vega/text/test-layout.c, branch masterSurface runtime projecting Pure views across pixel, terminal, CLI, and web.
http://git.yeowoo.org/vega/atom?h=master2026-09-28T14:52:13ZSet text in a stack of fonts: each grapheme cluster in the first that has it2026-09-28T14:52:13Zeunhhunecpition205@gmail.com2026-09-28T14:52:13Zurn:sha1:a4ca275ad1b5edc15474407e2852f8fe9abaac4e
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.
Set paragraphs into lines: bidi, script runs, shaping, line breaking, visual order2026-09-28T12:03:50Zeunhhunecpition205@gmail.com2026-09-28T12:03:50Zurn:sha1:202e6bf4677565c0cfbef5340119d0f9674bf17d
text/layout.c puts the checked parts together: a paragraph's levels,
scripts resolved for Common and Inherited characters, break
opportunities, one shaping to measure, lines broken at the last
opportunity that fits (trailing spaces hang, and a line that shapes
wider than measured backs off), then per line L1, runs of one level and
one script shaped again, the runs in L2's order and their glyphs placed.
test-layout checks 30,000 random mixed-script paragraphs: lines cover
the text, mandatory breaks end lines, lines fit when they can, and
glyphs come in the order UAX #9 gives the characters. vega-symbols
paragraph draws a layout through the symbol file's glyphs.