if not modules then modules = { } end modules ['node-bck'] = {
version = 1.001,
comment = "companion to node-bck.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
-- beware, this one takes quite some runtime, so we need a status flag
-- maybe some page related state
-- todo: done (or just get rid of done altogether) ... saves no purpose
-- any longer
local attributes, nodes, node = attributes, nodes, node
local enableaction = nodes.tasks.enableaction
local nodecodes = nodes.nodecodes
local listcodes = nodes.listcodes
local hlist_code = nodecodes.hlist
local vlist_code = nodecodes.vlist
local alignmentlist_code = listcodes.alignment
local celllist_code = listcodes.cell
local nuts = nodes.nuts
local nodepool = nuts.pool
local getnext = nuts.getnext
local getprev = nuts.getprev
local getid = nuts.getid
local getlist = nuts.getlist
local getattr = nuts.getattr
local getsubtype = nuts.getsubtype
local getwhd = nuts.getwhd
local getwidth = nuts.getwidth
local getprop = nuts.getprop
local setattr = nuts.setattr
local setlink = nuts.setlink
local setlist = nuts.setlist
local setattributelist = nuts.setattributelist
local setprop = nuts.setprop
local takebox = nuts.takebox
local findtail = nuts.tail
local nextnode = nuts.traversers.node
local nexthlist = nuts.traversers.hlist
local nextlist = nuts.traversers.list
local flush_node_list = nuts.flush_list
local new_rule = nodepool.rule
local new_kern = nodepool.kern
local new_hlist = nodepool.hlist
local privateattributes = attributes.private
local unsetvalue = attributes.unsetvalue
local linefillers = nodes.linefillers
local a_color = privateattributes("color")
local a_transparency = privateattributes("transparency")
local a_colormodel = privateattributes("colormodel")
local a_background = privateattributes("background")
local a_alignbackground = privateattributes("alignbackground")
local a_linefiller = privateattributes("linefiller")
local a_ruled = privateattributes("ruled")
local trace_alignment = false
local report_alignment = logs.reporter("backgrounds","alignment")
trackers.register("backgrounds.alignments",function(v) trace_alignment = v end)
-- We can't use listbuilders with where=alignment because at that stage we have
-- unset boxes. Also, post_linebreak is unsuitable for nested processing as we
-- get the same stuff many times (wrapped again and again).
--
-- After many experiments with different callbacks the shipout is still the best
-- place but then we need to store some settings longer or save them with the node.
-- For color only we can get away with it with an extra attribute flagging a row
-- but for more complex stuff we can better do as we do here now.
local overshoot = math.floor(65781/5) -- could be an option per table (just also store it)
local function colored_a(current,list,template,id)
local width, height, depth = getwhd(current)
local total = height + depth
if width > 0 and total > 0 then
local rule = nil
--
local a = getattr(template,a_linefiller)
if a then
local d = linefillers.data[a%1000]
if d then
rule = linefillers.filler(template,d,width,height,depth)
end
end
--
if not rule then
rule = new_rule(width,height,depth)
end
setattributelist(rule,template)
local back = new_kern(-((id == vlist_code and total) or width))
return setlink(rule,back,list)
end
end
local function colored_b(current,list,template,id,indent)
local width, height, depth = getwhd(current)
local total = height + depth
if width > 0 and total > 0 then
local fore = (indent ~= 0) and new_kern(indent)
local rule = nil
--
local a = getattr(template,a_linefiller)
if a then
local d = linefillers.data[a%1000]
if d then
rule = linefillers.filler(template,d,width-indent,height,depth)
end
end
--
if not rule then
rule = new_rule(width-indent,height+overshoot,depth+overshoot)
setattributelist(rule,template)
end
if overshoot == 0 then
local back = new_kern(-((id == vlist_code and total) or width))
return setlink(fore,rule,back,list)
else
rule = new_hlist(rule)
return setlink(fore,rule,list)
end
end
end
local templates = { }
local currentrow = 0
local enabled = false
local alignments = false
local function add_alignbackgrounds(head,list)
for current, id, subtype, list in nextlist, list do
if list and id == hlist_code and subtype == celllist_code then
for template in nexthlist, list do
local background = getattr(template,a_alignbackground)
if background then
local list = colored_a(current,list,template)
if list then
setlist(current,list)
end
setattr(template,a_alignbackground,unsetvalue) -- or property
end
break
end
end
end
local template = getprop(head,"alignmentchecked")
if template then
list = colored_b(head,list,template[1],hlist_code,template[2])
flush_node_list(template)
templates[currentrow] = false
return list
end
end
local function add_backgrounds(head,id,list)
if list then
for current, id, subtype, list in nextlist, list do
if list then
if alignments and subtype == alignmentlist_code then
local l = add_alignbackgrounds(current,list)
if l then
list = l
setlist(current,list)
end
end
local l = add_backgrounds(current,id,list)
if l then
list = l
setlist(current,l)
end
end
end
end
if id == hlist_code or id == vlist_code then
local background = getattr(head,a_background)
if background then
list = colored_a(head,list,head,id)
-- not needed
setattr(head,a_background,unsetvalue) -- or property
return list
end
end
end
function nodes.handlers.backgrounds(head)
add_backgrounds(head,getid(head),getlist(head))
return head
end
function nodes.handlers.backgroundspage(head,where)
if head and where == "alignment" then
for n in nexthlist, head do
local p = getprop(n,"alignmentchecked")
if not p and getsubtype(n) == alignmentlist_code then
currentrow = currentrow + 1
local template = templates[currentrow]
if trace_alignment then
report_alignment("%03i %s %s",currentrow,"page",template and "+" or "-")
end
setprop(n,"alignmentchecked",template)
end
end
end
return head
end
function nodes.handlers.backgroundsvbox(head,where)
if head and where == "vbox" then
local list = getlist(head)
if list then
for n in nexthlist, list do
local p = getprop(n,"alignmentchecked")
if not p and getsubtype(n) == alignmentlist_code then
currentrow = currentrow + 1
local template = templates[currentrow]
if trace_alignment then
report_alignment("%03i %s %s",currentrow,"vbox",template and "+" or "-")
end
setprop(n,"alignmentchecked",template)
end
end
end
end
return head
end
-- interfaces.implement {
-- name = "enablebackgroundboxes",
-- onlyonce = true,
-- actions = enableaction,
-- arguments = { "'shipouts'", "'nodes.handlers.backgrounds'" }
-- }
--
-- doing it in the shipout works as well but this is nicer
local function enable(alignmentstoo)
if not enabled then
enabled = true
enableaction("shipouts","nodes.handlers.backgrounds")
end
if not alignments and alignmentstoo then
alignments = true
enableaction("vboxbuilders","nodes.handlers.backgroundsvbox")
enableaction("mvlbuilders", "nodes.handlers.backgroundspage")
end
end
interfaces.implement {
name = "enablebackgroundboxes",
onlyonce = true,
actions = enable,
}
interfaces.implement {
name = "enablebackgroundalign",
onlyonce = true,
actions = function()
enable(true)
end,
}
interfaces.implement {
name = "setbackgroundrowdata",
arguments = { "integer", "integer", "dimension" },
actions = function(row,box,indent)
row = row -1 -- better here than in tex
if box == 0 then
templates[row] = false
else
templates[row] = { takebox(box), indent }
end
end,
}
interfaces.implement {
name = "resetbackgroundrowdata",
actions = function()
currentrow = 0
end,
}
