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<div class="moz-cite-prefix">On 4/23/24 11:43, Behdad Esfahbod
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CAF63+7U=_CbStDHZEeVamCuodG7VHH_M-zHpJzP=kxoiA3-e5Q@mail.gmail.com">
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<div dir="ltr">Hi Skef,
<div><br>
</div>
<div>I'm implementing the ConditionValue proposal, and have some
feedback. This is based on the following document:</div>
<div>units<br>
</div>
<div> <a
href="https://github.com/adobe-type-tools/opentype-spec-drafts/blob/main/condvalue_spec.md"
moz-do-not-send="true" class="moz-txt-link-freetext">https://github.com/adobe-type-tools/opentype-spec-drafts/blob/main/condvalue_spec.md</a></div>
<div><span
style="color:rgb(31,35,40);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Noto Sans",Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";font-size:16px"><br>
</span></div>
<div>"""</div>
In "FeatureVariations Table", note that if minorVersion is 0
then only Condition Table version 1 can be used. If minorVersion
is 1 then Condition Table version 2 can also be used.<br>
"""<br>
I highly suggest removing this. The minorVersion is for when new
fields are added to FeatureVariations table itself. It should
not be relied on for anything else.<br>
<br>
</div>
</blockquote>
<p>That can be a solid suggestion for a future change. The proposals
are in now. <br>
</p>
<p>The thought was to try to discourage fonts that would look like
they were<br>
compatible with the previous spec but contained new condition
format types,<br>
but I suppose it doesn't really accomplish that anyway.</p>
<p>Note that the existing (pre-working draft) Open Font Format
specification <br>
screwed up the advice of what to do when a new condition format is
added,<br>
referring to the version of a condition set, which doesn't exist.
Therefore we <br>
don't really know what implementations will do when they encounter
new <br>
condition types. The two obvious choices are "ignore" and "treat
the condition<br>
set containing the condition as not applying, but unfortunately
those are<br>
quite different.</p>
<blockquote type="cite"
cite="mid:CAF63+7U=_CbStDHZEeVamCuodG7VHH_M-zHpJzP=kxoiA3-e5Q@mail.gmail.com">
<div dir="ltr">"""<br>
Add new subpart between "Condition Table Format 1: Font
Variation Axis Range" and "FeatureTableSubstitution Table" with
this content:<br>
"""<br>
Can we name Format1 simply ConditionAxisRange? That would go
better with ConditionValue, ConditionAnd, ConditionOr, and
ConditionNegate.<br>
<br>
</div>
</blockquote>
I recall seeing this in a recent draft of your proposal, so
presumably that<br>
will happen. Seems fine to me.<br>
<blockquote type="cite"
cite="mid:CAF63+7U=_CbStDHZEeVamCuodG7VHH_M-zHpJzP=kxoiA3-e5Q@mail.gmail.com">
<div dir="ltr">"""<br>
On page 166: "Within the GPOS, JSTF, GDEF and BASE tables,
delta-set indices are stored in VariationIndex tables."
<div>"""</div>
<div>I don't understand this. What is a VariationIndex table?</div>
<div><br>
</div>
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</blockquote>
<p>That's, I believe, section 6.2.8 or alternatively
<a class="moz-txt-link-freetext" href="https://learn.microsoft.com/en-us/typography/opentype/spec/chapter2#device-and-variationindex-tables">https://learn.microsoft.com/en-us/typography/opentype/spec/chapter2#device-and-variationindex-tables</a>
(scroll down a bit from this anchor). But I'm not sure how that
would be relevant to what you're currently implementing. <br>
</p>
<p>Skef</p>
<p><br>
</p>
<blockquote type="cite"
cite="mid:CAF63+7U=_CbStDHZEeVamCuodG7VHH_M-zHpJzP=kxoiA3-e5Q@mail.gmail.com">
<div dir="ltr">
<div>Thanks,</div>
<div><br>
</div>
<div>
<div>
<div dir="ltr" class="gmail_signature"
data-smartmail="gmail_signature">behdad<br>
<a href="http://behdad.org/" target="_blank"
moz-do-not-send="true" class="moz-txt-link-freetext">http://behdad.org/</a></div>
</div>
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