'ss05' renders vowel signs with /rya/ incorrectly

[mandel59]

Defect Report

Title

'ss05' renders vowel signs with /rya/ incorrectly

Font

NotoSansSiddham-Regular.ttf

Where the font came from, and when

Site: https://github.com/notofonts/siddham/releases/tag/NotoSansSiddham-v2.003 Date: 2022-09-15

Font Version

Version 2.003

OS name and version

macOS Monterey version 12.6

Application name and version

hb-view, Firefox

Issue

'ss05' alters the form of the /rya/ character, but vowel signs are not alterd and rendered incorrectly.

Character data

Characters rya ryā ryi ryī ryu ryū rye ryo:

𑖨𑖿𑖧𑖨𑖿𑖧𑖯𑖨𑖿𑖧𑖰𑖨𑖿𑖧𑖱𑖨𑖿𑖧𑖲𑖨𑖿𑖧𑖳𑖨𑖿𑖧𑖸𑖨𑖿𑖧𑖺

U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115AF SIDDHAM VOWEL SIGN AA
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115B0 SIDDHAM VOWEL SIGN I
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115B1 SIDDHAM VOWEL SIGN II
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115B2 SIDDHAM VOWEL SIGN U
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115B3 SIDDHAM VOWEL SIGN UU
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115B8 SIDDHAM VOWEL SIGN E
U+115A8 SIDDHAM LETTER RA
U+115BF SIDDHAM SIGN VIRAMA
U+115A7 SIDDHAM LETTER YA
U+115BA SIDDHAM VOWEL SIGN O

Screenshot

Harfbuzz hb-view rendering

hb-view --font-file=NotoSansSiddham-Regular.ttf --features=ss05 --text-file=input.txt --output-file=out.png

Firefox

Rendered with Bonji Input (https://mandel59.github.io/bonji-input/)

[simoncozens]

I've made ss05 do something vaguely sensible with ryu, but I feel like there's not much to distinguish between ryu with ss05 and ryu with ss01.

Default:

ss05:

ss01: