Unicode - AAT vs OT fonts in Revolution

[Sivakatirswami]

I'm interesting in deploying some apps that use Devanagiri and Tamil 
Unicode text, and making them appear correctly on both Windows and 
Apples machines.

I'm just beginning the foray into the unicode world in InDesign after 
waiting for several years for InDesign to get up to speed. Today it has, 
well, almost. By using IndicPlus plug in, (fabulous and only $20.00) we 
can now display OT (Open Type) unicode Indic fonts in InDesign.

But of course, I want to use RunRev Stacks -- it's more fun for users... 
(smile)

The issue will be: Apple's use of the Atsui rendering engine which will 
only properly display AAT unicode fonts (Apple Advance Typographical) 
fonts. Meanwhile on Windows uses its own rendering engine and unicode 
fonts must have OT Tables. At the Mac developer conference recently, one 
top IT man from Malaysia who was there said that Apple will probably not 
move form it's position in sticking with AAT fonts, and for good reason. 
Apparently Window messed up with OneScribe engine and now users are 
having trouble (it works one way on XP, another on Vista and some valid 
OT fonts are not rendering properly at all on Vista). Meanwhile Adobe 
has clearly made decision to write code for windows first and mac 
second, and for some reason obstinately continues to lag behind in the 
rendering of AAT fonts, even when Windows is starting to... end of sob 
story... some of you must know it well already.

My assumption is: and please correct me if I am wrong: Revolution will 
use the Atsui engine on the Mac to render Unicode fonts and therefore, 
only AAT fonts will display properly. Meanwhile, that same stack, if it 
were put on a  Windows machine, will only work by calling a different OT 
unicode font. Second assumption is that the work around for dealing with 
this incompatibility issue would be to check for the platform and then 
call a different font for the fields being use to display text. This 
assumes that the unicode will be the same regardless of the font or 
rendering environment.

but then, we have the old problem: will the user have the necessary 
fonts on his system? Ideally we could carry the fonts in the stacks 
themselves, but my understanding is that Rev embedded font capability is 
limited to True Type fonts and not AAT fonts or OT fonts. So it will 
mean either storing a font in a custom prop and then offering it to the 
user to install (one for Mac and one for Win)  or send them URL's with 
instructions to download and install those fonts.

I'm hoping I'm wrong about this and that before I go down that road, 
someone will tell us what brilliant solution they have for dealing with 
this in Revolution. For Japanese, Chinese someone must have faced all 
these issues already.

Danyavad - Thank you
Sivakatirswami