1370927 - Two-part vowels are misrendered with default Oriya font

Status: RESOLVED FIXED

(Core :: Layout: Text and Fonts, defect, P3)

Description

[corbett.dav]

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.11; rv:54.0) Gecko/20100101 Firefox/54.0
Build ID: 20170601133324

Steps to reproduce:

I rendered the following in macOS 10.11.5. ⟨ଖୋ⟩ is an Oriya consonant with a two-part vowel. Oriya MN is the default Oriya serif font in Firefox on macOS.

data:text/html;charset=utf-8,<div style="font: 100px Oriya MN">%E0%AC%96%E0%AD%8B


Actual results:

The text was rendered: consonant, left vowel part, dotted circle, right vowel part, right vowel part.


Expected results:

The text should have been rendered: left vowel part, consonant, right vowel part.

This bug also happens with Oriya Sangam MN, another default Mac font. It also happens with other Oriya consonants and two-part vowels. It does not happen with other Indic scripts in other AAT fonts in Firefox; e.g. ⟨ഖോ⟩ looks correct with Malayalam MN. It does not happen with default macOS programs like TextEdit. It does not happen with hb-shape 1.4.6:

$ echo ଖୋ | hb-shape '/Library/Fonts/Oriya MN.ttc'
[ori_e_matra=0+886|ori_kha=0+1240|ori_aa_matra=0+296]

Comment 1

[Jonathan Kew [:jfkthame]]

Attachment: For Oriya AAT fonts (as for Bengali and Kannada) enable the Line Initial Smart Swashes feature, which is (incorrectly) required for split-vowel matras to render properly

Sigh... buggy Apple fonts strike again. We've fixed (or rather, hacked around) this issue for a couple of scripts previously, but it seems Oriya needs the same treatment.

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/d6c441551c09
For Oriya AAT fonts (as for Bengali and Kannada) enable the Line Initial Smart Swashes feature, which is (incorrectly) required for split-vowel matras to render properly. r=jrmuizel

Comment 3

[Sebastian Hengst [:aryx] (needinfo me if it's about an intermittent or backout)]

https://hg.mozilla.org/mozilla-central/rev/d6c441551c09