[csswg-drafts] [css-fonts-4] The 'features' value of 'font-technology' needs a parameter to identify the specific feature/shaping technology (#6372)

jfkthame has just created a new issue for https://github.com/w3c/csswg-drafts:

== [css-fonts-4] The 'features' value of 'font-technology' needs a parameter to identify the specific feature/shaping technology ==
In the [`font-technology`](https://drafts.csswg.org/css-fonts-4/#font-technology-values) options for the `supports` clause of the `src` descriptor, the `color(...)` value takes an argument that identifies which specific color technology is used.

However, `features` does not currently have a similar argument; I think it should. There are at least three distinct font-feature technologies in current use that each may (or may not) be individually supported by a given user agent: OpenType layout (GSUB/GPOS tables), AAT (morx/kerx tables), and Graphite (Silf and related tables). Given that not all browsers support all of these, the bare keyword `features` is insufficient to determine whether a given resource should be used.

Therefore, I propose that `features`, like `color()`, should take a keyword argument specifying which font feature technology is present; possible values would be `ot` (or `opentype`?), `aat`, and `graphite`. This allows browsers to load only font resources they can properly use, and enables authors to provide alternative fonts if needed.

Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/6372 using your GitHub account


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Received on Wednesday, 9 June 2021 16:08:51 UTC