Philippe Verdy wrote:
What's uncertain is whether a lr or a rl progression is favored, given the
paucity of evidence. Michael favors lr progression. There is no question
that the text is read BTT.
This creates an interesting problem: Put in the same sentence Han (Chinese) and
Mongolian words in a vertical layout (I don't think this is unlikely, as
Mongolian is also spoken in China, and there's also a Chinese community in
Mongolia). So Chinese ideographs will be laid out vertically from top to bottom
(but not rotated, except for a few characters like ideographic punctuation marks
or symbols), and Mongolian will be laid out from bottom to top in their normal
stack orientation. Such a text is clearly bidirectional, so we would need BiDi
processing to order glyphs correctly.
I don't understand this scenario. Mongolian is laid out from top to bottom when
in vertical lines, *always*. /Ogham/ is what would go bottom to top, and yes,
that would create a different BIDI scenario than that found in horizontal text.
So what is shown here is that Bidi properties are only accurate for horizontal
flows of text. What is missing is a separate set of Bidi properties for the
vertical direction of the same flow... We could define basically a similar
algorithm for vertical BiDi, but this would also require new BiDi properties.
This is what I've tried to argue, but for different script combinations than
you are describing here: the directions of Mongolian and Han do not conflict
in vertical text.
~fantasai
--
http://fantasai.inkedblade.net/contact
