In traditional Malayalam orthography, the vowel sound /au/ is represented by a two-part vowel sign . In modern ways of writing Malayalam (including the official reformed orthography) the vowel sound /au/ is represented by a single part vowel sign which looks like the right part alone: .
Unicode encodes U+0D4C MALAYALAM VOWEL SIGN AU and U+0D57 MALAYALAM AU LENGTH MARK. The latter was encoded with the intent that it represent a glyph for the right half of U+0D4C. This mark U+0D57 happens to correspond to the representation of the sound /au/ in the modern orthography.
The question for public input is which of the following two options should be recommended:
Option A: The modern orthography would use U+0D57 for /au/. Under this option, both orthographies can be represented in the same font, but the spelling of /au/ would change when switching between orthographies.
Option B: Text in the modern orthography would use U+0D4C for /au/. Any such text would require a distinct font to display a one-part sign for the modern orthographic appearance. Thus the same spelling would be used for both orthographies, requiring a change in font to display text in one style or the other.
Points to be considered by reviewers: