pub fn undrawn(atlas: &FontAtlasDef, lang: &Lang) -> Vec<ContentError>Expand description
Every character of lang’s text (Lang::texts) that atlas can’t
draw in its language: a check across assets, after both load. A
language’s wide characters (as its widths have them, Lang::widths:
a pack’s or the source’s) must be in the wide set it names, or in any
set if it names none; the rest narrow. A pack that names a set the atlas
lacks is one error, on its lang.ron (the source, on its folder), and
its wide characters aren’t checked. One error per language and
character, in the order of their first use, on the file of that use
(TextAt::path), naming its key and how many more keys of that
language use it. Control characters (a \n) are never errors; a
combining mark (is_combining_mark) always is, glyph or not. The
errors have no line: a Lang keeps keys, which find the line.