On 13-04-22 09:16 PM, suzuki toshiya wrote: > Dear Behdad, > >> Though, we still have to assess what >> effect it would have on fonts that implement variation-selectors via GSUB >> instead of cmap. Does anyone know any fonts like that? > > Maybe some Mongolian fonts have VS to be handled via GSUB, > instead of cmap format 14 (because Mongolian VS were standardized > before cmap format 14). Please let me know what I should > check in detail.
Thanks. If you come across them, please send me a note. Otherwise no need to go looking right now. Cheers, behdad > Regards, > mpsuzuki > > Behdad Esfahbod wrote: >> On 13-04-22 08:20 PM, Khaled Hosny wrote: >>> On Sat, Apr 20, 2013 at 10:49:26AM +0100, Jonathan Kew wrote: >>>> On 19/4/13 22:13, Behdad Esfahbod wrote: >>>> >>>>> - What should HB_BUFFER_FLAG_PRESERVE_DEFAULT_IGNORABLES do to variation >>>>> selectors? Right now they do not become visible no matter what. Is it >>>>> relevant whether the variation selector was actually used during glyph >>>>> lookup >>>>> or not? >>>> Yes, I think it's relevant. A variation selector that was used >>>> during glyph lookup has (in a sense) become "visible", manifested as >>>> a particular choice of glyph. I don't think it should -also- appear >>>> as a separate glyph, even in a "show invisibles" mode. In effect, >>>> the <base, VS> pair has been ligated - it's just a "ligation" that's >>>> handled by the cmap instead of GSUB. >>> But this can be said about many other control characters, ZWJ or ZWNJ >>> for example, they have a visual effect. >>> >>> IMO PRESERVE_DEFAULT_IGNORABLES should simply show any default ignorable >>> character that is being removed from the output not as a result of >>> OpenType glyph substitution. One use of such feature (the only use?) is >>> to make visible all characters that has mysterious effects on the output >>> so they can be easily checked/edited, and I can see variation selectors >>> benefiting from this just like any other default ignorable. >> >> >> Note that if the font has a lookup ligating with ZWJ / ZWNJ (or any other >> default-ignorable) those won't be display even with >> PRESERVE_DEFAULT_IGNORABLES either. We have to go out of our way to make >> that >> happen (may be very hard for GSUB). It just happens that for >> variation-selectors it may be easier. Though, we still have to assess what >> effect it would have on fonts that implement variation-selectors via GSUB >> instead of cmap. Does anyone know any fonts like that? >> >> behdad >> >>> Regards, >>> Khaled >>> _______________________________________________ >>> HarfBuzz mailing list >>> [email protected] >>> http://lists.freedesktop.org/mailman/listinfo/harfbuzz >>> >> > > -- behdad http://behdad.org/ _______________________________________________ HarfBuzz mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/harfbuzz
