> On Feb 18, 2018, at 3:26 , Khaled Hosny via Unicode <unicode@unicode.org> > wrote: > > On Sun, Feb 18, 2018 at 02:14:46AM -0800, James Kass via Unicode wrote: >> Adam Borowski wrote, >> >>> I'm looking for a way to determine a font's coverage of available scripts. >>> It's probably reasonable to do this per Unicode block. Also, it's a safe >>> assumption that a font which doesn't know a codepoint can do no complex >>> shaping of such a glyph, thus looking at just codepoints should be adequate >>> for our purposes. >> >> You probably already know that basic script coverage information is >> stored internally in OpenType fonts in the OS/2 table. >> >> https://docs.microsoft.com/en-us/typography/opentype/spec/os2 >> >> Parsing the bits in the "ulUnicodeRange..." entries may be the >> simplest way to get basic script coverage info. > > Though this might not be very reliable since OpenType does not have a > definition of what it means for a Unicode block to be supported; some > font authoring tools use a percentage, others use the presence of any > characters in the range, and fonts might even provide incorrect data for > any reason. > > However, I don’t think script or block coverage is that useful, what > users are usually interested in is the language coverage. > > Regards, > Khaled
All true. In addition, ulUnicodeRange ran out of bits around Unicode 5.1, so scripts/blocks added to Unicode after that, such as Javanese, Tangut, or Adlam, cannot be represented. Norbert
