[USE] Missing CONS_MED subclasses for some Indic_Positional_Category values #928
Description
Not all values of Indic_Positional_Category are accounted for when assigning characters to the subclasses of CONS_MED.
The only CONS_MED in [:InPC=Bottom_And_Left:] is U+A9BF JAVANESE CONSONANT SIGN CAKRA. IndicPositionalCategory-Additional.txt overrides it to Bottom. It would be more future-proof to change the USE spec to map that position to CONS_MED_BELOW and remove the override.
The only CONS_MEDs in [:InPC=Bottom_And_Right:] are U+A9BE JAVANESE CONSONANT SIGN PENGKAL and U+11942 DIVES AKURU MEDIAL RA. IndicPositionalCategory-Additional.txt overrides them to Right. It would be more future-proof to change the USE spec to map that position to CONS_MED_POST and remove the overrides.
The only CONS_MEDs in [:InPC=Top_And_Bottom_And_Left:] are U+103C MYANMAR CONSONANT SIGN MEDIAL RA and U+1171E AHOM CONSONANT SIGN MEDIAL RA. IndicPositionalCategory-Additional.txt overrides U+103C to Left. U+1171E is unaccounted for, so the USE spec does not specify what to do with it. HarfBuzz treats Top_And_Bottom_And_Left the same as Left. The USE spec should map that position to CONS_MED_PRE and remove the override.
Document Details
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- ID: 194a6d3c-4137-46e9-3a4b-44b990200986
- Version Independent ID: a0c8e788-5228-aa28-670e-3ba1ac3faecd
- Content: Creating and supporting OpenType fonts for the Universal Shaping Engine - Typography
- Content Source: typographydocs/script-development/use.md
- Product: typography
- GitHub Login: @Anglass
- Microsoft Alias: anglass