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Bug 318881

Summary:	[bidi] Bidi layout transformation engine
Product:	[Eclipse Project] Platform	Reporter:	Tomer Mahlin <tomerm>
Component:	SWT	Assignee:	Platform-SWT-Inbox <platform-swt-inbox>
Status:	CLOSED WONTFIX	QA Contact:
Severity:	normal
Priority:	P3	CC:	camle, daniel_megert, deepakazad, fira, kitlo, Lina.Kemmel, markus.kell.r, matial, Mike_Wilson, peter, pwebster, sadir, semion
Version:	3.7
Target Milestone:	---
Hardware:	PC
OS:	Windows Server 2003
Whiteboard:	stalebug

Description Tomer Mahlin

2010-07-05 07:47:51 EDT

Build Identifier:

What is it ?
--------------
Bidi layout engine (or Bidi engine) transforms text from one Bidi layout to another Bidi layout in accordance with Bidi Unicode algorithm. For more info on Bidi Unicode algorithm please read following article: http://unicode.org/reports/tr9/

Why do we need it ?
--------------------
Bidi engine is used in many contexts when change in attributes of Bidi text is required. For example in transforming Bidi text from visual Bidi layout to logical Bidi layout (e.g. DTP).

What is currently available ?
-------------------------------
Currently Eclipse is packaged with following main Bidi engines:
1. IBM Bidi engine available from IBM JDK: com.ibm.bidiTools.bdlayout.*
2. Bidi engine from ICU4J (http://site.icu-project.org/): com.ibm.icu.text.Bidi
3. Bidi engine available from JDK: java.text.Bidi

In terms of functional completeness the main Bidi engines of interest are that of IBM JDK and ICU4J.

What is missing ?
------------------
Eclipse can't depend on IBM JDK. This is because it also support other JDK and since Bidi engine is not available in IBM JDK for all platforms (it is available for Windows, Linux but not on HP-UX, Sun etc.).
ICU4J Bidi engine is less functional than that of IBM JDK (lacks of several important features) and less convenient for usage.

What can be done ?
-------------------
Basically we have following options:
1. Enhance ICU4J Bidi engine to match the level of IBM JDK Bidi engine
2. Provide the enhancements for ICU4J Bidi engine on the Eclipse level
3. Adopt another version of Bidi engine. For example, JTOpen (http://jt400.sourceforge.net/) Bidi engine: com.ibm.as400.access.Bidi*
4. Develop brand new implementation of Bidi engine in Eclipse.

Reproducible: Always

Comment 1 Dani Megert

2010-07-05 08:25:27 EDT

Without any usage in the SDK it seems wrong to add it here (option 2). I think the right approach is to go with 1. and offer the bundle via Orbit, so that interested parties can take and include it from there.

At any rate Platform Text is too high in the stack. This rather belongs to either SWT or Equinox Components where the enhanced TextProcessor will be hosted. Trying SWT for now, but as said, this is rather a bug for Orbit and ICU4J.

Comment 2 Tomer Mahlin

2010-07-05 08:34:44 EDT

The originally opened defect was a transcript of idea voiced out by Lina. I believe Lina is planning to open a separate bug in which she will share her perspective on the problem. Thus, I am closing this bug as irrelevant.

Comment 3 Tomer Mahlin

2010-09-14 05:43:06 EDT

Just wanted to provide an update on the progress made in this context. Most prominent and also cheap direction to proceed with seems to be option 1 (work with ICU). We are currently checking with ICU if it is possible to provide the enhancement of Bidi engine as part of ICU itself or as a separate ICU dependent package. If latter option is chosen, we will need to pack this separate package with Eclipse (or via Orbit). Thus I prefer to keep this defect open for the time being.

Comment 4 Eclipse Genie

2019-11-20 16:53:04 EST

This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet.

If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

--
The automated Eclipse Genie.

Comment 5 Dani Megert

2019-11-21 10:11:34 EST

Tomer, do you still want this to be kept open? Nothing will happen in the near future here.