Curves don't align or bend on mesh loop but works on Bezier curve

Support Modeling
1

Hi all,

I’m trying to create a basic ‘stitches’ geometry node setup from a couple of hacked together posts on reddit and a lot of guess work (I really have no idea what I’m doing with geometry nodes).

Anyway, I’ve sort of got it to half work.

stitches
stitches2560×1440 314 KB

If I apply the setup to a Bezier curve you can see I more or less get the result I wanted.

However, if I apply a minor modified setup (one that takes a vertex group as an edge loop to act as the curve), all I get are a bunch of straight lines at all sort of angles.

I guess not all curves are created equal, but I’ve got no idea how to fix it.

Here’s the blend file:
stiches1.blend (1.1 MB)

2

Its because Stitch Length was set to 0.
To alight it to mesh normals here is setup

image
image1497×911 216 KB

6 Likes
3

Thx, that seems to have sorted out the alignment, so that’s all good.

But for some reason, for me Stitch Length isn’t producing the result you are showing.

stitches2
stitches21920×1080 211 KB

In fact, unlike with the Bezier curve, it doesn’t matter what I set the length to, it has no affect at all.

This is with Blender 3.4.1, possible you are using 3.5 and something changed?

4

So I seem to have partly found what’s causing my issue, its the Randomize Thread Length group.

If I disconnect that, then I get stitches as expected (just not random variation), with it connected I just get lines. This seems to only apply to a mesh selection via vertex group, on the Bezier curve it works just fine.

5

Never mind, I adjusted a couple of nodes and think I have it all sorted out. Cheers.

6

Bit of a second question on this. Is it possible to get the same result without realizing the instances?

I tried playing around with it a bit, but without realizing instances, the curve that makes up each stitch just remains flat and loses all shape to it.

I mean it works as it is, but of course the vertex/face count really goes up as each stitch basically becomes an object, rather then making one stitch an object and then instancing that all around.