Solid from curves

Hi everyone,

There are some curves in this .3dm file.
I’m trying to generate a solid model from them using grasshopper.
TEST-CURVE.3dm (58.9 KB)

But it’s so hard, you know.
I always fight with a seam line, like this guy.

Especially, meshes will be so terrible with this seam line, processed with finite element analysis.

So is it possible to generate a solid model from these curves, like sweptblend in revit.
image

Thank you.

KR
Thomson

Hi @Thomson,

I used here the x position to extract, as starting point for the curves.

adjust seams.gh (6.0 KB)

1 Like

Hi @Erik_Beeren,

There are some seam lines maybe…
I’m confused about these things, which leads to my mesh model like below photos…

KR
Thomson

You have some seam of them because a continuous curve is made with 2 curves or more. Rebuild your curves and it will be better.

Em… :thinking:, I’ve tried to rebuild it with JoinCurves. It just doesn’t work…
Could you give me some suggestions to rebuild it, thanks.

KR
Thomson

I don’t know if there is an automatic tool, but I think JoinCurves will just put the curves in a sort of list. Curves that are not tangent will not be build in one single curve.
You could do that by using
image
Try to add always the same number of points at regular distance. If not you could then rebuild the curve with a rebuild command.
Here the blue cross represent start/end of curves. You can see that there is a point at middle positions on the curves on the left. That is not good to generate nice surfaces. On the right there is a point just at the kinks/corner.


Control points there

From the many discussion on class A surfacing … I think one of first rule is to have nice and low control point curves.
TEST-CURVE.3dm (416.7 KB)

Awesome :clap:!

Could you give some suggestions about rebuilding it using grasshopper, please.
I tried Divide Curve and Interpolate, and there are still two curves in grasshopper.

KR
Thomson

There is Fit curve in Rhino
https://docs.mcneel.com/rhino/7/help/en-us/index.htm#commands/fitcrv.htm

There is Fit curve in Grasshopper but it seems the angle tolerance is not set. You should look to another plugin that has all the options.
But it is easy to code
image
0.1 is the tolerance, use a tolerance that is related to you project
0.1 is the angle in radians

Still some bad curves

First time I use this component and method. Never too late to learn.
curve fit.gh (19.3 KB)

Hi @Thomson,

I do not know where you need the mesh for. But you could use the triRemesh component.


adjust seams.gh (17.6 KB)

1 Like

I think he is remeshing with Tetrahedron with Gmesh. So he is surely using a step on an iges

Hi, @Erik_Beeren
It’s a really beautiful mesh :+1:. I’m trying to mesh a solid model in the preprocess tool for FEM model.
So, maybe a solid model is more suitable.

KR
Thomson

Emm, when I loft these curves, there are still some troubles :face_with_monocle:.
image

I think the interpolate curve may work.
But it definitely failed…
MYTEST.gh (11.7 KB)
image

KR
Thomson

If it is not a repetitive task I advise you to build the curve and loft with Rhinoceros. You will have a full control of the seam position and orientation. The 3dm I posted above was done in Rhinoceros.

Hi @laurent_delrieu ,

You’re right. The method you mentioned above is really nice.
In fact, I’m processing a more complicated model than this one.
It’s so hard to deal with it manually, so grasshopper is a better choice to me, maybe.

KR
Thomson

It is hard to advise you correctly as some tools are not working well or I don’t know the trick to make them work. There are many strategies workaround to solve a problem and take into account the good and the bad of a tool. I don’t know why fit is not working.
Here a script that works with your curve.
I reuse @Erik_Beeren tool to adjust seam.
Seam is using X axis to sort seam, it will not work every time
I use my Fit component as the GH component is for some reason not useful there.
I use also an orient tool from Sasquatch.


adjust seams LD.gh (20.6 KB)

Ps : Fit was not working for one curve because the seam was on the middle of a curve.

2 Likes

It’s amazing :partying_face:!

Thank you all, guys.

KR
Thomson