- From: Dominik Röttsches via GitHub <sysbot+gh@w3.org>
- Date: Tue, 07 Nov 2023 09:58:05 +0000
- To: public-css-archive@w3.org
> And how do the extents in the 'head' table work in the case of variable fonts? Do they indicate the maximum bounding box under any combination of variation settings, or the bounding box of the default instance? The spec does not appear to provide for applying deltas to these fields, AFAICS. Good point, the spec says [further below](https://learn.microsoft.com/en-us/typography/opentype/spec/head#:~:text=Also%2C%20in%20a%20variable%20font): > "Also, in a variable font, [...] the xMin, yMin, xMax and yMax values in this table might or might not encompass the derived glyph outlines for an instance. Also, variation deltas are not provided for these values. If an application requires a bounding rectangle that encompasses the glyphs for a non-default instance of the font, the derived glyph outlines for the instance should be processed to determine a bounding rectangle." So these HEAD table font-level metrics are not particularly reliable and even unusable for variable fonts. Glyph-level determination of bounding boxes is more accurate, and can take variations into account, but is relatively expensive to compute. -- GitHub Notification of comment by drott Please view or discuss this issue at https://github.com/w3c/csswg-drafts/issues/8649#issuecomment-1798177345 using your GitHub account -- Sent via github-notify-ml as configured in https://github.com/w3c/github-notify-ml-config
Received on Tuesday, 7 November 2023 09:58:07 UTC