+-------------------- IVS
+local font_ivs_table = {} -- key: fontnumber
+local enable_ivs
+do
+ local is_ivs_enabled = false
+ local ivs -- temp table
+ local sort = table.sort
+ local uniq_flag
+ local function add_ivs_table(tg, unitable, glyphmax)
+ for i = 0, glyphmax-1 do
+ if tg[i] then
+ local gv = tg[i]
+ if gv.altuni then
+ for _,at in pairs(gv.altuni) do
+ local bu, vsel = at.unicode, at.variant
+ if vsel then
+ if vsel>=0xE0100 then vsel = vsel - 0xE0100 end
+ if not ivs[bu] then ivs[bu] = {} end
+ uniq_flag = true
+ for i,_ in pairs(ivs[bu]) do
+ if i==vs then uniq_flag = false; break end
+ end
+ if uniq_flag then
+ ivs[bu][vsel] = unitable[gv.name]
+ end
+ end
+ end
+ end
+ end
+ end
+ end
+ local function make_ivs_table(id, fname)
+ ivs = {}
+ local fl = fontloader.open(fname)
+ local unicodes = id.resources.unicodes
+ if fl.glyphs then
+ add_ivs_table(fl.glyphs, id.resources.unicodes, fl.glyphmax)
+ end
+ if fl.subfonts then
+ for _,v in pairs(fl.subfonts) do
+ add_ivs_table(v.glyphs, id.resources.unicodes, v.glyphmax)
+ end
+ end
+ fontloader.close(fl)
+ return ivs
+ end
+
+-- loading and saving
+ local font_ivs_basename = {} -- key: basename
+ local cache_ver = 4
+ local checksum = file.checksum
+
+ local function prepare_ivs_data(n, id)
+ -- test if already loaded
+ if type(id)=='number' then -- sometimes id is an integer
+ font_ivs_table[n] = font_ivs_table[id]; return
+ elseif not id then return
+ end
+ local fname = id.filename
+ local bname = file.basename(fname)
+ if not fname then
+ font_ivs_table[n] = {}; return
+ elseif font_ivs_basename[bname] then
+ font_ivs_table[n] = font_ivs_basename[bname]; return
+ end
+
+ -- if the cache is present, read it
+ local newsum = checksum(fname) -- MD5 checksum of the fontfile
+ local v = "ivs_" .. string.lower(file.nameonly(fname))
+ local dat = ltjb.load_cache(v,
+ function (t) return (t.version~=cache_ver) or (t.chksum~=newsum) end
+ )
+ -- if the cache is not found or outdated, save the cache
+ if dat then
+ font_ivs_basename[bname] = dat[1] or {}
+ else
+ dat = make_ivs_table(id, fname)
+ font_ivs_basename[bname] = dat or {}
+ ltjb.save_cache( v,
+ {
+ chksum = checksum(fname),
+ version = cache_ver,
+ dat,
+ })
+ end
+ font_ivs_table[n] = font_ivs_basename[bname]
+ end
+
+-- 組版時
+ local function ivs_jglyph(char, bp, pf, uid)
+ local p = node_new(id_whatsit,sid_user)
+ setfield(p, 'user_id', uid)
+ setfield(p, 'type', 100)
+ setfield(p, 'value', char)
+ set_attr(p, attr_curjfnt, pf)
+ set_attr(p, attr_yablshift, has_attr(bp, attr_ykblshift) or 0)
+ return p
+ end
+
+ local function do_ivs_repr(head)
+ head = to_direct(head)
+ local p, r = head
+ while p do
+ local pid = getid(p)
+ if pid==id_glyph then
+ local pf = getfont(p)
+ local q = node_next(p) -- the next node of p
+ if q and getid(q)==id_glyph then
+ local qc = getchar(q)
+ if (qc>=0xFE00 and qc<=0xFE0F) or (qc>=0xE0100 and qc<0xE01F0) then
+ -- q is a variation selector
+ if qc>=0xE0100 then qc = qc - 0xE0100 end
+ local pt = font_ivs_table[pf]
+ pt = pt and pt[getchar(p)]; pt = pt and pt[qc]
+ head, r = node_remove(head,q)
+ node_free(q)
+ if pt then
+ local np = ivs_jglyph(pt, p, pf,
+ (has_attr(p,attr_curjfnt) or 0)==pf and OTF or VSR)
+ head = node_insert_after(head, p, np)
+ head = node_remove(head,p)
+ node_free(p)
+ end
+ p = r
+ else
+ p = q
+ end
+ else
+ p = node_next(p)
+ end
+ else
+ p = node_next(p)
+ end
+ end
+ return to_node(head)
+ end
+
+ enable_ivs = function ()
+ if is_ivs_enabled then
+ ltjb.package_warning('luatexja-otf',
+ 'luatexja.otf.enable_ivs() was already called, so this call is ignored', '')
+ else
+ luatexbase.add_to_callback('hpack_filter',
+ do_ivs_repr,'do_ivs', 1)
+ luatexbase.add_to_callback('pre_linebreak_filter',
+ do_ivs_repr, 'do_ivs', 1)
+ local ivs_callback = function (name, size, id)
+ return font_callback(
+ name, size, id,
+ function (name, size, id) return luatexja.font_callback(name, size, id) end
+ )
+ end
+ luatexbase.add_to_callback('luatexja.define_font',
+ function (res, name, size, id)
+ prepare_ivs_data(id, res)
+ end,
+ 'prepare_ivs_data', 1)
+ for i=1,font.nextid()-1 do
+ if identifiers[i] then prepare_ivs_data(i, identifiers[i]) end
+ end
+ is_ivs_enabled = true
+ end
+ end
+end
+