Bug 255972 - [Harfbuzz] Some Arabic fonts are not being shaped correctly
Summary: [Harfbuzz] Some Arabic fonts are not being shaped correctly
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: WebKitGTK (show other bugs)
Version: Other
Hardware: PC Linux
: P2 Normal
Assignee: Nobody
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2023-04-25 22:58 PDT by Saadat Mateen
Modified: 2024-06-30 10:31 PDT (History)
4 users (show)

See Also:

Attachments
Incorrect rendering of Noto Nastaliq Urdu in Epiphany 44.1 (314.03 KB, image/png)
2023-04-25 22:59 PDT, Saadat Mateen 		no flags Details
Correct rendering of Noto Nastaliq Urdu in Firefox 112.0.1 (336.55 KB, image/png)
2023-04-25 23:00 PDT, Saadat Mateen 		no flags Details
Incorrect rendering of Mada in Epiphany 44.1 (164.19 KB, image/png)
2023-04-25 23:01 PDT, Saadat Mateen 		no flags Details
Correct rendering of Mada in Firefox 112.0.1 (226.71 KB, image/png)
2023-04-25 23:01 PDT, Saadat Mateen 		no flags Details
Incorrect rendering of Noto Sans Arabic in Epiphany 44.1 (288.06 KB, image/png)
2023-04-25 23:02 PDT, Saadat Mateen 		no flags Details
Correct rendering of Noto Sans Arabic in Firefox 112.0.1 (310.02 KB, image/png)
2023-04-25 23:02 PDT, Saadat Mateen 		no flags Details
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Description Saadat Mateen 2023-04-25 22:58:03 PDT 
# Platform details

Epiphany version: 44.1
WebKitGTK: 2.40.1
GStreamer: 1.22.2
Distributor: Fedora Linux 38 (Workstation Edition)

# Issue

Text set in some Arabic fonts is not being shaped correctly. Depending on the font, following issues are occurring:

1. Vertical positioning of glyphs is incorrect.
   URL: https://fonts.google.com/noto/specimen/Noto+Nastaliq+Urdu

2. All marks (dots/diacritics) are in wrong positions, and separate lines of a paragraph are jumbled.
   URL: https://fonts.google.com/specimen/Mada

3. Some diacritics are incorrectly positioned.
   URL: https://fonts.google.com/noto/specimen/Noto+Sans+Arabic

Examples of various other Arabic fonts with incorrect shaping may also be seen at https://fonts.google.com/?subset=arabic&noto.script=Arab
Comment 1 Saadat Mateen 2023-04-25 22:59:14 PDT 
Created attachment 466085 [details]
Incorrect rendering of Noto Nastaliq Urdu in Epiphany 44.1
Comment 2 Saadat Mateen 2023-04-25 23:00:11 PDT 
Created attachment 466086 [details]
Correct rendering of Noto Nastaliq Urdu in Firefox 112.0.1
Comment 3 Saadat Mateen 2023-04-25 23:01:09 PDT 
Created attachment 466087 [details]
Incorrect rendering of Mada in Epiphany 44.1
Comment 4 Saadat Mateen 2023-04-25 23:01:29 PDT 
Created attachment 466088 [details]
Correct rendering of Mada in Firefox 112.0.1
Comment 5 Saadat Mateen 2023-04-25 23:02:10 PDT 
Created attachment 466089 [details]
Incorrect rendering of Noto Sans Arabic in Epiphany 44.1

Some incorrect positioning instances marked with a red circle.
Comment 6 Saadat Mateen 2023-04-25 23:02:36 PDT 
Created attachment 466090 [details]
Correct rendering of Noto Sans Arabic in Firefox 112.0.1