Celtic Weave question

[gdonnelly]

I created the following design using the Celtic Weave Creator (see Celtic Weave 1). The highlighted yellow parts show curved areas where the surface of the weave appears "folded over" rather than rendered smoothly (see enlargement Celtic Weave 2).

What am I doing wrong? Of course, I'd like these areas to be smooth (not folded) at these turns (see Celtic Weave 3.jpg).

Thanks,
Gerald

[CarveOne]

I had that happen on one of my early extruded weave attempts. If there is a node at the points where that happens, try moving the node away from it and see if that clears it up for you. It did in my Celtic Cross extruded weave project.

CarveOne

[gdonnelly]

So, here's where the nodes are on one of the vectors (see attachment). I don't know how I can move the nodes from those problematic locations without fundamentally changing the shape of the design. Any thoughts?

[gdonnelly]

Another way of asking my question is this: "Is there a way to use the Celtic Weave Design widget create this object (see attachment) without the "folding" artifacts I've illustrated in my original design"?

[darde]

Could the fact that your ends change width and don't match the rest cause a problem?

[gdonnelly]

I'm not sure. I see what you mean, but I didn't change the widths...all I did was create a "cross section" vector and selected it while using the Celtic Weave Widget. IF the width changed, it was caused by the widget.

[Adrian]

Tried a few times to replicate what you're seeing with a similar shape and it comes out perfectly every time. Could you post the actual file or show the settings you used with the Single rail sweep?

[gdonnelly]

I created a new weave pattern to see if it also created the curve "folding". Here's what I got.

Celtic Weave Widget.crv3d

(1.86 MiB) Downloaded 236 times

[CarveOne]

I recreated the first example, making the width equal all around the knot. Folds are still there.

Node editing won't help with this particular problem.

I changed the shape vector to an ellipse and removed the lower half, the folds are gone and perfect 45 degree rounded creases are there.

I made a flat top shape with 10 degree angles on the "legs" and the folds are back.

I made a flat top shape with 45 degree angles on the "legs" and the folds are still there.

It appears that the extrude tool just isn't smoothing the 90 degree inside corners correctly for most shape vectors. Until it is corrected in a future update some manual smoothing of the model or hand sanding are the two options.

CarveOne

[gdonnelly]

Thanks for all your time/efforts to test out options!

[CarveOne]

I saw it right after I got the v4 upgrade while playing with the extrude weave tool and finally decided to take a stab at trying to see if the shape vector would affect it.

Maybe the programmers at Vectric will investigate it and fix it, or at least explain why it happens and how to avoid it. Hope so.

CarveOne

[sawmiller]

maybe if you cut one of the points off, then rejoined it with the tool that extends the line
could do this on one end and check it out
i say this cause that single rail sweep is not supposed to be good at corners that are curved

[gdonnelly]

Sorry, Sawmiller, I'm very visual and so I'd have to see a picture of what you're suggesting.

[gdonnelly]

Also, sawmiller, the Celtic Weave Widget may be, indeed, the "rail sweep", but Celtic Weaves are, by definition, curved... so why would the Widget not be designed to work with curves!!!???

[BrianM]

Hi,

The Weave creator is pretty clever, but there are limits to what it can do. The square sections you are extruding are pretty wide relative to the vectors you are extruding along and the impact of trying to 'mitre' the corners is extending back along the drive curve past the spans which actually form the corner. For a square cross section this will lead to the issues you see. If the section was rounded - which is the traditional shape for dimensional celtic weaves, this effect will usually not be as noticeable. As you have mentioned the sculpting tools can sort this out pretty easily and is still far easier than trying to create these weaves by any other method I'm aware of.

Brian