If there is no GPOS, zero mark advances.
If there *is* GPOS and the shaper requests so, zero mark advances for
attached marks.
Fixes regression with Tibetan, where the font has GPOS, and marks a
glyph as mark where it shouldn't get zero advance.
When we removed the separate Hangul shaper, the specific normalization
preference of Hangul was lost. Fix that. Also, the Thai shaper was
copied from Hangul, so had the fully-composed normalization behavior,
which was unnecessary. So, fix that too.
Previously, we were NOT actually recomposing Hangul Jamo. We do now.
The two lines in:
test/shaping/texts/in-tree/shaper-default/script-hangul/misc/misc.txt
Now render the same with the UnDotum.ttf font. Previously the second
linle was rendering boxes.
We can also start applying OpenType Jamo features later. At this time,
I have no idea how the 'ljmo', 'vjmo', 'tjmo' features are supposed to
work. Maybe someone can explain them to me?
As requested by Jonathan Kew.
We need to devise a better mechanism to choose which scripts to
pass through the Indic shaper. Moreover, currently we are storing
data for some scripts in the Indic shaper that are not even going
through that shaper. Need to find a better way...
Nothing functional in there yet.
So far, we're parsing IndicSyllabicCategory.txt and IndicMatraCategory.txt
fils from Unicode Character Database and store them in an array to be used
by the shaper. Also hooked up the shaper, but it does not do anything
right now.
Add support for classic Mongolian script to the Arabic shaper.
Still work to be done around U+180E MONGOLIAN VOWEL SEPARATOR as it
should not be included in the final glyph stream the same way that
ZWNJ, etc should not appear in the final glyph stream.
But the joining part should be done.
There remains the question of how should the U+18A9 MONGOLIAN LETTER ALI
GALI DAGALGA be handled as it has General Category NSM but a letter
nonetheless. For now, our generic logic makes this a joining T instead
of joining D as other Mongolian letters are.