I want to fix the second side of a SubD by mirroring faces from the other side. When I do this, the inside faces of the original side become the outside faces of the second side. [InsideOutFaces]

Looks like Flip fixes this for me. But it seems like this shouldn’t happen?

Hi Mitch, You’re correct, a mirrored face should not have it’s normal flipped. I am not seeing this issue here though to file it as a bug. Can you post the 3dm?

Here you go Mirror Flip Normal.3dm (2.4 MB)

I had been extracting the faces first and then mirroring which doesn’t make this happen. If I sub-object select the faces and then mirror, I see what you reported… filed as https://mcneel.myjetbrains.com/youtrack/issue/RH-60826 Thanks.

When I use mirror to copy some faces, the inside becomes the outside

Rhino SubD

brian (Brian Gillespie) October 7, 2020, 9:02pm 6

RH-60826 is fixed in the latest BETA

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When I use mirror to copy some faces, the inside becomes the outside

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