Thai Shapper without needed extra glyphs for vowel/tonemark at different heights

[Chookij Vanatham <chookij vanatham eng sun com>]

Hi Robert,


]From: Robert Brady <robert suse co uk>
]Subject: Re: Industry Thai Cell-Clustering Rules
] 
] They can also do y adjustments on glyphs.  It would be quite easy I guess
] to make a Thai renderer that could do nicely positioned vowels without
] needed extra glyphs for vowel-at-different-heights.
] 

I just understand what you were talking about this because of
the data structure of PangoGlyphGeometry.


struct PangoGlyphGeometry
 {
   PangoGlyphUnit width;
   PangoGlyphUnit x_offset;  
   PangoGlyphUnit y_offset;
 };
 
Then, may be, we don't need to have various kinds of Thai WIN/MAC font layout
but the font might still need to have the special glyphs for U+0E0D and U+0E10.
Those special glyphs won't have the bottom piece which is below the main body
of these two consonances. Then, it should be ok. Right ?

Should we try that ?

Chookij V.