diff options
Diffstat (limited to 'tex/context/base/lpdf-tag.lua')
| -rw-r--r-- | tex/context/base/lpdf-tag.lua | 626 |
1 files changed, 313 insertions, 313 deletions
diff --git a/tex/context/base/lpdf-tag.lua b/tex/context/base/lpdf-tag.lua index 8cdb5f6a4..f5766996c 100644 --- a/tex/context/base/lpdf-tag.lua +++ b/tex/context/base/lpdf-tag.lua @@ -1,313 +1,313 @@ -if not modules then modules = { } end modules ['lpdf-tag'] = { - version = 1.001, - comment = "companion to lpdf-tag.mkiv", - author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", - copyright = "PRAGMA ADE / ConTeXt Development Team", - license = "see context related readme files" -} - -local format, match, concat = string.format, string.match, table.concat -local lpegmatch = lpeg.match -local utfchar = utf.char - -local trace_tags = false trackers.register("structures.tags", function(v) trace_tags = v end) - -local report_tags = logs.reporter("backend","tags") - -local backends, lpdf, nodes = backends, lpdf, nodes - -local nodeinjections = backends.pdf.nodeinjections -local codeinjections = backends.pdf.codeinjections - -local tasks = nodes.tasks - -local pdfdictionary = lpdf.dictionary -local pdfarray = lpdf.array -local pdfboolean = lpdf.boolean -local pdfconstant = lpdf.constant -local pdfreference = lpdf.reference -local pdfunicode = lpdf.unicode -local pdfstring = lpdf.string -local pdfflushobject = lpdf.flushobject -local pdfreserveobject = lpdf.reserveobject -local pdfpagereference = lpdf.pagereference - -local nodepool = nodes.pool - -local pdfliteral = nodepool.pdfliteral - -local nodecodes = nodes.nodecodes - -local hlist_code = nodecodes.hlist -local vlist_code = nodecodes.vlist -local glyph_code = nodecodes.glyph - -local a_tagged = attributes.private('tagged') -local a_image = attributes.private('image') - -local traverse_nodes = node.traverse -local traverse_id = node.traverse_id -local tosequence = nodes.tosequence -local copy_node = node.copy -local slide_nodelist = node.slide - -local structure_stack = { } -local structure_kids = pdfarray() -local structure_ref = pdfreserveobject() -local parent_ref = pdfreserveobject() -local root = { pref = pdfreference(structure_ref), kids = structure_kids } -local tree = { } -local elements = { } -local names = pdfarray() -local taglist = structures.tags.taglist -local usedlabels = structures.tags.labels -local properties = structures.tags.properties -local usedmapping = { } - -local colonsplitter = lpeg.splitat(":") -local dashsplitter = lpeg.splitat("-") - -local add_ids = false -- true - - ---~ function codeinjections.maptag(original,target,kind) ---~ mapping[original] = { target, kind or "inline" } ---~ end - -local function finishstructure() - if #structure_kids > 0 then - local nums, n = pdfarray(), 0 - for i=1,#tree do - n = n + 1 ; nums[n] = i-1 - n = n + 1 ; nums[n] = pdfreference(pdfflushobject(tree[i])) - end - local parenttree = pdfdictionary { - Nums = nums - } - -- we need to split names into smaller parts (e.g. alphabetic or so) - if add_ids then - local kids = pdfdictionary { - Limits = pdfarray { names[1], names[#names-1] }, - Names = names, - } - local idtree = pdfdictionary { - Kids = pdfarray { pdfreference(pdfflushobject(kids)) }, - } - end - -- - local rolemap = pdfdictionary() - for k, v in next, usedmapping do - k = usedlabels[k] or k - local p = properties[k] - rolemap[k] = pdfconstant(p and p.pdf or "Span") -- or "Div" - end - local structuretree = pdfdictionary { - Type = pdfconstant("StructTreeRoot"), - K = pdfreference(pdfflushobject(structure_kids)), - ParentTree = pdfreference(pdfflushobject(parent_ref,parenttree)), - IDTree = (add_ids and pdfreference(pdfflushobject(idtree))) or nil, - RoleMap = rolemap, - } - pdfflushobject(structure_ref,structuretree) - lpdf.addtocatalog("StructTreeRoot",pdfreference(structure_ref)) - -- - local markinfo = pdfdictionary { - Marked = pdfboolean(true), - -- UserProperties = pdfboolean(true), - -- Suspects = pdfboolean(true), - } - lpdf.addtocatalog("MarkInfo",pdfreference(pdfflushobject(markinfo))) - -- - for fulltag, element in next, elements do - pdfflushobject(element.knum,element.kids) - end - end -end - -lpdf.registerdocumentfinalizer(finishstructure,"document structure") - -local index, pageref, pagenum, list = 0, nil, 0, nil - -local pdf_mcr = pdfconstant("MCR") -local pdf_struct_element = pdfconstant("StructElem") - -local function initializepage() - index = 0 - pagenum = tex.count.realpageno - pageref = pdfreference(pdfpagereference(pagenum)) - list = pdfarray() - tree[pagenum] = list -- we can flush after done, todo -end - -local function finishpage() - -- flush what can be flushed - lpdf.addtopageattributes("StructParents",pagenum-1) -end - --- here we can flush and free elements that are finished - -local function makeelement(fulltag,parent) - local tag, n = lpegmatch(dashsplitter,fulltag) - local tg, detail = lpegmatch(colonsplitter,tag) - local k, r = pdfarray(), pdfreserveobject() - usedmapping[tg] = true - tg = usedlabels[tg] or tg - local d = pdfdictionary { - Type = pdf_struct_element, - S = pdfconstant(tg), - ID = (add_ids and fulltag) or nil, - T = detail and detail or nil, - P = parent.pref, - Pg = pageref, - K = pdfreference(r), - -- Alt = " Who cares ", - -- ActualText = " Hi Hans ", - } - local s = pdfreference(pdfflushobject(d)) - if add_ids then - names[#names+1] = fulltag - names[#names+1] = s - end - local kids = parent.kids - kids[#kids+1] = s - elements[fulltag] = { tag = tag, pref = s, kids = k, knum = r, pnum = pagenum } -end - -local function makecontent(parent,start,stop,slist,id) - local tag, kids = parent.tag, parent.kids - local last = index - if id == "image" then - local d = pdfdictionary { - Type = pdf_mcr, - Pg = pageref, - MCID = last, - Alt = "image", - } - kids[#kids+1] = d - elseif pagenum == parent.pnum then - kids[#kids+1] = last - else - local d = pdfdictionary { - Type = pdf_mcr, - Pg = pageref, - MCID = last, - } - -- kids[#kids+1] = pdfreference(pdfflushobject(d)) - kids[#kids+1] = d - end - -- - local bliteral = pdfliteral(format("/%s <</MCID %s>>BDC",tag,last)) - local prev = start.prev - if prev then - prev.next, bliteral.prev = bliteral, prev - end - start.prev, bliteral.next = bliteral, start - if slist and slist.list == start then - slist.list = bliteral - elseif not prev then - report_tags("this can't happen: injection in front of nothing") - end - -- - local eliteral = pdfliteral("EMC") - local next = stop.next - if next then - next.prev, eliteral.next = eliteral, next - end - stop.next, eliteral.prev = eliteral, stop - -- - index = index + 1 - list[index] = parent.pref - return bliteral, eliteral -end - --- -- -- - -local level, last, ranges, range = 0, nil, { }, nil - -local function collectranges(head,list) - for n in traverse_nodes(head) do - local id = n.id -- 14: image, 8: literal (mp) - if id == glyph_code then - local at = n[a_tagged] - if not at then - range = nil - elseif last ~= at then - range = { at, "glyph", n, n, list } -- attr id start stop list - ranges[#ranges+1] = range - last = at - elseif range then - range[4] = n -- stop - end - elseif id == hlist_code or id == vlist_code then - local at = n[a_image] - if at then - local at = n[a_tagged] - if not at then - range = nil - else - ranges[#ranges+1] = { at, "image", n, n, list } -- attr id start stop list - end - last = nil - else - local nl = n.list - slide_nodelist(nl) -- temporary hack till math gets slided (tracker item) - collectranges(nl,n) - end - end - end -end - -function nodeinjections.addtags(head) - -- no need to adapt head, as we always operate on lists - level, last, ranges, range = 0, nil, { }, nil - initializepage() - collectranges(head) - if trace_tags then - for i=1,#ranges do - local range = ranges[i] - local attr, id, start, stop = range[1], range[2], range[3], range[4] - local tags = taglist[attr] - if tags then -- not ok ... only first lines - report_tags("%s => %s : %05i % t",tosequence(start,start),tosequence(stop,stop),attr,tags) - end - end - end - for i=1,#ranges do - local range = ranges[i] - local attr, id, start, stop, list = range[1], range[2], range[3], range[4], range[5] - local tags = taglist[attr] - local prev = root - local noftags, tag = #tags, nil - for j=1,noftags do - local tag = tags[j] - if not elements[tag] then - makeelement(tag,prev) - end - prev = elements[tag] - end - local b, e = makecontent(prev,start,stop,list,id) - if start == head then - report_tags("this can't happen: parent list gets tagged") - head = b - end - end - finishpage() - -- can be separate feature - -- - -- injectspans(head) -- does to work yet - -- - return head, true -end - --- this belongs elsewhere (export is not pdf related) - -function codeinjections.enabletags(tg,lb) - structures.tags.handler = nodeinjections.addtags - tasks.enableaction("shipouts","structures.tags.handler") - tasks.enableaction("shipouts","nodes.handlers.accessibility") - tasks.enableaction("math","noads.handlers.tags") - -- maybe also textblock - if trace_tags then - report_tags("enabling structure tags") - end -end +if not modules then modules = { } end modules ['lpdf-tag'] = {
+ version = 1.001,
+ comment = "companion to lpdf-tag.mkiv",
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+local format, match, concat = string.format, string.match, table.concat
+local lpegmatch = lpeg.match
+local utfchar = utf.char
+
+local trace_tags = false trackers.register("structures.tags", function(v) trace_tags = v end)
+
+local report_tags = logs.reporter("backend","tags")
+
+local backends, lpdf, nodes = backends, lpdf, nodes
+
+local nodeinjections = backends.pdf.nodeinjections
+local codeinjections = backends.pdf.codeinjections
+
+local tasks = nodes.tasks
+
+local pdfdictionary = lpdf.dictionary
+local pdfarray = lpdf.array
+local pdfboolean = lpdf.boolean
+local pdfconstant = lpdf.constant
+local pdfreference = lpdf.reference
+local pdfunicode = lpdf.unicode
+local pdfstring = lpdf.string
+local pdfflushobject = lpdf.flushobject
+local pdfreserveobject = lpdf.reserveobject
+local pdfpagereference = lpdf.pagereference
+
+local nodepool = nodes.pool
+
+local pdfliteral = nodepool.pdfliteral
+
+local nodecodes = nodes.nodecodes
+
+local hlist_code = nodecodes.hlist
+local vlist_code = nodecodes.vlist
+local glyph_code = nodecodes.glyph
+
+local a_tagged = attributes.private('tagged')
+local a_image = attributes.private('image')
+
+local traverse_nodes = node.traverse
+local traverse_id = node.traverse_id
+local tosequence = nodes.tosequence
+local copy_node = node.copy
+local slide_nodelist = node.slide
+
+local structure_stack = { }
+local structure_kids = pdfarray()
+local structure_ref = pdfreserveobject()
+local parent_ref = pdfreserveobject()
+local root = { pref = pdfreference(structure_ref), kids = structure_kids }
+local tree = { }
+local elements = { }
+local names = pdfarray()
+local taglist = structures.tags.taglist
+local usedlabels = structures.tags.labels
+local properties = structures.tags.properties
+local usedmapping = { }
+
+local colonsplitter = lpeg.splitat(":")
+local dashsplitter = lpeg.splitat("-")
+
+local add_ids = false -- true
+
+
+--~ function codeinjections.maptag(original,target,kind)
+--~ mapping[original] = { target, kind or "inline" }
+--~ end
+
+local function finishstructure()
+ if #structure_kids > 0 then
+ local nums, n = pdfarray(), 0
+ for i=1,#tree do
+ n = n + 1 ; nums[n] = i-1
+ n = n + 1 ; nums[n] = pdfreference(pdfflushobject(tree[i]))
+ end
+ local parenttree = pdfdictionary {
+ Nums = nums
+ }
+ -- we need to split names into smaller parts (e.g. alphabetic or so)
+ if add_ids then
+ local kids = pdfdictionary {
+ Limits = pdfarray { names[1], names[#names-1] },
+ Names = names,
+ }
+ local idtree = pdfdictionary {
+ Kids = pdfarray { pdfreference(pdfflushobject(kids)) },
+ }
+ end
+ --
+ local rolemap = pdfdictionary()
+ for k, v in next, usedmapping do
+ k = usedlabels[k] or k
+ local p = properties[k]
+ rolemap[k] = pdfconstant(p and p.pdf or "Span") -- or "Div"
+ end
+ local structuretree = pdfdictionary {
+ Type = pdfconstant("StructTreeRoot"),
+ K = pdfreference(pdfflushobject(structure_kids)),
+ ParentTree = pdfreference(pdfflushobject(parent_ref,parenttree)),
+ IDTree = (add_ids and pdfreference(pdfflushobject(idtree))) or nil,
+ RoleMap = rolemap,
+ }
+ pdfflushobject(structure_ref,structuretree)
+ lpdf.addtocatalog("StructTreeRoot",pdfreference(structure_ref))
+ --
+ local markinfo = pdfdictionary {
+ Marked = pdfboolean(true),
+ -- UserProperties = pdfboolean(true),
+ -- Suspects = pdfboolean(true),
+ }
+ lpdf.addtocatalog("MarkInfo",pdfreference(pdfflushobject(markinfo)))
+ --
+ for fulltag, element in next, elements do
+ pdfflushobject(element.knum,element.kids)
+ end
+ end
+end
+
+lpdf.registerdocumentfinalizer(finishstructure,"document structure")
+
+local index, pageref, pagenum, list = 0, nil, 0, nil
+
+local pdf_mcr = pdfconstant("MCR")
+local pdf_struct_element = pdfconstant("StructElem")
+
+local function initializepage()
+ index = 0
+ pagenum = tex.count.realpageno
+ pageref = pdfreference(pdfpagereference(pagenum))
+ list = pdfarray()
+ tree[pagenum] = list -- we can flush after done, todo
+end
+
+local function finishpage()
+ -- flush what can be flushed
+ lpdf.addtopageattributes("StructParents",pagenum-1)
+end
+
+-- here we can flush and free elements that are finished
+
+local function makeelement(fulltag,parent)
+ local tag, n = lpegmatch(dashsplitter,fulltag)
+ local tg, detail = lpegmatch(colonsplitter,tag)
+ local k, r = pdfarray(), pdfreserveobject()
+ usedmapping[tg] = true
+ tg = usedlabels[tg] or tg
+ local d = pdfdictionary {
+ Type = pdf_struct_element,
+ S = pdfconstant(tg),
+ ID = (add_ids and fulltag) or nil,
+ T = detail and detail or nil,
+ P = parent.pref,
+ Pg = pageref,
+ K = pdfreference(r),
+ -- Alt = " Who cares ",
+ -- ActualText = " Hi Hans ",
+ }
+ local s = pdfreference(pdfflushobject(d))
+ if add_ids then
+ names[#names+1] = fulltag
+ names[#names+1] = s
+ end
+ local kids = parent.kids
+ kids[#kids+1] = s
+ elements[fulltag] = { tag = tag, pref = s, kids = k, knum = r, pnum = pagenum }
+end
+
+local function makecontent(parent,start,stop,slist,id)
+ local tag, kids = parent.tag, parent.kids
+ local last = index
+ if id == "image" then
+ local d = pdfdictionary {
+ Type = pdf_mcr,
+ Pg = pageref,
+ MCID = last,
+ Alt = "image",
+ }
+ kids[#kids+1] = d
+ elseif pagenum == parent.pnum then
+ kids[#kids+1] = last
+ else
+ local d = pdfdictionary {
+ Type = pdf_mcr,
+ Pg = pageref,
+ MCID = last,
+ }
+ -- kids[#kids+1] = pdfreference(pdfflushobject(d))
+ kids[#kids+1] = d
+ end
+ --
+ local bliteral = pdfliteral(format("/%s <</MCID %s>>BDC",tag,last))
+ local prev = start.prev
+ if prev then
+ prev.next, bliteral.prev = bliteral, prev
+ end
+ start.prev, bliteral.next = bliteral, start
+ if slist and slist.list == start then
+ slist.list = bliteral
+ elseif not prev then
+ report_tags("this can't happen: injection in front of nothing")
+ end
+ --
+ local eliteral = pdfliteral("EMC")
+ local next = stop.next
+ if next then
+ next.prev, eliteral.next = eliteral, next
+ end
+ stop.next, eliteral.prev = eliteral, stop
+ --
+ index = index + 1
+ list[index] = parent.pref
+ return bliteral, eliteral
+end
+
+-- -- --
+
+local level, last, ranges, range = 0, nil, { }, nil
+
+local function collectranges(head,list)
+ for n in traverse_nodes(head) do
+ local id = n.id -- 14: image, 8: literal (mp)
+ if id == glyph_code then
+ local at = n[a_tagged]
+ if not at then
+ range = nil
+ elseif last ~= at then
+ range = { at, "glyph", n, n, list } -- attr id start stop list
+ ranges[#ranges+1] = range
+ last = at
+ elseif range then
+ range[4] = n -- stop
+ end
+ elseif id == hlist_code or id == vlist_code then
+ local at = n[a_image]
+ if at then
+ local at = n[a_tagged]
+ if not at then
+ range = nil
+ else
+ ranges[#ranges+1] = { at, "image", n, n, list } -- attr id start stop list
+ end
+ last = nil
+ else
+ local nl = n.list
+ slide_nodelist(nl) -- temporary hack till math gets slided (tracker item)
+ collectranges(nl,n)
+ end
+ end
+ end
+end
+
+function nodeinjections.addtags(head)
+ -- no need to adapt head, as we always operate on lists
+ level, last, ranges, range = 0, nil, { }, nil
+ initializepage()
+ collectranges(head)
+ if trace_tags then
+ for i=1,#ranges do
+ local range = ranges[i]
+ local attr, id, start, stop = range[1], range[2], range[3], range[4]
+ local tags = taglist[attr]
+ if tags then -- not ok ... only first lines
+ report_tags("%s => %s : %05i % t",tosequence(start,start),tosequence(stop,stop),attr,tags)
+ end
+ end
+ end
+ for i=1,#ranges do
+ local range = ranges[i]
+ local attr, id, start, stop, list = range[1], range[2], range[3], range[4], range[5]
+ local tags = taglist[attr]
+ local prev = root
+ local noftags, tag = #tags, nil
+ for j=1,noftags do
+ local tag = tags[j]
+ if not elements[tag] then
+ makeelement(tag,prev)
+ end
+ prev = elements[tag]
+ end
+ local b, e = makecontent(prev,start,stop,list,id)
+ if start == head then
+ report_tags("this can't happen: parent list gets tagged")
+ head = b
+ end
+ end
+ finishpage()
+ -- can be separate feature
+ --
+ -- injectspans(head) -- does to work yet
+ --
+ return head, true
+end
+
+-- this belongs elsewhere (export is not pdf related)
+
+function codeinjections.enabletags(tg,lb)
+ structures.tags.handler = nodeinjections.addtags
+ tasks.enableaction("shipouts","structures.tags.handler")
+ tasks.enableaction("shipouts","nodes.handlers.accessibility")
+ tasks.enableaction("math","noads.handlers.tags")
+ -- maybe also textblock
+ if trace_tags then
+ report_tags("enabling structure tags")
+ end
+end
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