[XeTeX] Feedback on W32 Port of XeTeX v0.994

[Jonathan Kew]

On 13 Jun 2006, at 12:43 pm, Jonathan Kew wrote:

> On 13 Jun 2006, at 10:21 am, Toralf Senger wrote:
>
>> Last issue I noticed: Independant of how I inlcude the font (with
>> fontspec, \font= or with my stylefile), the pnum feature
>> (Proportional Figures) gave a strange result: when I type several
>> times the nunber 'one', like 11111111, they end up in visualy quite
>> disturbung groups of two digits, like 11 11 11 11..not separeted by
>> much, but still quite visible. Other Opentype aware applications
>> like Adobe Indesign or Illustrator dont to that and neither does
>> PDFTex do that..so is this a bug or a feature (the result of the
>> script that is behind pnum)?
>
> I've done some investigation, and this appears to be caused by a bug
> in the ICU layout implementation of OpenType kerning (which is used
> internally to support the proportional digit spacing in Adobe's
> fonts). Alternate kerns in a sequence are skipped. :(
>
> You can demonstrate a similar effect by using Latin Modern and
> comparing "AV", "VA", "AVAVAV", and "VAVAVA".

The code in the xetex subversion repository now includes a fix for  
this bug (also reported to the ICU project); it seems to work  
correctly for me on Mac OS X now, but has not been tested extensively  
yet.

I'd like to look into the optical sizing issue as well, before  
considering a new release, but in the meantime anyone who would like  
to build the code from TRUNK and test this is welcome to give it a try.

JK