diff options
| -rw-r--r-- | luaotfload-extralibs.lua | 403 |
1 files changed, 403 insertions, 0 deletions
diff --git a/luaotfload-extralibs.lua b/luaotfload-extralibs.lua new file mode 100644 index 0000000..f192d1e --- /dev/null +++ b/luaotfload-extralibs.lua @@ -0,0 +1,403 @@ +if not modules then modules = { } end modules ["extralibs"] = { + version = 2.200, + comment = "companion to luaotfload.lua", + author = "Hans Hagen, Philipp Gesang", + copyright = "PRAGMA ADE / ConTeXt Development Team", + license = "GPL v.2.0", +} + +-- extralibs: set up an emulation layer to load additional Context +-- libraries + +--===================================================================-- +--- PREPARE +--===================================================================-- + +local getmetatable = getmetatable +local require = require +local select = select +local setmetatable = setmetatable +local tonumber = tonumber + +local texattribute = tex.attribute + +local new_node = node.new +local copy_node = node.copy + +----------------------------------------------------------------------- +--- namespace +----------------------------------------------------------------------- + +--- The “typesetters” namespace isn’t bad at all; there is no need +--- to remove it after loading. + +typesetters = typesetters or { } +local typesetters = typesetters +typesetters.kerns = typesetters.kerns or { } +local kerns = typesetters.kerns +kerns.mapping = kerns.mapping or { } +kerns.factors = kerns.factors or { } + +local namespace = "kern" --- <= attribute <= plugin.name +local callback_name = "typesetters.kerncharacters" + +----------------------------------------------------------------------- +--- node-ini +----------------------------------------------------------------------- + +nodes = nodes or { } --- should be present with luaotfload +local bothways = function (t) return table.swapped (t, t) end + +nodes.kerncodes = bothways({ + [0] = "fontkern", + [1] = "userkern", + [2] = "accentkern", +}) + +nodes.skipcodes = bothways({ + [ 0] = "userskip", + [ 1] = "lineskip", + [ 2] = "baselineskip", + [ 3] = "parskip", + [ 4] = "abovedisplayskip", + [ 5] = "belowdisplayskip", + [ 6] = "abovedisplayshortskip", + [ 7] = "belowdisplayshortskip", + [ 8] = "leftskip", + [ 9] = "rightskip", + [ 10] = "topskip", + [ 11] = "splittopskip", + [ 12] = "tabskip", + [ 13] = "spaceskip", + [ 14] = "xspaceskip", + [ 15] = "parfillskip", + [ 16] = "thinmuskip", + [ 17] = "medmuskip", + [ 18] = "thickmuskip", + [100] = "leaders", + [101] = "cleaders", + [102] = "xleaders", + [103] = "gleaders", +}) + +----------------------------------------------------------------------- +--- node-res +----------------------------------------------------------------------- + +nodes.pool = nodes.pool or { } +local pool = nodes.pool + +local kern = new_node("kern", nodes.kerncodes.userkern) +local glue_spec = new_node "glue_spec" + +pool.kern = function (k) + local n = copy_node(kern) + n.kern = k + return n +end + +pool.gluespec = function (width, stretch, shrink, + stretch_order, shrink_order) + local s = copy_node(glue_spec) + if width then s.width = width end + if stretch then s.stretch = stretch end + if shrink then s.shrink = shrink end + if stretch_order then s.stretch_order = stretch_order end + if shrink_order then s.shrink_order = shrink_order end + return s +end + +pool.glue = function (width, stretch, shrink, + stretch_order, shrink_order) + local n = new_node"glue" + if not width then + -- no spec + elseif width == false or tonumber(width) then + local s = copy_node(glue_spec) + if width then s.width = width end + if stretch then s.stretch = stretch end + if shrink then s.shrink = shrink end + if stretch_order then s.stretch_order = stretch_order end + if shrink_order then s.shrink_order = shrink_order end + n.spec = s + else + -- shared + n.spec = copy_node(width) + end + return n +end + +----------------------------------------------------------------------- +--- font-hsh +----------------------------------------------------------------------- +--- some initialization resembling font-hsh +local fonthashes = fonts.hashes +local identifiers = fonthashes.identifiers --- was: fontdata +local chardata = fonthashes.characters +local quaddata = fonthashes.quads +local markdata = fonthashes.marks +local parameters = fonthashes.parameters + +--- ('a, 'a) hash -> (('a, 'a) hash -> 'a -> 'a) -> ('a, 'a) hash +local setmetatableindex = function (t, f) + local mt = getmetatable(t) + if mt then + mt.__index = f + else + setmetatable(t, { __index = f }) + end + return t +end + +if not parameters then + parameters = { } + setmetatableindex(parameters, function(t, k) + if k == true then + return parameters[currentfont()] + else + local parameters = identifiers[k].parameters + t[k] = parameters + return parameters + end + end) + fonthashes.parameters = parameters +end + +if not chardata then + chardata = { } + setmetatableindex(chardata, function(t, k) + if k == true then + return chardata[currentfont()] + else + local characters = identifiers[k].characters + t[k] = characters + return characters + end + end) + fonthashes.characters = chardata +end + +if not quaddata then + quaddata = { } + setmetatableindex(quaddata, function(t, k) + if k == true then + return quads[currentfont()] + else + local parameters = parameters[k] + local quad = parameters and parameters.quad or 0 + t[k] = quad + return quad + end + end) + fonthashes.quads = quaddata +end + +if not markdata then + markdata = { } + setmetatableindex(markdata, function(t, k) + if k == true then + return marks[currentfont()] + else + local resources = identifiers[k].resources or { } + local marks = resources.marks or { } + t[k] = marks + return marks + end + end) + fonthashes.marks = markdata +end + +interfaces = interfaces or { } +interfaces.variables = interfaces.variables or { } +interfaces.variables.max = "max" + +----------------------------------------------------------------------- +--- attr-ini +----------------------------------------------------------------------- + +attributes = attributes or { } --- to be removed with cleanup + +local hidden = { + a_kerns = luatexbase.new_attribute("typo-krn:a_kerns", true), + a_fontkern = luatexbase.new_attribute("typo-krn:a_fontkern", true), +} + +attributes.private = attributes.private or function (attr_name) + local res = hidden[attr_name] + if not res then + res = luatexbase.new_attribute(attr_name) + end + return res +end + +attributes.unsetvalue = luatexbase.get_unset_value() + +----------------------------------------------------------------------- +--- luat-sto +----------------------------------------------------------------------- + +--- Storage is so ridiculously well designed in Context it’s a pity +--- we can’t just force every package author to use it. + +storage = storage or { } +storage.register = storage.register or function (...) + local t = { ... } + --- sorry + return t +end + +----------------------------------------------------------------------- +--- node-fin +----------------------------------------------------------------------- + +local plugin_store = { } + +local installattributehandler = function (plugin) + --- Context has some load() magic here. + plugin_store[plugin.name] = plugin.processor +end + +nodes.installattributehandler = installattributehandler + +----------------------------------------------------------------------- +--- node-tsk +----------------------------------------------------------------------- + +nodes.tasks = nodes.tasks or { } +nodes.tasks.enableaction = function () end + +----------------------------------------------------------------------- +--- core-ctx +----------------------------------------------------------------------- + +commands = commands or { } + +--===================================================================-- +--- LOAD +--===================================================================-- + +--- we should be ready at this moment to insert the library + +require "typo-krn" + +--===================================================================-- +--- CLEAN +--===================================================================-- +--- interface +----------------------------------------------------------------------- + +local factors = kerns.factors +local mapping = kerns.mapping +local unsetvalue = attributes.unset_value +local process_kerns = plugin_store.kern + +local kerncharacters = function (head) + return process_kerns("kerns", hidden.a_kerns, head) +end + +--- callback wrappers +local add_kern_processor = function (...) + for i=1, select("#", ...) do + luatexbase.add_to_callback( + select(i, ...), kerncharacters, callback_name + ) + end +end +local remove_kern_processor = function (...) + for i=1, select("#", ...) do + luatexbase.remove_from_callback( + select(i, ...), kerncharacters, callback_name + ) + end +end + +--- we use the same callbacks as a node processor in Context +kerns.enablecharacterkerning = function ( ) + add_kern_processor("pre_linebreak_filter", "hpack_filter") +end + +kerns.disablecharacterkerning = function ( ) + remove_kern_processor("pre_linebreak_filter", "hpack_filter") +end + +local enabled = false --- callback state + +--- we just replace the kern enabler with our modified version +kerns.set = function (factor) + if factor ~= v_max then + factor = tonumber(factor) or 0 + end + if factor == v_max or factor ~= 0 then + if not enabled then + kerns.enablecharacterkerning() + enabled = true + end + local a = factors[factor] + if not a then + a = #mapping + 1 + factors[factors], mapping[a] = a, factor + end + factor = a + else + factor = unsetvalue + end + texattribute[hidden.a_kerns] = factor + return factor +end + + +----------------------------------------------------------------------- +--- options +----------------------------------------------------------------------- + +kerns.keepligature = false --- supposed to be of type function +kerns.keeptogether = false --- supposed to be of type function + +----------------------------------------------------------------------- +--- erase fake Context layer +----------------------------------------------------------------------- + +attributes = nil +--commands = nil --- used in lualibs +storage = nil --- not to confuse with utilities.storage +nodes.tasks = nil + +collectgarbage"collect" + +--[[example-- + +\input luaotfload.sty +\RequireLuaModule{letterspace-support.lua} +\def\setcharacterkerning#1{% #1 factor : float + \directlua{typesetters.kerns.set(0.618)}% +} +%directlua{typesetters.kerns.enablecharacterkerning()} + +\font\iwona = "name:Iwona:mode=node" at 42pt +\font\lmregular = "name:Latin Modern Roman:mode=node" at 42pt + +{\iwona + foo + {\setcharacterkerning{0.618}% + bar} + baz} + +{\lmregular + foo {\setcharacterkerning{0.125}ff fi ffi fl Th} baz} + +{\lmregular + \directlua{ %% I’m not exactly sure how those work + typesetters.kerns.keepligature = function (start) + print("[liga]", start) + return true + end + typesetters.kerns.keeptogether = function (start) + print("[keeptogether]", start) + return true + end}% + foo {\setcharacterkerning{0.125}ff fi ffi fl Th} baz} + +\bye +--example]]-- + +-- vim:ts=2:sw=2:expandtab |