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<div class="moz-cite-prefix">On 2024-02-22 6:59 am, Simon Cozens via
mpeg-otspec wrote:<br>
</div>
<blockquote type="cite"
cite="mid:87f9b17d-447c-4b51-baae-86ba3fa654e1@simon-cozens.org">When
Behdad, I and others did some thinking about the JSTF table last
year (with a view to potentially making a 2.0 version which
interacted better with variable fonts), we came to the realisation
that everything you can do with the JSTF table, you can actually
now do with a "JSTF" axis. So at this point it's entirely
redundant.
<br>
<br>
In fact, I think Behdad implemented JSTF-axis-based justification
in harfbuzz. (hb_shape_justify)
</blockquote>
<p>How does the axis handle prioritisation of justification
techniques?</p>
<p><br>
</p>
<p>In answer to Nate’s query about how the JSTF table made it into
the spec, I discussed this, quite a few years ago, with Eliyezer
Kohen. The table had been spec’d to provide mechanisms to address
Arabic justification as the problem space had been described to
Eliyezer by Tom Milo. This involved being able to define multiple
mechanisms to affect justification—alternate forms, elongation,
spacing adjustments—and then <i>prioritise</i> these mechanisms.
I think Nate is quite right that the table is not useful or really
understandable without a corresponding justification engine
specification, and my impression has long been that the JSTF table
spec was something that would need to be revised in implementation
(as various other parts of OpenType have been).<br>
</p>
<p>JH<br>
</p>
<p><br>
</p>
<pre class="moz-signature" cols="72">--
John Hudson
Tiro Typeworks Ltd <a class="moz-txt-link-abbreviated" href="http://www.tiro.com">www.tiro.com</a>
Tiro Typeworks is physically located on islands
in the Salish Sea, on the traditional territory
of the Snuneymuxw and Penelakut First Nations.
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