bugFree UCS Outline Fonts - Bugs: bug #44233, Ligature tie positioned badly for...


bug #44233: Ligature tie positioned badly for some IPA combinations

Submitted by:  Hsing-yen He <hammerandsickle>
Submitted on:  Thu 12 Feb 2015 06:29:36 PM UTC  
Category:  individual character(s) Severity:  3 - Normal
Item Group:  letter positioning poor Status:  Proceeding
Privacy:  Public Assigned to:  Steve White <Stevan_White>
Open/Closed:  Open Release:  2012-05-03

Add a New Comment(Rich Markup)

You are not logged in

Please log in, so followups can be emailed to you.


( Jump to the original submission)

Thu 13 Apr 2017 08:50:51 AM UTC, comment #13:

OK I've gotten rid of the mark anchors to the preceding character, and instead placed all these diacritics to the top of the bounding box (and the low diacritics likewise to the bottom of the bounding box.)

The extreme example ʗ̃͡ʔ still crashes. The only conceivable solution would be a contextual positoning. I would not undertake that without fully understanding the scope of the project.

(We're talking about U+035C-62 -- and don't forget U+1DFC.)

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Thu 13 Apr 2017 08:13:41 AM UTC, comment #12:

Hi David,

On further experimentation and reflection, I removed the 'mark' positioning on the double-width high diacritics, opting instead to just place them very high.

For the problem of placing a mark above two letters of different heights, the only mechanism OpenType has to offer is contextual positioning. But if you add to that further marks over the individual letters -- it has gotten out of hand, practically.

I made one concession to your case of ʗ̃͡ʔ by putting a 'mkmk' on the double-width mark, but as I was doing it, I thought this will cause a problem in other cases, and sure enough ... that causes a collision in ɪ̈͡β̞.

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Wed 12 Apr 2017 10:51:48 PM UTC, comment #11:

OK I made some improvements, I hope, to Mono and Serif.
Some changes didn't take, somehow, in Mono.
Sans will have to wait for now.

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Wed 12 Apr 2017 06:28:10 PM UTC, comment #10:

U+0361 COMBINING DOUBLE INVERTED BREVE is used in the IPA, the ALA-LC romanization of Cyrillic, and the transliteration of bind runes, among other things. There’s basically no limit to the possible combinations. Making it work with all combinations of IPA characters with IPA diacritics should suffice. Since that is a lot to ask, I got a few dozen examples of U+0361 from Wikipedia and checked them in FreeFont. Most sequences like fine, but in some of them the inverted breve overlaps one of the other characters.

FreeMono: ʈ͡ɽ̝̊
FreeMono Bold: ʈ͡ɽ̝̊
FreeMono Oblique: b͡β e̞͡β̞ i͡β̞ j͡β̞ k͡ʟ̝̊ ɘ͡β̞ ɛ̝͡β̞ ɨ̞͡β̞ ɪ̈͡β̞ ʈ͡ɽ̝̊
FreeSans: c͡ʎ̥
FreeSans Bold: c͡ʎ̥ ʈ͡ɽ̝̊
FreeSans Bold Oblique: c͡ʎ̥ ɪ̈͡β̞ ʈ͡ɽ̝̊ ʔ͡h ʕ͡ʡ ʡ͡ʜ ʡ͡ʢ
FreeSans Oblique: c͡ʎ̥ e̞͡β̞ m͡b q͡ǂ ɘ͡β̞ ɛ̝͡β̞ ɡ͡ǂ ɢ͡ǂ ɴ͡ǂ
FreeSerif: ʗ̃͡ʔ
FreeSerif Bold Italic: m͡b n͡d p̪͡f p͡f p͡ɸ q͡ǂ s͡ɸ v͡f ŋ͡ǂ ȹ͡f ɖ͡ɽ̝ ɖ͡ʐ ɘ͡β̞ ɛ̝͡β̞ ɟ͡ʝ ɡ͡ǂ ɢ͡ǂ ɨ̞͡β̞ ɬ͡s ɴ͡ǂ ʃ͡ɬ ʡ͡ʜ ʡ͡ʢ
FreeSerif Italic: m͡b p̪͡f p͡f p͡ɸ s͡ɸ v͡f ȹ͡f ɖ͡ɽ̝ ɖ͡ʐ ɛ̝͡β̞ ɢ͡ǂ ɬ͡s ɴ͡ǂ ʃ͡x ʃ͡ɬ ʈ͡ɽ̝̊

Some of these overlaps are more significant than others.

David Corbett <dscorbett>
Sun 22 Feb 2015 09:26:28 PM UTC, comment #9:

Hi Hsing-yen He,

Let me repeat: my difficulty in fixing this is, I have no information about which characters are combinded with this tie.
Until I know that, I cannot do very much with this.


Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Sun 22 Feb 2015 04:40:40 PM UTC, comment #8:

I have not receive your e-mail from Gmail but found this release at launchpad.net, I think maybe your e-mail was broken by GFW, because CPC authority had broken Gmail ports last year.

Hsing-yen He <hammerandsickle>
Mon 16 Feb 2015 03:55:03 PM UTC, comment #7:

I switch to FreeSans, and I found this font still have problem for these combinations.

Hsing-yen He <hammerandsickle>
Mon 16 Feb 2015 03:49:03 PM UTC, comment #6:

Oh~sorry for my fault, I want to say "I am using 8 Feb. 2015 release".

Hsing-yen He <hammerandsickle>
Mon 16 Feb 2015 03:44:20 PM UTC, comment #5:

Hi Steve,

I copied some texts from here to Unicode Text Styler (http://babelstone.co.uk/Unicode/text.html) for test, they looks very well for me. I am using 8 Feb. 2014 release.

Hsing-yen He <hammerandsickle>
Sun 15 Feb 2015 01:15:52 PM UTC, comment #4:


I had one other thought: maybe you haven't been getting my e-mails at all. You should have gotten (I think) two e-mails, not from the Savannah site but from my private e-mail account.

I also sent an e-mail with a link to the the Google Drive directory.

All these mails to the address listed for your Savannah account. Did you get them?

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Sat 14 Feb 2015 11:43:56 AM UTC, comment #3:

Hi Hsing-yen,

As I said, I can see the problem.

I just have no way of knowing the extent of the use of this combining letter. Until I know that, I'm hesitant to start trying to "fix" it.

To exactly which combinations of letters is this tie applied?

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Fri 13 Feb 2015 05:03:47 PM UTC, comment #2:

Hi Steve,

I have copied some IPA transcriptions from Wikipedia articles (starting from “International Phonetic Alphabet”) to test before I submit this item. I also found these articles referenced some professional phonetic documents such as the Handbook of the International Phonetic Association to explain.

Hsing-yen He <hammerandsickle>
Thu 12 Feb 2015 09:13:55 PM UTC, comment #1:

Hi Hsing-yen.

Well, I see what you mean of course.
Part of the problem here is that we have little in the way of examples.
If you could provide an image from (whatever kind of) a book which shows this combining character being used, that would be very helpful.

But this looks rather messy. A solution might take some time.

Another problem is... with which characters exactly does the tie interact?

Steve White <Stevan_White>
Project AdministratorIn charge of this item.
Thu 12 Feb 2015 06:29:36 PM UTC, original submission:

When I use FreeSerif to display these combinations, The ligature tie (U+0361) will block some part of letter, or positioned aslantly:

p̪͡f, b̪͡v, t͡s, t͡θ, t͡ʃ, ʈ͡ʂ, ɖ͡ʐ, ɡ͡b, t͡ɬ, c͡ç, ɟ͡ʝ, c͡ʎ̝̥
All combinations with ǃ, ǀ, ǁ, ǂ, ʘ (such as ǃ͡q, ǀ͡ɢ, ǁ͡qʰ, k͡ǂ, ɡ͡ǂ, ǂ͡k, ʘ͡q)

Hsing-yen He <hammerandsickle>


(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach Files:

Attached Files


Depends on the following items: None found

Items that depend on this one: None found


Carbon-Copy List
  • -email is unavailable- added by Stevan_White (Posted a comment)
  • -email is unavailable- added by hammerandsickle (Submitted the item)

    Do you think this task is very important?
    If so, you can add your encouragement to it.
    This task has 0 encouragements so far.

    Only logged-in users can vote.




    Follow 7 latest changes.

    Date Changed by Updated Field Previous Value => Replaced by
    2017-04-12 Stevan_White Attached File- => Added FS-ties-issues.html, #40383
    2017-04-12 Stevan_White StatusConfirmed => Proceeding
    2015-02-14 hammerandsickle Attached File- => Added A example of this bug.png, #33072
    2015-02-12 Stevan_White Categoryoverall font problem => individual character(s)
        Item Groupglyph(s) incorrect => letter positioning poor
        StatusNone => Confirmed
        Assigned toNone => Stevan_White

    Back to the top

    Powered by Savane 3.4