Fix Tamil unicode rendering with **opentype** layout tables

RESOLVED INCOMPLETE

Status

()

RESOLVED INCOMPLETE
16 years ago
10 years ago

People

(Reporter: mannan, Assigned: prabhat.hegde)

Tracking

Trunk
x86
Linux
Points:
---

Firefox Tracking Flags

(Not tracked)

Details

(URL)

Attachments

(2 attachments)

(Reporter)

Description

16 years ago
User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3) Gecko/20030312
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3) Gecko/20030312

Like bug 140013 but for Linux. (It seems that bug 140013 is invalid.)


Reproducible: Always

Steps to Reproduce:
1.
2.
3.
(Assignee)

Comment 1

16 years ago
To re-iterate what Jungshik said in (id=140013), if you require complete Tamil
support there are 2 options. 1- support OT or 2 - use the short-term converter
approach similar to Thai (tis620* or hindi (sun.unicode.india-0) approach). If
someone could volunteer to produce a shaper similar to pango shapers would be
happy to QA and integrate it. Until then it will remain as "future". If partial
(just rendering) support is needed, Jungshik's patch (id=122195) will help.

Comment 2

16 years ago
> Like bug 140013 but for Linux.

I've already filed bug 204039 as you know. If you want this bug to specifically
deal with Tamil
rendering with **opentype** layout tables, I think it's better to
make that clear in the summary line.

As  Prabhat wrote, just for rendering (within the limitation of TSCII fonts), my
patch
uploaded to bug 204039 would do it.

Prabhat, it seems like we have to find a way to invoke (as opposed to 
rolling out our own PangoLite in Mozilla) Pango APIs from nsFontMetricsXft.cpp (and
other places for editing/selectin/cursor....)  
Actually, the whole nsIFontMetrics interface can be written in terms of Pango APIs
(or Uniscribe APIs for nsFontMetricsWin and selection/editing in Mozilla-Windows).
It appeared that blizzard (see my and his comments in bug 176290) considered
that approach
but dropped it because Owen told him that Pango was rather slow. Nonetheless, he
agrees that
Pango is for complex scripts. If we can figure out a simple way to bridge Mozilla's 
nsFontMetricsXft (and other places for editing/cursor movement/selection, and so
forth) and Pango
(as installed as a system component) without going all the way to 'Pangozing'
nsFontMetricsXft 
(i.e.use Xft APIs for 'simple' scripts while invoking Pango APIs for complex
scripts)
it  would be a great boon for complex scripts. 
SILA project at <http://sila.mozdev.org> may shed some light on this. 
What would you say? 
(Reporter)

Comment 3

16 years ago
I would like the long term solution, i.e. use opentype tables.

How can I help? I do not know anything about opentype tables, cmaps, but if you
give me some pointers, maybe I can help.
Summary: Incorrect display of Tamil Unicode (problems in reordering/combining) → Fix Tamil rendering with **opentype** layout tables
(Reporter)

Updated

16 years ago
Summary: Fix Tamil rendering with **opentype** layout tables → Fix Tamil unicode rendering with **opentype** layout tables
(Reporter)

Comment 4

16 years ago
Created attachment 122249 [details]
Incorrect reordering/combining of tamil unicode.

Mozilla(Linux) displaying the below text using the Code2000 font. (As requested
by Mr. Srivas).

&#2980;&#3007;&#2992;&#3009;&#2997;&#2995;&#3021;&#2995;&#3009;&#2997;&#2992;&#3021;

&#2949;&#2994;&#3021;&#2994;&#2980;&#3009;
&#2997;&#3006;&#2996;&#3021;&#2965;&#3021;&#2965;&#3016;
&#2997;&#3007;&#2995;&#2965;&#3021;&#2965;&#2990;&#3021;

&#2949;&#2993;&#2980;&#3021;&#2980;&#3009;&#2986;&#3021;&#2986;&#3006;&#2994;&#3021;

&#2950;&#2991;&#3007;&#2992;&#2965;&#3021;&#2965;&#2979;&#2965;&#3021;&#2965;&#3006;&#2985;

&#2965;&#3007;&#2995;&#3016;&#2965;&#2995;&#3016;&#2991;&#3009;&#2990;&#3021;
&#2997;&#3007;&#2996;&#3009;&#2980;&#3009;&#2965;&#2995;&#3016;&#2991;&#3009;&#2990;&#3021;

&#2953;&#2975;&#3016;&#2991; &#2950;&#2994;&#3021;
&#2990;&#3009;&#2980;&#2994;&#3007;&#2991;
&#2990;&#2992;&#2969;&#3021;&#2965;&#2995;&#3016;&#2997;&#3007;&#2975;,
&#2984;&#3009;&#2975;&#3021;&#2986;&#2990;&#3006;&#2985;
&#2953;&#2993;&#3009;&#2986;&#3021;&#2986;&#3009;&#2965;&#2995;&#3016;
&#2953;&#2975;&#3016;&#2991;&#2997;&#2985;&#3006;&#2991;&#3021;
&#2984;&#3010;&#2993;&#3006;&#2991;&#3007;&#2992;&#2965;&#3021;&#2965;&#2979;&#2965;&#3021;&#2965;&#3006;&#2965;&#2980;&#3021;
&#2980;&#2990;&#3021; &#2951;&#2985;&#2980;&#3021;&#2980;&#3016;&#2986;&#3021;
&#2986;&#3014;&#2992;&#3009;&#2965;&#3021;&#2965;
&#2997;&#2994;&#3021;&#2994;&#2985;&#2997;&#3006;&#2991;&#3021;
&#2953;&#2995;&#3021;&#2995;
&#2970;&#3007;&#2993;&#3021;&#2993;&#3009;&#2991;&#3007;&#2992;&#3021;&#2965;&#2995;&#3016;&#2997;&#3007;&#2975;,

&#2951;&#2992;&#2997;&#3009;&#2990;&#3021;
&#2986;&#2965;&#2994;&#3009;&#2990;&#3021; &#2963;&#2991;&#3006;&#2980;&#3009;
&#2953;&#2996;&#3016;&#2965;&#3021;&#2965;&#2997;&#2994;&#3021;&#2994;
&#2958;&#2993;&#3009;&#2990;&#3021;&#2986;&#3009;
&#2990;&#3009;&#2980;&#2994;&#3007;&#2991;&#2997;&#2993;&#3021;&#2993;&#3016;&#2997;&#3007;&#2975;,
&#2958;&#2969;&#3021;&#2965;&#3009;&#2990;&#3021;
(Reporter)

Comment 5

16 years ago
Created attachment 122251 [details]
Same text using the TSCu_Paranar.ttf font

Comment 6

13 years ago
Please recheck this bug against a recent nightly build[1] to verify that the
behavior still exists and post the results here.

Thanks.

[1] ftp://ftp.mozilla.org/pub/mozilla.org/firefox/nightly/latest-mozilla1.8/
No reply to comment #6 since 2005-09-06 => INCOMPLETE.

Reopen if you can reproduce this bug on a recent build (and say which build).
Status: UNCONFIRMED → RESOLVED
Last Resolved: 11 years ago
Resolution: --- → INCOMPLETE

Updated

10 years ago
Component: Layout: CTL → Layout: Text
QA Contact: arthit → layout.fonts-and-text
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