Voronoi texture inconsistent over curve?

Question

Basically what i have here are three curves with an object bevel that i wanted to have this embroidery—stitching look to them with the stitching going perpendicular to the curve. I found a yt tutorial that used a texture coordinate, mapping node and voronoi texture and whereas the tutorial's result was a nice uniform "thread" texture, mine appears to be inconsistent when comparing the straight and curved segments of the curves.

Not sure if it has to do something with the proximity of the anchor points themselves, the handle/spline type, or the texture coordinate, but all help would be greatly appreciated.

Answer 1

Unless someone has come across a setting I haven't discovered, the default UV of a curve is measured by the sampling between control points, not by approximated length. This seems undesirable to me, but the way it is.

If you control-points are fewer, and more evenly distributed,as below,

... the anomaly is less evident:

Above, there are 2 examples. The top one, in each frame, uses the default UV, like yours, but with the curve constructed as shown at the beginning of this post. The bottom one in each frame uses a Geometry Nodes modifier to construct the mesh, and feeds the 0-1 Factors (which are based in length,) of the curves used to build the mesh on to the shader, to be used as UV.

There's very little difference between them in this manicured example, but the GN version is immune to unevenly distributed control-points.

Some variation of the group may help you out.

This post doesn't cover the difficulty with mapping the UV's of cyclic curves in Geometry Nodes, which is nicely covered by @quellenform , for example, here