[Webkit-unassigned] [Bug 171368] New: GSUB rvrn FeatureVariations not working

bugzilla-daemon at webkit.org bugzilla-daemon at webkit.org
Thu Apr 27 00:42:29 PDT 2017


https://bugs.webkit.org/show_bug.cgi?id=171368

            Bug ID: 171368
           Summary: GSUB rvrn FeatureVariations not working
           Product: WebKit
           Version: WebKit Nightly Build
          Hardware: Unspecified
                OS: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: Text
          Assignee: webkit-unassigned at lists.webkit.org
          Reporter: d-r at roettsches.de
                CC: litherum at gmail.com, mmaxfield at apple.com

Created attachment 308361

  --> https://bugs.webkit.org/attachment.cgi?id=308361&action=review

rvrn FeatureVariations testcase

The rvrn feature [1] and the FeatureVariations part of GSUB describe
single glyph substitutions dependent on variation axis values. 

The variabletest_box.ttf font I am attaching was
extended to have two new glyphs for r and R respectively displaying
"rvrn base" and "rvrn subst" (for "substituted"). When a new axis
'fvtt', ranging from 0 to 10, is set to >= 5, the rvrn_base glyph is
replaced with the rvrn_subst glyph. This enables creating a reftest of
where a lowercase r with font-variation-settings: "fvtt" 10; must match
the uppercase R, which selects the "rvrn_subst" glyph explicitly.

[1] https://www.microsoft.com/typography/OTSpec/features_pt.htm#rvrn

The test case attached fails to work in WebKit nightly r215833.

I am planning on upstreaming the test case WPT css/fonts-4, including the font which has more variation testing features.

-- 
You are receiving this mail because:
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.webkit.org/pipermail/webkit-unassigned/attachments/20170427/90dd16a8/attachment.html>


More information about the webkit-unassigned mailing list