Empty space between line and fill

[ANTI_TWIN]

I created a circle shape with a black stroke and a black fill and there is a line of empty space between the stroke and fill that is obvious from any magnification. I've been working with Affinity Designer for a bit now and this bug only happens in some projects but once it does happen it happens for every circle drawn. Is there something that I need to do to stop this from happening?

[BofG]

10 minutes ago, ANTI_TWIN said:

Is there something that I need to do to stop this from happening?

Change the stroke alignment from "Outside" to either of the other options.

[R C-R]

It is hard to tell from the screenshot but looks sort of like the stroke & fill colors are not exactly the same shade of black.

[BofG]

5 minutes ago, R C-R said:

It is hard to tell from the screenshot but looks sort of like the stroke & fill colors are not exactly the same shade of black.

Try it. It is an issue with the way the anti-aliasing works. Shows on vector and pixel views plus exports that way to png (probably all raster formats).

[R C-R]

25 minutes ago, BofG said:

Try it.

I did, several times. As long as the stroke & fill color are exactly the same, I get no antialiasing, & it does not matter how the stroke is aligned. Tested on my iMac running Catalina with AD 1.10.9.

[BofG]

22 minutes ago, R C-R said:

I did

I tried on Windows, same colour on fill and stroke and get the exact same as the OPs image. I'm on v1.8.3 though, so maybe OP is also on an older version.

[R C-R]

Just now, BofG said:

I'm on v1.8.3 though...

If you don't mind my asking, why so old a version? There have been a lot of bug fixes & lots of new features added since 1.8!

[BofG]

Just now, R C-R said:

If you don't mind my asking, why so old a version? There have been a lot of bug fixes & lots of new features added since 1.8!

Short answer: it works, and I know it does.

Longer answer: The initial update to 1.8 had a severe bug with it being impossible to add an artboard to an existing document. I have some other software that I have to export pdf files to, the nuances of that mean I need to add an artboard and rotate it. The update meant I couldn't do any work - worse was I had purchased through the Windows Store and had no way back. Serif support told me I had to buy a new licence if I wanted to temporarily run an old version. Since I don't need the new features I've stopped at that release as the bugs it does have don't affect my work and I know for sure I can export the files the way I need them. I've kept an eye here on the new versions, and they still go out the door with bugs in that were identified in the betas, until the policy changes to only release when known bugs are fixed I'll be staying put.

[R C-R]

1 minute ago, BofG said:

Since I don't need the new features I've stopped at that release as the bugs it does have don't affect my work ...

But some bug(s) in that old version could cause the kind of things you are reporting here, for example with outside stroke alignment.

As for no way to go back, at least on Macs Time Machine or similar backups make that possible for Mac App Store buyers (& it is something Apple recommends for all users), but I do not know if there is anything similar for Windows.

[ANTI_TWIN]

I made this circle on the most updated version and yes both the fill and stroke color were the same. Yes the gap disappeared when I changed the stroke position however I think it's pretty undesirable to have an empty space with any of the three position settings.

[R C-R]

5 hours ago, ANTI_TWIN said:

... and yes both the fill and stroke color were the same.

Just curious at this point in the discussion but how specifically did you make sure the colors were exactly the same?

[BofG]

2 hours ago, R C-R said:

Just curious at this point in the discussion but how specifically did you make sure the colors were exactly the same?

Maybe you can post your .afdesign file so @ANTI_TWIN can see how you set it up to work.

[R C-R]

2 hours ago, BofG said:

Maybe you can post your .afdesign file so @ANTI_TWIN can see how you set it up to work.

same color stroke & fill.afdesign

Stroke is set to outside but changing it to either inside or centered makes no difference.

[ANTI_TWIN]

9 hours ago, R C-R said:

Just curious at this point in the discussion but how specifically did you make sure the colors were exactly the same?

I know the colors are the same as they were picked from the same color pallet tab. I know how to work around it but it is extra work that seems silly to have to do. I know that many other people seem to have similar problems. I have even overlapped two shape but upon zooming out a thin, but visible, empty line appears which leads me to believe this is a bug.

[BofG]

4 hours ago, ANTI_TWIN said:

I know the colors are the same as they were picked from the same color pallet tab. I know how to work around it but it is extra work that seems silly to have to do. I know that many other people seem to have similar problems. I have even overlapped two shape but upon zooming out a thin, but visible, empty line appears which leads me to believe this is a bug.

If the file provided above has the same issue when you view it then it has to be a bug related to your OS/version. There is a bug section on here where you can report it and it will get picked up by the staff.

[NotMyFault]

The thin line is probably caused by:

• circle and stroke are (correctly) handled as separate objects (required to have different colors etc)
• anti-aliasing is set to on 
• This correctly leads to edges with partial transparency. The alpha blend formula then leads to thin line with partial transparent pixels.

To better understand how this undesirable result is caused, just think of a circle and stroke is two completely separate objects: The inner circle, and the outer donut. Affinity only provides the comfort to automatically create them, and manipulate them via the UI. Currently Affinity has no option to automatically solve this issue for you, as it is strictly adheres to the basic standards. 

Possible mitigations / workarounds 

• Deactivate anti-aliasing for this layer (cog wheel / blend ranges)
• modify the sequence / order / size / alignment of strokes to ensure that there are always fully opaque pixels in the relevant area
• use an additional backfill circle with adequate size below your circle

 I know none of these workaround will make you happy. To solve this on app level affinity would need to introduce behavior that could break compatibility with other Apps and established standards (SVG, PDF):

• Adjust the size of the lower object (fill or stroke) by about 1 px to cover the former partial transparency. 
  this could be a user-selectable option per vector shape „fill partial transparent edge pixel if covered by adjacent object“
• Adjust anti-aliasing to work only on outer edge of fill - stroke. 
• Adjust anti-aliasing / blend formula to return 100% alpha for „connecting“ objects.

We might raise this as feature request.

 

 

Edited August 22, 2021 by NotMyFault

[BofG]

@NotMyFault are you on Mac or Windows? According to @R C-R this particular anti-aliasing quirk is a non issue on the latest Mac version, so if it's only present on Windows then it should be treated as a bug.

[NotMyFault]

I‘m on Windows and iPad, issue is present on both platforms.

This problem can bite you in every situation where anti-aliasing is used, e.g. having 2 objects with identical edge curvature aligned  to each other. If Affinity already found a solution for strokes on Mac, i would be interested what method they use.

[BofG]

8 minutes ago, NotMyFault said:

This problem can bite you in every situation where anti-aliasing is used

I'm certain it's not a general solution to the sometimes undesirable anti-aliasing. Maybe a special case tweak for stroked circles. Odd that it would only be on the Mac version, not Windows or iPad.

[NotMyFault]

I would like to ask a Mac user to export the attached file as SVG, PDF and PNG.

Please provide a screenshot of 400% zoomed using pixel view mode, showing the blue / red transition with anti-alised (blended) pixels.

Please inspect in exported PNG for  blended pixels with info panel, and check for green color. If present, issue is unsolved. (Below it is present, on iPad).

I would like to compare the results from Mac with Windows / iPad.

The green backfill makes it easier to spot than transparency.

iPad has no way to easy inspect pixels for transparency (getting numeric value). 

 

 

Stroke Gap.afdesign

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[NotMyFault]

@Lagarto

can you provide a PNG export from CS6, using my sample file.

Curious  which color blend it produces.

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[BofG]

33 minutes ago, Lagarto said:

UPDATE: I can reproduce the same issues with the file @R C-R posted above.

@R C-R can you double check? Export to png as well and zoom in on that boundary.

48 minutes ago, NotMyFault said:

Please inspect in exported PNG for  blended pixels with info panel

Different colours on fill/stroke will always AA, the assertion from @R C-R was that it didn't occur when fill colour = stroke colour.

I believe it does occur in all instances, proof so far is that it does and the only solution is to avoid outside stroke alignment.

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