Javanese: Positioning and shaping broken with dotted circle as base

Font

NotoSansJavanese-Regular.ttf

Where the font came from, and when

https://github.com/googlei18n/noto-fonts/blob/master/phaseIII_only/unhinted/ttf/NotoSansJavanese/NotoSansJavanese-Regular.ttf 2019-03-24

Font Version

2.000

OS name and version

macOS 10.13.6

Application name and version

Safari 12.0.3 Firefox 66.0.1

Issue

When text contains a dotted circle, or a dotted circle has been inserted by the shaping engine, marks are positioned in places that seem haphazard, and cakra is neither reordered to before the dotted circle nor ligated with vowels and pasangan that it ligates with in other contexts.

Dotted circle is commonly used as a base when writing about a script or on keyboards, and should therefore be treated as a first class citizen.

Steps to reproduce

Go to: https://lindenbergsoftware.com/google/noto/java-shaping.html and look at the section “Dotted circle as base”.

Observed results

Panyangga and suku are positioned towards the right above the dotted circle.

Cakra is positioned on the right of dotted circle, and doesn’t form ligatures with vowels or pasangan.

Expected results

Panyangga and suku should be positioned centered above the dotted circle.

Cakra should be positioned to the left of dotted circle, and form ligatures with vowels or pasangan if it would do so when combined with consonants as a base.

Additional information

The same test case rendered with the Yogya font, which is available as part of the Javanese Font and Keyboard app for iOS:

notofonts / javanese