Loft in rhinoscriptsyntax

Rhino Developer
, ,
1

I’m trying to make a script that lofts 2 closed curves. One in an “irregular circle” (it’s a circle when looking from the top plane, but the 3d geometry is irregular) and the other one is just a bigger concentric circle.

I’m trying to do it with just rhinoscriptsyntax.

The loft works great when done manually but when I try doing with a script I end up with the monstrosity below:

image
image1267×514 131 KB

What I’ve already tried:

  • Using points to guide the loft
  • Changing the curve directions to match
  • Using the sweep2 instead of a loft (couldn’t even get that to work)
    None of the above worked for me.

Here’s the code:
tryingToLoft.py (721 Bytes)

import rhinoscriptsyntax as rs

baseCurves = rs.SelectedObjects()
for curve in baseCurves:
if rs.IsCircle(curve):
smoothCircle = curve
else:
perimeter = curve

sameDirection = rs.CurveDirectionsMatch(perimeter, smoothCircle)
if not sameDirection:
smoothCircle = rs.ReverseCurve(smoothCircle)

closestPoints = rs.CurveClosestObject(perimeter, smoothCircle)
sweepLine = rs.AddLine(closestPoints[1], closestPoints[2])
rs.AddLoftSrf([perimeter, smoothCircle], closestPoints[1], closestPoints[2], 3, 1, 100)

#rs.AddLoftSrf([perimeter, smoothCircle]), None, None, 3, 1, 100)
#rs.AddSweep2([perimeter, smoothCircle], sweepLine, True)

I’m also attaching the file with the 2 curves if anyone wants to give it a try. You need to select the curves first before running the script.
2 closed curves.3dm (94.9 KB)

Any help is appreciated

2

hi @robneto.eng see if this helps (no error checking):

import rhinoscriptsyntax as rs
import scriptcontext as sc
import Rhino
from Rhino.Geometry import *

curves = rs.SelectedObjects()
crvs = [rs.coercecurve(c) for c in curves]

start = crvs[0].PointAtStart
_, cp = crvs[1].ClosestPoint(start)
pt = crvs[1].PointAt(cp)
crvs[1].ChangeClosedCurveSeam(cp)

loft = Brep.CreateFromLoftRebuild(crvs, Point3d.Unset, Point3d.Unset, LoftType.Normal, False, 100)[0]
sc.doc.Objects.AddBrep(loft)
1 Like
3

It does work, thanks!

But I can see you’re using rhino.geometry to create the loft. Any idea why it doesn’t work with rhinoscriptsyntax?

4

The only way to make this work is to modify one of the curve’s seam

5

Just tried that and got same results. Now I’m wondering if rhinoscriptsyntax loft is just bugging out.