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if not modules then modules = { } end modules ['spac-ver'] = {
version = 1.001,
comment = "companion to spac-ver.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
-- we also need to call the spacer for inserts!
-- somehow lists still don't always have proper prev nodes so i need to
-- check all of the luatex code some day .. maybe i should replece the
-- whole mvl handler by lua code .. why not
-- todo: use lua nodes with lua data (>0.79)
-- see ** can go when 0.79
-- needs to be redone, too many calls and tests now ... still within some
-- luatex limitations
-- this code dates from the beginning and is kind of experimental; it
-- will be optimized and improved soon .. it's way too complex now but
-- dates from less possibilities
--
-- the collapser will be redone with user nodes; also, we might get make
-- parskip into an attribute and appy it explicitly thereby getting rid
-- of automated injections; eventually i want to get rid of the currently
-- still needed tex -> lua -> tex > lua chain (needed because we can have
-- expandable settings at the tex end
-- todo: strip baselineskip around display math
local next, type, tonumber = next, type, tonumber
local gmatch, concat = string.gmatch, table.concat
local ceil, floor = math.ceil, math.floor
local lpegmatch = lpeg.match
local unpack = unpack or table.unpack
local allocate = utilities.storage.allocate
local todimen = string.todimen
local formatters = string.formatters
local nodes = nodes
local trackers = trackers
local attributes = attributes
local context = context
local tex = tex
local texlists = tex.lists
local texget = tex.get
local texgetcount = tex.getcount
local texgetdimen = tex.getdimen
local texset = tex.set
local texsetdimen = tex.setdimen
local texsetcount = tex.setcount
local texnest = tex.nest
local texgetbox = tex.getbox
local buildpage = tex.triggerbuildpage
local variables = interfaces.variables
local implement = interfaces.implement
local v_local = variables["local"]
local v_global = variables["global"]
local v_box = variables.box
----- v_page = variables.page -- reserved for future use
local v_split = variables.split
local v_min = variables.min
local v_max = variables.max
local v_none = variables.none
local v_line = variables.line
local v_noheight = variables.noheight
local v_nodepth = variables.nodepth
local v_line = variables.line
local v_halfline = variables.halfline
local v_line_m = "-" .. v_line
local v_halfline_m = "-" .. v_halfline
local v_first = variables.first
local v_last = variables.last
local v_top = variables.top
local v_bottom = variables.bottom
local v_minheight = variables.minheight
local v_maxheight = variables.maxheight
local v_mindepth = variables.mindepth
local v_maxdepth = variables.maxdepth
local v_offset = variables.offset
local v_strut = variables.strut
local v_hfraction = variables.hfraction
local v_dfraction = variables.dfraction
local v_bfraction = variables.bfraction
local v_tlines = variables.tlines
local v_blines = variables.blines
-- vertical space handler
local trace_vbox_vspacing = false trackers.register("vspacing.vbox", function(v) trace_vbox_vspacing = v end)
local trace_page_vspacing = false trackers.register("vspacing.page", function(v) trace_page_vspacing = v end)
local trace_page_builder = false trackers.register("builders.page", function(v) trace_page_builder = v end)
local trace_collect_vspacing = false trackers.register("vspacing.collect", function(v) trace_collect_vspacing = v end)
local trace_vspacing = false trackers.register("vspacing.spacing", function(v) trace_vspacing = v end)
local trace_vsnapping = false trackers.register("vspacing.snapping", function(v) trace_vsnapping = v end)
local trace_specials = false trackers.register("vspacing.specials", function(v) trace_specials = v end)
local remove_math_skips = true directives.register("vspacing.removemathskips", function(v) remnove_math_skips = v end)
local report_vspacing = logs.reporter("vspacing","spacing")
local report_collapser = logs.reporter("vspacing","collapsing")
local report_snapper = logs.reporter("vspacing","snapping")
local report_specials = logs.reporter("vspacing","specials")
local a_skipcategory = attributes.private('skipcategory')
local a_skippenalty = attributes.private('skippenalty')
local a_skiporder = attributes.private('skiporder')
local a_snapmethod = attributes.private('snapmethod')
local a_snapvbox = attributes.private('snapvbox')
local nuts = nodes.nuts
local tonut = nuts.tonut
local tonode = nuts.tonode
local getnext = nuts.getnext
local setlink = nuts.setlink
local getprev = nuts.getprev
local getid = nuts.getid
local getlist = nuts.getlist
local setlist = nuts.setlist
local getattr = nuts.getattr
local setattr = nuts.setattr
local getsubtype = nuts.getsubtype
local getbox = nuts.getbox
local getwhd = nuts.getwhd
local setwhd = nuts.setwhd
local getprop = nuts.getprop
local setprop = nuts.setprop
local getglue = nuts.getglue
local setglue = nuts.setglue
local getkern = nuts.getkern
local getpenalty = nuts.getpenalty
local setshift = nuts.setshift
local setwidth = nuts.setwidth
local getwidth = nuts.getwidth
local setheight = nuts.setheight
local getheight = nuts.getheight
local setdepth = nuts.setdepth
local getdepth = nuts.getdepth
local find_node_tail = nuts.tail
local flush_node = nuts.flush_node
local insert_node_after = nuts.insert_after
local insert_node_before = nuts.insert_before
local remove_node = nuts.remove
local count_nodes = nuts.countall
local hpack_node = nuts.hpack
local vpack_node = nuts.vpack
local nextnode = nuts.traversers.node
local nexthlist = nuts.traversers.hlist
local nodereference = nuts.reference
local theprop = nuts.theprop
local listtoutf = nodes.listtoutf
local nodeidstostring = nodes.idstostring
local nodepool = nuts.pool
local new_penalty = nodepool.penalty
local new_kern = nodepool.kern
local new_rule = nodepool.rule
local nodecodes = nodes.nodecodes
local gluecodes = nodes.gluecodes
----- penaltycodes = nodes.penaltycodes
----- listcodes = nodes.listcodes
local penalty_code = nodecodes.penalty
local kern_code = nodecodes.kern
local glue_code = nodecodes.glue
local insert_code = nodecodes.ins
local hlist_code = nodecodes.hlist
local vlist_code = nodecodes.vlist
local rule_code = nodecodes.rule
local localpar_code = nodecodes.localpar
local userskip_code = gluecodes.userskip
local lineskip_code = gluecodes.lineskip
local baselineskip_code = gluecodes.baselineskip
local parskip_code = gluecodes.parskip
local topskip_code = gluecodes.topskip
local splittopskip_code = gluecodes.splittopskip
local linelist_code = nodes.listcodes.line
local abovedisplayskip_code = gluecodes.abovedisplayskip
local belowdisplayskip_code = gluecodes.belowdisplayskip
local abovedisplayshortskip_code = gluecodes.abovedisplayshortskip
local belowdisplayshortskip_code = gluecodes.belowdisplayshortskip
local properties = nodes.properties.data
local vspacing = builders.vspacing or { }
builders.vspacing = vspacing
local vspacingdata = vspacing.data or { }
vspacing.data = vspacingdata
local snapmethods = vspacingdata.snapmethods or { }
vspacingdata.snapmethods = snapmethods
storage.register("builders/vspacing/data/snapmethods", snapmethods, "builders.vspacing.data.snapmethods")
do
local default = {
[v_maxheight] = true,
[v_maxdepth] = true,
[v_strut] = true,
[v_hfraction] = 1,
[v_dfraction] = 1,
[v_bfraction] = 0.25,
}
local fractions = {
[v_minheight] = v_hfraction, [v_maxheight] = v_hfraction,
[v_mindepth] = v_dfraction, [v_maxdepth] = v_dfraction,
[v_box] = v_bfraction,
[v_top] = v_tlines, [v_bottom] = v_blines,
}
local values = {
offset = "offset"
}
local colonsplitter = lpeg.splitat(":")
local function listtohash(str)
local t = { }
for s in gmatch(str,"[^, ]+") do
local key, detail = lpegmatch(colonsplitter,s)
local v = variables[key]
if v then
t[v] = true
if detail then
local k = fractions[key]
if k then
detail = tonumber("0" .. detail)
if detail then
t[k] = detail
end
else
k = values[key]
if k then
detail = todimen(detail)
if detail then
t[k] = detail
end
end
end
end
else
detail = tonumber("0" .. key)
if detail then
t[v_hfraction] = detail
t[v_dfraction] = detail
end
end
end
if next(t) then
t[v_hfraction] = t[v_hfraction] or 1
t[v_dfraction] = t[v_dfraction] or 1
return t
else
return default
end
end
function vspacing.definesnapmethod(name,method)
local n = #snapmethods + 1
local t = listtohash(method)
snapmethods[n] = t
t.name = name -- not interfaced
t.specification = method -- not interfaced
context(n)
end
end
local function validvbox(parentid,list)
if parentid == hlist_code then
local id = getid(list)
if id == localpar_code and getsubtype(list) == 0 then
list = getnext(list)
if not next then
return nil
end
end
local done = nil
for n, id in nextnode, list do
if id == vlist_code or id == hlist_code then
if done then
return nil
else
done = n
end
elseif id == glue_code or id == penalty_code then
-- go on
else
return nil -- whatever
end
end
if done then
local id = getid(done)
if id == hlist_code then
return validvbox(id,getlist(done))
end
end
return done -- only one vbox
end
end
-- we can use a property
local function already_done(parentid,list,a_snapmethod) -- todo: done when only boxes and all snapped
-- problem: any snapped vbox ends up in a line
if list and parentid == hlist_code then
local id = getid(list)
if id == localpar_code and getsubtype(list) == 0 then
list = getnext(list)
if not list then
return false
end
end
for n, id in nextnode, list do
if id == hlist_code or id == vlist_code then
-- local a = getattr(n,a_snapmethod)
-- if not a then
-- -- return true -- not snapped at all
-- elseif a == 0 then
-- return true -- already snapped
-- end
local p = getprop(n,"snapper")
if p then
return p
end
elseif id == glue_code or id == penalty_code then -- or id == kern_code then
-- go on
else
return false -- whatever
end
end
end
return false
end
-- quite tricky: ceil(-something) => -0
local function ceiled(n)
if n < 0 or n < 0.01 then
return 0
else
return ceil(n)
end
end
local function floored(n)
if n < 0 or n < 0.01 then
return 0
else
return floor(n)
end
end
-- check variables.none etc
local function fixedprofile(current)
local profiling = builders.profiling
return profiling and profiling.fixedprofile(current)
end
-- local function onlyoneentry(t)
-- local n = 1
-- for k, v in next, t do
-- if n > 1 then
-- return false
-- end
-- n = n + 1
-- end
-- return true
-- end
local function snap_hlist(where,current,method,height,depth) -- method[v_strut] is default
if fixedprofile(current) then
return
end
local list = getlist(current)
local t = trace_vsnapping and { }
if t then
t[#t+1] = formatters["list content: %s"](listtoutf(list))
t[#t+1] = formatters["snap method: %s"](method.name) -- not interfaced
t[#t+1] = formatters["specification: %s"](method.specification) -- not interfaced
end
local snapht, snapdp
if method[v_local] then
-- snapping is done immediately here
snapht = texgetdimen("bodyfontstrutheight")
snapdp = texgetdimen("bodyfontstrutdepth")
if t then
t[#t+1] = formatters["local: snapht %p snapdp %p"](snapht,snapdp)
end
elseif method[v_global] then
snapht = texgetdimen("globalbodyfontstrutheight")
snapdp = texgetdimen("globalbodyfontstrutdepth")
if t then
t[#t+1] = formatters["global: snapht %p snapdp %p"](snapht,snapdp)
end
else
-- maybe autolocal
-- snapping might happen later in the otr
snapht = texgetdimen("globalbodyfontstrutheight")
snapdp = texgetdimen("globalbodyfontstrutdepth")
local lsnapht = texgetdimen("bodyfontstrutheight")
local lsnapdp = texgetdimen("bodyfontstrutdepth")
if snapht ~= lsnapht and snapdp ~= lsnapdp then
snapht, snapdp = lsnapht, lsnapdp
end
if t then
t[#t+1] = formatters["auto: snapht %p snapdp %p"](snapht,snapdp)
end
end
local wd, ht, dp = getwhd(current)
local h = (method[v_noheight] and 0) or height or ht
local d = (method[v_nodepth] and 0) or depth or dp
local hr = method[v_hfraction] or 1
local dr = method[v_dfraction] or 1
local br = method[v_bfraction] or 0
local ch = h
local cd = d
local tlines = method[v_tlines] or 1
local blines = method[v_blines] or 1
local done = false
local plusht = snapht
local plusdp = snapdp
local snaphtdp = snapht + snapdp
local extra = 0
if t then
t[#t+1] = formatters["hlist: wd %p ht %p (used %p) dp %p (used %p)"](wd,ht,h,dp,d)
t[#t+1] = formatters["fractions: hfraction %s dfraction %s bfraction %s tlines %s blines %s"](hr,dr,br,tlines,blines)
end
if method[v_box] then
local br = 1 - br
if br < 0 then
br = 0
elseif br > 1 then
br = 1
end
local n = ceiled((h+d-br*snapht-br*snapdp)/snaphtdp)
local x = n * snaphtdp - h - d
plusht = h + x / 2
plusdp = d + x / 2
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_box,plusht,plusdp)
end
elseif method[v_max] then
local n = ceiled((h+d)/snaphtdp)
local x = n * snaphtdp - h - d
plusht = h + x / 2
plusdp = d + x / 2
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_max,plusht,plusdp)
end
elseif method[v_min] then
-- we catch a lone min
if method.specification ~= v_min then
local n = floored((h+d)/snaphtdp)
local x = n * snaphtdp - h - d
plusht = h + x / 2
plusdp = d + x / 2
if plusht < 0 then
plusht = 0
end
if plusdp < 0 then
plusdp = 0
end
end
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_min,plusht,plusdp)
end
elseif method[v_none] then
plusht, plusdp = 0, 0
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_none,0,0)
end
end
-- for now, we actually need to tag a box and then check at several points if something ended up
-- at the top of a page
if method[v_halfline] then -- extra halfline
extra = snaphtdp/2
plusht = plusht + extra
plusdp = plusdp + extra
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_halfline,plusht,plusdp)
end
end
if method[v_line] then -- extra line
extra = snaphtdp
plusht = plusht + extra
plusdp = plusdp + extra
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_line,plusht,plusdp)
end
end
if method[v_halfline_m] then -- extra halfline
extra = - snaphtdp/2
plusht = plusht + extra
plusdp = plusdp + extra
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_halfline_m,plusht,plusdp)
end
end
if method[v_line_m] then -- extra line
extra = - snaphtdp
plusht = plusht + extra
plusdp = plusdp + extra
if t then
t[#t+1] = formatters["%s: plusht %p plusdp %p"](v_line_m,plusht,plusdp)
end
end
if method[v_first] then
local thebox = current
local id = getid(thebox)
if id == hlist_code then
thebox = validvbox(id,getlist(thebox))
id = thebox and getid(thebox)
end
if thebox and id == vlist_code then
local list = getlist(thebox)
local lw, lh, ld
for n in nexthlist, list do
lw, lh, ld = getwhd(n)
break
end
if lh then
local wd, ht, dp = getwhd(thebox)
if t then
t[#t+1] = formatters["first line: height %p depth %p"](lh,ld)
t[#t+1] = formatters["dimensions: height %p depth %p"](ht,dp)
end
local delta = h - lh
ch, cd = lh, delta + d
h, d = ch, cd
local shifted = hpack_node(getlist(current))
setshift(shifted,delta)
setlist(current,shifted)
done = true
if t then
t[#t+1] = formatters["first: height %p depth %p shift %p"](ch,cd,delta)
end
elseif t then
t[#t+1] = "first: not done, no content"
end
elseif t then
t[#t+1] = "first: not done, no vbox"
end
elseif method[v_last] then
local thebox = current
local id = getid(thebox)
if id == hlist_code then
thebox = validvbox(id,getlist(thebox))
id = thebox and getid(thebox)
end
if thebox and id == vlist_code then
local list = getlist(thebox)
local lw, lh, ld
for n in nexthlist, list do
lw, lh, ld = getwhd(n)
end
if lh then
local wd, ht, dp = getwhd(thebox)
if t then
t[#t+1] = formatters["last line: height %p depth %p" ](lh,ld)
t[#t+1] = formatters["dimensions: height %p depth %p"](ht,dp)
end
local delta = d - ld
cd, ch = ld, delta + h
h, d = ch, cd
local shifted = hpack_node(getlist(current))
setshift(shifted,delta)
setlist(current,shifted)
done = true
if t then
t[#t+1] = formatters["last: height %p depth %p shift %p"](ch,cd,delta)
end
elseif t then
t[#t+1] = "last: not done, no content"
end
elseif t then
t[#t+1] = "last: not done, no vbox"
end
end
if method[v_minheight] then
ch = floored((h-hr*snapht)/snaphtdp)*snaphtdp + plusht
if t then
t[#t+1] = formatters["minheight: %p"](ch)
end
elseif method[v_maxheight] then
ch = ceiled((h-hr*snapht)/snaphtdp)*snaphtdp + plusht
if t then
t[#t+1] = formatters["maxheight: %p"](ch)
end
else
ch = plusht
if t then
t[#t+1] = formatters["set height: %p"](ch)
end
end
if method[v_mindepth] then
cd = floored((d-dr*snapdp)/snaphtdp)*snaphtdp + plusdp
if t then
t[#t+1] = formatters["mindepth: %p"](cd)
end
elseif method[v_maxdepth] then
cd = ceiled((d-dr*snapdp)/snaphtdp)*snaphtdp + plusdp
if t then
t[#t+1] = formatters["maxdepth: %p"](cd)
end
else
cd = plusdp
if t then
t[#t+1] = formatters["set depth: %p"](cd)
end
end
if method[v_top] then
ch = ch + tlines * snaphtdp
if t then
t[#t+1] = formatters["top height: %p"](ch)
end
end
if method[v_bottom] then
cd = cd + blines * snaphtdp
if t then
t[#t+1] = formatters["bottom depth: %p"](cd)
end
end
local offset = method[v_offset]
if offset then
-- we need to set the attr
if t then
local wd, ht, dp = getwhd(current)
t[#t+1] = formatters["before offset: %p (width %p height %p depth %p)"](offset,wd,ht,dp)
end
local shifted = hpack_node(getlist(current))
setshift(shifted,offset)
setlist(current,shifted)
if t then
local wd, ht, dp = getwhd(current)
t[#t+1] = formatters["after offset: %p (width %p height %p depth %p)"](offset,wd,ht,dp)
end
setattr(shifted,a_snapmethod,0)
setattr(current,a_snapmethod,0)
end
if not height then
setheight(current,ch)
if t then
t[#t+1] = formatters["forced height: %p"](ch)
end
end
if not depth then
setdepth(current,cd)
if t then
t[#t+1] = formatters["forced depth: %p"](cd)
end
end
local lines = (ch+cd)/snaphtdp
if t then
local original = (h+d)/snaphtdp
local whatever = (ch+cd)/(texgetdimen("globalbodyfontstrutheight") + texgetdimen("globalbodyfontstrutdepth"))
t[#t+1] = formatters["final lines : %p -> %p (%p)"](original,lines,whatever)
t[#t+1] = formatters["final height: %p -> %p"](h,ch)
t[#t+1] = formatters["final depth : %p -> %p"](d,cd)
end
-- todo:
--
-- if h < 0 or d < 0 then
-- h = 0
-- d = 0
-- end
if t then
report_snapper("trace: %s type %s\n\t%\n\tt",where,nodecodes[getid(current)],t)
end
if not method[v_split] then
-- so extra will not be compensated at the top of a page
extra = 0
end
return h, d, ch, cd, lines, extra
end
local function snap_topskip(current,method)
local w = getwidth(current)
setwidth(current,0)
return w, 0
end
local categories = {
[0] = "discard",
[1] = "largest",
[2] = "force",
[3] = "penalty",
[4] = "add",
[5] = "disable",
[6] = "nowhite",
[7] = "goback",
[8] = "packed",
[9] = "overlay",
[10] = "enable",
[11] = "notopskip",
}
categories = allocate(table.swapped(categories,categories))
vspacing.categories = categories
function vspacing.tocategories(str)
local t = { }
for s in gmatch(str,"[^, ]") do -- use lpeg instead
local n = tonumber(s)
if n then
t[categories[n]] = true
else
t[b] = true
end
end
return t
end
function vspacing.tocategory(str) -- can be optimized
if type(str) == "string" then
return set.tonumber(vspacing.tocategories(str))
else
return set.tonumber({ [categories[str]] = true })
end
end
vspacingdata.map = vspacingdata.map or { } -- allocate ?
vspacingdata.skip = vspacingdata.skip or { } -- allocate ?
storage.register("builders/vspacing/data/map", vspacingdata.map, "builders.vspacing.data.map")
storage.register("builders/vspacing/data/skip", vspacingdata.skip, "builders.vspacing.data.skip")
do -- todo: interface.variables and properties
local P, C, R, S, Cc, Cs = lpeg.P, lpeg.C, lpeg.R, lpeg.S, lpeg.Cc, lpeg.Cs
vspacing.fixed = false
local map = vspacingdata.map
local skip = vspacingdata.skip
local sign = S("+-")^0
local multiplier = C(sign * R("09")^1) * P("*")
local singlefier = Cs(sign * Cc(1))
local separator = S(", ")
local category = P(":") * C((1-separator)^1)
local keyword = C((1-category-separator)^1)
local splitter = (multiplier + Cc(1)) * keyword * (category + Cc(false))
local k_fixed = variables.fixed
local k_flexible = variables.flexible
local k_category = "category"
local k_penalty = "penalty"
local k_order = "order"
-- This will change: just node.write and we can store the values in skips which
-- then obeys grouping .. but .. we miss the amounts then as they live at the tex
-- end so we then also need to change that bit ... it would be interesting if we
-- could store in properties
local ctx_fixedblankskip = context.fixedblankskip
local ctx_flexibleblankskip = context.flexibleblankskip
local ctx_setblankcategory = context.setblankcategory
local ctx_setblankorder = context.setblankorder
local ctx_setblankpenalty = context.setblankpenalty
----- ctx_setblankhandling = context.setblankhandling
local ctx_flushblankhandling = context.flushblankhandling
local ctx_addpredefinedblankskip = context.addpredefinedblankskip
local ctx_addaskedblankskip = context.addaskedblankskip
local ctx_setblankpacked = context.setblankpacked
local ctx_pushlogger = context.pushlogger
local ctx_startblankhandling = context.startblankhandling
local ctx_stopblankhandling = context.stopblankhandling
local ctx_poplogger = context.poplogger
local pattern = nil
local packed = categories.packed
local function handler(amount, keyword, detail)
if not keyword then
report_vspacing("unknown directive %a",s)
else
local mk = map[keyword]
if mk then
lpegmatch(pattern,mk)
elseif keyword == k_fixed then
ctx_fixedblankskip()
elseif keyword == k_flexible then
ctx_flexibleblankskip()
elseif keyword == k_category then
local category = tonumber(detail)
if category == packed then
ctx_setblankpacked()
elseif category then
ctx_setblankcategory(category)
ctx_flushblankhandling()
end
elseif keyword == k_order and detail then
local order = tonumber(detail)
if order then
ctx_setblankorder(order)
end
elseif keyword == k_penalty and detail then
local penalty = tonumber(detail)
if penalty then
ctx_setblankpenalty(penalty)
end
else
amount = tonumber(amount) or 1
local sk = skip[keyword]
if sk then
ctx_addpredefinedblankskip(amount,keyword)
else -- no check
ctx_addaskedblankskip(amount,keyword)
end
end
end
end
local splitter = ((multiplier + singlefier) * keyword * (category + Cc(false))) / handler
pattern = (splitter + separator^1)^0
function vspacing.analyze(str)
if trace_vspacing then
ctx_pushlogger(report_vspacing)
ctx_startblankhandling()
lpegmatch(pattern,str)
ctx_stopblankhandling()
ctx_poplogger()
else
ctx_startblankhandling()
lpegmatch(pattern,str)
ctx_stopblankhandling()
end
end
--
function vspacing.setmap(from,to)
map[from] = to
end
function vspacing.setskip(key,value,grid)
if value ~= "" then
if grid == "" then grid = value end
skip[key] = { value, grid }
end
end
end
-- implementation
local trace_list, tracing_info, before, after = { }, false, "", ""
local function nodes_to_string(head)
local current = head
local t = { }
while current do
local id = getid(current)
local ty = nodecodes[id]
if id == penalty_code then
t[#t+1] = formatters["%s:%s"](ty,getpenalty(current))
elseif id == glue_code then
t[#t+1] = formatters["%s:%s:%p"](ty,gluecodes[getsubtype(current)],getwidth(current))
elseif id == kern_code then
t[#t+1] = formatters["%s:%p"](ty,getkern(current))
else
t[#t+1] = ty
end
current = getnext(current)
end
return concat(t," + ")
end
local function reset_tracing(head)
trace_list, tracing_info, before, after = { }, false, nodes_to_string(head), ""
end
local function trace_skip(str,sc,so,sp,data)
trace_list[#trace_list+1] = { "skip", formatters["%s | %p | category %s | order %s | penalty %s"](str, getwidth(data), sc or "-", so or "-", sp or "-") }
tracing_info = true
end
local function trace_natural(str,data)
trace_list[#trace_list+1] = { "skip", formatters["%s | %p"](str, getwidth(data)) }
tracing_info = true
end
local function trace_info(message, where, what)
trace_list[#trace_list+1] = { "info", formatters["%s: %s/%s"](message,where,what) }
end
local function trace_node(what)
local nt = nodecodes[getid(what)]
local tl = trace_list[#trace_list]
if tl and tl[1] == "node" then
trace_list[#trace_list] = { "node", formatters["%s + %s"](tl[2],nt) }
else
trace_list[#trace_list+1] = { "node", nt }
end
end
local function trace_done(str,data)
if getid(data) == penalty_code then
trace_list[#trace_list+1] = { "penalty", formatters["%s | %s"](str,getpenalty(data)) }
else
trace_list[#trace_list+1] = { "glue", formatters["%s | %p"](str,getwidth(data)) }
end
tracing_info = true
end
local function show_tracing(head)
if tracing_info then
after = nodes_to_string(head)
for i=1,#trace_list do
local tag, text = unpack(trace_list[i])
if tag == "info" then
report_collapser(text)
else
report_collapser(" %s: %s",tag,text)
end
end
report_collapser("before: %s",before)
report_collapser("after : %s",after)
end
end
-- alignment box begin_of_par vmode_par hmode_par insert penalty before_display after_display
function vspacing.snapbox(n,how)
local sv = snapmethods[how]
if sv then
local box = getbox(n)
local list = getlist(box)
if list then
local s = getattr(list,a_snapmethod)
if s == 0 then
if trace_vsnapping then
-- report_snapper("box list not snapped, already done")
end
else
local wd, ht, dp = getwhd(box)
if false then -- todo: already_done
-- assume that the box is already snapped
if trace_vsnapping then
report_snapper("box list already snapped at (%p,%p): %s",
ht,dp,listtoutf(list))
end
else
local h, d, ch, cd, lines, extra = snap_hlist("box",box,sv,ht,dp)
setprop(box,"snapper",{
ht = h,
dp = d,
ch = ch,
cd = cd,
extra = extra,
current = current,
})
setwhd(box,wd,ch,cd)
if trace_vsnapping then
report_snapper("box list snapped from (%p,%p) to (%p,%p) using method %a (%s) for %a (%s lines): %s",
h,d,ch,cd,sv.name,sv.specification,"direct",lines,listtoutf(list))
end
setattr(box,a_snapmethod,0) --
setattr(list,a_snapmethod,0) -- yes or no
end
end
end
end
end
-- I need to figure out how to deal with the prevdepth that crosses pages. In fact,
-- prevdepth is often quite interfering (even over a next paragraph) so I need to
-- figure out a trick. Maybe use something other than a rule. If we visualize we'll
-- see the baselineskip in action:
--
-- \blank[force,5*big] { \baselineskip1cm xxxxxxxxx \par } \page
-- \blank[force,5*big] { \baselineskip1cm xxxxxxxxx \par } \page
-- \blank[force,5*big] { \baselineskip5cm xxxxxxxxx \par } \page
-- We can register and copy the rule instead.
do
local w, h, d = 0, 0, 0
----- w, h, d = 100*65536, 65536, 65536
local function forced_skip(head,current,width,where,trace) -- looks old ... we have other tricks now
if head == current then
if getsubtype(head) == baselineskip_code then
width = width - getwidth(head)
end
end
if width == 0 then
-- do nothing
elseif where == "after" then
head, current = insert_node_after(head,current,new_rule(w,h,d))
head, current = insert_node_after(head,current,new_kern(width))
head, current = insert_node_after(head,current,new_rule(w,h,d))
else
local c = current
head, current = insert_node_before(head,current,new_rule(w,h,d))
head, current = insert_node_before(head,current,new_kern(width))
head, current = insert_node_before(head,current,new_rule(w,h,d))
current = c
end
if trace then
report_vspacing("inserting forced skip of %p",width)
end
return head, current
end
-- penalty only works well when before skip
local discard = categories.discard
local largest = categories.largest
local force = categories.force
local penalty = categories.penalty
local add = categories.add
local disable = categories.disable
local nowhite = categories.nowhite
local goback = categories.goback
local packed = categories.packed
local overlay = categories.overlay
local enable = categories.enable
local notopskip = categories.notopskip
-- [whatsits][hlist][glue][glue][penalty]
local special_penalty_min = 32250
local special_penalty_max = 35000
local special_penalty_xxx = 0
-- this is rather messy and complex: we want to make sure that successive
-- header don't break but also make sure that we have at least a decent
-- break when we have succesive ones (often when testing)
-- todo: mark headers as such so that we can recognize them
local specialmethods = { }
local specialmethod = 1
specialmethods[1] = function(pagehead,pagetail,start,penalty)
--
if not pagehead or penalty < special_penalty_min or penalty > special_penalty_max then
return
end
local current = pagetail
--
-- nodes.showsimplelist(pagehead,0)
--
if trace_specials then
report_specials("checking penalty %a",penalty)
end
while current do
local id = getid(current)
if id == penalty_code then
local p = properties[current]
if p then
local p = p.special_penalty
if not p then
if trace_specials then
report_specials(" regular penalty, continue")
end
elseif p == penalty then
if trace_specials then
report_specials(" context penalty %a, same level, overloading",p)
end
return special_penalty_xxx
elseif p > special_penalty_min and p < special_penalty_max then
if penalty < p then
if trace_specials then
report_specials(" context penalty %a, lower level, overloading",p)
end
return special_penalty_xxx
else
if trace_specials then
report_specials(" context penalty %a, higher level, quitting",p)
end
return
end
elseif trace_specials then
report_specials(" context penalty %a, higher level, continue",p)
end
else
local p = getpenalty(current)
if p < 10000 then
-- assume some other mechanism kicks in so we seem to have content
if trace_specials then
report_specials(" regular penalty %a, quitting",p)
end
break
else
if trace_specials then
report_specials(" regular penalty %a, continue",p)
end
end
end
end
current = getprev(current)
end
-- none found, so no reson to be special
if trace_specials then
if pagetail then
report_specials(" context penalty, discarding, nothing special")
else
report_specials(" context penalty, discarding, nothing preceding")
end
end
return special_penalty_xxx
end
-- This will be replaced after 0.80+ when we have a more robust look-back and
-- can look at the bigger picture.
-- todo: look back and when a special is there before a list is seen penalty keep ut
-- we now look back a lot, way too often
-- userskip
-- lineskip
-- baselineskip
-- parskip
-- abovedisplayskip
-- belowdisplayskip
-- abovedisplayshortskip
-- belowdisplayshortskip
-- topskip
-- splittopskip
-- we could inject a vadjust to force a recalculation .. a mess
--
-- So, the next is far from robust and okay but for the moment this overlaying
-- has to do. Always test this with the examples in spac-ver.mkvi!
local function check_experimental_overlay(head,current)
local p = nil
local c = current
local n = nil
local function overlay(p,n,mvl)
local p_wd, p_ht, p_dp = getwhd(p)
local n_wd, n_ht, n_dp = getwhd(n)
local skips = 0
--
-- We deal with this at the tex end .. we don't see spacing .. enabling this code
-- is probably harmless but then we need to test it.
--
-- we could calculate this before we call
--
-- problem: prev list and next list can be unconnected
--
local c = getnext(p)
local l = c
while c and c ~= n do
local id = getid(c)
if id == glue_code then
skips = skips + getwidth(c)
elseif id == kern_code then
skips = skips + getkern(c)
end
l = c
c = getnext(c)
end
local c = getprev(n)
while c and c ~= n and c ~= l do
local id = getid(c)
if id == glue_code then
skips = skips + getwidth(c)
elseif id == kern_code then
skips = skips + getkern(c)
end
c = getprev(c)
end
--
local delta = n_ht + skips + p_dp
texsetdimen("global","d_spac_overlay",-delta) -- for tracing
-- we should adapt pagetotal ! (need a hook for that) .. now we have the wrong pagebreak
local k = new_kern(-delta)
head = insert_node_before(head,n,k)
if n_ht > p_ht then
local k = new_kern(n_ht-p_ht)
head = insert_node_before(head,p,k)
end
if trace_vspacing then
report_vspacing("overlaying, prev height: %p, prev depth: %p, next height: %p, skips: %p, move up: %p",p_ht,p_dp,n_ht,skips,delta)
end
return remove_node(head,current,true)
end
-- goto next line
while c do
local id = getid(c)
if id == glue_code or id == penalty_code or id == kern_code then
-- skip (actually, remove)
c = getnext(c)
elseif id == hlist_code then
n = c
break
else
break
end
end
if n then
-- we have a next line, goto prev line
c = current
while c do
local id = getid(c)
if id == glue_code or id == penalty_code then -- kern ?
c = getprev(c)
elseif id == hlist_code then
p = c
break
else
break
end
end
if not p then
if a_snapmethod == a_snapvbox then
-- quit, we're not on the mvl
else
-- inefficient when we're at the end of a page
local c = tonut(texlists.page_head)
while c and c ~= n do
local id = getid(c)
if id == hlist_code then
p = c
end
c = getnext(c)
end
if p and p ~= n then
return overlay(p,n,true)
end
end
elseif p ~= n then
return overlay(p,n,false)
end
end
-- in fact, we could try again later ... so then no remove (a few tries)
return remove_node(head, current, true)
end
local function collapser(head,where,what,trace,snap,a_snapmethod) -- maybe also pass tail
if trace then
reset_tracing(head)
end
local current = head
local oldhead = head
local glue_order = 0
local glue_data
local force_glue = false
local penalty_order = 0
local penalty_data
local natural_penalty
local special_penalty
local parskip
local ignore_parskip = false
local ignore_following = false
local ignore_whitespace = false
local keep_together = false
local lastsnap
local pagehead
local pagetail
--
-- todo: keep_together: between headers
--
local function getpagelist()
if not pagehead then
pagehead = texlists.page_head
if pagehead then
pagehead = tonut(pagehead)
pagetail = find_node_tail(pagehead) -- no texlists.page_tail yet-- no texlists.page_tail yet
end
end
end
--
local function compensate(n)
local g = 0
while n and getid(n) == glue_code do
g = g + getwidth(n)
n = getnext(n)
end
if n then
local p = getprop(n,"snapper")
if p then
local extra = p.extra
if extra and extra < 0 then -- hm, extra can be unset ... needs checking
local h = p.ch -- getheight(n)
-- maybe an extra check
-- if h - extra < g then
setheight(n,h-2*extra)
p.extra = 0
if trace_vsnapping then
report_snapper("removed extra space at top: %p",extra)
end
-- end
end
end
return n
end
end
--
local function removetopsnap()
getpagelist()
if pagehead then
local n = pagehead and compensate(pagehead)
if n and n ~= pagetail then
local p = getprop(pagetail,"snapper")
if p then
local e = p.extra
if e and e < 0 then
local t = texget("pagetotal")
if t > 0 then
local g = texget("pagegoal") -- 1073741823 is signal
local d = g - t
if d < -e then
local penalty = new_penalty(1000000)
setlink(penalty,head)
head = penalty
report_snapper("force pagebreak due to extra space at bottom: %p",e)
end
end
end
end
end
elseif head then
compensate(head)
end
end
--
local function getavailable()
getpagelist()
if pagehead then
local t = texget("pagetotal")
if t > 0 then
local g = texget("pagegoal")
return g - t
end
end
return false
end
--
local function flush(why)
if penalty_data then
local p = new_penalty(penalty_data)
if trace then
trace_done("flushed due to " .. why,p)
end
if penalty_data >= 10000 then -- or whatever threshold?
local prev = getprev(current)
if getid(prev) == glue_code then -- maybe go back more, or maybe even push back before any glue
-- tricky case: spacing/grid-007.tex: glue penalty glue
head = insert_node_before(head,prev,p)
else
head = insert_node_before(head,current,p)
end
else
head = insert_node_before(head,current,p)
end
-- if penalty_data > special_penalty_min and penalty_data < special_penalty_max then
local props = properties[p]
if props then
props.special_penalty = special_penalty or penalty_data
else
properties[p] = {
special_penalty = special_penalty or penalty_data
}
end
-- end
end
if glue_data then
if force_glue then
if trace then
trace_done("flushed due to forced " .. why,glue_data)
end
head = forced_skip(head,current,getwidth(glue_data,width),"before",trace)
flush_node(glue_data)
else
local width, stretch, shrink = getglue(glue_data)
if width ~= 0 then
if trace then
trace_done("flushed due to non zero " .. why,glue_data)
end
head = insert_node_before(head,current,glue_data)
elseif stretch ~= 0 or shrink ~= 0 then
if trace then
trace_done("flushed due to stretch/shrink in" .. why,glue_data)
end
head = insert_node_before(head,current,glue_data)
else
-- report_vspacing("needs checking (%s): %p",gluecodes[getsubtype(glue_data)],w)
flush_node(glue_data)
end
end
end
if trace then
trace_node(current)
end
glue_order, glue_data, force_glue = 0, nil, false
penalty_order, penalty_data, natural_penalty = 0, nil, nil
parskip, ignore_parskip, ignore_following, ignore_whitespace = nil, false, false, false
end
--
if trace_vsnapping then
report_snapper("global ht/dp = %p/%p, local ht/dp = %p/%p",
texgetdimen("globalbodyfontstrutheight"),
texgetdimen("globalbodyfontstrutdepth"),
texgetdimen("bodyfontstrutheight"),
texgetdimen("bodyfontstrutdepth")
)
end
if trace then
trace_info("start analyzing",where,what)
end
if snap and where == "page" then
removetopsnap()
end
while current do
local id = getid(current)
if id == hlist_code or id == vlist_code then
-- needs checking, why so many calls
if snap then
lastsnap = nil
local list = getlist(current)
local s = getattr(current,a_snapmethod)
if not s then
-- if trace_vsnapping then
-- report_snapper("mvl list not snapped")
-- end
elseif s == 0 then
if trace_vsnapping then
report_snapper("mvl %a not snapped, already done: %s",nodecodes[id],listtoutf(list))
end
else
local sv = snapmethods[s]
if sv then
-- check if already snapped
local done = list and already_done(id,list,a_snapmethod)
if done then
-- assume that the box is already snapped
if trace_vsnapping then
local w, h, d = getwhd(current)
report_snapper("mvl list already snapped at (%p,%p): %s",h,d,listtoutf(list))
end
else
local h, d, ch, cd, lines, extra = snap_hlist("mvl",current,sv,false,false)
lastsnap = {
ht = h,
dp = d,
ch = ch,
cd = cd,
extra = extra,
current = current,
}
setprop(current,"snapper",lastsnap)
if trace_vsnapping then
report_snapper("mvl %a snapped from (%p,%p) to (%p,%p) using method %a (%s) for %a (%s lines): %s",
nodecodes[id],h,d,ch,cd,sv.name,sv.specification,where,lines,listtoutf(list))
end
end
elseif trace_vsnapping then
report_snapper("mvl %a not snapped due to unknown snap specification: %s",nodecodes[id],listtoutf(list))
end
setattr(current,a_snapmethod,0)
end
else
--
end
-- tex.prevdepth = 0
flush("list")
current = getnext(current)
elseif id == penalty_code then
-- natural_penalty = getpenalty(current)
-- if trace then
-- trace_done("removed penalty",current)
-- end
-- head, current = remove_node(head, current, true)
current = getnext(current)
elseif id == kern_code then
if snap and trace_vsnapping and getkern(current) ~= 0 then
report_snapper("kern of %p kept",getkern(current))
end
flush("kern")
current = getnext(current)
elseif id == glue_code then
local subtype = getsubtype(current)
if subtype == userskip_code then
local sc = getattr(current,a_skipcategory) -- has no default, no unset (yet)
local so = getattr(current,a_skiporder) or 1 -- has 1 default, no unset (yet)
local sp = getattr(current,a_skippenalty) -- has no default, no unset (yet)
if sp and sc == penalty then
if where == "page" then
getpagelist()
local p = specialmethods[specialmethod](pagehead,pagetail,current,sp)
if p then
-- todo: other tracer
--
-- if trace then
-- trace_skip("previous special penalty %a is changed to %a using method %a",sp,p,specialmethod)
-- end
special_penalty = sp
sp = p
end
end
if not penalty_data then
penalty_data = sp
elseif penalty_order < so then
penalty_order, penalty_data = so, sp
elseif penalty_order == so and sp > penalty_data then
penalty_data = sp
end
if trace then
trace_skip("penalty in skip",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
elseif not sc then -- if not sc then
if glue_data then
if trace then
trace_done("flush",glue_data)
end
head = insert_node_before(head,current,glue_data)
if trace then
trace_natural("natural",current)
end
current = getnext(current)
else
-- not look back across head
-- todo: prev can be whatsit (latelua)
local previous = getprev(current)
if previous and getid(previous) == glue_code and getsubtype(previous) == userskip_code then
local pwidth, pstretch, pshrink, pstretch_order, pshrink_order = getglue(previous)
local cwidth, cstretch, cshrink, cstretch_order, cshrink_order = getglue(current)
if pstretch_order == 0 and pshrink_order == 0 and cstretch_order == 0 and cshrink_order == 0 then
setglue(previous,pwidth + cwidth, pstretch + cstretch, pshrink + cshrink)
if trace then
trace_natural("removed",current)
end
head, current = remove_node(head, current, true)
if trace then
trace_natural("collapsed",previous)
end
else
if trace then
trace_natural("filler",current)
end
current = getnext(current)
end
else
if trace then
trace_natural("natural (no prev)",current)
end
current = getnext(current)
end
end
glue_order, glue_data = 0, nil
elseif sc == disable or sc == enable then
local next = getnext(current)
if next then
ignore_following = sc == disable
if trace then
trace_skip(sc == disable and "disable" or "enable",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
else
current = next
end
elseif sc == packed then
if trace then
trace_skip("packed",sc,so,sp,current)
end
-- can't happen !
head, current = remove_node(head, current, true)
elseif sc == nowhite then
local next = getnext(current)
if next then
ignore_whitespace = true
head, current = remove_node(head, current, true)
else
current = next
end
elseif sc == discard then
if trace then
trace_skip("discard",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
elseif sc == overlay then
-- todo (overlay following line over previous
if trace then
trace_skip("overlay",sc,so,sp,current)
end
-- beware: head can actually be after the affected nodes as
-- we look back ... some day head will the real head
head, current = check_experimental_overlay(head,current,a_snapmethod)
elseif ignore_following then
if trace then
trace_skip("disabled",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
elseif not glue_data then
if trace then
trace_skip("assign",sc,so,sp,current)
end
glue_order = so
head, current, glue_data = remove_node(head, current)
elseif glue_order < so then
if trace then
trace_skip("force",sc,so,sp,current)
end
glue_order = so
flush_node(glue_data)
head, current, glue_data = remove_node(head, current)
elseif glue_order == so then
-- is now exclusive, maybe support goback as combi, else why a set
if sc == largest then
local cw = getwidth(current)
local gw = getwidth(glue_data)
if cw > gw then
if trace then
trace_skip("largest",sc,so,sp,current)
end
flush_node(glue_data)
head, current, glue_data = remove_node(head,current)
else
if trace then
trace_skip("remove smallest",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
end
elseif sc == goback then
if trace then
trace_skip("goback",sc,so,sp,current)
end
flush_node(glue_data)
head, current, glue_data = remove_node(head,current)
elseif sc == force then
-- last one counts, some day we can provide an accumulator and largest etc
-- but not now
if trace then
trace_skip("force",sc,so,sp,current)
end
flush_node(glue_data)
head, current, glue_data = remove_node(head, current)
elseif sc == penalty then
if trace then
trace_skip("penalty",sc,so,sp,current)
end
flush_node(glue_data)
glue_data = nil
head, current = remove_node(head, current, true)
elseif sc == add then
if trace then
trace_skip("add",sc,so,sp,current)
end
local cwidth, cstretch, cshrink = getglue(current)
local gwidth, gstretch, gshrink = getglue(glue_data)
setglue(old,gwidth + cwidth, gstretch + cstretch, gshrink + cshrink)
-- toto: order
head, current = remove_node(head, current, true)
else
if trace then
trace_skip("unknown",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
end
else
if trace then
trace_skip("unknown",sc,so,sp,current)
end
head, current = remove_node(head, current, true)
end
if sc == force then
force_glue = true
end
elseif subtype == lineskip_code then
if snap then
local s = getattr(current,a_snapmethod)
if s and s ~= 0 then
setattr(current,a_snapmethod,0)
setwidth(current,0)
if trace_vsnapping then
report_snapper("lineskip set to zero")
end
else
if trace then
trace_skip("lineskip",sc,so,sp,current)
end
flush("lineskip")
end
else
if trace then
trace_skip("lineskip",sc,so,sp,current)
end
flush("lineskip")
end
current = getnext(current)
elseif subtype == baselineskip_code then
if snap then
local s = getattr(current,a_snapmethod)
if s and s ~= 0 then
setattr(current,a_snapmethod,0)
setwidth(current,0)
if trace_vsnapping then
report_snapper("baselineskip set to zero")
end
else
if trace then
trace_skip("baselineskip",sc,so,sp,current)
end
flush("baselineskip")
end
else
if trace then
trace_skip("baselineskip",sc,so,sp,current)
end
flush("baselineskip")
end
current = getnext(current)
elseif subtype == parskip_code then
-- parskip always comes later
if ignore_whitespace then
if trace then
trace_natural("ignored parskip",current)
end
head, current = remove_node(head, current, true)
elseif glue_data then
local w = getwidth(current)
if (w ~= 0) and (w > getwidth(glue_data)) then
glue_data = current
if trace then
trace_natural("taking parskip",current)
end
head, current = remove_node(head, current)
else
if trace then
trace_natural("removed parskip",current)
end
head, current = remove_node(head, current, true)
end
else
if trace then
trace_natural("honored parskip",current)
end
head, current, glue_data = remove_node(head, current)
end
elseif subtype == topskip_code or subtype == splittopskip_code then
local next = getnext(current)
if next and getattr(next,a_skipcategory) == notopskip then
nuts.setglue(current) -- zero
end
if snap then
local s = getattr(current,a_snapmethod)
if s and s ~= 0 then
setattr(current,a_snapmethod,0)
local sv = snapmethods[s]
local w, cw = snap_topskip(current,sv)
if trace_vsnapping then
report_snapper("topskip snapped from %p to %p for %a",w,cw,where)
end
else
if trace then
trace_skip("topskip",sc,so,sp,current)
end
flush("topskip")
end
else
if trace then
trace_skip("topskip",sc,so,sp,current)
end
flush("topskip")
end
current = getnext(current)
elseif subtype == abovedisplayskip_code and remove_math_skips then
--
if trace then
trace_skip("above display skip (normal)",sc,so,sp,current)
end
flush("above display skip (normal)")
current = getnext(current)
--
elseif subtype == belowdisplayskip_code and remove_math_skips then
--
if trace then
trace_skip("below display skip (normal)",sc,so,sp,current)
end
flush("below display skip (normal)")
current = getnext(current)
--
elseif subtype == abovedisplayshortskip_code and remove_math_skips then
--
if trace then
trace_skip("above display skip (short)",sc,so,sp,current)
end
flush("above display skip (short)")
current = getnext(current)
--
elseif subtype == belowdisplayshortskip_code and remove_math_skips then
--
if trace then
trace_skip("below display skip (short)",sc,so,sp,current)
end
flush("below display skip (short)")
current = getnext(current)
--
else -- other glue
if snap and trace_vsnapping then
local w = getwidth(current)
if w ~= 0 then
report_snapper("glue %p of type %a kept",w,gluecodes[subtype])
end
end
if trace then
trace_skip(formatters["glue of type %a"](subtype),sc,so,sp,current)
end
flush("some glue")
current = getnext(current)
end
else
flush(formatters["node with id %a"](id))
current = getnext(current)
end
end
if trace then
trace_info("stop analyzing",where,what)
end
-- if natural_penalty and (not penalty_data or natural_penalty > penalty_data) then
-- penalty_data = natural_penalty
-- end
if trace and (glue_data or penalty_data) then
trace_info("start flushing",where,what)
end
local tail
if penalty_data then
tail = find_node_tail(head)
local p = new_penalty(penalty_data)
if trace then
trace_done("result",p)
end
setlink(tail,p)
-- if penalty_data > special_penalty_min and penalty_data < special_penalty_max then
local props = properties[p]
if props then
props.special_penalty = special_penalty or penalty_data
else
properties[p] = {
special_penalty = special_penalty or penalty_data
}
end
-- end
end
if glue_data then
if not tail then tail = find_node_tail(head) end
if trace then
trace_done("result",glue_data)
end
if force_glue then
head, tail = forced_skip(head,tail,getwidth(glue_data),"after",trace)
flush_node(glue_data)
glue_data = nil
elseif tail then
setlink(tail,glue_data)
else
head = glue_data
end
texnest[texnest.ptr].prevdepth = 0 -- appending to the list bypasses tex's prevdepth handler
end
if trace then
if glue_data or penalty_data then
trace_info("stop flushing",where,what)
end
show_tracing(head)
if oldhead ~= head then
trace_info("head has been changed from %a to %a",nodecodes[getid(oldhead)],nodecodes[getid(head)])
end
end
return head
end
-- alignment after_output end box new_graf vmode_par hmode_par insert penalty before_display after_display
-- \par -> vmode_par
--
-- status.best_page_break
-- tex.lists.best_page_break
-- tex.lists.best_size (natural size to best_page_break)
-- tex.lists.least_page_cost (badness of best_page_break)
-- tex.lists.page_head
-- tex.lists.contrib_head
-- do
local stackhead, stacktail, stackhack = nil, nil, false
local function report(message,where,lst)
if lst and where then
report_vspacing(message,where,count_nodes(lst,true),nodeidstostring(lst))
else
report_vspacing(message,count_nodes(lst,true),nodeidstostring(lst))
end
end
-- ugly code: we get partial lists (check if this stack is still okay) ... and we run
-- into temp nodes (sigh)
local forceflush = false
function vspacing.pagehandler(newhead,where)
-- local newhead = texlists.contrib_head
if newhead then
local newtail = find_node_tail(newhead) -- best pass that tail, known anyway
local flush = false
stackhack = true -- todo: only when grid snapping once enabled
-- todo: fast check if head = tail
for n, id, subtype in nextnode, newhead do -- we could just look for glue nodes
if id ~= glue_code then
flush = true
elseif subtype == userskip_code then
if getattr(n,a_skipcategory) then
stackhack = true
else
flush = true
end
elseif subtype == parskip_code then
-- if where == new_graf then ... end
if texgetcount("c_spac_vspacing_ignore_parskip") > 0 then
-- texsetcount("c_spac_vspacing_ignore_parskip",0)
setglue(n)
-- maybe removenode
end
end
end
texsetcount("c_spac_vspacing_ignore_parskip",0)
if forceflush then
forceflush = false
flush = true
end
if flush then
if stackhead then
if trace_collect_vspacing then report("%s > appending %s nodes to stack (final): %s",where,newhead) end
setlink(stacktail,newhead)
newhead = stackhead
stackhead = nil
stacktail = nil
end
if stackhack then
stackhack = false
if trace_collect_vspacing then report("%s > processing %s nodes: %s",where,newhead) end
-- texlists.contrib_head = collapser(newhead,"page",where,trace_page_vspacing,true,a_snapmethod)
newhead = collapser(newhead,"page",where,trace_page_vspacing,true,a_snapmethod)
else
if trace_collect_vspacing then report("%s > flushing %s nodes: %s",where,newhead) end
-- texlists.contrib_head = newhead
end
return newhead
else
if stackhead then
if trace_collect_vspacing then report("%s > appending %s nodes to stack (intermediate): %s",where,newhead) end
setlink(stacktail,newhead)
else
if trace_collect_vspacing then report("%s > storing %s nodes in stack (initial): %s",where,newhead) end
stackhead = newhead
end
stacktail = newtail
end
end
return nil
end
-- function vspacing.flushpagestack()
-- if stackhead then
-- local head = texlists.contrib_head
-- if head then
-- local tail = find_node_tail(head)
-- setlink(tail,stackhead)
-- else
-- texlists.contrib_head = tonode(stackhead)
-- end
-- stackhead, stacktail = nil, nil
-- end
--
-- end
function vspacing.pageoverflow()
local h = 0
if stackhead then
for n, id in nextnode, stackhead do
if id == glue_code then
h = h + getwidth(n)
elseif id == kern_code then
h = h + getkern(n)
end
end
end
return h
end
function vspacing.forcepageflush()
forceflush = true
end
local ignore = table.tohash {
"split_keep",
"split_off",
-- "vbox",
}
function vspacing.vboxhandler(head,where)
if head and not ignore[where] and getnext(head) then
if getnext(head) then -- what if a one liner and snapping?
head = collapser(head,"vbox",where,trace_vbox_vspacing,true,a_snapvbox) -- todo: local snapper
return head
end
end
return head
end
function vspacing.collapsevbox(n,aslist) -- for boxes but using global a_snapmethod
local box = getbox(n)
if box then
local list = getlist(box)
if list then
list = collapser(list,"snapper","vbox",trace_vbox_vspacing,true,a_snapmethod)
if aslist then
setlist(box,list) -- beware, dimensions of box are wrong now
else
setlist(box,vpack_node(list))
end
end
end
end
end
-- This one is needed to prevent bleeding of prevdepth to the next page
-- which doesn't work well with forced skips. I'm not that sure if the
-- following is a good way out.
do
local outer = texnest[0]
local enabled = true
local trace = false
local report = logs.reporter("vspacing")
trackers.register("vspacing.synchronizepage",function(v)
trace = v
end)
directives.register("vspacing.synchronizepage",function(v)
enabled = v
end)
local ignoredepth = -65536000
-- A previous version analyzed the number of lines moved to the next page in
-- synchronizepage because prevgraf is unreliable in that case. However, we cannot
-- tweak that parameter because it is also used in postlinebreak and hangafter, so
-- there is a danger for interference. Therefore we now do it dynamically.
-- We can also support other lists but there prevgraf probably is ok.
function vspacing.getnofpreviouslines(head)
if enabled then
if not thead then
head = texlists.page_head
end
local noflines = 0
if head then
local tail = find_node_tail(tonut(head))
while tail do
local id = getid(tail)
if id == hlist_code then
if getsubtype(tail) == linelist_code then
noflines = noflines + 1
else
break
end
elseif id == vlist_code then
break
elseif id == glue_code then
local subtype = getsubtype(tail)
if subtype == baselineskip_code or subtype == lineskip_code then
-- we're ok
elseif subtype == parskip_code then
if getwidth(tail) > 0 then
break
else
-- we assume we're ok
end
end
elseif id == penalty_code then
-- we're probably ok
elseif id == rule_code or id == kern_code then
break
else
-- ins, mark, boundary, whatsit
end
tail = getprev(tail)
end
end
return noflines
end
end
interfaces.implement {
name = "getnofpreviouslines",
public = true,
actions = vspacing.getnofpreviouslines,
}
function vspacing.synchronizepage()
if enabled then
if trace then
local newdepth = outer.prevdepth
local olddepth = newdepth
if not texlists.page_head then
newdepth = ignoredepth
texset("prevdepth",ignoredepth)
outer.prevdepth = ignoredepth
end
report("page %i, prevdepth %p => %p",texgetcount("realpageno"),olddepth,newdepth)
-- report("list %s",nodes.idsandsubtypes(head))
else
if not texlists.page_head then
texset("prevdepth",ignoredepth)
outer.prevdepth = ignoredepth
end
end
end
end
local trace = false
trackers.register("vspacing.forcestrutdepth",function(v) trace = v end)
function vspacing.forcestrutdepth(n,depth,trace_mode)
local box = texgetbox(n)
if box then
box = tonut(box)
local head = getlist(box)
if head then
local tail = find_node_tail(head)
if tail and getid(tail) == hlist_code then
local dp = getdepth(tail)
if dp < depth then
setdepth(tail,depth)
outer.prevdepth = depth
if trace or trace_mode > 0 then
nuts.setvisual(tail,"depth")
end
end
end
end
end
end
end
-- interface
do
implement {
name = "vspacing",
actions = vspacing.analyze,
scope = "private",
arguments = "string"
}
implement {
name = "synchronizepage",
actions = vspacing.synchronizepage,
scope = "private"
}
implement {
name = "forcestrutdepth",
arguments = { "integer", "dimension", "integer" },
actions = vspacing.forcestrutdepth,
scope = "private"
}
implement {
name = "vspacingsetamount",
actions = vspacing.setskip,
scope = "private",
arguments = "string",
}
implement {
name = "vspacingdefine",
actions = vspacing.setmap,
scope = "private",
arguments = "2 strings",
}
implement {
name = "vspacingcollapse",
actions = vspacing.collapsevbox,
scope = "private",
arguments = "integer"
}
implement {
name = "vspacingcollapseonly",
actions = vspacing.collapsevbox,
scope = "private",
arguments = { "integer", true }
}
implement {
name = "vspacingsnap",
actions = vspacing.snapbox,
scope = "private",
arguments = { "integer", "integer" }
}
implement {
name = "definesnapmethod",
actions = vspacing.definesnapmethod,
scope = "private",
arguments = "2 strings",
}
-- local remove_node = nodes.remove
-- local find_node_tail = nodes.tail
--
-- interfaces.implement {
-- name = "fakenextstrutline",
-- actions = function()
-- local head = texlists.page_head
-- if head then
-- local head = remove_node(head,find_node_tail(head),true)
-- texlists.page_head = head
-- buildpage()
-- end
-- end
-- }
implement {
name = "removelastline",
actions = function()
local head = texlists.page_head
if head then
local tail = find_node_tail(head)
if tail then
-- maybe check for hlist subtype 1
local head = remove_node(head,tail,true)
texlists.page_head = head
buildpage()
end
end
end
}
implement {
name = "showpagelist", -- will improve
actions = function()
local head = texlists.page_head
if head then
print("start")
while head do
print(" " .. tostring(head))
head = head.next
end
end
end
}
implement {
name = "pageoverflow",
actions = { vspacing.pageoverflow, context }
}
implement {
name = "forcepageflush",
actions = vspacing.forcepageflush
}
end
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