Indy3! Indic scripts through USE shaper #539
Description
Support 'xxx3' script tags for Indic scripts through USE shaper. Apple does that and we want to put it in OpenType itself. According to Ned, here's the overrides they use:
# Indic_Syllabic_Category=Nukta
0F71 ; Nukta # Mn TIBETAN VOWEL SIGN AA
# ================================================
# Indic_Syllabic_Category=Tone_Mark
1CED ; Tone_Mark # Mn VEDIC SIGN TIRYAK
A982 ; Tone_Mark # Mn JAVANESE SIGN LAYAR
# ================================================
# Indic_Syllabic_Category=Consonant_Dead
0F7F ; Consonant_Dead # Mc TIBETAN SIGN RNAM BCAD
# ================================================
# Indic_Syllabic_Category=Symbol_Combining
1B6B..1B73 ; Symbol_Combining # Mn [9] BALINESE MUSICAL SYMBOL COMBINING TEGEH..BALINESE MUSICAL SYMBOL COMBINING GONG
# ================================================
# Indic_Syllabic_Category=Cantillation_Mark
1CE2..1CE8 ; Cantillation_Mark # Mn [7] VEDIC SIGN VISARGA SVARITA..VEDIC SIGN VISARGA ANUDATTA WITH TAIL
# ================================================
# Indic_Syllabic_Category=Consonant
A8F2..A8F7 ; Consonant # Lo [6] DEVANAGARI SIGN SPACING CANDRABINDU..DEVANAGARI SIGN CANDRABINDU AVAGRAHA
A8FB ; Consonant # Lo DEVANAGARI HEADSTROKE
A8FD ; Consonant # Lo DEVANAGARI JAIN OM
# Indic_Positional_Category=Top
0F74 ; Top # Mn TIBETAN VOWEL SIGN U
1A18 ; Top # Mn BUGINESE VOWEL SIGN U
1B6B ; Top # Mn BALINESE MUSICAL SYMBOL COMBINING TEGEH
1B6D..1B73 ; Top # Mn [7] BALINESE MUSICAL SYMBOL COMBINING KEMPUL..BALINESE MUSICAL SYMBOL COMBINING GONG
# ================================================
# Indic_Positional_Category=Bottom
0F72 ; Bottom # Mn TIBETAN VOWEL SIGN I
0F7A..0F7D ; Bottom # Mn [4] TIBETAN VOWEL SIGN E..TIBETAN VOWEL SIGN OO
0F80 ; Bottom # Mn TIBETAN VOWEL SIGN REVERSED I
1B6C ; Bottom # Mn BALINESE MUSICAL SYMBOL COMBINING ENDEP
We should probably also move our overrides to data files instead of Python or C code!