Stroke Profiles Flipping When Flipping Object.

[BecJM]

How do you stop stroke profiles from flipping the wrong direction when you flip the full object, without expanding them? 

I've taken a bit of a screen record which I can't post here - you can view it on my Twitter:  https://twitter.com/RebeccaMills/status/1435476441261477891?s=20 

[tromboniator · Accepted solution]

What you are seeing is the expected behavior. You are reversing the path direction, so if the profile puts the whole stroke to the left side in the original path, it will stay on the left in the flipped path. The left is outside of the curve in the original but flips to the inside when reversed. You can reverse it in the Stroke panel or the Properties panel.

Peter

[Ton Frederiks]

Peter is right. Try Object > Path > Reverse Path Direction to see the same happening.

[BecJM]

Thanks Peter, I appreciate your response!

The flipping stroke direction makes sense.. but why does a stroke profile which is displayed as bulging upwards, bulges down when flipped. I'm interested if there are any users that would want it to behave like that?

To avoid this from happening, is there a way to stop path direction swapping when flipping? 

Is there any other option other than expanding or manually flipping profiles back afterwards? 

[tromboniator]

I'm not quite sure how else to explain this. An asymmetrical profile will always bulge on the same side of the line's direction of travel regardless of what that direction is or what the shape of the line is. If the bulge is to the left, then a north-pointing path will have the bulge to the west. A south-pointing line will bulge east.  The direction of your original path is roughly east, so the left side, where the profile bulge is, is north (or up). Flip the path so it points west and the left side is south, so the bulge is down. I hope this makes sense to you.

[Monika Gause]

You could flip it using the transform effect.

But when expanding the appearance, the stroke will be outlined as well.

[Kurt Gold]

Respect, Peter.

Explanations with all main cardinal points are certainly remarkable feats.

[tromboniator]

Thank you, Kurt.