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<p>On 2020-08-17 8:58 a.m., Khaled Hosny via Unicode wrote:
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cite="mid:EF8B7E64-B619-42A9-8811-1FD1DECD46B5@gmail.com">
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<pre class="moz-quote-pre" wrap="">On Aug 17, 2020, at 10:37 AM, Richard Wordingham via Unicode <a class="moz-txt-link-rfc2396E" href="mailto:unicode@unicode.org"><unicode@unicode.org></a> wrote:
Is the
recommendation applicable to Indic scripts, where glyph stream to
character stream conversion may be as complicated as the
reverse direction and there is a natural tendency for distinctions to
be lost. (In Devanagari, the distinction between mandated and
fallback half-forms is one example.)
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Same workflows can’t handle one to many substitution, or reordering, so when I’m doing fonts that need these I usually just give up on the “unique glyph per code point” requirement. I also forget about it when making Arabic fonts, because extracting Arabic text reliably from PDFs generated with such workflows is a lost cause already.</pre>
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<p>A particular workflow might be enhanced to handle, for example,
U+093F DEVANAGARI VOWEL SIGN I where the glyph for this character
is re-ordered compared to the codepoints. I don't see how a
workflow would be able to handle [1] where in Kannada script,
codepoints are re-ordered to handle changing conventions in
encoding. That is, the codepoints are re-ordered before mapping to
glyphs, so two different sequences of codepoints will produce the
same glyph stream, IIUC.<br>
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<p>[1]
<a class="moz-txt-link-freetext" href="https://github.com/harfbuzz/harfbuzz/issues/435#issuecomment-335560167">https://github.com/harfbuzz/harfbuzz/issues/435#issuecomment-335560167</a><br>
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<p>Regards, Bobby</p>
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cite="mid:EF8B7E64-B619-42A9-8811-1FD1DECD46B5@gmail.com">
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<div class="moz-signature">-- <br>
Bobby de Vos<br>
<em><a class="moz-txt-link-abbreviated" href="mailto:bobby_devos@sil.org">bobby_devos@sil.org</a></em><br>
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