On Thu, May 2, 2013 at 2:28 AM, Richard Wordingham <[email protected]> wrote: > On Wed, 1 May 2013 15:50:54 +0700 > Theppitak Karoonboonyanan <[email protected]> wrote: > >> On Wed, May 1, 2013 at 2:39 PM, Richard Wordingham >> <[email protected]> wrote: > >> > (b) That word is not a problem for a Tai Khuen font. How should a >> > Lao Tham font handle it? > >> No need to handle it, because Mai Kang Lai is not that heavily used >> in Lao Tham. It should rather be spelt as ᩋᩢ᩠ᨦᨠᩕᩥ᩠ᩈ instead. > > That depends on whether one expects to have to choose the font > according to the spelling habits of the font. I would hope a font > could handle all the languages, though of cause it need not be beautiful > for all languages.
I've just recalled a style in a book, which has been mimicked in the attached image for "ᨸᩩᩕᩥᩈᩮᩣ" (puriso) in the first line. (I can take a photo of the evidence if you like.) So, I can imagine the rendering style for "ᩋᩘᨠᩕᩥ᩠ᩈ" as in the second line. >> > How would it handle the Pali word _sankilesa_ >> > spelt with MAI KANG LAI - I would expect text written for a Tai >> > Khuen font to use MAI KANG LAI. >> >> The conflict like this is usually avoided in Lao Tham manuscripts by >> using alternative spelling, probably ᩈᨦ᩠ᨠᩥᩃᩮᩈ. (I haven't found a real >> sample of this yet, >> just imply it from the tendency of other cases.) > > That is what I would expect - but see my comment above. Possibly a Lao > Tham font could protect itself by adding GSUB rules such as > > <KA, MAI KANG LAI> becomes <NGA, <SAKOT KA>> before SIGN I, though > the rearrangement is not nice. Perhaps the solution for a Lao Tham font > is a special <KA, MAI KANG LAI> ligature that looks very like <NGA, > SAKOT, > KA>. Or just cram the two marks into one column. It's already needed for the word "ᩈᩘᨥᩴ" (sangkhang). >> > (i) ᩁᩘᩈᩦ <RA, MAI KANG LAI, SA, SIGN II> 'ray of light' >> > (ii) ᩈᩘᨠᩕᩣᨶ᩠ᨲᩴ <HIGH SA, MAI KANG LAI, HIGH KA, MEDIAL RA, AA, NA, >> > SAKOT, HIGH TA, RA HAAM> 'songkran' > >> So, the question is for Lanna. Do such spellings exist, and how are >> they handled? If they exist, yes, the rendering engine 'must' handle >> it. > > The problem with handling the differences when reordering is that Lao > Tham reorders <MAI KANG LAI, HIGH KA, MEDIAL RA>, but the MFL style > does not. This gives us at least three different reordering behaviours. Three? Shift, no shift, and what else? > As to whether these spellings exist, I wish I had manuscript evidence. > >> > I'm still some way >> > from being ready to test the ability of GPOS to undo shaping. The >> > sort of GPOS rule I have in mind is: > >> > Context (lookup type 7): consonant consonant <MAI KANG LAI> >> > Lookup for context: At position 0, mark to base (lookup type 4), >> > skipping bases and other marks, to position MAI KANG LAI on the >> > consonant. > >> > In example (i) above, rearrangement would deliver <g(RA), g(SA), >> > g(MAI KANG LAI), g(SIGN II)>, and we need to be able to attach MAI >> > KANG LAI to RA. I don't know if this sort of rule works. >> >> I think having the rendering engine do it should be simpler. > > The problem is that the reordering logic is not very flexible. We may > need GPOS rules to handle the exceptions that vary from style to style. Gotta check this. It's beyond my knowledge. Regards, -- Theppitak Karoonboonyanan http://linux.thai.net/~thep/
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