API additions:
hb_segment_properties_t
HB_SEGMENT_PROPERTIES_DEFAULT
hb_segment_properties_equal()
hb_segment_properties_hash()
hb_buffer_set_segment_properties()
hb_buffer_get_segment_properties()
hb_ot_layout_glyph_class_t
hb_shape_plan_t
hb_shape_plan_create()
hb_shape_plan_create_cached()
hb_shape_plan_get_empty()
hb_shape_plan_reference()
hb_shape_plan_destroy()
hb_shape_plan_set_user_data()
hb_shape_plan_get_user_data()
hb_shape_plan_execute()
hb_ot_shape_plan_collect_lookups()
API changes:
Rename hb_ot_layout_feature_get_lookup_indexes() to
hb_ot_layout_feature_get_lookups().
New header file:
hb-shape-plan.h
And a bunch of prototyped but not implemented stuff. Coming soon.
(Tests fail because of the prototypes right now.)
We need the font for glyph lookup during GSUB pauses in Indic shaper.
Could perhaps be avoided, but at this point, we don't mean to support
separate substitute()/position() entry points (anymore), so there is
no point in not providing the font to GSUB.
Gives me a good 10% speedup for the Devanagari test case. Less so
for less lookup-intensive tests.
For the Devanagari test case, the false positive rate of the GSUB digest
is 4%.
This commit: a3313e5400 broke MarkMarkPos
when one of the marks itself is a ligature. That regressed 26 Tibetan
tests (up from zero!). Fix that. Tibetan back to zero.
This was broken as a result of 7b84c536c1.
As Khaled reported, MarkMark positioning was broken with glyphs
resulting from a MultipleSubst. Fixed. Test with the ALLAH character
in Amiri.
I was reconsidering whether y should grow down, since all three/four
times I've used this API I was tricked and got that wrong in my use.
So I was very inclined to make y grow down instead of up. However,
considering that the font space has y up and it would be very confusing
for callbacks to work against that, I decided that what I really want
is for the user to be able to set y_scale to a negative number to imply
that user-space y grows down.
Changing x_scale/y_scale from unsigned int to int allows that, and I've
made pango to use that instead of negating glyph y_offset later. hb-ft
however still has y group up. I *guess* that's how FreeType works?
I'm not sure, FreeType docs don't make this clear...
I'm happy with the resolution :-).