Order of FX layers with rounded corners

[sPretzel]

I have come across an issue with rounded corners. I noticed a difference in the corner appearance if I swap the order of FX layers Round Corners and Offset Path. It appears that Round Corners as top layer and Offset Path as bottom layer is the configuration that preserves the original radius of the rounded corner (no visible bulging between the two). I realise that AI uses Bezier curves for circles but was not expecting an issue here.
Attached is a self-explanatory editable pdf attachment with four layers:
1- Path is directly offset (no FX), then rounded with FX. RED
2- Path is offset with FX, then rounded with FX. YELLOW
3- Path is rounded with FX, then offset with FX. GREEN -- offset path that looks correct to me with respect to original path.
4- Path is rounded with FX. No offset. ORANGE -- original path that I want to offset.

Zoom in on a corner and turn on/off a layer to compare.

Does AI apply FX from top layer to bottom layer?

I'm sure Monika will love this!  😄

[Monika Gause]

The round corners effect sucks. Are you still using it because CS4?

As for the Appearances, yes, they are applied from top of the panel to bottom. But the strokes and fills are stacked from bottom to top. Effects below them, get applied after them.

[sPretzel]

Hi Monika,

No, I just continue to use CS4 because it does most of what I need and CC is pretty expensive. I don't have any other option in CS4 to round corners (either directly when creating the object or through FX but the result is the same, I believe - I can't remember). Is there an alternative to rounded corners FX in CC?

In the file, I put all the FX above the fill and stroke but the order makes a difference of the FX themselves makes a difference. Do you agree with the fact that #3 looks like the correct version of #4 with offset path? (path is offset by half the stroke size)

[Monika Gause]

You could use a script for rounding corners.

If you had bought a licence of Astute Graphics VectorScribe in time then you would have had a better corner rounding effect, but they aren't selling that version anymore.

I don't really see why you put Offset path into the equation. What is the goal?

[sPretzel]

You've got an eye for detail. The short answer is that I'm looking for trouble (which I often get into with Adobe). The actual reason is that I offset the path instead of using inside or outside for the stroke. It preserves the stroke when exporting to pdf.

[Monika Gause]

I don't think I understand your workflow.

[sPretzel]

Don't worry about it. This aspect is irrelevant to the issue being discussed in this post.

[Monika Gause]

Offset path can be very helpful in situations where you in reality do not want to offset anything. So if it helps you when you do this in any particular order, then I would just go with it, but make sure to document it in the file why the effects are in that particular order.

[sPretzel]

Offset path can be very helpful in situations where you in reality do not want to offset anything.

By @Monika Gause

Now I'm not following you! What? Why use offset path FX to offset nothing?

You forgot to answer my question: "Do you agree with the fact that #3 looks like the correct version of #4 with offset path? (path is offset by half the stroke size)"

[Monika Gause]

Sorry for not answering your question - I am really lost in all those lines. 

As for the offset path: https://youtu.be/2ZrDpcIhLo8

In a couple of weeks I'll be publishing another video where offset path helps with an unrelated problem.

[sPretzel]

Hi Monika,

Have you been working on your channel or what? I don't remember it being like that. Or did you add thumbnails? It looks great! I will have to catch up on your videos as I know you go to the deep end of Illustrator.

I watched the video (you put twice the same link). It's not related at all to the purpose I used offset path in this thread (which has to do with Acrobat), which itself is not relevant to the question in the original post. Follow me?  😉   That being said, what an interesting effect. Some effects like this, I could never do by reading the Illustrator manual/online help. I could only get to them either by chance, by mistake, or by watching someone else do it. Or explain it, which leads me to "you could add a voiceover and a more explicit title".

Once again, I learnt something from you. Thanks Monika.

[Monika Gause]

Thank you!

That particular video was just an answer to a Reddit post. I do not record those with audio. But it's in my pipeline of videos "to be recorded". I know that the particular usecase has nothing to do with yours. I just wanted to point out a usecase where offset path does not offset paths.