Set text in a stack of fonts: each grapheme cluster in the first that has it

vega_layout takes fonts in order of preference (VegaFonts). A grapheme
cluster goes to the first font that has all its characters (default
ignorables aside: shaping hides them); a cluster of Common and Inherited
characters stays in the font before it when that one has it, so the spaces
between Arabic words stay in the Arabic font; failing that, the first font
with its first character, else the first font. Runs split where the font
changes too. Positions are in the first font's units, a run's pen scaled
as a whole so rounding does not add up. Callers can narrow what a font
has (a symbol file holds only the glyphs its codes reach).

vega_default_ignorable is shape.c's HarfBuzz 10.2 set, now public.

1 files changed, 2 insertions, 1 deletions

diff --git a/text/test-layout.c b/text/test-layout.c
index 5282572..420733a 100644
--- a/text/test-layout.c
+++ b/text/test-layout.c
@@ -88,6 +88,7 @@ int main(int argc, char **argv) {
                                        '1', '2', '3', 0x0661, 0x0662, 0x200E, 0x200F, 0x2028, 0x2014, 0x00A0};
     VegaShaper *shaper = vega_shaper_new();
     VegaLayout layout = {0};
+    VegaFonts fonts = {{&shaping}, 1, NULL, NULL};
     size_t lines = 0, glyphs = 0, characters = 0;
     double seconds = 0;
     static uint32_t codes[2048];
@@ -115,7 +116,7 @@ int main(int argc, char **argv) {
         int32_t width = below(5) == 0 ? 0 : (int32_t)(shaping.upem * (1 + below(30)));
         struct timespec a, b;
         clock_gettime(CLOCK_MONOTONIC, &a);
-        if (!vega_layout(&layout, shaper, &shaping, codes, n, direction, width)) {
+        if (!vega_layout(&layout, shaper, &fonts, codes, n, direction, width)) {
             fail(k, "no layout");
             continue;
         }