beta 2013.08.22 15:28

1 files changed, 284 insertions, 0 deletions

diff --git a/tex/context/base/typo-fln.lua b/tex/context/base/typo-fln.lua
new file mode 100644
index 000000000..322374ac0
--- /dev/null
+++ b/tex/context/base/typo-fln.lua
@@ -0,0 +1,284 @@
+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")
+
+local nodes             = nodes
+local tasks             = nodes.tasks
+
+local nodecodes         = nodes.nodecodes
+local glyph             = nodecodes.glyph
+local rule              = nodecodes.rule
+local disc              = nodecodes.disc
+
+local traverse_id       = nodes.traverse_id
+local free_node_list    = nodes.flush_list
+local copy_node_list    = nodes.copy_list
+local insert_node_after = nodes.insert_after
+local hpack_node_list   = nodes.hpack
+
+local hpack_filter      = nodes.processors.hpack_filter
+
+local newpenalty        = nodes.pool.penalty
+
+typesetters.firstlines  = typesetters.firstlines or { }
+local firstlines        = typesetters.firstlines
+
+local actions           = { }
+firstlines.actions      = actions
+
+local busy              = false
+local settings          = { }
+
+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 unsetvalue        = attributes.unsetvalue
+
+local variables         = interfaces.variables
+
+----- is_letter         = characters.is_letter
+----- categories        = characters.categories
+
+firstlines.actions[variables.line] = function(head,setting)
+ -- local attribute = fonts.specifiers.contextnumber(setting.feature) -- was experimental
+    local dynamic = setting.dynamic
+    local font    = setting.font
+    -- make copy with dynamic feature attribute set
+    local list = copy_node_list(head)
+    for g in traverse_id(glyph,list) do
+        if dynamic > 0 then
+            g[0] = dynamic
+        end
+        g.font = font
+    end
+    local words        = 0
+    local nofchars     = 0
+    local nofwords     = 1
+    local going        = true
+    local lastnofchars = 0
+    local hsize        = tex.hsize - tex.parindent - tex.leftskip.width - tex.rightskip.width -- can be a helper
+    while going do
+        -- (slow) stepwise pass (okay, we could do do a vsplit and stitch but why do difficult)
+        local temp   = copy_node_list(list)
+        local start  = temp
+        local ok     = false
+        lastnofchars = nofchars
+        nofchars     = 0
+        words        = 0
+        local quit   = false
+        while start do
+            -- also nicely quits on dics node
+            local id = start.id
+            if id == glyph then
+             -- if not is_letter[categories[start.char]] then
+             --     quit = true
+             -- elseif not ok then
+                if not ok then
+                    words = words + 1
+                    ok = true
+                end
+                nofchars = nofchars + 1
+            elseif id == disc then
+                -- this could be an option
+            else
+                quit = true
+            end
+            if quit then
+                ok = false
+                if words == nofwords then
+                    local f = start.next
+                    start.next = nil
+                    free_node_list(f)
+                    break
+                end
+                quit = false
+            end
+            start = start.next
+        end
+        if not start then
+            going = false
+        end
+        local pack = hpack_node_list(hpack_filter(temp))
+        if pack.width > hsize then
+            nofchars = lastnofchars
+            break
+        else
+            nofwords = nofwords + 1
+        end
+        free_node_list(pack)
+    end
+    -- set dynamic attribute in real list
+    local start = head
+    local ma    = setting.ma or 0
+    local ca    = setting.ca
+    local ta    = setting.ta
+    while start do
+        local id = start.id
+        if id == glyph then -- or id == disc then
+            if nofchars > 0 then
+                if dynamic > 0 then
+                    start[0] = dynamic
+                end
+                start.font = font
+                if ca and ca > 0 then
+                    start[a_colorspace] = ma == 0 and 1 or ma
+                    start[a_color]      = ca
+                end
+                if ta and ta > 0 then
+                    start[a_transparency] = ta
+                end
+                nofchars = nofchars - 1
+                if nofchars == 0 then
+                    insert_node_after(head,start,newpenalty(-10000)) -- break
+                end
+            else
+                break
+            end
+        end
+        start = start.next
+    end
+    -- variant (no disc nodes)
+ -- if false then
+ --     for g in traverse_id(glyph,head) do
+ --         if nofchars > 0 then
+ --             if dynamic > 0 then
+ --                 g[0] = dynamic
+ --             end
+ --             g.font = font
+ --             nofchars = nofchars - 1
+ --             if nofchars == 0 then
+ --                 insert_node_after(head,g,newpenalty(-10000)) -- break
+ --             end
+ --         end
+ --     end
+ -- end
+    return head, true
+end
+
+firstlines.actions[variables.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 = start.id
+        -- todo: delete disc nodes
+        if id == glyph then
+            if not ok then
+                words = words + 1
+                ok = true
+            end
+            if ca and ca > 0 then
+                start[a_colorspace] = ma == 0 and 1 or ma
+                start[a_color]      = ca
+            end
+            if ta and ta > 0 then
+                start[a_transparency] = ta
+            end
+            if dynamic > 0 then
+                start[0] = dynamic
+            end
+            start.font = font
+        elseif id == disc then
+            -- continue
+        else
+            ok = false
+            if words == nofwords then
+                break
+            end
+        end
+        start = start.next
+    end
+    return head, true
+end
+
+local function process(namespace,attribute,head)
+    if not busy then
+        local start, attr = head, nil
+        while start do
+            attr = start[attribute]
+            if attr or start.id == glyph then
+                break
+            else
+                start = start.next
+            end
+        end
+        if attr then
+            local setting = settings[attr]
+            if setting then
+                local action = actions[setting.alternative]
+                if action then
+                    busy = true
+                    head, done = action(head,setting)
+                    busy = false
+                end
+            end
+            for g in traverse_id(glyph,head) do
+                -- inefficient: we could quit at unset
+                g[attribute] = unsetvalue
+            end
+            return head, true
+        end
+    end
+    return head, false
+end
+
+-- local enabled = false
+
+-- function firstlines.set(n)
+--     if n == variables.reset or not tonumber(n) or n == 0 then
+--         texsetattribute(a_firstline,unsetvalue)
+--     else
+--         if not enabled then
+--             tasks.enableaction("processors","typesetters.firstlines.handler")
+--             if trace_paragraphs then
+--                 report_firstlines("enabling firstlines")
+--             end
+--             enabled = true
+--         end
+--         texsetattribute(a_firstline,n)
+--     end
+-- end
+
+firstlines.attribute = a_firstline
+
+firstlines.handler = nodes.installattributehandler {
+    name      = "firstlines",
+    namespace = firstlines,
+    processor = process,
+}
+
+function firstlines.define(setting)
+    local n = #settings + 1
+    settings[n] = setting
+    tasks.enableaction("processors","typesetters.firstlines.handler")
+    return n
+end
+
+function commands.definefirstline(setting)
+    context(firstlines.define(setting))
+end