361778 - Firefox not rendering Malayalam characters properly.

Status: RESOLVED FIXED

(Core :: Graphics, defect)

Description

[Biju]

Firefox not rendering Malayalam characters properly.
see attachment FF_IE_malayalam.png
under "America" is "New Jersey" is not displayed


Steps:-
1. Run Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9a1) Gecko/20061124 Minefield/3.0a1
2. goto http://snipurl.com/1370t#.E0.B4.85.E0.B4.AE.E0.B5.87.E0.B4.B0.E0.B4.BF.E0.B4.95.E0.B5.8D.E0.B4.95
(ie http://varamozhi.wikia.com/wiki/Geographical_Locations_of_Malayalam_Bloggers#.E0.B4.85.E0.B4.AE.E0.B5.87.E0.B4.B0.E0.B4.BF.E0.B4.95.E0.B5.8D.E0.B4.95 )

3. You should see "America" in Malayalam
4. under America is "New Jersey", but Firefox render it as boxes.


PS:
tested in WinXP default Kartika font, 
and AnjaliOldLipi font download from
http://prdownloads.sourceforge.net/varamozhi/AnjaliOldLipi-0.730.ttf?use_mirror=kent

Comment 1

[Biju]

Attachment: FF_IE_malayalam.png

Comment 2

[Biju]

Attachment: FF_2_malayalam.png

as displayed in
Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1pre) Gecko/20061124 BonEcho/2.0.0.1pre

Comment 3

[Simon Montagu :smontagu]

The problem seems to occur chiefly in lines containing a zero-width non-joiner character (U+200C), but sometimes also with a zero-width joiner (U+200D).

Comment 4

[Simon Montagu :smontagu]

Attachment: minimized testcase

Comment 5

[Simon Montagu :smontagu]

This is a regression from bug 355917.

Comment 6

[Simon Montagu :smontagu]

This totally broke rendering of scripts using zero-width joiners and non-joiners. I'm not sure why there are still zero-width glyphs after calling Shape(), but apparently there are.

Comment 7

[Simon Montagu :smontagu]

Sorry, previous comment was in the wrong bug

Comment 8

[Stuart Parmenter]

ah -- i was afraid that patch would break some stuff, but couldn't find any examples.

Comment 9

[Simon Montagu :smontagu]

Attachment: Harder minimized testcase

I had an idea to fix this, and it fixes a lot of cases but not all. Expanding the minimized testcase to include a case that it didn't fix.

Comment 10

[Simon Montagu :smontagu]

Attachment: Don't reject zero-width gyphs in non-complex scripts

This is kind of hacky, but it fixes the Malayalam regressions without regressing bug 355917.

Comment 11

[Stuart Parmenter]

Comment on attachment 247092 [details] [diff] [review]
Don't reject zero-width gyphs in non-complex scripts

sounds good to me for now

Comment 12

[Simon Montagu :smontagu]

Checked in.

Comment 13

[Simon Montagu :smontagu]

*** Bug 362271 has been marked as a duplicate of this bug. ***

Comment 14

[Simon Montagu :smontagu]

*** Bug 361786 has been marked as a duplicate of this bug. ***