src/luatexja-xkanji.lua

   1 ------------------------------------------------------------------------
   2 -- MAIN PROCESS STEP 3: insert \xkanjiskip (prefix: none)
   3 ------------------------------------------------------------------------
   4
   5 local node_type = node.type
   6 local node_new = node.new
   7 local node_prev = node.prev
   8 local node_next = node.next
   9 local node_copy = node.copy
  10 local has_attr = node.has_attribute
  11 local set_attr = node.set_attribute
  12 local node_insert_before = node.insert_before
  13 local node_insert_after = node.insert_after
  14 local node_hpack = node.hpack
  15 local round = tex.round
  16
  17 local id_penalty = node.id('penalty')
  18 local id_glyph = node.id('glyph')
  19 local id_glue = node.id('glue')
  20 local id_glue_spec = node.id('glue_spec')
  21 local id_kern = node.id('kern')
  22 local id_hlist = node.id('hlist')
  23 local id_ins = node.id('ins')
  24 local id_mark = node.id('mark')
  25 local id_adjust = node.id('adjust')
  26 local id_math = node.id('math')
  27 local id_whatsit = node.id('whatsit')
  28
  29 local attr_icflag = luatexbase.attributes['ltj@icflag']
  30 local attr_autospc = luatexbase.attributes['ltj@autospc']
  31 local attr_autoxspc = luatexbase.attributes['ltj@autoxspc']
  32 local attr_curjfnt = luatexbase.attributes['ltj@curjfnt']
  33 local max_dimen = 1073741823
  34
  35 local ITALIC = 1
  36 local TEMPORARY = 2
  37 local FROM_JFM = 3
  38 local KINSOKU = 4
  39 local LINE_END = 5
  40 local KANJI_SKIP = 6
  41 local XKANJI_SKIP = 7
  42 local PACKED = 8
  43
  44 local kanji_skip
  45 local xkanji_skip
  46
  47 -- (glyph_node nr) ... (node nq) <GLUE> ,,, (node np)
  48 local np, nq, nrc, nrf
  49 local np_spc, nr_spc
  50 local no_skip = 0
  51 local after_schar = 1
  52 local after_wchar = 2 -- nr is a Japanese glyph_node
  53 local insert_skip = no_skip
  54 local head
  55
  56 local cstb_get_penalty_table = ltj.int_get_penalty_table
  57 local cstb_get_skip_table = ltj.int_get_skip_table
  58
  59 local function is_japanese_glyph_node(p)
  60    return p and (p.id==id_glyph)
  61    and (p.font==has_attr(p,attr_curjfnt))
  62 end
  63
  64 local function get_zero_glue()
  65    local g = node_new(id_glue_spec)
  66    g.width = 0; g.stretch_order = 0; g.stretch = 0
  67    g.shrink_order = 0; g.shrink = 0
  68    return g
  69 end
  70
  71 local function skip_table_to_spec(n)
  72    local g = node_new(id_glue_spec)
  73    local st = cstb_get_skip_table(n, ltj.box_stack_level)
  74    g.width = st.width; g.stretch = st.stretch; g.shrink = st.shrink
  75    g.stretch_order = st.stretch_order; g.shrink_order = st.shrink_order
  76    return g
  77 end
  78
  79 local function add_glue_spec(g,h)
  80    -- g := g + h
  81    g.width = g.width + h.width
  82    if g.stretch_order<h.stretch_order then
  83       g.stretch_order = h.stretch_order
  84       g.stretch = h.stretch
  85    elseif g.stretch_order==h.stretch_order then
  86       g.stretch = g.stretch + h.stretch
  87    end
  88    if g.shrink_order<h.shrink_order then
  89       g.shrink_order = h.shrink_order
  90       g.shrink = h.shrink
  91    elseif g.shrink_order==h.shrink_order then
  92       g.shrink = g.shrink + h.shrink
  93    end
  94 end
  95
  96 -- lowest part of \xkanjiskip
  97 local function get_xkanji_skip_from_jfm(pf)
  98    if pf then
  99       local px = { ltj.font_metric_table[pf].size,
 100                    ltj.font_metric_table[pf].jfm }
 101       local i = ltj.metrics[px[2]].xkanjiskip
 102       if i then
 103          return { round(i[1]*px[1]), round(i[2]*px[1]), round(i[3]*px[1]) }
 104       else return nil
 105       end
 106    else return nil
 107    end
 108 end
 109
 110 local function insert_xkanjiskip_node(q, f, p)
 111    if nr_spc[2] or np_spc[2] then
 112       local g = node_new(id_glue); g.subtype = 0
 113       if xkanji_skip.width==max_dimen then -- use xkanjiskip from JFM
 114          local gx = node_new(id_glue_spec)
 115          gx.stretch_order = 0; gx.shrink_order = 0
 116          local ak = get_xkanji_skip_from_jfm(f)
 117          if ak then
 118             gx.width = ak[1]; gx.stretch = ak[2]; gx.shrink = ak[3]
 119          else gx = get_zero_glue() -- fallback
 120          end
 121          g.spec = gx
 122       else g.spec=node_copy(xkanji_skip)
 123       end
 124       local h = node_prev(p)
 125       if h  and has_attr(h, attr_icflag)==TEMPORARY then
 126          if h.id==id_kern then
 127             g.spec.width = g.spec.width + h.kern
 128             set_attr(g,attr_icflag,XKANJI_SKIP)
 129             node_insert_after(head, q, g)
 130             head = node.remove(head, h)
 131          else
 132             add_glue_spec(h.spec, g.spec)
 133          end
 134       else
 135          set_attr(g,attr_icflag,XKANJI_SKIP)
 136          node_insert_after(head, q, g)
 137       end
 138    end
 139 end
 140
 141 local function insert_ascii_kanji_xkskip(q, p)
 142    if cstb_get_penalty_table('xsp', p.char, 3, ltj.box_stack_level)<=1 then return end
 143    insert_xkanjiskip_node(q, p.font, p)
 144 end
 145
 146 local function insert_kanji_ascii_xkskip(q, p)
 147    local g = true
 148    local c = p.char
 149    while p.components and p.subtype
 150       and math.floor(p.subtype/2)%2==1 do
 151       p = p.components; c = p.char
 152    end
 153    if cstb_get_penalty_table('xsp', c, 3, ltj.box_stack_level)%2 == 1 then
 154       if cstb_get_penalty_table('xsp', nrc, 3, ltj.box_stack_level)%2 == 0 then g = false end
 155    else g = false
 156    end
 157    if g then insert_xkanjiskip_node(q, nrf, p) end
 158 end
 159
 160 local function set_insert_skip_after_achar(p)
 161    local c = p.char
 162    while p.components and p.subtype
 163       and math.floor(p.subtype/2)%2 == 1 do
 164       p=node.tail(p.components); c = p.char
 165    end
 166   if cstb_get_penalty_table('xsp', c, 3, ltj.box_stack_level)>=2 then
 167      insert_skip = after_schar
 168   else
 169      insert_skip = no_skip
 170   end
 171 end
 172
 173 -- lowest part of \kanjiskip
 174 local function get_kanji_skip_from_jfm(pf)
 175    if pf then
 176       local px = { ltj.font_metric_table[pf].size,
 177                    ltj.font_metric_table[pf].jfm }
 178       local i = ltj.metrics[px[2]].kanjiskip
 179       if i then
 180          return { round(i[1]*px[1]), round(i[2]*px[1]), round(i[3]*px[1]) }
 181       else return nil
 182       end
 183    else return nil
 184    end
 185 end
 186
 187 local function insert_kanji_skip(ope, p)
 188    local g = node_new(id_glue); g.subtype=0
 189    if nr_spc[1] or np_spc[1] then
 190       if kanji_skip.width==max_dimen then -- use kanjiskip from JFM
 191          local gx = node_new(id_glue_spec);
 192          gx.stretch_order = 0; gx.shrink_order = 0
 193          local bk = get_kanji_skip_from_jfm(nrf)
 194          local ak = get_kanji_skip_from_jfm(p.font)
 195          if bk then
 196             if ak then
 197                gx.width = round(ltj.ja_diffmet_rule(bk[1], ak[1]))
 198                gx.stretch = round(ltj.ja_diffmet_rule(bk[2], ak[2]))
 199                gx.shrink = -round(ltj.ja_diffmet_rule(-bk[3], -ak[3]))
 200             else
 201                gx.width = bk[1]; gx.stretch = bk[2]; gx.shrink = bk[3]
 202             end
 203          elseif ak then
 204             gx.width = ak[1]; gx.stretch = ak[2]; gx.shrink = ak[3]
 205          else gx = get_zero_glue() -- fallback
 206          end
 207          g.spec = gx
 208       else g.spec=node_copy(kanji_skip)
 209       end
 210    else g.spec = get_zero_glue()
 211    end
 212    local h = node_prev(p)
 213    if h  and has_attr(h, attr_icflag)==TEMPORARY then
 214       if h.id==id_kern then
 215          g.spec.width = g.spec.width + h.kern
 216          head = node.remove(head, h)
 217          set_attr(g,attr_icflag,KANJI_SKIP)
 218          ope(head, p, g)
 219       else
 220          add_glue_spec(h.spec, g.spec)
 221       end
 222    else
 223       set_attr(g,attr_icflag,KANJI_SKIP)
 224       ope(head, p, g)
 225    end
 226 end
 227
 228 -- When p is a glyph_node ...
 229 local function insks_around_char()
 230    if is_japanese_glyph_node(np) then
 231       if insert_skip==after_wchar then
 232          insert_kanji_skip(node_insert_before, np)
 233       elseif insert_skip==after_schar then
 234          insert_ascii_kanji_xkskip(nq, np)
 235       end
 236       insert_skip=after_wchar
 237       nrc = np.char; nrf = np.font; nr_spc = np_spc
 238    else
 239       if insert_skip==after_wchar then
 240          insert_kanji_ascii_xkskip(nq, np)
 241       end
 242       set_insert_skip_after_achar(np); nr_spc = np_spc
 243    end
 244    nq = np
 245 end
 246
 247 -- Return first and last glyph nodes in a hbox
 248 local first_char = nil
 249 local last_char = nil
 250 local find_first_char = nil
 251 local function check_box(box_ptr)
 252    local p = box_ptr; local found_visible_node = false
 253    if not p then
 254       find_first_char = false; first_char = nil; last_char = nil
 255       return true
 256    end
 257    while p do
 258       if p.id==id_glyph then
 259          repeat
 260             if find_first_char then
 261                first_char = p; find_first_char = false
 262             end
 263             last_char = p; found_visible_node = true; p=node_next(p)
 264             if not p then return found_visible_node end
 265          until p.id~=id_glyph
 266       end
 267       if p.id==id_hlist then
 268          if has_attr(p, attr_icflag)==PACKED then
 269             for q in node.traverse_id(id_glyph, p.head) do
 270                if find_first_char then
 271                   first_char = q; find_first_char = false
 272                end
 273                last_char = q; found_visible_node = true
 274             end
 275          else
 276             if p.shift==0 then
 277                if check_box(p.head) then found_visible_node = true end
 278             else if find_first_char then
 279                   find_first_char = false
 280                else
 281                   last_char = nil
 282                end
 283             end
 284          end
 285       elseif p.id==id_ins    or p.id==id_mark
 286           or p.id==id_adjust or p.id==id_whatsit
 287           or p.id==id_penalty then
 288          p=p
 289       else
 290          found_visible_node = true
 291          if find_first_char then
 292             find_first_char = false
 293          else
 294             last_char = nil
 295          end
 296       end
 297       p = node_next(p)
 298    end
 299    return found_visible_node
 300 end
 301
 302 -- When np is a hlist_node ...
 303 local function insks_around_hbox()
 304    if np.shift==0 then
 305       find_first_char = true; first_char = nil; last_char = nil
 306       if check_box(np.head) then
 307          -- first char
 308          if is_japanese_glyph_node(first_char) then
 309             nrc = first_char.char; nrf = first_char.font
 310             if insert_skip==after_schar then
 311                insert_ascii_kanji_xkskip(nq, first_char)
 312             elseif insert_skip==after_wchar then
 313                np_spc = { has_attr(first_char, attr_autospc)==1,
 314                           has_attr(first_char, attr_autoxspc)==1 }
 315                insert_kanji_skip(node_insert_before, np)
 316             end
 317             insert_skip = after_wchar
 318          elseif first_char then
 319             if insert_skip==after_wchar then
 320                insert_kanji_ascii_xkskip(nq, first_char)
 321             end
 322             set_insert_skip_after_achar(first_char)
 323          end
 324          -- last char
 325          if is_japanese_glyph_node(last_char) then
 326             insert_skip = after_wchar
 327             nrc = last_char.char; nrf = last_char.font
 328             nr_spc = { has_attr(last_char, attr_autospc)==1,
 329                        has_attr(last_char, attr_autoxspc)==1 }
 330             if is_japanese_glyph_node(node_next(np)) then
 331                insert_kanji_skip(node_insert_after, np)
 332             end
 333          elseif last_char then
 334             set_insert_skip_after_achar(last_char)
 335             nr_spc = { has_attr(last_char, attr_autospc)==1,
 336                        has_attr(last_char, attr_autoxspc)==1 }
 337          else insert_skip = no_skip
 338          end
 339       else insert_skip = no_skip
 340       end
 341    else insert_skip = no_skip
 342    end
 343    nq = np
 344 end
 345
 346 -- When np is a penalty ...
 347 local function insks_around_penalty()
 348    nq = np
 349 end
 350
 351 -- When np is a kern ...
 352 --
 353 local function insks_around_kern()
 354    if np.subtype==1 then -- \kern or \/
 355       local i = has_attr(np, attr_icflag)
 356       if not i or i==FROM_JFM then -- \kern
 357          insert_skip = no_skip
 358       elseif i==ITALIC or i==LINE_END or i==TEMPORARY then
 359          nq = np
 360       end
 361    elseif np.subtype==2 then
 362       -- (np = kern from \accent) .. (accent char) .. (kern from \accent) .. (glyph)
 363       np = node_next(node_next(np))
 364    else  -- kern from TFM
 365       nq = np
 366    end
 367 end
 368
 369 -- When np is a math_node ...
 370 local function insks_around_math()
 371    local g = { char = -1 }
 372    if (np.subtype==0) and (insert_skip==after_wchar) then
 373       insert_kanji_ascii_xkskip(nq, g)
 374       insert_skip = no_skip
 375    else
 376       nq = np; set_insert_skip_after_achar(g); nr_spc = np_spc
 377    end
 378 end
 379
 380 function ltj.int_insert_kanji_skip(ahead)
 381    kanji_skip=skip_table_to_spec('kanjiskip')
 382    xkanji_skip=skip_table_to_spec('xkanjiskip')
 383    head = ahead
 384    np = head; nq = nil; insert_skip = no_skip
 385    while np do
 386       np_spc = { (has_attr(np, attr_autospc)==1),
 387                  (has_attr(np, attr_autoxspc)==1) }
 388       if np.id==id_glyph then
 389          repeat
 390             np_spc = { has_attr(np, attr_autospc)==1,
 391                        has_attr(np, attr_autoxspc)==1 }
 392             insks_around_char(); np=node_next(np)
 393          until (not np) or np.id~=id_glyph
 394       else
 395          if np.id==id_hlist then
 396             insks_around_hbox()
 397          elseif np.id==id_penalty then
 398             insks_around_penalty()
 399          elseif np.id==id_kern then
 400             insks_around_kern()
 401          elseif np.id==id_math then
 402             insks_around_math()
 403          elseif np.id==id_ins    or np.id==id_mark
 404              or np.id==id_adjust or np.id==id_whatsit then
 405             -- do nothing
 406             np = np
 407          else
 408             -- rule, disc, glue, margin_kern
 409             insert_skip = no_skip
 410          end
 411          np = node_next(np)
 412       end
 413    end
 414    return head
 415 end