How to flip internal "edge" or fold of a polygon?

Hi everyone.

I’m sorry if this information has already been delivered many times, but I really could’nt find it. :slight_smile:
Maybe it’s due to not knowing the proper “word” to define it… anyways.

How do you “flip” the internal “edge” (sub-edge ? fold?) in a polygon, when the one decided by the app doesn’t follow the geometry as well as it could ?

Thanks in advance for your help :slight_smile:


Use images to help you explain, and prepare and upload an example .blend for troubleshooting every time your question involves one. That’s how you communicate effectively on a forum that is for visual arts - visually.

Also don’t put relevant words in quotes. Quoting indicates that you don’t mean the word(s) in them. Although even without that, the sentence leaves too much for interpretation of what you’re actually working with.


Hi @JA12

Thanks for your reply. I’m sorry for the quotes, I should have mentionned that english isn’t my native language. And as I’m still unsure of the terms to use… anyway, I understand your point.
And as you may have surely understood as well, I’m pretty new to Blender.

Regarding the visuals, here is a screenshot showcasing my problem:
On this Quad, you can see the center “line” or center “fold” going from point A to Point C.
I wanted to know if there’s a way to flip it from AC to BD, without having to convert to Tris and do it manually.
When using 3DSMax lots of years ago, I remember there was such an option, hence my question.

Thanks in advance.

The face is non-planar, and the triangulation happens automatically. There’s no way to have control over it without adding an actual edge on the fold. You could try triangulation modifier, triangulation tool, or mesh -> clean up -> split non-planar, that have options for how the triangulation happens.

Thanks again @JA12

Indeed, the last option, which creates triangles in addition to the Edge > Rotate Edges CW did the job.

Have a nice day!

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