Anchor attachment

Hello. What kind of errors can I encounter if I add anchors to caron or other diacritics? I should also say that there are caroncomb and other combinations.
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  • John Hudson
    John Hudson Posts: 3,204
    Do you mean anchors to attach combining marks to other glyphs, or to attach combining marks to combining marks, or ?
  • The glyph called "caron" in the Adobe Glyph List For New Fonts is mapped to U+02C7 CARON. Since you mention there is caroncomb, which should map to U+030C, I’ll assume you mean caron as U+02C7.

    U+02C7 is a spacing character and can be used in some phonetic notations as a caron next to the letter it modifies. U+030C is a non spacing combining character and is the one uses in general when Central European characters č ď ľ ť ž are decomposed at the character level (at the glyph level ď ľ ť typically have a variant form of the caron, exceptionally like in some phonetic transcription or other orthographies they may not).
    Both are diacritics, depending on the definition.

    The only anchors U+02C7 should have are anchors to attach combining marks to it.
    U+030C is the one that should have anchors to attach it to base letters or to other combining marks.
    For example ˇ̌ is U+02C7 U+030C and a Unicode font with proper support should place the non-spacing combining caron on top of the spacing modifier letter caron.

    In font editors, this should be a "top" anchor in caron and a "_top" anchor in caroncomb.
    For other top marks to stack with caroncomb, it should have a "top" anchor as well.

    If you add a "_top" anchor to caron, as if it were a non-spacing combining mark, it will misbehave and will not be positioned appropriately.



  • Or do you mean what if you add an anchor to the spacing caron at U+02C7 instead of, or in addition to, the combining caron at U+030C?

    The combining caron (U+030C) benefits from having an anchor. The spacing one (U+02C7) does not.

    I am not sure that there is any inherent problem from having an anchor on both, but I would suggest avoiding it as a matter of principle. U+02C7 is not a combining mark, and making its glyph seem like a combining mark might confuse someone, with no benefit I can think of.
  • The only anchors U+02C7 should have are anchors to attach combining marks to it.
    U+030C is the one that should have anchors to attach it to base letters or to other combining marks.
    For example ˇ̌ is U+02C7 U+030C and a Unicode font with proper support should place the non-spacing combining caron on top of the spacing modifier letter caron.
    Of all the fonts included with Windows, only Segoe UI Variable seems to meet this criterion.



    The preview text is:
    /a /a/brevecomb /a/brevecomb/caronmod /a/caronmod/brevecomb /a/caroncomb/caronmod /a/caronmod/caroncomb /newline /c /c/brevecomb /c/brevecomb/caronmod /c/caronmod/brevecomb /c/caroncomb/caronmod /c/caronmod/caroncomb


  • Maybe I didn't explain correctly. For example, when creating a dieresis with 'a' or an acute with 'a' in Fontlab, it automatically matches the dieresis or acute glyph to produce á or ä. So It doesn't look right because these diacritics don't have anchors. Therefore, I created combinations anchored by these diacritics. The thing is, these creations of mine are not automatically compatible with each other, and I manually fix them. So I'm asking, if I add an anchor to the default diacritics, won't the result fail?

    Finally I made both glyphs as you can see in the screenshot. Let it automatically match whichever one it prefer. I'm just worried, I don't know what kind of problem this could be later.


  • John Hudson
    John Hudson Posts: 3,204
    Don’t make composite diacritics using the spacing accent (modifier) character glyphs. Always use the combining mark character glyphs. So, for example, the /aacute/ glyph should be a composite of /a/ and /acutecomb/ (U+0301).