diff options
Diffstat (limited to 'tex/context/base/typo-dir.lua')
-rw-r--r-- | tex/context/base/typo-dir.lua | 926 |
1 files changed, 463 insertions, 463 deletions
diff --git a/tex/context/base/typo-dir.lua b/tex/context/base/typo-dir.lua index f02395475..7e5f8c2d3 100644 --- a/tex/context/base/typo-dir.lua +++ b/tex/context/base/typo-dir.lua @@ -1,463 +1,463 @@ -if not modules then modules = { } end modules ['typo-dir'] = {
- version = 1.001,
- comment = "companion to typo-dir.mkiv",
- author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
- copyright = "PRAGMA ADE / ConTeXt Development Team",
- license = "see context related readme files"
-}
-
--- todo: also use end_of_math here?
-
-local next, type = next, type
-local format, insert, sub, find, match = string.format, table.insert, string.sub, string.find, string.match
-local utfchar = utf.char
-
--- vertical space handler
-
-local nodes, node = nodes, node
-
-local trace_directions = false trackers.register("typesetters.directions", function(v) trace_directions = v end)
-
-local report_directions = logs.reporter("typesetting","directions")
-
-local traverse_id = node.traverse_id
-local insert_node_before = node.insert_before
-local insert_node_after = node.insert_after
-local remove_node = nodes.remove
-
-local texattribute = tex.attribute
-local unsetvalue = attributes.unsetvalue
-
-local nodecodes = nodes.nodecodes
-local whatcodes = nodes.whatcodes
-local mathcodes = nodes.mathcodes
-
-local tasks = nodes.tasks
-
-local glyph_code = nodecodes.glyph
-local whatsit_code = nodecodes.whatsit
-local math_code = nodecodes.math
-
-local localpar_code = whatcodes.localpar
-local dir_code = whatcodes.dir
-
-local nodepool = nodes.pool
-
-local new_textdir = nodepool.textdir
-
-local beginmath_code = mathcodes.beginmath
-local endmath_code = mathcodes.endmath
-
-local fonthashes = fonts.hashes
-local fontdata = fonthashes.identifiers
-local fontchar = fonthashes.characters
-
-local chardata = characters.data
-local chardirs = characters.directions -- maybe make a special mirror table
-
---~ Analysis by Idris:
---~
---~ 1. Assuming the reading- vs word-order distinction (bidi-char types) is governing;
---~ 2. Assuming that 'ARAB' represents an actual arabic string in raw input order, not word-order;
---~ 3. Assuming that 'BARA' represent the correct RL word order;
---~
---~ Then we have, with input: LATIN ARAB
---~
---~ \textdir TLT LATIN ARAB => LATIN BARA
---~ \textdir TRT LATIN ARAB => LATIN BARA
---~ \textdir TRT LRO LATIN ARAB => LATIN ARAB
---~ \textdir TLT LRO LATIN ARAB => LATIN ARAB
---~ \textdir TLT RLO LATIN ARAB => NITAL ARAB
---~ \textdir TRT RLO LATIN ARAB => NITAL ARAB
-
--- elseif d == "es" then -- European Number Separator
--- elseif d == "et" then -- European Number Terminator
--- elseif d == "cs" then -- Common Number Separator
--- elseif d == "nsm" then -- Non-Spacing Mark
--- elseif d == "bn" then -- Boundary Neutral
--- elseif d == "b" then -- Paragraph Separator
--- elseif d == "s" then -- Segment Separator
--- elseif d == "ws" then -- Whitespace
--- elseif d == "on" then -- Other Neutrals
-
-typesetters.directions = typesetters.directions or { }
-local directions = typesetters.directions
-
-local a_state = attributes.private('state')
-local a_directions = attributes.private('directions')
-
-local skipmath = true
-local strip = false
-
--- todo: delayed inserts here
--- todo: get rid of local functions here
-
--- beware, math adds whatsits afterwards so that will mess things up
-
-local finish, autodir, embedded, override, done = nil, 0, 0, 0, false
-local list, glyphs = nil, false
-local finished, finidir, finipos = nil, nil, 1
-local head, current, inserted = nil, nil, nil
-
-local function finish_auto_before()
- head, inserted = insert_node_before(head,current,new_textdir("-"..finish))
- finished, finidir = inserted, finish
- if trace_directions then
- insert(list,#list,format("auto finish inserted before: %s",finish))
- finipos = #list-1
- end
- finish, autodir, done = nil, 0, true
-end
-
-local function finish_auto_after()
- head, current = insert_node_after(head,current,new_textdir("-"..finish))
- finished, finidir = current, finish
- if trace_directions then
- list[#list+1] = format("auto finish inserted after: %s",finish)
- finipos = #list
- end
- finish, autodir, done = nil, 0, true
-end
-
-local function force_auto_left_before()
- if finish then
- finish_auto_before()
- end
- if embedded >= 0 then
- finish, autodir, done = "TLT", 1, true
- else
- finish, autodir, done = "TRT", -1, true
- end
- if finidir == finish then
- head = remove_node(head,finished,true)
- if trace_directions then
- list[finipos] = list[finipos] .. " (deleted afterwards)"
- insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
- end
- else
- head, inserted = insert_node_before(head,current,new_textdir("+"..finish))
- if trace_directions then
- insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
- end
- end
-end
-
-local function force_auto_right_before()
- if finish then
- finish_auto_before()
- end
- if embedded <= 0 then
- finish, autodir, done = "TRT", -1, true
- else
- finish, autodir, done = "TLT", 1, true
- end
- if finidir == finish then
- head = remove_node(head,finished,true)
- if trace_directions then
- list[finipos] = list[finipos] .. " (deleted afterwards)"
- insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
- end
- else
- head, inserted = insert_node_before(head,current,new_textdir("+"..finish))
- if trace_directions then
- insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded))
- end
- end
-end
-
--- todo: use new dir functions
-
-local s_isol = fonts.analyzers.states.isol
-
-function directions.process(namespace,attribute,start) -- todo: make faster
- if not start.next then
- return start, false
- end
- head, current, inserted = start, start, nil
- finish, autodir, embedded, override, done = nil, 0, 0, 0, false
- list, glyphs = trace_directions and { }, false
- finished, finidir, finipos = nil, nil, 1
- local stack, top, obsolete = { }, 0, { }
- local lro, rlo, prevattr, inmath = false, false, 0, false
- while current do
- local id = current.id
- if skipmath and id == math_code then
- local subtype = current.subtype
- if subtype == beginmath_code then
- inmath = true
- elseif subtype == endmath_code then
- inmath = false
- else
- -- todo
- end
- current = current.next
- elseif inmath then
- current = current.next
- else
- local attr = current[attribute]
- if attr and attr > 0 then
- -- current[attribute] = unsetvalue -- slow, needed?
- if attr == 1 then
- -- bidi parsing mode
- elseif attr ~= prevattr then
- -- no pop, grouped driven (2=normal,3=lro,4=rlo)
- if attr == 3 then
- if trace_directions then
- list[#list+1] = format("override right -> left (lro) (bidi=%s)",attr)
- end
- lro, rlo = true, false
- elseif attr == 4 then
- if trace_directions then
- list[#list+1] = format("override left -> right (rlo) (bidi=%s)",attr)
- end
- lro, rlo = false, true
- else
- if trace_directions and
- current ~= head then list[#list+1] = format("override reset (bidi=%s)",attr)
- end
- lro, rlo = false, false
- end
- prevattr = attr
- end
- end
- if id == glyph_code then
- glyphs = true
- if attr and attr > 0 then
- local char = current.char
- local d = chardirs[char]
- if rlo or override > 0 then
- if d == "l" then
- if trace_directions then
- list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to r (bidi=%s)",utfchar(char),char,char,d,attr)
- end
- d = "r"
- elseif trace_directions then
- if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
- list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
- else -- todo: rle lre
- list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
- end
- end
- elseif lro or override < 0 then
- if d == "r" or d == "al" then
- current[a_state] = s_isol -- maybe better have a special bidi attr value -> override (9) -> todo
- if trace_directions then
- list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to l (bidi=%s) (state=isol)",utfchar(char),char,char,d,attr)
- end
- d = "l"
- elseif trace_directions then
- if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
- list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
- else -- todo: rle lre
- list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
- end
- end
- elseif trace_directions then
- if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal
- list[#list+1] = format("override char of class %s (bidi=%s)",d,attr)
- else -- todo: rle lre
- list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr)
- end
- end
- if d == "on" then
- local mirror = chardata[char].mirror -- maybe make a special mirror table
- if mirror and fontchar[current.font][mirror] then
- -- todo: set attribute
- if autodir < 0 then
- current.char = mirror
- done = true
- --~ elseif left or autodir > 0 then
- --~ if not is_right(current.prev) then
- --~ current.char = mirror
- --~ done = true
- --~ end
- end
- end
- elseif d == "l" or d == "en" then -- european number
- if autodir <= 0 then -- could be option
- force_auto_left_before()
- end
- elseif d == "r" or d == "al" then -- arabic number
- if autodir >= 0 then
- force_auto_right_before()
- end
- elseif d == "an" then -- arabic number
- -- actually this is language dependent ...
--- if autodir <= 0 then
--- force_auto_left_before()
--- end
- if autodir >= 0 then
- force_auto_right_before()
- end
- elseif d == "lro" then -- Left-to-Right Override -> right becomes left
- if trace_directions then
- list[#list+1] = "override right -> left"
- end
- top = top + 1
- stack[top] = { override, embedded }
- override = -1
- obsolete[#obsolete+1] = current
- elseif d == "rlo" then -- Right-to-Left Override -> left becomes right
- if trace_directions then
- list[#list+1] = "override left -> right"
- end
- top = top + 1
- stack[top] = { override, embedded }
- override = 1
- obsolete[#obsolete+1] = current
- elseif d == "lre" then -- Left-to-Right Embedding -> TLT
- if trace_directions then
- list[#list+1] = "embedding left -> right"
- end
- top = top + 1
- stack[top] = { override, embedded }
- embedded = 1
- obsolete[#obsolete+1] = current
- elseif d == "rle" then -- Right-to-Left Embedding -> TRT
- if trace_directions then
- list[#list+1] = "embedding right -> left"
- end
- top = top + 1
- stack[top] = { override, embedded }
- embedded = -1 -- was 1
- obsolete[#obsolete+1] = current
- elseif d == "pdf" then -- Pop Directional Format
- -- override = 0
- if top > 0 then
- local s = stack[top]
- override, embedded = s[1], s[2]
- top = top - 1
- if trace_directions then
- list[#list+1] = format("state: override: %s, embedded: %s, autodir: %s",override,embedded,autodir)
- end
- else
- if trace_directions then
- list[#list+1] = "pop (error, too many pops)"
- end
- end
- obsolete[#obsolete+1] = current
- end
- elseif trace_directions then
- local char = current.char
- local d = chardirs[char]
- list[#list+1] = format("char %s (%s / U+%04X) of class %s (no bidi)",utfchar(char),char,char,d or "?")
- end
- elseif id == whatsit_code then
- if finish then
- finish_auto_before()
- end
- local subtype = current.subtype
- if subtype == localpar_code then
- local dir = current.dir
- local d = sub(dir,2,2)
- if d == 'R' then -- find(dir,".R.") / dir == "TRT"
- autodir = -1
- else
- autodir = 1
- end
- -- embedded = autodir
- if trace_directions then
- list[#list+1] = format("pardir %s",dir)
- end
- elseif subtype == dir_code then
- local dir = current.dir
- -- local sign = sub(dir,1,1)
- -- local dire = sub(dir,3,3)
- local sign, dire = match(dir,"^(.).(.)")
- if dire == "R" then
- if sign == "+" then
- finish, autodir = "TRT", -1
- else
- finish, autodir = nil, 0
- end
- else
- if sign == "+" then
- finish, autodir = "TLT", 1
- else
- finish, autodir = nil, 0
- end
- end
- if trace_directions then
- list[#list+1] = format("textdir %s",dir)
- end
- end
- else
- if trace_directions then
- list[#list+1] = format("node %s (subtype %s)",nodecodes[id],current.subtype)
- end
- if finish then
- finish_auto_before()
- end
- end
- local cn = current.next
- if not cn then
- if finish then
- finish_auto_after()
- end
- end
- current = cn
- end
- end
- if trace_directions and glyphs then
- report_directions("start log")
- for i=1,#list do
- report_directions("%02i: %s",i,list[i])
- end
- report_directions("stop log")
- end
- if done and strip then
- local n = #obsolete
- if n > 0 then
- for i=1,n do
- remove_node(head,obsolete[i],true)
- end
- report_directions("%s character nodes removed",n)
- end
- end
- return head, done
-end
-
---~ local function is_right(n) -- keep !
---~ if n then
---~ local id = n.id
---~ if id == glyph_code then
---~ local attr = n[attribute]
---~ if attr and attr > 0 then
---~ local d = chardirs[n.char]
---~ if d == "r" or d == "al" then -- override
---~ return true
---~ end
---~ end
---~ end
---~ end
---~ return false
---~ end
-
---~ function directions.enable()
---~ tasks.enableaction("processors","directions.handler")
---~ end
-
-local enabled = false
-
-function directions.set(n) -- todo: names and numbers
- if not enabled then
- if trace_directions then
- report_breakpoints("enabling directions handler")
- end
- tasks.enableaction("processors","typesetters.directions.handler")
- enabled = true
- end
- if not n or n == 0 then
- n = unsetvalue
- -- maybe tracing
- end
- texattribute[a_directions] = n
-end
-
-commands.setdirection = directions.set
-
-directions.handler = nodes.installattributehandler {
- name = "directions",
- namespace = directions,
- processor = directions.process,
-}
+if not modules then modules = { } end modules ['typo-dir'] = { + version = 1.001, + comment = "companion to typo-dir.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +-- todo: also use end_of_math here? + +local next, type = next, type +local format, insert, sub, find, match = string.format, table.insert, string.sub, string.find, string.match +local utfchar = utf.char + +-- vertical space handler + +local nodes, node = nodes, node + +local trace_directions = false trackers.register("typesetters.directions", function(v) trace_directions = v end) + +local report_directions = logs.reporter("typesetting","directions") + +local traverse_id = node.traverse_id +local insert_node_before = node.insert_before +local insert_node_after = node.insert_after +local remove_node = nodes.remove + +local texattribute = tex.attribute +local unsetvalue = attributes.unsetvalue + +local nodecodes = nodes.nodecodes +local whatcodes = nodes.whatcodes +local mathcodes = nodes.mathcodes + +local tasks = nodes.tasks + +local glyph_code = nodecodes.glyph +local whatsit_code = nodecodes.whatsit +local math_code = nodecodes.math + +local localpar_code = whatcodes.localpar +local dir_code = whatcodes.dir + +local nodepool = nodes.pool + +local new_textdir = nodepool.textdir + +local beginmath_code = mathcodes.beginmath +local endmath_code = mathcodes.endmath + +local fonthashes = fonts.hashes +local fontdata = fonthashes.identifiers +local fontchar = fonthashes.characters + +local chardata = characters.data +local chardirs = characters.directions -- maybe make a special mirror table + +--~ Analysis by Idris: +--~ +--~ 1. Assuming the reading- vs word-order distinction (bidi-char types) is governing; +--~ 2. Assuming that 'ARAB' represents an actual arabic string in raw input order, not word-order; +--~ 3. Assuming that 'BARA' represent the correct RL word order; +--~ +--~ Then we have, with input: LATIN ARAB +--~ +--~ \textdir TLT LATIN ARAB => LATIN BARA +--~ \textdir TRT LATIN ARAB => LATIN BARA +--~ \textdir TRT LRO LATIN ARAB => LATIN ARAB +--~ \textdir TLT LRO LATIN ARAB => LATIN ARAB +--~ \textdir TLT RLO LATIN ARAB => NITAL ARAB +--~ \textdir TRT RLO LATIN ARAB => NITAL ARAB + +-- elseif d == "es" then -- European Number Separator +-- elseif d == "et" then -- European Number Terminator +-- elseif d == "cs" then -- Common Number Separator +-- elseif d == "nsm" then -- Non-Spacing Mark +-- elseif d == "bn" then -- Boundary Neutral +-- elseif d == "b" then -- Paragraph Separator +-- elseif d == "s" then -- Segment Separator +-- elseif d == "ws" then -- Whitespace +-- elseif d == "on" then -- Other Neutrals + +typesetters.directions = typesetters.directions or { } +local directions = typesetters.directions + +local a_state = attributes.private('state') +local a_directions = attributes.private('directions') + +local skipmath = true +local strip = false + +-- todo: delayed inserts here +-- todo: get rid of local functions here + +-- beware, math adds whatsits afterwards so that will mess things up + +local finish, autodir, embedded, override, done = nil, 0, 0, 0, false +local list, glyphs = nil, false +local finished, finidir, finipos = nil, nil, 1 +local head, current, inserted = nil, nil, nil + +local function finish_auto_before() + head, inserted = insert_node_before(head,current,new_textdir("-"..finish)) + finished, finidir = inserted, finish + if trace_directions then + insert(list,#list,format("auto finish inserted before: %s",finish)) + finipos = #list-1 + end + finish, autodir, done = nil, 0, true +end + +local function finish_auto_after() + head, current = insert_node_after(head,current,new_textdir("-"..finish)) + finished, finidir = current, finish + if trace_directions then + list[#list+1] = format("auto finish inserted after: %s",finish) + finipos = #list + end + finish, autodir, done = nil, 0, true +end + +local function force_auto_left_before() + if finish then + finish_auto_before() + end + if embedded >= 0 then + finish, autodir, done = "TLT", 1, true + else + finish, autodir, done = "TRT", -1, true + end + if finidir == finish then + head = remove_node(head,finished,true) + if trace_directions then + list[finipos] = list[finipos] .. " (deleted afterwards)" + insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded)) + end + else + head, inserted = insert_node_before(head,current,new_textdir("+"..finish)) + if trace_directions then + insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded)) + end + end +end + +local function force_auto_right_before() + if finish then + finish_auto_before() + end + if embedded <= 0 then + finish, autodir, done = "TRT", -1, true + else + finish, autodir, done = "TLT", 1, true + end + if finidir == finish then + head = remove_node(head,finished,true) + if trace_directions then + list[finipos] = list[finipos] .. " (deleted afterwards)" + insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded)) + end + else + head, inserted = insert_node_before(head,current,new_textdir("+"..finish)) + if trace_directions then + insert(list,#list,format("start text dir %s (embedded: %s)",finish,embedded)) + end + end +end + +-- todo: use new dir functions + +local s_isol = fonts.analyzers.states.isol + +function directions.process(namespace,attribute,start) -- todo: make faster + if not start.next then + return start, false + end + head, current, inserted = start, start, nil + finish, autodir, embedded, override, done = nil, 0, 0, 0, false + list, glyphs = trace_directions and { }, false + finished, finidir, finipos = nil, nil, 1 + local stack, top, obsolete = { }, 0, { } + local lro, rlo, prevattr, inmath = false, false, 0, false + while current do + local id = current.id + if skipmath and id == math_code then + local subtype = current.subtype + if subtype == beginmath_code then + inmath = true + elseif subtype == endmath_code then + inmath = false + else + -- todo + end + current = current.next + elseif inmath then + current = current.next + else + local attr = current[attribute] + if attr and attr > 0 then + -- current[attribute] = unsetvalue -- slow, needed? + if attr == 1 then + -- bidi parsing mode + elseif attr ~= prevattr then + -- no pop, grouped driven (2=normal,3=lro,4=rlo) + if attr == 3 then + if trace_directions then + list[#list+1] = format("override right -> left (lro) (bidi=%s)",attr) + end + lro, rlo = true, false + elseif attr == 4 then + if trace_directions then + list[#list+1] = format("override left -> right (rlo) (bidi=%s)",attr) + end + lro, rlo = false, true + else + if trace_directions and + current ~= head then list[#list+1] = format("override reset (bidi=%s)",attr) + end + lro, rlo = false, false + end + prevattr = attr + end + end + if id == glyph_code then + glyphs = true + if attr and attr > 0 then + local char = current.char + local d = chardirs[char] + if rlo or override > 0 then + if d == "l" then + if trace_directions then + list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to r (bidi=%s)",utfchar(char),char,char,d,attr) + end + d = "r" + elseif trace_directions then + if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal + list[#list+1] = format("override char of class %s (bidi=%s)",d,attr) + else -- todo: rle lre + list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr) + end + end + elseif lro or override < 0 then + if d == "r" or d == "al" then + current[a_state] = s_isol -- maybe better have a special bidi attr value -> override (9) -> todo + if trace_directions then + list[#list+1] = format("char %s (%s / U+%04X) of class %s overidden to l (bidi=%s) (state=isol)",utfchar(char),char,char,d,attr) + end + d = "l" + elseif trace_directions then + if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal + list[#list+1] = format("override char of class %s (bidi=%s)",d,attr) + else -- todo: rle lre + list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr) + end + end + elseif trace_directions then + if d == "lro" or d == "rlo" or d == "pdf" then -- else side effects on terminal + list[#list+1] = format("override char of class %s (bidi=%s)",d,attr) + else -- todo: rle lre + list[#list+1] = format("char %s (%s / U+%04X) of class %s (bidi=%s)",utfchar(char),char,char,d,attr) + end + end + if d == "on" then + local mirror = chardata[char].mirror -- maybe make a special mirror table + if mirror and fontchar[current.font][mirror] then + -- todo: set attribute + if autodir < 0 then + current.char = mirror + done = true + --~ elseif left or autodir > 0 then + --~ if not is_right(current.prev) then + --~ current.char = mirror + --~ done = true + --~ end + end + end + elseif d == "l" or d == "en" then -- european number + if autodir <= 0 then -- could be option + force_auto_left_before() + end + elseif d == "r" or d == "al" then -- arabic number + if autodir >= 0 then + force_auto_right_before() + end + elseif d == "an" then -- arabic number + -- actually this is language dependent ... +-- if autodir <= 0 then +-- force_auto_left_before() +-- end + if autodir >= 0 then + force_auto_right_before() + end + elseif d == "lro" then -- Left-to-Right Override -> right becomes left + if trace_directions then + list[#list+1] = "override right -> left" + end + top = top + 1 + stack[top] = { override, embedded } + override = -1 + obsolete[#obsolete+1] = current + elseif d == "rlo" then -- Right-to-Left Override -> left becomes right + if trace_directions then + list[#list+1] = "override left -> right" + end + top = top + 1 + stack[top] = { override, embedded } + override = 1 + obsolete[#obsolete+1] = current + elseif d == "lre" then -- Left-to-Right Embedding -> TLT + if trace_directions then + list[#list+1] = "embedding left -> right" + end + top = top + 1 + stack[top] = { override, embedded } + embedded = 1 + obsolete[#obsolete+1] = current + elseif d == "rle" then -- Right-to-Left Embedding -> TRT + if trace_directions then + list[#list+1] = "embedding right -> left" + end + top = top + 1 + stack[top] = { override, embedded } + embedded = -1 -- was 1 + obsolete[#obsolete+1] = current + elseif d == "pdf" then -- Pop Directional Format + -- override = 0 + if top > 0 then + local s = stack[top] + override, embedded = s[1], s[2] + top = top - 1 + if trace_directions then + list[#list+1] = format("state: override: %s, embedded: %s, autodir: %s",override,embedded,autodir) + end + else + if trace_directions then + list[#list+1] = "pop (error, too many pops)" + end + end + obsolete[#obsolete+1] = current + end + elseif trace_directions then + local char = current.char + local d = chardirs[char] + list[#list+1] = format("char %s (%s / U+%04X) of class %s (no bidi)",utfchar(char),char,char,d or "?") + end + elseif id == whatsit_code then + if finish then + finish_auto_before() + end + local subtype = current.subtype + if subtype == localpar_code then + local dir = current.dir + local d = sub(dir,2,2) + if d == 'R' then -- find(dir,".R.") / dir == "TRT" + autodir = -1 + else + autodir = 1 + end + -- embedded = autodir + if trace_directions then + list[#list+1] = format("pardir %s",dir) + end + elseif subtype == dir_code then + local dir = current.dir + -- local sign = sub(dir,1,1) + -- local dire = sub(dir,3,3) + local sign, dire = match(dir,"^(.).(.)") + if dire == "R" then + if sign == "+" then + finish, autodir = "TRT", -1 + else + finish, autodir = nil, 0 + end + else + if sign == "+" then + finish, autodir = "TLT", 1 + else + finish, autodir = nil, 0 + end + end + if trace_directions then + list[#list+1] = format("textdir %s",dir) + end + end + else + if trace_directions then + list[#list+1] = format("node %s (subtype %s)",nodecodes[id],current.subtype) + end + if finish then + finish_auto_before() + end + end + local cn = current.next + if not cn then + if finish then + finish_auto_after() + end + end + current = cn + end + end + if trace_directions and glyphs then + report_directions("start log") + for i=1,#list do + report_directions("%02i: %s",i,list[i]) + end + report_directions("stop log") + end + if done and strip then + local n = #obsolete + if n > 0 then + for i=1,n do + remove_node(head,obsolete[i],true) + end + report_directions("%s character nodes removed",n) + end + end + return head, done +end + +--~ local function is_right(n) -- keep ! +--~ if n then +--~ local id = n.id +--~ if id == glyph_code then +--~ local attr = n[attribute] +--~ if attr and attr > 0 then +--~ local d = chardirs[n.char] +--~ if d == "r" or d == "al" then -- override +--~ return true +--~ end +--~ end +--~ end +--~ end +--~ return false +--~ end + +--~ function directions.enable() +--~ tasks.enableaction("processors","directions.handler") +--~ end + +local enabled = false + +function directions.set(n) -- todo: names and numbers + if not enabled then + if trace_directions then + report_breakpoints("enabling directions handler") + end + tasks.enableaction("processors","typesetters.directions.handler") + enabled = true + end + if not n or n == 0 then + n = unsetvalue + -- maybe tracing + end + texattribute[a_directions] = n +end + +commands.setdirection = directions.set + +directions.handler = nodes.installattributehandler { + name = "directions", + namespace = directions, + processor = directions.process, +} |