Bug 257200
| Summary: | Ignore bidi control characters while collecting fallback fonts | ||
|---|---|---|---|
| Product: | WebKit | Reporter: | Amanda Falke <abstractmachines> |
| Component: | Text | Assignee: | Nobody <webkit-unassigned> |
| Status: | RESOLVED FIXED | ||
| Severity: | Normal | CC: | mmaxfield, webkit-bug-importer |
| Priority: | P2 | Keywords: | InRadar |
| Version: | WebKit Nightly Build | ||
| Hardware: | Unspecified | ||
| OS: | Unspecified | ||
Amanda Falke
https://drafts.csswg.org/css-text-3/#white-space-processing
"Unsupported Default_ignorable characters must be ignored for text rendering."
As mentioned in 245154@main, taking zero width glyphs (e.g. control characters) into consideration while collecting fallback font information
may result in incorrect line height and baseline positioning; an alternative mentioned in 245154@main was to check against unicode ranges to omit
certain glyphs.
246121@main fixed a regression in which bidi control chars rendered, and replaced our previous hardcoded list of Default_ignorable characters with the helper
function,FontCascade::isCharacterWhoseGlyphsShouldBeDeletedForTextRendering (also refactored in 260081@main). That helper function covers the use case 'rightToLeftOverride' which the test `LayoutTests/fast/text/fallback-font-and-zero-width-glyph.html`, currently marked as failing in glib, relies on.
| Attachments | ||
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| Add attachment proposed patch, testcase, etc. |
Amanda Falke
PR, WIP. https://github.com/WebKit/WebKit/pull/14240
EWS
Committed 264509@main (07b1f5f81cef): <https://commits.webkit.org/264509@main>
Reviewed commits have been landed. Closing PR #14240 and removing active labels.
Radar WebKit Bug Importer
<rdar://problem/109820978>