Find out in which direction surfaces' uv-orientation is switched

Rhino Developer
1

Hi there,

I came across a strange observation.
In the screenshots you can see two surfaces, which are part of a multi-face brep.
I just indicated the adjacent faces and did not show them, to be clearer in the presentation.

So my aim is to re-orient the unrolled brep to the original brep with a reference to this surface.
I thought I’d achieve this by the surfaces properties, but somehow it seems to change when unfolding.

OrientationIsReversed helps a lot to find out if there are changes.
As you can see the switching happens in whatever direction and I cannot really control this.
The question I ask myself now is: Is it possible to find out which direction is the switched one?
Otherwise I would consider myself as screwed…
Or is anyone aware of other options to reorient this?

Thanks,T.

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1 Like
2

I think I was in a similar situation before trying to orient text on unrolled breps. I ended up unrolling lines which would then be used to align planes…

3

@martinsiegrist nice approach, thank you.
It only will get a bit messy when already having curves that are going to be unrolled as well…

4

Sure thing. I’m doing this in Grasshopper and my easy fix is to use two separate scripts so I don’t need to worry about the data structure too much

5

@martinsiegrist, you mean that you do the unroll twice, right?
Once with the leading curve only and then with the rest…

6

Yes. Using the following script in Grasshopper twice.

unroll_c.gh (28.2 KB)

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