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 node_insert_before = node.insert_before
  12 local node_insert_after = node.insert_after
  13 local node_hpack = node.hpack
  14 local round = tex.round
  15
  16 local id_penalty = node.id('penalty')
  17 local id_glyph = node.id('glyph')
  18 local id_glue = node.id('glue')
  19 local id_glue_spec = node.id('glue_spec')
  20 local id_kern = node.id('kern')
  21 local id_hlist = node.id('hlist')
  22 local id_ins = node.id('ins')
  23 local id_mark = node.id('mark')
  24 local id_adjust = node.id('adjust')
  25 local id_math = node.id('math')
  26 local id_whatsit = node.id('whatsit')
  27
  28 local attr_icflag = luatexbase.attributes['ltj@icflag']
  29 local attr_autospc = luatexbase.attributes['ltj@autospc']
  30 local attr_autoxspc = luatexbase.attributes['ltj@autoxspc']
  31 local attr_curjfnt = luatexbase.attributes['ltj@curjfnt']
  32 local max_dimen = 1073741823
  33
  34 local ITALIC = 1
  35 local TEMPORARY = 2
  36 local FROM_JFM = 3
  37 local KINSOKU = 4
  38 local LINE_END = 5
  39
  40 local kanji_skip
  41 local xkanji_skip
  42
  43 -- (glyph_node nr) ... (node nq) <GLUE> ,,, (node np)
  44 local np, nq, nrc
  45 local no_skip = 0
  46 local after_schar = 1
  47 local after_wchar = 2 -- nr is a Japanese glyph_node
  48 local insert_skip = no_skip
  49 local head
  50
  51 local cstb_get_inhibit_xsp_table = ltj.int_get_inhibit_xsp_table
  52
  53 local function is_japanese_glyph_node(p)
  54    return p and (p.id==id_glyph)
  55    and (p.font==has_attr(p,attr_curjfnt))
  56 end
  57
  58 local function get_zero_glue()
  59    local g = node_new(id_glue_spec)
  60    g.width = 0; g.stretch_order = 0; g.stretch = 0
  61    g.shrink_order = 0; g.shrink = 0
  62    return g
  63 end
  64
  65 -- the following 2 functions are the lowest part.
  66 -- cx: the Kanji code of np
  67 local function insert_ascii_kanji_xkskip(q, cx)
  68    if cstb_get_inhibit_xsp_table(cx)<=1 then return end
  69    local g = node_new(id_glue)
  70    g.subtype = 0; g.spec = node.copy(xkanji_skip)
  71    node_insert_after(head, q, g)
  72 end
  73
  74 local function insert_kanji_ascii_xkskip(q, p)
  75    local g=true
  76    local c = p.char
  77    while p.components and p.subtype
  78       and math.floor(p.subtype/2)%2==1 do
  79       p = p.components; c = p.char
  80    end
  81    if cstb_get_inhibit_xsp_table(c)%2 == 1 then
  82       if cstb_get_inhibit_xsp_table(nrc)%2 == 0 then g = false end
  83    else g = false
  84    end
  85    if g then
  86       g = node_new(id_glue)
  87       g.subtype = 0; g.spec = node.copy(xkanji_skip)
  88       node_insert_after(head, q, g)
  89    end
  90 end
  91
  92
  93 local function set_insert_skip_after_achar(p)
  94    local c = p.char
  95    while p.components and p.subtype
  96       and math.floor(p.subtype/2)%2 == 1 do
  97       p=node.tail(p.components); c = p.char
  98    end
  99   if cstb_get_inhibit_xsp_table(c)>=2 then
 100      insert_skip = after_schar
 101   else
 102      insert_skip = no_skip
 103   end
 104 end
 105
 106 local function get_kanji_skip_from_jfm(p)
 107    local px = { ltj.font_metric_table[p.font].size,
 108                 ltj.font_metric_table[p.font].jfm }
 109    local i = ltj.metrics[px[2]].kanjiskip
 110    print(p.font, px[1], px[2], ltj.metrics[px[2]].dir, i)
 111    if i then
 112       return { round(i[1]*px[1]), round(i[2]*px[1]), round(i[3]*px[1]) }
 113    else return nil
 114    end
 115 end
 116
 117 local function insert_kanji_skip()
 118    print('a', utf.char(np.char))
 119    local g = node_new(id_glue); g.subtype=0
 120    if kanji_skip.width==max_dimen then -- use kanjiskip from JFM
 121       local gx = node_new(id_glue_spec);
 122       gx.stretch_order = 0; gx.shrink_order = 0
 123       local bk = nil -- incomplete
 124       local ak = get_kanji_skip_from_jfm(np)
 125       if bk then
 126          if ak then
 127             gx.width = round(ltj.ja_diffmet_rule(bk[1], ak[1]))
 128             gx.stretch = round(ltj.ja_diffmet_rule(bk[2], ak[2]))
 129             gx.shrink = -round(ltj.ja_diffmet_rule(-bk[3], -ak[3]))
 130          else
 131             gx.width = bk[1]; gx.stretch = bk[2]; gx.shrink = bk[3]
 132          end
 133       elseif ak then
 134          gx.width = ak[1]; gx.stretch = ak[2]; gx.shrink = ak[3]
 135       else
 136          gx = get_zero_glue()-- ???
 137       end
 138       g.spec = gx
 139    else
 140       g.spec=node.copy(kanji_skip)
 141    end
 142    local h = node_prev(np)
 143    if h  and has_attr(h, attr_icflag)==TEMPORARY then
 144       if h.id==id_kern then
 145          g.spec.width = g.spec.width + h.kern
 146          head = node.remove(head, h)
 147          node_insert_before(head, np, g)
 148       else
 149          h.spec.width = g.spec.width + h.spec.width
 150          h.spec.stretch = g.spec.stretch + h.spec.stretch
 151          h.spec.shrink = g.spec.shrink + h.spec.shrink
 152       end
 153    else
 154       node_insert_before(head, np, g)
 155    end
 156    print('b', utf.char(np.char))
 157 end
 158
 159 -- When p is a glyph_node ...
 160 local function insks_around_char()
 161    if is_japanese_glyph_node(np) then
 162       if insert_skip==after_wchar then
 163          insert_kanji_skip()
 164       elseif insert_skip==after_schar then
 165          insert_ascii_kanji_xkskip(nq, np.char)
 166       end
 167       insert_skip=after_wchar; nrc = np.char
 168    else
 169       if insert_skip==after_wchar then
 170          insert_kanji_ascii_xkskip(nq, np)
 171       end
 172       set_insert_skip_after_achar(np)
 173    end
 174    nq = np
 175 end
 176
 177 -- Return first and last glyph nodes in a hbox
 178 local first_char = nil
 179 local last_char = nil
 180 local find_first_char = nil
 181 local function check_box(box_ptr)
 182    local p = box_ptr; local found_visible_node = false
 183    while p do
 184       if p.id==id_glyph then
 185          repeat
 186             if find_first_char then
 187                first_char = p; find_first_char = false
 188             end
 189             last_char = p; found_visible_node = true; p=node_next(p)
 190             if not p then return found_visible_node end
 191          until p.id~=id_glyph
 192       end
 193       if p.id==id_hlist then
 194          found_visible_node = true
 195          if p.shift==0 then
 196             if check_box(p.head) then found_visible_node = true end
 197          else if find_first_char then
 198                find_first_char = false
 199             else
 200                last_char = nil
 201             end
 202          end
 203       elseif p.id==id_ins    or p.id==id_mark
 204           or p.id==id_adjust or p.id==id_whatsit
 205           or p.id==id_penalty then
 206          p=p
 207       else
 208          found_visible_node = true
 209          if find_first_char then
 210             find_first_char = false
 211          else
 212             last_char = nil
 213          end
 214       end
 215       p = node_next(p)
 216    end
 217    return found_visible_node
 218 end
 219
 220 -- When np is a hlist_node ...
 221 local function insks_around_hbox()
 222    if np.shift==0 then
 223       find_first_char = true; first_char = nil; last_char = nil
 224       if check_box(np.head) then
 225          -- first char
 226          if is_japanese_glyph_node(first_char) then
 227             nrc = first_char.char
 228             if insert_skip==after_schar then
 229                insert_ascii_kanji_xkskip(nq, first_char.char)
 230             elseif insert_skip==after_wchar then
 231                insert_kanji_skip()
 232             end
 233             insert_skip = after_wchar
 234          elseif first_char then
 235             if insert_skip==after_wchar then
 236                insert_kanji_ascii_xkskip(nq, first_char)
 237             end
 238             set_insert_skip_after_achar(first_char)
 239          end
 240          -- last char
 241          if is_japanese_glyph_node(last_char) then
 242             if is_japanese_glyph_node(node_next(np)) then
 243                local g = node_new(id_glue)
 244                g.subtype = 0; g.spec = node.copy(kanji_skip)
 245                node_insert_after(head, np, g)
 246             end
 247             insert_skip = after_wchar; nrc = last_char.char
 248          elseif last_char then
 249             set_insert_skip_after_achar(last_char)
 250          else insert_skip = no_skip
 251          end
 252       else insert_skip = no_skip
 253       end
 254    else insert_skip = no_skip
 255    end
 256    nq = np
 257 end
 258
 259 -- When np is a penalty ...
 260 local function insks_around_penalty()
 261    nq = np
 262 end
 263
 264 -- When np is a kern ...
 265 --
 266 local function insks_around_kern()
 267    if np.subtype==1 then -- \kern or \/
 268       local i = has_attr(np, attr_icflag)
 269       if not i or i==FROM_JFM then -- \kern
 270          insert_skip = no_skip
 271       elseif i==ITALIC or i==LINE_END or i==TEMPORARY then
 272          nq = np
 273       end
 274    elseif np.subtype==2 then
 275       -- (np = kern from \accent) .. (accent char) .. (kern from \accent) .. (glyph)
 276       np = node_next(node_next(np))
 277    end
 278 end
 279
 280 -- When np is a math_node ...
 281 local function insks_around_math()
 282    local g = { char = -1 }
 283    if (np.subtype==0) and (insert_skip==after_wchar) then
 284       insert_kanji_ascii_xkskip(nq, g)
 285       insert_skip = no_skip
 286    else
 287       nq = np; set_insert_skip_after_achar(g)
 288    end
 289 end
 290
 291 function ltj.int_insert_kanji_skip(ahead)
 292    kanji_skip=tex.skip['kanjiskip']
 293    xkanji_skip=tex.skip['xkanjiskip']
 294    head = ahead
 295    np = head; nq = nil; insert_skip = no_skip
 296    while np do
 297       if np.id==id_glyph then
 298          repeat
 299             insks_around_char(); np=node_next(np)
 300          until (not np) or np.id~=id_glyph
 301       else
 302          if np.id==id_hlist then
 303             insks_around_hbox()
 304          elseif np.id==id_penalty then
 305             insks_around_penalty()
 306          elseif np.id==id_kern then
 307             insks_around_kern()
 308          elseif np.id==id_math then
 309             insks_around_math()
 310          elseif np.id==id_ins    or np.id==id_mark
 311              or np.id==id_adjust or np.id==id_whatsit then
 312             -- do nothing
 313             np = np
 314          else
 315             -- rule, disc, glue, margin_kern
 316             insert_skip = no_skip
 317          end
 318          np = node_next(np)
 319       end
 320    end
 321    return head
 322 end