[XeTeX] Microtypography?

[Geoffrey Alan Washburn]

Jonathan Kew wrote:

> Possibly, but it'll be very different from pdfTeX's implementation.  
> In the non-Roman world, there's no assurance that the first  
> *character* on a line (which is the "addressable unit" in terms of  
> TeX's processing of the text) will actually fall at the visual  
> edge.... glyph reordering in Indic scripts, for example, break this  
> assumption. So when considering line-break positions, it may not be
> 
> Of course, we also can't express amounts of protrusion in terms of  
> characters, as a given character may be rendered by very different  
> glyphs in different contexts. So the whole paragraphing algorithm  
> will have to be much more aware of the two-level character/glyph  
> model than it is at present; right now, XeTeX works in terms of  
> characters, and the details of individual glyphs are largely hidden  
> by the rendering technology (ATSUI or ICU/OpenType).
> 
>> but support for
>> expansion/shrinking of glyphs could be quite complex depending upon  
>> the
>> rendering API you have available.
> 
> Actually, that's probably the easier part, as it can be done by  
> manipulating the transform matrix through which the text is rendered;  
> at least, for uniform expansion/shrinking of all the glyphs in a run  
> of text.

	Interesting.  I guess it goes to show how intuition isn't
always very good at picking out what will be easy and what will be
difficult.

> Before thinking of anything new, be sure to look closely at not only  
> Multiple Masters (which Adobe has largely abandoned)

	Yes, I've never worked with them, but some of my ideas are partly
inspired about what I've read about them.

> but also Apple's 'glyph variation' technology and other aspects 
> of AAT. There's a lot of cool stuff in there, at least in the
> design and the low-level implementation, but it hasn't been
> widely adopted either by font vendors or application developers.

	Is there a good reference you can point me to?

	I should probably actually look at some of the material on Graphite.