740161 - Rendering issue for devanagari

Status: NEW

(Core :: Layout: Text and Fonts, defect)

Description

[शंतनू]

Attachment: Silpa- The Indian Language Computing project.jpg

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:11.0) Gecko/20100101 Firefox/11.0
Build ID: 20120310173008

Steps to reproduce:

Typed र्‍या and र्‍ह



Actual results:

Rendering is not correct.
र्‍या and र्‍ह is rendered as ऱ्या and ऱ्ह respectively. 


Expected results:


It should have been rendered as follow
silpa.org.in/Render?text=र्‍या%20र्‍ह 
And not as 
silpa.org.in/Render?text=ऱ्या%20ऱ्ह

Comment 1

[Jonathan Kew [:jfkthame]]

To clarify, as how the Devanagari text in comment #0 appears will be dependent on the OS, browser and fonts being used to view the bug report, the issue here is that a sequence such as

  U+0930 RA, U+094D VIRAMA, U+200D ZWNJ, U+092F YA, U+093E AA-MATRA

is being rendered identically to

  U+0931 RRA, VIRAMA, YA, AA-MATRA

with both generating the glyph sequence

  eyelash-ra, ya, aa-matra

whereas the first sequence *should* render the glyphs

  ra, halant, ya, aa-matra

Comment 2

[Jonathan Kew [:jfkthame]]

Note that this is occurring on OS X, using the Devanagari MT font, which means we're using the Core Text codepath.

What puzzles me is that I don't see the same behavior with Devanagari MT in other applications such as TextEdit. Possibly a discrepancy between Core Text and Cocoa Text?