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Diffstat (limited to 'tex/context/base/page-mix.lua')
| -rw-r--r-- | tex/context/base/page-mix.lua | 642 |
1 files changed, 642 insertions, 0 deletions
diff --git a/tex/context/base/page-mix.lua b/tex/context/base/page-mix.lua new file mode 100644 index 000000000..be87b79a7 --- /dev/null +++ b/tex/context/base/page-mix.lua @@ -0,0 +1,642 @@ +if not modules then modules = { } end modules ['page-mix'] = { + version = 1.001, + comment = "companion to page-mix.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +-- inserts.getname(name) + +-- local node, tex = node, tex +-- local nodes, interfaces, utilities = nodes, interfaces, utilities +-- local trackers, logs, storage = trackers, logs, storage +-- local number, table = number, table + +local concat = table.concat + +local nodecodes = nodes.nodecodes +local gluecodes = nodes.gluecodes +local nodepool = nodes.pool + +local hlist_code = nodecodes.hlist +local vlist_code = nodecodes.vlist +local kern_code = nodecodes.kern +local glue_code = nodecodes.glue +local penalty_code = nodecodes.penalty +local insert_code = nodecodes.ins +local mark_code = nodecodes.mark + +local new_hlist = nodepool.hlist +local new_vlist = nodepool.vlist +local new_glue = nodepool.glue + +local hpack = node.hpack +local vpack = node.vpack +local freenode = node.free + +local texbox = tex.box +local texskip = tex.skip +local texdimen = tex.dimen +local points = number.points +local settings_to_hash = utilities.parsers.settings_to_hash + +local variables = interfaces.variables +local v_yes = variables.yes +local v_global = variables["global"] +local v_local = variables["local"] +local v_columns = variables.columns + +local trace_state = false trackers.register("mixedcolumns.trace", function(v) trace_state = v end) +local trace_detail = false trackers.register("mixedcolumns.detail", function(v) trace_detail = v end) + +local report_state = logs.reporter("mixed columns") + +pagebuilders = pagebuilders or { } +pagebuilders.mixedcolumns = pagebuilders.mixedcolumns or { } +local mixedcolumns = pagebuilders.mixedcolumns + +local forcedbreak = -123 + +-- initializesplitter(specification) +-- cleanupsplitter() + +-- Inserts complicate matters a lot. In order to deal with them well, we need to +-- distinguish several cases. +-- +-- (1) full page columns: firstcolumn, columns, lastcolumn, page +-- (2) mid page columns : firstcolumn, columns, lastcolumn, page +-- +-- We need to collect them accordingly. + +local function collectinserts(result,nxt,nxtid) + local inserts, currentskips, nextskips, inserttotal = { }, 0, 0, 0 + while nxt do + if nxtid == insert_code then + inserttotal = inserttotal + nxt.height + nxt.depth + local s = nxt.subtype +-- print(">>>",structures.inserts.getlocation(s)) + local c = inserts[s] + if not c then + c = { } + inserts[s] = c + local width = texskip[s].width + if not result.inserts[s] then + currentskips = currentskips + width + end + nextskips = nextskips + width + end + c[#c+1] = nxt + if trace_detail then + report_state("insert of class %s found",s) + end + elseif nxtid == mark_code then + if trace_detail then + report_state("mark found") + end + else + break + end + nxt = nxt.next + if nxt then + nxtid = nxt.id + else + break + end + end + return nxt, inserts, currentskips, nextskips, inserttotal +end + +local function appendinserts(ri,inserts) + for class, collected in next, inserts do + local ric = ri[class] + if not ric then + -- assign to collected + ri[class] = collected + else + -- append to collected + for j=1,#collected do + ric[#ric+1] = collected[j] + end + end + end +end + +local function discardtopglue(current,discarded) + while current do + local id = current.id + if id == glue_code or (id == penalty_code and current.penalty ~= forcedbreak) then + discarded[#discarded+1] = current + current = current.next + else + break + end + end + return current +end + +local function stripbottomglue(results,discarded) + local height = 0 + for i=1,#results do + local r = results[i] + local t = r.tail + while t and t ~= r.head do + local prev = t.prev + if not prev then + break + elseif t.id == penalty_code then + if t.penalty == forcedbreak then + break + else + discarded[#discarded+1] = t + r.tail = prev + t = prev + end + elseif t.id == glue_code then + discarded[#discarded+1] = t + r.height = r.height - t.spec.width + r.tail = prev + t = prev + else + break + end + end + if r.height > height then + height = r.height + end + end + return height +end + +local function setsplit(specification) -- a rather large function + local box = specification.box + if not box then + report_state("fatal error, no box") + return + end + local list = texbox[box] + if not list then + report_state("fatal error, no list") + return + end + local head = list.head or specification.originalhead + if not head then + report_state("fatal error, no head") + return + end + local discarded = { } + local originalhead = head + local originalwidth = specification.originalwidth or list.width + local originalheight = specification.originalheight or list.height + local current = head + local height = 0 + local depth = 0 + local skip = 0 + local options = settings_to_hash(specification.option or "") + local stripbottom = specification.alternative == v_local + local cycle = specification.cycle or 1 + local nofcolumns = specification.nofcolumns or 1 + if nofcolumns == 0 then + nofcolumns = 1 + end + local preheight = specification.preheight or 0 + local extra = specification.extra or 0 + local maxheight = specification.maxheight + local optimal = originalheight/nofcolumns + if specification.balance ~= v_yes then + optimal = maxheight + end + local target = optimal + extra + local overflow = target > maxheight - preheight + local threshold = specification.threshold or 0 + if overflow then + target = maxheight - preheight + end + if trace_state then + report_state("cycle: %s, maxheight: %s, preheight: %s, target: %s, overflow: %s, extra: %s", + cycle, points(maxheight),points(preheight),points(target),tostring(overflow),points(extra)) + end + local results = { } + for i=1,nofcolumns do + results[i] = { + head = false, + tail = false, + height = 0, + depth = 0, + inserts = { }, + delta = 0, + } + end + local column = 1 + local result = results[column] + local lasthead = nil + local rest = nil + local function gotonext() + if head == lasthead then + if trace_state then + report_state("empty column %s, needs more work",column) + end +rest = current +return false + else + lasthead = head + result.head = head + if current == head then + result.tail = head + else + result.tail = current.prev + end + result.height = height + result.depth = depth + end + head = current + height = 0 + depth = 0 + skip = 0 + if column == nofcolumns then + column = 0 -- nicer in trace + rest = head +-- lasthead = head + return false + else + column = column + 1 + result = results[column] + current = discardtopglue(current,discarded) + head = current +-- lasthead = head + return true + end + end + local function checked(advance) + local total = skip + height + depth + advance + local delta = total - target + if trace_detail then + local currentcolumn = column + local state + if delta > threshold then + result.delta = delta + if gotonext() then + state = "next" + else + state = "quit" + end + else + state = "same" + end + if trace_detail then + report_state("check > column %s, advance: %s, total: %s, target: %s => %s (height: %s, depth: %s, skip: %s)", + currentcolumn,points(advance),points(total),points(target),state,points(height),points(depth),points(skip)) + end + return state + else + if delta > threshold then + result.delta = delta + if gotonext() then + return "next" + else + return "quit" + end + else + return "same" + end + end + end + current = discardtopglue(current,discarded) + head = current + while current do + local id = current.id + local nxt = current.next + if id == hlist_code or id == vlist_code then + local nxtid = nxt and nxt.id + local inserts, currentskips, nextskips, inserttotal = nil, 0, 0, 0 + local advance = current.height -- + current.depth + if nxt and (nxtid == insert_code or nxtid == mark_code) then + nxt, inserts, localskips, insertskips, inserttotal = collectinserts(result,nxt,nxtid) + end + local state = checked(advance+inserttotal+currentskips) + if trace_state then + report_state('line > column %s, advance: %s, insert: %s, height: %s, state: %s', + column,points(advance),points(inserttotal),points(height),state) + end + if state == "quit" then + break + else + height = height + depth + skip + advance + inserttotal + if state == "next" then + height = height + nextskips + else + height = height + currentskips + end + end + depth = current.depth + skip = 0 + if inserts then + appendinserts(result.inserts,inserts) + end + elseif id == glue_code then + local advance = current.spec.width + if advance ~= 0 then + local state = checked(advance) + if trace_state then + report_state('glue > column %s, advance: %s, height: %s, state: %s', + column,points(advance),points(height),state) + end + if state == "quit" then + break + end + height = height + depth + skip + depth = 0 + skip = height > 0 and advance or 0 + end + elseif id == kern_code then + local advance = current.kern + if advance ~= 0 then + local state = checked(advance) + if trace_state then + report_state('kern > column %s, advance: %s, height: %s, state: %s', + column,points(advance),points(height),state) + end + if state == "quit" then + break + end + height = height + depth + skip + advance + depth = 0 + skip = 0 + end + elseif id == penalty_code then + local penalty = current.penalty + if penalty == 0 then + -- don't bother + elseif penalty == forcedbreak then + if gotonext() then + if trace_state then + report_state("cycle: %s, forced column break (same page)",cycle) + end + else + if trace_state then + report_state("cycle: %s, forced column break (next page)",cycle) + end + break + end + else + -- todo: nobreak etc ... we might need to backtrack so we need to remember + -- the last acceptable break + -- club and widow and such i.e. resulting penalties (if we care) + end + end + if nxt then + current = nxt + elseif head == lasthead then + -- to be checked but break needed as otherwise we have a loop + if trace_state then + report_state("quit as head is lasthead") + end + break + else + local r = results[column] + r.head = head + r.tail = current + r.height = height + r.depth = depth + break + end + end + if not current then + if trace_state then + report_state("nilling rest") + end + rest = nil + elseif rest == lasthead then + if trace_state then + report_state("nilling rest as rest is lasthead") + end + rest = nil + end + + if stripbottom then + local height = stripbottomglue(results,discarded) + if height > 0 then + target = height + end + end + + specification.results = results + specification.height = target + specification.originalheight = originalheight + specification.originalwidth = originalwidth + specification.originalhead = originalhead + specification.targetheight = target or 0 + specification.rest = rest + specification.overflow = overflow + specification.discarded = discarded + + texbox[specification.box].head = nil + + return specification +end + +function mixedcolumns.finalize(result) + if result then + local results = result.results + for i=1,result.nofcolumns do + local r = results[i] + local h = r.head + if h then + h.prev = nil + local t = r.tail + if t then + t.next = nil + else + h.next = nil + r.tail = h + end + for c, list in next, r.inserts do + local t = { } + for i=1,#list do + local l = list[i] + local h = new_hlist() + t[i] = h + h.head = l.head + h.height = l.height + h.depth = l.depth + l.head = nil + end + t[1].prev = nil -- needs checking + t[#t].next = nil -- needs checking + r.inserts[c] = t + end + end + end + end +end + +local splitruns = 0 + +local function report_deltas(result,str) + local t = { } + for i=1,result.nofcolumns do + t[#t+1] = points(result.results[i].delta or 0) + end + report_state("%s, cycles: %s, deltas: %s",str,result.cycle or 1,concat(t," | ")) +end + +function mixedcolumns.setsplit(specification) + splitruns = splitruns + 1 + if trace_state then + report_state("split run %s",splitruns) + end + local result = setsplit(specification) + if result then + if result.overflow then + if trace_state then + report_deltas(result,"overflow") + end + -- we might have some rest + elseif result.rest and specification.balance == v_yes then + local step = specification.step or 65536*2 + local cycle = 1 + local cycles = specification.cycles or 100 + while result.rest and cycle <= cycles do + specification.extra = cycle * step + result = setsplit(specification) or result + if trace_state then + report_state("cycle: %s.%s, original height: %s, total height: %s", + splitruns,cycle,points(result.originalheight),points(result.nofcolumns*result.targetheight)) + end + cycle = cycle + 1 + specification.cycle = cycle + end + if cycle > cycles then + report_deltas(result,"too many balancing cycles") + elseif trace_state then + report_deltas(result,"balanced") + end + elseif trace_state then + report_deltas(result,"done") + end + return result + elseif trace_state then + report_state("no result") + end +end + +local topskip_code = gluecodes.topskip +local baselineskip_code = gluecodes.baselineskip + +function mixedcolumns.getsplit(result,n) + if not result then + report_state("flush, column: %s, no result",n) + return + end + local r = result.results[n] + if not r then + report_state("flush, column: %s, empty",n) + end + local h = r.head + if not h then + return new_glue(result.originalwidth) + end + + if trace_state then + local id = h.id + if id == hlist_code then + report_state("flush, column: %s, top line: %s",n,nodes.toutf(h.list)) + else + report_state("flush, column: %s, head node: %s",n,nodecodes[id]) + end + end + + h.prev = nil -- move up + local strutht = result.strutht + local strutdp = result.strutdp + local lineheight = strutht + strutdp + + local v = new_vlist() + v.head = h + + -- local v = vpack(h,"exactly",height) + + v.width = result.originalwidth + if result.alternative == v_global then -- option + result.height = result.maxheight + end + v.height = lineheight * math.ceil(result.height/lineheight) - strutdp + v.depth = strutdp + + for c, list in next, r.inserts do + -- tex.setbox("global",c,vpack(nodes.concat(list))) + -- tex.setbox(c,vpack(nodes.concat(list))) + texbox[c] = vpack(nodes.concat(list)) + r.inserts[c] = nil + end + return v +end + +function mixedcolumns.getrest(result) + local rest = result and result.rest + result.rest = nil -- to be sure + return rest +end + +function mixedcolumns.getlist(result) + local originalhead = result and result.originalhead + result.originalhead = nil -- to be sure + return originalhead +end + +function mixedcolumns.cleanup(result) + local discarded = result.discarded + for i=1,#discarded do + freenode(discarded[i]) + end +end + +-- interface -- + +local result + +function commands.mixsetsplit(specification) + if result then + for k, v in next, specification do + result[k] = v + end + result = mixedcolumns.setsplit(result) + else + result = mixedcolumns.setsplit(specification) + end +end + +function commands.mixgetsplit(n) + if result then + context(mixedcolumns.getsplit(result,n)) + end +end + +function commands.mixfinalize() + if result then + mixedcolumns.finalize(result) + end +end + +function commands.mixflushrest() + if result then + context(mixedcolumns.getrest(result)) + end +end + +function commands.mixflushlist() + if result then + context(mixedcolumns.getlist(result)) + end +end + +function commands.mixstate() + context(result and result.rest and 1 or 0) +end + +function commands.mixcleanup() + if result then + mixedcolumns.cleanup(result) + result = nil + end +end |