dear Zarif,
Try to build your logic, step by step. What happened now:
- your create many lines in a rather logical way → OK
- you want to get a rectangular sweep around them. And made them in a simular way. And there you get lost in what belongs to what, etc
So one step back:
- Create 1 rectangle just basic on the XY Plane
- On every line create a Plane (perp frame)
Then orient the rectangle to all the lines.
Sweep 1 → Check if this is what you want?
Some tips: - Study how components are used. (here the reparameterize !)
- If you have 334 items and you want to work on them, do not flatten parts, what have to stay connected to those items (that will break the connection).
sweep probelms p3_EW.gh (28.0 KB)