Re: FVS Assignment Mismatch WrapUp - Definition of Toggling

On Mon, 31 Aug 2015 07:05:28 +0100
Richard Wordingham <richard.wordingham@ntlworld.com> wrote:

> == Override ==

<snip>

> At stage B, the cmap is consulted and they are converted to glyphs as
> follows:
> 
> 1828      > gN0id
> 1828 180B > gN1m
> 1828 180C > gN2m

I got confused with the proposals being discussed here.  GB/T 26226 has
1828 180D to force the medial form to be undotted, so please read
the last line above as

1828 180D > gN3m.

and all occurrences of gN2m as gN3m.

<snip>

> At the end of stage D, we have to resolve the conflict between Tables
> A and B. If we assume the rendering engine will only look at a
> sequence of Mongolian, inherited and common characters, we could have
> something like a pair of contexts
> 
>  _ mong_shape
>  mong_shape _
> 
> where mong_shape is the set of glyphs from Mongolian script characters
> that are (dual) joining or join-causing.
> 
> and a consequential substitution
> 
> gN2m > gN0mu # Undotted medial form

This conflict does not occur.  The conflict for gN3m is with the
'separate form', which looks rather like nirugu followed by dotted
medial NA.  It may be that in connected text, it should rather be
encoded as <NIRUGU, NA> or <NIRUGU, NA, FVS1>, in which case the
OT rules should be:

If in either of contexts

  _ mong_shape
  mong_shape _

apply

  gN3m > gN3m # Some renderers insist that contexts have changes.

else

  gN3m > gN0mu

endif

An alternative interpretation is that is impossible to comply with GB/T
26226-2010.

====
I apologise for the misreading.

Richard.

Received on Monday, 31 August 2015 12:00:37 UTC