TTA-RA conjunct needs redrawing

[KazunariTsuboi]

Font

NotoSansBengali-*
All NotoSans Bengali fonts

Where the font came from, and when

https://github.com/googlefonts/noto-fonts/tree/main/hinted/ttf/NotoSansBengali　
Date: 2021/3/1

OS name and version

Windows 10 1909

Application name and version

Google Chrome 89.0.4389.90

Issue

Noto Sans Bengali does not display the TTRA character as a ligature.
The character form in NotoSerifBengali and prior version of NotoSansBengali had the character displaying correctly.
According to our records the version 2.000 (2017/9/20) had the character form as the following:
https://github.com/googlefonts/noto-fonts/blob/bc9353da6f625b7a47035de952c2e8fd9e3ae889/hinted/NotoSansBengali-Regular.ttf

However, in Version 1.03 (2015/9/26), the font displays the character as a ligature as the following:
https://github.com/googlefonts/noto-fonts/blob/ad153f5a14c838afb16c83f0a02784c7605f1e21/hinted/NotoSansBengali-Regular.ttf

On the other hand, the Noto Serif fonts display the ligature correctly.

Character data

ত্ত্র
U+09A4, TA
U+09CD, VIRAMA
U+09A4, TA
U+09CD, VIRAMA
U+09B0, RA

Harfbuzz hb-view and hb-shape

[tabeng=0+707|viramabeng=0@-108,0+0|tarabeng=2+715]

[sridatta1]

I think this issue can be reopened
In many printed books which I hav come across, ttra is written in as a ligature with the following form

(https://archive.org/details/bengaligrammar00wenggoog/page/n24/mode/1up)

(https://access.bl.uk/item/viewer/ark:/81055/vdc_100086181011.0x000001#?c=0&m=0&s=0&cv=30&xywh=1105%2C613%2C2070%2C1296)

পুত্ত্র পৌত্ত্র
( book link )
glyph in some other fonts of fonts.google.com

[simoncozens]

I'm not sure we need to reopen - what's wrong with the fix?

[sridatta1]

I mean in the printed books which I have seen, including Vidyasagar's Varnaparicaya which is one of the basis for Modern Bengali typesetting. The glyph of ttra ত্ত্র is different from what is proposed here.



Glyph which is proposed here by the issue raiser

[simoncozens]

Oh, huh, so it needs re-drawing. Understood.