Turn on harfbuzz shaper by default for Hebrew on all platforms

RESOLVED FIXED in mozilla13

Status

()

Core
Layout: Text
RESOLVED FIXED
6 years ago
5 years ago

People

(Reporter: smontagu, Assigned: jfkthame)

Tracking

(Depends on: 2 bugs)

unspecified
mozilla13
Points:
---
Dependency tree / graph

Firefox Tracking Flags

(Not tracked)

Details

Attachments

(3 attachments)

(Reporter)

Description

6 years ago
Currently harfbuzz is turned on by default for Hebrew on OSX and Android, and for Arabic on all platforms. We need to determine whether there are any issues preventing turning it on for Hebrew on all platforms.
(Reporter)

Updated

6 years ago
Blocks: 721821

Comment 1

6 years ago
Created attachment 592487 [details]
An HTML file with combinations of Hebrew characters and diacritics. Each pair is supposed to look the same.

I am attaching a file with pairs of letters with diacritics. In each pair the characters are the same, but ordered differently. Chromium displays each pair identically. Firefox on Linux with harfbuzz enabled displays the pairs differently.

Comment 2

6 years ago
Created attachment 592488 [details]
A TTF font file with a font that is good for testing Hebrew rendering.

Comment 3

6 years ago
On Linux:
* if the value of gfx.font_rendering.harfbuzz.scripts is 4, then all the pairs in the file hebrew-html-harfbuzz-test-aharoni.html appear different.
* if the value of gfx.font_rendering.harfbuzz.scripts is 3, then the first three pairs appear the same and correct and the last two pairs appear different.
Attachment #592487 - Attachment mime type: text/plain → text/html
(Reporter)

Updated

6 years ago
Blocks: 662055
(Assignee)

Comment 4

6 years ago
Currently, switching to harfbuzz for Hebrew would regress the rendering of older fonts such as those on Windows XP, which rely on using the Unicode presentation form codepoints for letters with dagesh (and a few other combinations).

Filed bug 728866 to address this. Once that is resolved, I think we could seriously consider switching on harfbuzz by default for all platforms.
(Assignee)

Updated

6 years ago
Depends on: 728866
(Assignee)

Comment 5

6 years ago
Created attachment 599072 [details] [diff] [review]
patch, turn on harfbuzz for hebrew on all platforms

I _think_ we're at the point where it makes sense to do this; Simon?
Attachment #599072 - Flags: review?(smontagu)
(Reporter)

Updated

6 years ago
Attachment #599072 - Flags: review?(smontagu) → review+
(Assignee)

Comment 6

6 years ago
Pushed to inbound:
https://hg.mozilla.org/integration/mozilla-inbound/rev/063e67b9f910

This should give us more uniform behavior for Hebrew, where previously the results varied significantly between platforms, especially with regard to diacritic handling.

(The one exceptional case will be AAT fonts on OS X, which still go through the Core Text path.)
Assignee: nobody → jfkthame
Status: NEW → ASSIGNED
Target Milestone: --- → mozilla13

Comment 7

6 years ago
https://hg.mozilla.org/mozilla-central/rev/063e67b9f910
Status: ASSIGNED → RESOLVED
Last Resolved: 6 years ago
Resolution: --- → FIXED

Updated

5 years ago
Depends on: 727560

Updated

5 years ago
Depends on: 762028

Updated

5 years ago
Depends on: 763300

Updated

5 years ago
Depends on: 778565
You need to log in before you can comment on or make changes to this bug.