# Loft problem

Hi,

I am converting an open brep into a surface.
Extracted contours and points.

So far so good. My loft is looking very strange.

I need it to be mapped with a geometry.

I also tried surface from points and networked surface with no success.

Any hints?

Best regards,
SFS

1809_brep-surface.gh (22.4 KB)
1809_brep-surface.3dm (93.5 KB)

Baking the GH-curves and then lofting in Rhino makes a perfect shape.
In GH the curves are unsorted, the loft jumps from the 5th to 3rd… How do I make GH understand which curve is the first one?

You can avoid generating a polysurface frSweep1 by using Fit Curve.

1809_brep-surface_re.gh (22.0 KB)

3 Likes

hi,
First off, It is best to internalize your geometry so as not to have to post both .3dm and .gh file (have a read at this, it’s going to be very useful)

What I think the problem is, is that the result of your loft is not a surface as you might think. (if during a loft it is difficult to connect a series of curves, Grasshopper creates a brep -so as to give you something- but it is essentially a mesh and doesn’t have the properties of a surface.)
In the following definition I realigned the ‘ribs’ using orient and the result is indeed a surface.
surface.gh (19.3 KB)

EDIT:
Sorry, I missed the scaling part (I always miss something )
surface.gh (20.8 KB)

2 Likes

Fit Curve is the under appreciated hero of Grasshopper to be honest

1 Like

Awesome!
FitCurve is great, I haven’t used that component so often.
It solves everything!
Thanks for the fast reply HS_Kim.

This example is very useful for working with geometry that was created in other software!

Best regards,
SFS

Hi anikolo,

of course I know internlalize data. In this case it’s about getting geometry from the outside, so I use it for tests and import Iges-files.

Great solution, thanks!
The one you did is a different setup, which is also very nice.
I want to focus on imported geometry here though, but I could extract a central curve and do what you suggest, since it is very clean and nice. But the geometry can be assymetrical too, which makes everyhing different I assume. Gonna run some tests…

Thanks!
Best regards,
SFS

@Michael_Pryor you can add in `Pufferfish` a fit curve component with an angle input.
https://developer.rhino3d.com/api/RhinoCommon/html/M_Rhino_Geometry_Curve_Fit.htm

2 Likes

Sure I can toss it in. I have also a cool one in the next version that fits only certain segments of curves based on the degree you specify.

1 Like

I added Fit Curve Smooth and Fit Curve Segments to the new Pufferfish V2.2

1 Like