[css-fonts-4] [varfont] Italic & Oblique benefit from not including a <number>

[litherum]

Migrated on behalf of @nattokirai:

For variable fonts in OpenType, two axes have been defined, the 'ital' axis and the 'slnt' axis (for slant). The value of 'italic' should map to the value defined in the 'STAT' table. The value of 'oblique' should map to the value defined in the 'STAT' table. If the value is 'italic' and the 'ital' axis does not exist, look for the value of 'oblique' and use the 'slnt' axis instead. Similarly for when 'oblique' is specified but no 'slnt' axis exists. If neither axis exists, use synthetic oblique. Other combinations of values along either the italic or slant axes can be expressed using the font-variation-settings property.

[Crissov]

JFTR, that would mean, font-style: normal | italic | oblique would remain unchanged.

I‘ve seen backwards italic, semi-slant italic and upright italic fonts before, so I don’t get why these should be excluded. (I would use <percentage> and <angle> instead of <number>, but that’s a different issue.)

[litherum]

I know of a case where reverse-obliqued text is typographically valuable in some situations, but regularly-obliqued text is typographically valuable in other situations, where both situations use the same font. This would be a reason to allow the number.

I'd be interested to hear what other browsers have to say. (Does Jonathan Kew have a GitHub account?) cc @SergeyMalkin @PeterCon

[litherum]

Is there any other support for this proposal? I'm thinking about closing it.

[davelab6]

Is there any other support for this proposal? I'm thinking about closing it.

I like this proposal! :)

I‘ve seen backwards italic, semi-slant italic and upright italic fonts before, so I don’t get why these should be excluded

Those are much more rare cases, though; normal | italic | oblique is a short hand, which this proposal makes work in a simple way for VF. Simplicity is important and valuable.

Indeed, oblique is already a rare option, a subtlety of typography :) The rarer cases can be handled by (more complex) vf css settings.

Does Jonathan Kew have a GitHub account?

Yes, @jfkthame

[litherum]

Are we still interested in pursuing this? The last comment was over a year ago.

[css-meeting-bot]

The Working Group just discussed Italic & Oblique benefit from not including a <number>, and agreed to the following:

• RESOLVED: Close the issue no-change, fantasai to write a comment for opentype spec authors

The full IRC log of that discussion

<fantasai> Topic: Italic & Oblique benefit from not including a <number>
<fantasai> github: https://github.com//issues/519
<frremy> chris_: I read the entire issue, and didn't understand what the issue was about
<frremy> myles: I think the proposal is relative to variable fonts
<frremy> myles: You started being able to say "oblique 30deg"
<frremy> myles: Would prefer this not to be allowed
<frremy> chris_: why? you can still not define it if you dont want
<frremy> fantasai: otherwise you get the value defined in the spec
<fantasai> fantasai: not a value taken from the font
<frremy> myles: if you specify "oblique 0" you get roman
<frremy> myles: but with variable fonts, but you could make a 0deg oblique
<frremy> fantasai: is there a field that says what the preferred oblique angle is?
<frremy> myles: there is the concept of named instances
<frremy> myles: you can say then "oblique" is this set of values
<frremy> chris_: but the names are not standardized
<frremy> myles: right, this isn't formal enough for us to rely on
<frremy> myles: there might be one in there with italic, but there might be many
<frremy> chris_: and it could be localized
<frremy> chris_: so let's not do this
<frremy> chris_: proposal is to close no action
<frremy> myles: I agree
<frremy> fantasai: and add a comment that if the font authors add some field for a value
<frremy> fantasai: otherwise we will not do anything
<fantasai> s/font authors/Opentype spec/
<fantasai> s/value/value then we can consider using that instead of 14/
<frremy> RESOLVED: Close the issue no-change, fantasai to write a comment for opentype spec authors

[fantasai]

To clarify the above resolution, as far as we can tell, there's no field in OpenType that would let us know what the font designer's preferred oblique angle would be. We're therefore using 14 as the default slant. If OpenType later adds a field for "default angle for obliques", then we can consider using that instead of 14.

[PeterCon]

It's not clear what the issue is. Is it specifically related to variable fonts, or just any font? And is it about what the UA should do with "font-style:oblique", with no number specified?

[fantasai]

@PeterCon We are actually quite confused as to what the issue actually is about, the conversation above is our best attempt to address it. :)

[fantasai]

If there's something we've missed, please let us know!