On Fri, Feb 12, 2010 at 07:21:14PM +0100, Hans Hagen wrote: > On 12-2-2010 19:03, Khaled Hosny wrote: > >Is 'opbd' feature supported? According to the spec[1] this feature is > >used to define what I think is equivalent to the protrusion values used > >for optical alignment of the glyphs. I grepped the sources and there > >seem no be special handling of it, I don't have fonts that use this > >feature (I didn't look for one) but I'm planning to use it in my fonts > >and thought I'd check if ConTeXt support it first. > > > >This Typophile thread[2] might be interesting too. > > > >If fonts are needed I can check for free fonts that implement this, or > >prepare a font for testing. > > > >[1] http://www.microsoft.com/typography/OTSPEC/features_ko.htm#opbd > >[2] http://typophile.com/node/48738 > > Indeed I need a test font in order to see how it can be implemented. > If there are no fonts we should wonder what the exact spec is. Does > fontforge support it?
I found that the font "fxlbi.otf" (of libertine fonts) has both 'lfbd' and 'rtbd' (left/right optical bounds) but no 'opbd' feature. Now re-reading the spec, I don't see what the values stored in 'opbd' is used for as the application has to consult 'lfbd' or 'rtbd' feature according to the position of the glyph in the line, I asked on OpenType mailing list but I don't expect getting an answer (nobody implemented this feature, except FontForge AFAIK.) My suggestion is to ignore 'opbd' completely and just use the values from 'lfbd'/'rtbd' directly. Regards, Khaled -- Khaled Hosny Arabic localiser and member of Arabeyes.org team Free font developer _______________________________________________ dev-context mailing list dev-context@ntg.nl http://www.ntg.nl/mailman/listinfo/dev-context
