On 16 August 2015 at 23:50, Richard Wordingham <richard.wording...@ntlworld.com> wrote: > >> @+ For details about the implementation of variation sequences in >> Phags-pa, please refer to the Phags-pa section of the core >> specification. > > a) This is likely to be ignored by someone who is just looking for the > *specification*. I think replacing 'implementation' by 'rendering' > would be better. I would be inclined to add, 'These sequences are more > complicated than they appear at first reading'. Otherwise, someone > will just add them to the character to glyph conversion section of a > font and think, "Job done".
That's not a plausible scenario. Phags-pa has complex shaping and joining requirements, and it is impossible for someone to create a properly functioning Phags-pa font based on the code charts alone. If anyone did implement Phags-pa in a font based solely on the Unicode or 10646 code charts, with no joining or shaping behaviour, for use as a fallback font or as a code chart font then naively implementing U+A856 + U+FE00 (VS1) as a mirrored glyph is not unreasonable. If they want to produce a Phags-pa font for displaying running Phags-pa text then at a minimum they will need to read the appropriate section of the core specification. Andrew