445489 - [10.4] Persian (Arabic) joining is broken with some fonts

Status: RESOLVED WONTFIX

(Core :: Graphics, defect)

Description

[gesus]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; de; rv:1.9) Gecko/2008061015 Firefox/3.0
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; de; rv:1.9) Gecko/2008061015 Firefox/3.0

On Mac OS X (Tiger) there seems to be a problem with some persian letters. They are not connected correctly. Others are connected correctly. This problem seems to occur on Mac OS (Tiger) only. On Leopard Linux and windows there's  no problem.

See the screenshots (especially the highlighted areas) for more information.

Reproducible: Always

Steps to Reproduce:
1. Go to the page http://khanoomche.wordpress.org (or http://khanoomche.wordpress.com/2008/07/14/%D8%B5%D8%AF%D8%A7%DB%8C-%D8%A2%D9%85%D8%B1%DB%8C%DA%A9%D8%A7/)
2. Look at the topic صدای آمریکا
3. 
Actual Results:  
Letters "صدای آمریکا" are not connected correctly as as you can see in the screenshot firefox3.png

Expected Results:  
Letters should be connected like in the screenshot firefox2.png

On the same system there is no problem with safari or firefox2.

Comment 1

[gesus]

Attachment: correct display (using Firefox2)

Comment 2

[gesus]

Attachment: incorrect display (using Firefox3)

Comment 3

[Steven Michaud [:smichaud] (Retired)]

I'm not competent to address this problem (I don't know Farsi, or
anything about Arabic-related scripts).

But I wonder if it's a problem with a particular font (in other words,
I wonder if FF3 on your Tiger installation is using a different font
than the other configurations are using).

Comment 4

[Simon Montagu :smontagu]

This does looks like a font issue. I can reproduce with the default font settings, but not if I change the preference for Arabic serif font from Al Bayan to Geeza Pro. It looks as if the version of Al Bayan on Tiger doesn't have good shaping tables for some characters used in Persian but not in Arabic.

Comment 5

[(no longer active)]

I don't have a Mac, so I can't tell for sure, but from the screenshots it seems evident that the fonts used in Firefox 2 and 3 pages are different.

gesus: can you try to set the preferences for Firefox 2 to use the same font as Firefox 3 by default on your system?  Also, can you check which default fonts Safari is using?

Simon: Is there any way to test these fonts on other platforms?

Comment 6

[Behnam Esfahbod [:zwnj]]

The fonts gesus is using are Terafik, Nesf and another one which is the broken one.  You can see that the same characters that are broken in the sidebar (CHEH and KEHEH) and in the title (FARSI YEH and KEHEH) are displayed correctly in the main content.  IMO it's INVALID.

Comment 7

[gesus]

@ehsan: I'm sorry, but the Mac I was using is not mine. I will be able to test this on that computer next weekend. Sorry for that delay.

Comment 8

[Simon Montagu :smontagu]

(In reply to comment #5)
> Simon: Is there any way to test these fonts on other platforms?

No, they are AAT (Apple Advanced Typography) fonts, which don't work on other platforms because they use different tables for glyph substitution and positioning.

Comment 9

[gesus]

Safari is using Times 16 (default font) and Courier 13 (non proportional font).

Firefox 2 is using the following default fonts for arabic:
Sans Serif (proportional)
Lucida Grande (Serif)
Lucida Grande (Sans-Serif)
Monaco (fixed width)

Firefox 3 is using this default fonts:
Sans Serif (proportional)
Al Bayan (Serif)
Geeza Pro (Sans-serif)
Geeza Pro (fixed-width)

I tried to set the default fontset in Firefox 3 as in version 2 but the page has the same errors with that. 

To set the other way round (set the default fontset in Firefox 2 as in version 3) was not completely possible, because the font Firefox 3 is using for Serif fonts (named Al Bayan") was not in the list. (Maybe I do something wrong; I'm not really familar with Macs). Firefox 2 displayed the page in a correct way. 

The fonts Behnam mentioned (Terafik, Nesf) don't seem to be installed on this system.

Comment 10

[(no longer active)]

So, can you check to see if the same problem happens in a reduced test case with Al Bayan and Geeza Pro fonts?

Comment 11

[gesus]

The page is correctly displayed with Firefox 2 when I select only Geeza Pro. I still wasn't able to find a way to find or select Al Bayan in Firefox 2 :-/

Comment 12

[Smokey Ardisson (offline for a while; not following bugs - do not email)]

Firefox 2 only supported Geeza Pro, and only then via a massive hacky work-around (the old Gfx:Mac font code dated from the 1990s and was horribly, horribly broken).

Neither Firefox 2 nor Safari are actually using the fonts listed in comment 9; they're both falling back to a real Arabic script font; Safari only lets you set one font for all langGroups, and Firefox 2 uses Lucida Grande and Monaco to force fallback to work-around the broken font code.

I hate to switch everyone back to the bland old Geeza Pro for serifs because Al-Bayan is broken for Persian on 10.4, but I think that's the best course of action here, unless John or Simon have some brilliant idea I've missed.

Comment 13

[Simon Montagu :smontagu]

(In reply to comment #12)

> I hate to switch everyone back to the bland old Geeza Pro for serifs because
> Al-Bayan is broken for Persian on 10.4, but I think that's the best course of
> action here, unless John or Simon have some brilliant idea I've missed.

How about a release note advising Persian users on 10.4 to switch to Geeza Pro?

Comment 14

[(no longer active)]

(In reply to comment #13)
> How about a release note advising Persian users on 10.4 to switch to Geeza Pro?

Seems better than nothing.  Is it possible to push it into release notes for 3.0?

Comment 15

[Samuel Sidler (old account; do not CC)]

(In reply to comment #14)
> Seems better than nothing.  Is it possible to push it into release notes for
> 3.0?

Yes, we definitely can. Can either one (or both) of you please email me offline ([e-mail]) with some starter text for this so I can make sure I get it right?

Comment 16

[Morteza Milani]

Hi, I have this problem in Firefox 6.

Everything was ok when I worked with Firefox 5 or below but when I upgraded to Firefox 6, Persian Fonts included in pages with @font-face are now broken. For example you can see: http://weapi.org

I'm sure it is not a problem with font itself because it was working fine in FF 5 or below. Also this problem only happens in linux not any other OS I think but I'm not sure.

Comment 17

[Jonathan Kew [:jfkthame]]

(In reply to Morteza Milani from comment #16)
> Hi, I have this problem in Firefox 6.
> 
> Everything was ok when I worked with Firefox 5 or below but when I upgraded
> to Firefox 6, Persian Fonts included in pages with @font-face are now
> broken. For example you can see: http://weapi.org
> 
> I'm sure it is not a problem with font itself because it was working fine in
> FF 5 or below. Also this problem only happens in linux not any other OS I
> think but I'm not sure.

This bug report was specifically related to OS X 10.4.

The issue you're seeing on the http://weapi.org page is that the downloadable font used (BYekan.ttf) is faulty, and newer versions of Firefox reject the bad OpenType tables. See bug 674335 for discussion of the same problem (on a different site).

Comment 18

[Jeff Muizelaar [:jrmuizel]]

10.4 is no longer supported, sorry.