bug#11860: 24.1; Arabic - Harakat (diacritics, short vowels) don't appear

[Kenichi Handa]

In article <83k3w0wivf.fsf@gnu.org>, Eli Zaretskii <eliz@gnu.org> writes:

> AFAICS, all Ffont_shape_gstring does is modify the FROM and TO
> components of the glyph-string.  For this to have any effect on the
> screen, these components need to be used by the drawing routines.  But
> the code in xterm.c and w32term.c that draws the composite characters
> (x_draw_composite_glyph_string_foreground) doesn't seem to use these
> components.  At least for w32term.c, we just draw the glyphs returned
> by the shaper, one by one.

Each grapheme cluster is a "display element" in the sense of
get_next_display_element.  get_next_display_element calls
next_element_from_composition which calls
composition_update_it which updates it->cmp_it.from and
it->cmp_it.to from FROM and TO elements for LGLYPH.

---
Kenichi Handa
handa@gnu.org