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Diffstat (limited to 'tex/context/base/typo-bld.lua')
| -rw-r--r-- | tex/context/base/typo-bld.lua | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/tex/context/base/typo-bld.lua b/tex/context/base/typo-bld.lua new file mode 100644 index 000000000..87d280541 --- /dev/null +++ b/tex/context/base/typo-bld.lua @@ -0,0 +1,186 @@ +if not modules then modules = { } end modules ['typo-bld'] = { -- was node-par + version = 1.001, + comment = "companion to typo-bld.mkiv", + author = "Hans Hagen, PRAGMA-ADE, Hasselt NL", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "see context related readme files" +} + +local insert, remove = table.insert, table.remove + +local builders, nodes, node = builders, nodes, node + +builders.paragraphs = builders.paragraphs or { } +local parbuilders = builders.paragraphs + +parbuilders.constructors = parbuilders.constructors or { } +local constructors = parbuilders.constructors + +constructors.names = constructors.names or { } +local names = constructors.names + +constructors.numbers = constructors.numbers or { } +local numbers = constructors.numbers + +constructors.methods = constructors.methods or { } +local methods = constructors.methods + +local a_parbuilder = attributes.numbers['parbuilder'] or 999 -- why 999 +constructors.attribute = a_parbuilder + +local unsetvalue = attributes.unsetvalue +local texsetattribute = tex.setattribute +local has_attribute = node.has_attribute +local texnest = tex.nest + +local nodepool = nodes.pool +local new_baselineskip = nodepool.baselineskip +local new_lineskip = nodepool.lineskip +local insert_node_before = node.insert_before +local hpack_node = node.hpack + +local starttiming = statistics.starttiming +local stoptiming = statistics.stoptiming + +storage.register("builders/paragraphs/constructors/names", names, "builders.paragraphs.constructors.names") +storage.register("builders/paragraphs/constructors/numbers", numbers, "builders.paragraphs.constructors.numbers") + +local report_parbuilders = logs.reporter("parbuilders") + +local mainconstructor = nil -- not stored in format +local nofconstructors = 0 +local stack = { } + +function constructors.define(name) + nofconstructors = nofconstructors + 1 + names[nofconstructors] = name + numbers[name] = nofconstructors +end + +function constructors.set(name) --- will go + if name then + mainconstructor = numbers[name] or unsetvalue + else + mainconstructor = stack[#stack] or unsetvalue + end + texsetattribute(a_parbuilder,mainconstructor) + if mainconstructor ~= unsetvalue then + constructors.enable() + end +end + +function constructors.start(name) + local number = numbers[name] + insert(stack,number) + mainconstructor = number or unsetvalue + texsetattribute(a_parbuilder,mainconstructor) + if mainconstructor ~= unsetvalue then + constructors.enable() + end +-- report_parbuilders("start %s",name) +end + +function constructors.stop() + remove(stack) + mainconstructor = stack[#stack] or unsetvalue + texsetattribute(a_parbuilder,mainconstructor) + if mainconstructor == unsetvalue then + constructors.disable() + end +-- report_parbuilders("stop") +end + +-- return values: +-- +-- true : tex will break itself +-- false : idem but dangerous +-- head : list of valid vmode nodes with last being hlist + +function constructors.handler(head,followed_by_display) + if type(head) == "boolean" then + return head + else + local attribute = has_attribute(head,a_parbuilder) -- or mainconstructor + if attribute then + local method = names[attribute] + if method then + local handler = methods[method] + if handler then + return handler(head,followed_by_display) + else + report_parbuilders("contructor method '%s' is not defined",tostring(method)) + return true -- let tex break + end + end + end + return true -- let tex break + end +end + +-- just for testing + +function constructors.methods.default(head,followed_by_display) + return true -- let tex break +end + +-- also for testing (now also surrounding spacing done) + +function builders.paragraphs.constructors.methods.oneline(head,followed_by_display) + -- when needed we will turn this into a helper + local t = texnest[texnest.ptr] + local h = hpack_node(head) + local d = tex.baselineskip.width - t.prevdepth - h.height + t.prevdepth = h.depth + t.prevgraf = 1 + if d < tex.lineskiplimit then + return insert_node_before(h,h,new_lineskip(tex.lineskip)) + else + return insert_node_before(h,h,new_baselineskip(d)) + end +end + +-- It makes no sense to have a sequence here as we already have +-- pre and post hooks and only one parbuilder makes sense, so no: +-- +-- local actions = nodes.tasks.actions("parbuilders") +-- +-- yet ... maybe some day. + +local actions = constructors.handler +local enabled = false + +local function processor(head,followed_by_display) + -- todo: not again in otr so we need to flag + if enabled then + starttiming(parbuilders) + local head = actions(head,followed_by_display) + stoptiming(parbuilders) + return head + else + return true -- let tex do the work + end +end + +function constructors.enable() + enabled = true +end + +function constructors.disable() + enabled = false +end + + +callbacks.register('linebreak_filter', processor, "breaking paragraps into lines") + +statistics.register("linebreak processing time", function() + return statistics.elapsedseconds(parbuilders) +end) + +-- interface + +commands.defineparbuilder = constructors.define +commands.startparbuilder = constructors.start +commands.stopparbuilder = constructors.stop +commands.setparbuilder = constructors.set +commands.enableparbuilder = constructors.enable +commands.disableparbuilder = constructors.disable |