2016-01-12 16:26:00

1 files changed, 309 insertions, 0 deletions

diff --git a/tex/context/base/mkiv/typo-fln.lua b/tex/context/base/mkiv/typo-fln.lua
new file mode 100644
index 000000000..1e1a2c44a
--- /dev/null
+++ b/tex/context/base/mkiv/typo-fln.lua
@@ -0,0 +1,309 @@
+if not modules then modules = { } end modules ['typo-fln'] = {
+    version   = 1.001,
+    comment   = "companion to typo-fln.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- When I ran into the following experimental code again, I figured that it dated
+-- from the early days of mkiv, so I updates it a bit to fit into todays context.
+-- In the process I might have messed up things. For instance we had a diffent
+-- wrapper then using head and tail.
+
+-- todo: only letters (no punctuation)
+-- todo: nuts
+
+local trace_firstlines   = false  trackers.register("typesetters.firstlines", function(v) trace_firstlines = v end)
+local report_firstlines  = logs.reporter("nodes","firstlines")
+
+typesetters.firstlines   = typesetters.firstlines or { }
+local firstlines         = typesetters.firstlines
+
+local nodes              = nodes
+local tasks              = nodes.tasks
+
+local context            = context
+local implement          = interfaces.implement
+
+local nuts               = nodes.nuts
+local tonut              = nuts.tonut
+local tonode             = nuts.tonode
+
+local getnext            = nuts.getnext
+local getid              = nuts.getid
+local getfield           = nuts.getfield
+local setfield           = nuts.setfield
+local getlist            = nuts.getlist
+local setlist            = nuts.setlist
+local getattr            = nuts.getattr
+local setattr            = nuts.setattr
+local getbox             = nuts.getbox
+
+local nodecodes          = nodes.nodecodes
+local glyph_code         = nodecodes.glyph
+local disc_code          = nodecodes.disc
+local kern_code          = nodecodes.kern
+
+local traverse_id        = nuts.traverse_id
+local free_node_list     = nuts.flush_list
+local free_node          = nuts.flush_node
+local copy_node_list     = nuts.copy_list
+local insert_node_after  = nuts.insert_after
+local insert_node_before = nuts.insert_before
+local hpack_node_list    = nuts.hpack
+local remove_node        = nuts.remove
+
+local nodepool           = nuts.pool
+local newpenalty         = nodepool.penalty
+local newkern            = nodepool.kern
+local tracerrule         = nodes.tracers.pool.nuts.rule
+
+local actions            = { }
+firstlines.actions       = actions
+
+local a_firstline        = attributes.private('firstline')
+local a_color            = attributes.private('color')
+local a_transparency     = attributes.private('transparency')
+local a_colorspace       = attributes.private('colormodel')
+
+local texsetattribute    = tex.setattribute
+local unsetvalue         = attributes.unsetvalue
+
+local variables          = interfaces.variables
+local v_default          = variables.default
+local v_line             = variables.line
+local v_word             = variables.word
+
+----- is_letter          = characters.is_letter
+----- categories         = characters.categories
+
+local settings           = nil
+
+function firstlines.set(specification)
+    settings = specification or { }
+    tasks.enableaction("processors","typesetters.firstlines.handler")
+    if trace_firstlines then
+        report_firstlines("enabling firstlines")
+    end
+    texsetattribute(a_firstline,1)
+end
+
+implement {
+    name      = "setfirstline",
+    actions   = firstlines.set,
+    arguments = {
+        {
+            { "alternative" },
+            { "font", "integer" },
+            { "dynamic", "integer" },
+            { "ma", "integer" },
+            { "ca", "integer" },
+            { "ta", "integer" },
+            { "n", "integer" },
+        }
+    }
+}
+
+actions[v_line] = function(head,setting)
+ -- local attribute = fonts.specifiers.contextnumber(setting.feature) -- was experimental
+    local dynamic    = setting.dynamic
+    local font       = setting.font
+    local noflines   = setting.n or 1
+    local ma         = setting.ma or 0
+    local ca         = setting.ca
+    local ta         = setting.ta
+    local hangafter  = tex.hangafter
+    local hangindent = tex.hangindent
+    local parindent  = tex.parindent
+    local nofchars   = 0
+    local n          = 0
+    local temp       = copy_node_list(head)
+    local linebreaks = { }
+    for g in traverse_id(glyph_code,temp) do
+        if dynamic > 0 then
+            setattr(g,0,dynamic)
+        end
+        setfield(g,"font",font)
+    end
+    local start = temp
+    local list  = temp
+    local prev  = temp
+    for i=1,noflines do
+        local hsize = tex.hsize - tex.leftskip.width - tex.rightskip.width
+        if i == 1 then
+            hsize = hsize - parindent
+        end
+        if i <= - hangafter then
+            hsize = hsize - hangindent
+        end
+        while start do
+            local id = getid(start)
+            if id == glyph_code then
+                n = n + 1
+            elseif id == disc_code then
+                -- this could be an option
+            elseif id == kern_code then -- todo: fontkern
+                -- this could be an option
+            elseif n > 0 then
+                local pack = hpack_node_list(copy_node_list(list,start))
+                if getfield(pack,"width") > hsize then
+                    free_node_list(pack)
+                    list = prev
+                    break
+                else
+                    linebreaks[i] = n
+                    prev = start
+                    free_node_list(pack)
+                    nofchars = n
+                end
+            end
+            start = getnext(start)
+        end
+        if not linebreaks[i] then
+            linebreaks[i] = n
+        end
+    end
+    local start = head
+    local n     = 0
+    for i=1,noflines do
+        local linebreak = linebreaks[i]
+        while start and n < nofchars do
+            local id = getid(start)
+            if id == glyph_code then -- or id == disc_code then
+                if dynamic > 0 then
+                    setattr(start,0,dynamic)
+                end
+                setfield(start,"font",font)
+                if ca and ca > 0 then
+                    setattr(start,a_colorspace,ma == 0 and 1 or ma)
+                    setattr(start,a_color,ca)
+                end
+                if ta and ta > 0 then
+                    setattr(start,a_transparency,ta)
+                end
+                n = n + 1
+            end
+            if linebreak == n then
+                if trace_firstlines then
+                    head, start = insert_node_after(head,start,newpenalty(10000)) -- nobreak
+                    head, start = insert_node_after(head,start,newkern(-65536))
+                    head, start = insert_node_after(head,start,tracerrule(65536,4*65536,2*65536,"darkblue"))
+                end
+                head, start = insert_node_after(head,start,newpenalty(-10000)) -- break
+                break
+            end
+            start = getnext(start)
+        end
+    end
+    free_node_list(temp)
+    return head, true
+end
+
+actions[v_word] = function(head,setting)
+ -- local attribute = fonts.specifiers.contextnumber(setting.feature) -- was experimental
+    local dynamic  = setting.dynamic
+    local font     = setting.font
+    local words    = 0
+    local nofwords = setting.n or 1
+    local start    = head
+    local ok       = false
+    local ma       = setting.ma or 0
+    local ca       = setting.ca
+    local ta       = setting.ta
+    while start do
+        local id = getid(start)
+        -- todo: delete disc nodes
+        if id == glyph_code then
+            if not ok then
+                words = words + 1
+                ok = true
+            end
+            if ca and ca > 0 then
+                setattr(start,a_colorspace,ma == 0 and 1 or ma)
+                setattr(start,a_color,ca)
+            end
+            if ta and ta > 0 then
+                setattr(start,a_transparency,ta)
+            end
+            if dynamic > 0 then
+                setattr(start,0,dynamic)
+            end
+            setfield(start,"font",font)
+        elseif id == disc_code then
+            -- continue
+        elseif id == kern_code then -- todo: fontkern
+            -- continue
+        else
+            ok = false
+            if words == nofwords then
+                break
+            end
+        end
+        start = getnext(start)
+    end
+    return head, true
+end
+
+actions[v_default] = actions[v_line]
+
+function firstlines.handler(head)
+    head = tonut(head)
+    local start = head
+    local attr  = nil
+    while start do
+        attr = getattr(start,a_firstline)
+        if attr then
+            break
+        elseif getid(start) == glyph_code then
+            break
+        else
+            start = getnext(start)
+        end
+    end
+    if attr then
+        -- here as we can process nested boxes first so we need to keep state
+        tasks.disableaction("processors","typesetters.firstlines.handler")
+     -- texsetattribute(attribute,unsetvalue)
+        local alternative = settings.alternative or v_default
+        local action = actions[alternative] or actions[v_default]
+        if action then
+            if trace_firstlines then
+                report_firstlines("processing firstlines, alternative %a",alternative)
+            end
+            local head, done = action(head,settings)
+            return tonode(head), done
+        end
+    end
+    return tonode(head), false
+end
+
+-- goodie
+
+local function applytofirstcharacter(box,what)
+    local tbox = getbox(box) -- assumes hlist
+    local list = getlist(tbox)
+    local done = nil
+    for n in traverse_id(glyph_code,list) do
+        list = remove_node(list,n)
+        done = n
+        break
+    end
+    if done then
+        setlist(tbox,list)
+        local kind = type(what)
+        if kind == "string" then
+            context[what](tonode(done))
+        elseif kind == "function" then
+            what(done)
+        else
+            -- error
+        end
+    end
+end
+
+implement {
+    name      = "applytofirstcharacter",
+    actions   = applytofirstcharacter,
+    arguments = { "integer", "string" }
+}