require'luametalatex-font-resolve' -- Ensure that font.fonts exists local keymap = {} -- There are multiple criteria for sharing backend fonts: -- * Obviously encodingbytes have to be the same. -- * The filename better is the same too. -- * Similarly the index must be the same. -- * Specifically in the PK font case *without* fixed DPI, -- The size must be the same too. -- * For fontmap based fonts, compare the name field instead, -- of the normal filename, especially to capture encoding differences. -- An alternative might be to only take the encoding into account. -- This is also required for other fonts which might not be backed by -- traditional files local function build_sharekey(fontdir) local encodingbytes = assert(fontdir.encodingbytes) local key = string.format("%i:%s:", fontdir.encodingbytes, fontdir.format) if encodingbytes == 1 then if fontdir.format == "type3" then return string.format("%s%i:%s", key, fontdir.size, fontdir.name) end key = string.format("%s%s:", key, fontdir.encoding or '') end key = string.format("%s%i:%s", key, fontdir.subfont or 1, fontdir.filename) return key end local fonts = font.fonts local fontmap = setmetatable({}, { __index = function(t, fid) local key = build_sharekey(assert(fonts[fid])) local mapped = keymap[key] local share_parent = mapped and t[mapped] or fid t[fid] = share_parent return share_parent end, }) function pdf.getfontname(fid) return fontmap[fid] end return fontmap