A similar issue to the nndda: starting on page 54 of the TDIL newsletter (http://tdil.mit.gov.in/ori-guru-telu.pdf) and continuing onto the next page, they list conjuncts that have BA or WA as the second element. I've shown those from the bottom of p. 54 in the attached image.
The shape for the conjoined component is the same for both of these.
They describe the first as involving BA, however, while all the others
involve WA. The question, then, is how "MBA" should be encoded: as <0B2E MA, 0B4D VIRAMA, 0B2C BA >, or as < 0B2E MA, 0B4D VIRAMA, 0B71 WA>?
I think the TDIL chart is wrong.
Traditionally (as in Learn Oriya in 30 Days) subjoined BA is used in this context although the reading rules say to pronounce it [w]. Examples from this book:
k. + ba (wa) = kwa j. + ba (va) = jva dh. + ba (wa) = dhwa m. + ba = mba r. + ba = rba sh. + ba = shba
Now an original ligature of O and BA has been pressed into service as a syllable initial WA for foreign words, and encoded at U+0B71, but I do not think this should be used to form conjuncts in -[wa].
o + ba (wa) = wa (this is not an example in Learn Oriya in 30 Days)
The traditional BA should be used for that unless we have better evidence than the TDIL newsletter that such should be the practice.
[mba] and an eventual [mwa] would be encoded MBA and the reading rule would be learned.
So I don't think that ORIYA LETTER WA has a conjunct form identical with ORIYA LETTER BA in the same way that DDA and TA do.
Michael Everson * * Everson Typography * * http://www.evertype.com