if not modules then modules = { } end modules ['font-imp-quality'] = {
version = 1.001,
comment = "companion to font-ini.mkiv and hand-ini.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
if not context then return end
local next, type, tonumber = next, type, tonumber
local fonts = fonts
local utilities = utilities
local handlers = fonts.handlers
local otf = handlers.otf
local afm = handlers.afm
local registerotffeature = otf.features.register
local registerafmfeature = afm.features.register
local allocate = utilities.storage.allocate
local getparameters = utilities.parsers.getparameters
local implement = interfaces and interfaces.implement
local trace_protrusion = false trackers.register("fonts.protrusion", function(v) trace_protrusion = v end)
local trace_expansion = false trackers.register("fonts.expansion", function(v) trace_expansion = v end)
local report_expansions = logs.reporter("fonts","expansions")
local report_protrusions = logs.reporter("fonts","protrusions")
-- -- -- -- -- --
-- shared
-- -- -- -- -- --
local function get_class_and_vector(tfmdata,value,where) -- "expansions"
local g_where = tfmdata.goodies and tfmdata.goodies[where]
local f_where = fonts[where]
local g_classes = g_where and g_where.classes
local f_classes = f_where and f_where.classes
local class = (g_classes and g_classes[value]) or (f_classes and f_classes[value])
if class then
local class_vector = class.vector
local g_vectors = g_where and g_where.vectors
local f_vectors = f_where and f_where.vectors
local vector = (g_vectors and g_vectors[class_vector]) or (f_vectors and f_vectors[class_vector])
return class, vector
end
end
-- -- -- -- -- --
-- expansion (hz)
-- -- -- -- -- --
local expansions = fonts.expansions or allocate()
fonts.expansions = expansions
local classes = expansions.classes or allocate()
local vectors = expansions.vectors or allocate()
expansions.classes = classes
expansions.vectors = vectors
classes.preset = {
stretch = 2,
shrink = 2,
step = .5,
factor = 1,
}
classes['quality'] = {
stretch = 2,
shrink = 2,
step = .5,
vector = 'default',
factor = 1,
}
vectors['default'] = {
[0x0041] = 0.5, -- A
[0x0042] = 0.7, -- B
[0x0043] = 0.7, -- C
[0x0044] = 0.5, -- D
[0x0045] = 0.7, -- E
[0x0046] = 0.7, -- F
[0x0047] = 0.5, -- G
[0x0048] = 0.7, -- H
[0x004B] = 0.7, -- K
[0x004D] = 0.7, -- M
[0x004E] = 0.7, -- N
[0x004F] = 0.5, -- O
[0x0050] = 0.7, -- P
[0x0051] = 0.5, -- Q
[0x0052] = 0.7, -- R
[0x0053] = 0.7, -- S
[0x0055] = 0.7, -- U
[0x0057] = 0.7, -- W
[0x005A] = 0.7, -- Z
[0x0061] = 0.7, -- a
[0x0062] = 0.7, -- b
[0x0063] = 0.7, -- c
[0x0064] = 0.7, -- d
[0x0065] = 0.7, -- e
[0x0067] = 0.7, -- g
[0x0068] = 0.7, -- h
[0x006B] = 0.7, -- k
[0x006D] = 0.7, -- m
[0x006E] = 0.7, -- n
[0x006F] = 0.7, -- o
[0x0070] = 0.7, -- p
[0x0071] = 0.7, -- q
[0x0073] = 0.7, -- s
[0x0075] = 0.7, -- u
[0x0077] = 0.7, -- w
[0x007A] = 0.7, -- z
[0x0032] = 0.7, -- 2
[0x0033] = 0.7, -- 3
[0x0036] = 0.7, -- 6
[0x0038] = 0.7, -- 8
[0x0039] = 0.7, -- 9
}
vectors['quality'] = vectors['default'] -- metatable ?
local function initialize(tfmdata,value)
if value then
local class, vector = get_class_and_vector(tfmdata,value,"expansions")
if class then
if vector then
local stretch = class.stretch or 0
local shrink = class.shrink or 0
local step = class.step or 0
local factor = class.factor or 1
if trace_expansion then
report_expansions("setting class %a, vector %a, factor %a, stretch %a, shrink %a, step %a",
value,class.vector,factor,stretch,shrink,step)
end
tfmdata.parameters.expansion = {
stretch = 10 * stretch,
shrink = 10 * shrink,
step = 10 * step,
factor = factor,
}
local data = characters and characters.data
for i, chr in next, tfmdata.characters do
local v = vector[i]
if data and not v then -- we could move the data test outside (needed for plain)
local d = data[i]
if d then
local s = d.shcode
if not s then
-- sorry
elseif type(s) == "table" then
v = ((vector[s[1]] or 0) + (vector[s[#s]] or 0)) / 2
else
v = vector[s] or 0
end
end
end
if v and v ~= 0 then
chr.expansion_factor = v*factor
else -- can be option
chr.expansion_factor = factor
end
end
elseif trace_expansion then
report_expansions("unknown vector %a in class %a",class.vector,value)
end
elseif trace_expansion then
report_expansions("unknown class %a",value)
end
end
end
local specification = {
name = "expansion",
description = "apply hz optimization",
initializers = {
base = initialize,
node = initialize,
}
}
registerotffeature(specification)
registerafmfeature(specification)
fonts.goodies.register("expansions", function(...) return fonts.goodies.report("expansions", trace_expansion, ...) end)
implement {
name = "setupfontexpansion",
arguments = "2 strings",
actions = function(class,settings) getparameters(classes,class,'preset',settings) end
}
-- -- -- -- -- --
-- protrusion
-- -- -- -- -- --
fonts.protrusions = allocate()
local protrusions = fonts.protrusions
protrusions.classes = allocate()
protrusions.vectors = allocate()
local classes = protrusions.classes
local vectors = protrusions.vectors
-- the values need to be revisioned
classes.preset = {
factor = 1,
left = 1,
right = 1,
}
classes['pure'] = { vector = 'pure', factor = 1 }
classes['punctuation'] = { vector = 'punctuation', factor = 1 }
classes['alpha'] = { vector = 'alpha', factor = 1 }
classes['quality'] = { vector = 'quality', factor = 1 }
vectors['pure'] = {
[0x002C] = { 0, 1 }, -- comma
[0x002E] = { 0, 1 }, -- period
[0x003A] = { 0, 1 }, -- colon
[0x003B] = { 0, 1 }, -- semicolon
[0x002D] = { 0, 1 }, -- hyphen
[0x00AD] = { 0, 1 }, -- also hyphen
[0x2013] = { 0, 0.50 }, -- endash
[0x2014] = { 0, 0.33 }, -- emdash
[0x3001] = { 0, 1 }, -- ideographic comma 、
[0x3002] = { 0, 1 }, -- ideographic full stop 。
[0x060C] = { 0, 1 }, -- arabic comma ،
[0x061B] = { 0, 1 }, -- arabic semicolon ؛
[0x06D4] = { 0, 1 }, -- arabic full stop ۔
}
vectors['punctuation'] = {
[0x003F] = { 0, 0.20 }, -- ?
[0x00BF] = { 0.20, 0 }, -- ¿
[0x0021] = { 0, 0.20 }, -- !
[0x00A1] = { 0.20, 0, }, -- ¡
[0x0028] = { 0.05, 0 }, -- (
[0x0029] = { 0, 0.05 }, -- )
[0x005B] = { 0.05, 0 }, -- [
[0x005D] = { 0, 0.05 }, -- ]
[0x002C] = { 0, 0.70 }, -- comma
[0x002E] = { 0, 0.70 }, -- period
[0x003A] = { 0, 0.50 }, -- colon
[0x003B] = { 0, 0.50 }, -- semicolon
[0x002D] = { 0, 0.70 }, -- hyphen
[0x00AD] = { 0, 0.70 }, -- also hyphen
[0x2013] = { 0, 0.30 }, -- endash
[0x2014] = { 0, 0.20 }, -- emdash
[0x060C] = { 0, 0.70 }, -- arabic comma
[0x061B] = { 0, 0.50 }, -- arabic semicolon
[0x06D4] = { 0, 0.70 }, -- arabic full stop
[0x061F] = { 0, 0.20 }, -- ؟
-- todo: left and right quotes: .5 double, .7 single
[0x2039] = { 0.70, 0.70 }, -- left single guillemet ‹
[0x203A] = { 0.70, 0.70 }, -- right single guillemet ›
[0x00AB] = { 0.50, 0.50 }, -- left guillemet «
[0x00BB] = { 0.50, 0.50 }, -- right guillemet »
[0x2018] = { 0.70, 0.70 }, -- left single quotation mark ‘
[0x2019] = { 0, 0.70 }, -- right single quotation mark ’
[0x201A] = { 0.70, 0 }, -- single low-9 quotation mark ,
[0x201B] = { 0.70, 0 }, -- single high-reversed-9 quotation mark ‛
[0x201C] = { 0.50, 0.50 }, -- left double quotation mark “
[0x201D] = { 0, 0.50 }, -- right double quotation mark ”
[0x201E] = { 0.50, 0 }, -- double low-9 quotation mark „
[0x201F] = { 0.50, 0 }, -- double high-reversed-9 quotation mark ‟
}
vectors['alpha'] = {
[0x0041] = { .05, .05 }, -- A
[0x0046] = { 0, .05 }, -- F
[0x004A] = { .05, 0 }, -- J
[0x004B] = { 0, .05 }, -- K
[0x004C] = { 0, .05 }, -- L
[0x0054] = { .05, .05 }, -- T
[0x0056] = { .05, .05 }, -- V
[0x0057] = { .05, .05 }, -- W
[0x0058] = { .05, .05 }, -- X
[0x0059] = { .05, .05 }, -- Y
[0x006B] = { 0, .05 }, -- k
[0x0072] = { 0, .05 }, -- r
[0x0074] = { 0, .05 }, -- t
[0x0076] = { .05, .05 }, -- v
[0x0077] = { .05, .05 }, -- w
[0x0078] = { .05, .05 }, -- x
[0x0079] = { .05, .05 }, -- y
}
vectors['quality'] = table.merged(
vectors['punctuation'],
vectors['alpha']
)
-- As this is experimental code, users should not depend on it. The implications are still
-- discussed on the ConTeXt Dev List and we're not sure yet what exactly the spec is (the
-- next code is tested with a gyre font patched by / fea file made by Khaled Hosny). The
-- double trick should not be needed it proper hanging punctuation is used in which case
-- values < 1 can be used.
--
-- preferred (in context, usine vectors):
--
-- \definefontfeature[whatever][default][mode=node,protrusion=quality]
--
-- using lfbd and rtbd, with possibibility to enable only one side :
--
-- \definefontfeature[whocares][default][mode=node,protrusion=yes, opbd=yes,script=latn]
-- \definefontfeature[whocares][default][mode=node,protrusion=right,opbd=yes,script=latn]
--
-- idem, using multiplier
--
-- \definefontfeature[whocares][default][mode=node,protrusion=2,opbd=yes,script=latn]
-- \definefontfeature[whocares][default][mode=node,protrusion=double,opbd=yes,script=latn]
--
-- idem, using named feature file (less frozen):
--
-- \definefontfeature[whocares][default][mode=node,protrusion=2,opbd=yes,script=latn,featurefile=texgyrepagella-regularxx.fea]
classes['double'] = { -- for testing opbd
factor = 2,
left = 1,
right = 1,
}
local function map_opbd_onto_protrusion(tfmdata,value,opbd)
local characters = tfmdata.characters
local descriptions = tfmdata.descriptions
local properties = tfmdata.properties
local parameters = tfmdata.parameters
local resources = tfmdata.resources
local rawdata = tfmdata.shared.rawdata
local lookuphash = rawdata.lookuphash
local lookuptags = resources.lookuptags
local script = properties.script
local language = properties.language
local units = parameters.units
local done, factor, left, right = false, 1, 1, 1
local class = classes[value]
if class then
factor = class.factor or 1
left = class.left or 1
right = class.right or 1
else
factor = tonumber(value) or 1
end
local lfactor = left * factor
local rfactor = right * factor
if trace_protrusion then
report_protrusions("left factor %0.3F, right factor %0.3F",lfactor,rfactor)
end
tfmdata.parameters.protrusion = {
factor = factor,
left = left,
right = right,
}
if opbd ~= "right" then
local validlookups, lookuplist = otf.collectlookups(rawdata,"lfbd",script,language)
if validlookups then
for i=1,#lookuplist do
local lookup = lookuplist[i]
local steps = lookup.steps
if steps then
if trace_protrusion then
report_protrusions("setting left using lfbd")
end
for i=1,#steps do
local step = steps[i]
local coverage = step.coverage
if coverage then
for k, v in next, coverage do
if v == true then
-- zero
else
local w = descriptions[k].width
local d = - v[1]
if w == 0 or d == 0 then
-- ignored
else
local p = lfactor * d/units
characters[k].left_protruding = p
if trace_protrusion then
report_protrusions("lfbd -> %0.3F %C",p,k)
end
end
end
end
end
end
done = true
end
end
end
end
if opbd ~= "left" then
local validlookups, lookuplist = otf.collectlookups(rawdata,"rtbd",script,language)
if validlookups then
for i=1,#lookuplist do
local lookup = lookuplist[i]
local steps = lookup.steps
if steps then
if trace_protrusion then
report_protrusions("setting right using rtbd")
end
for i=1,#steps do
local step = steps[i]
local coverage = step.coverage
if coverage then
for k, v in next, coverage do
if v == true then
-- zero
else
local w = descriptions[k].width
local d = - v[3]
if w == 0 or d == 0 then
-- ignored
else
local p = rfactor * d/units
characters[k].right_protruding = p
if trace_protrusion then
report_protrusions("rtbd -> %0.3F %C",p,k)
end
end
end
end
end
end
end
done = true
end
end
end
end
-- The opbd test is just there because it was discussed on the context development list. However,
-- the mentioned fxlbi.otf font only has some kerns for digits. So, consider this feature not supported
-- till we have a proper test font.
local function initialize(tfmdata,value)
if value then
local opbd = tfmdata.shared.features.opbd
if opbd then
-- possible values: left right both yes no (experimental)
map_opbd_onto_protrusion(tfmdata,value,opbd)
else
local class, vector = get_class_and_vector(tfmdata,value,"protrusions")
if class then
if vector then
local factor = class.factor or 1
local left = class.left or 1
local right = class.right or 1
if trace_protrusion then
report_protrusions("setting class %a, vector %a, factor %a, left %a, right %a",
value,class.vector,factor,left,right)
end
local data = characters.data
local lfactor = left * factor
local rfactor = right * factor
if trace_protrusion then
report_protrusions("left factor %0.3F, right factor %0.3F",lfactor,rfactor)
end
tfmdata.parameters.protrusion = {
factor = factor,
left = left,
right = right,
}
for i, chr in next, tfmdata.characters do
local v = vector[i]
local pl = nil
local pr = nil
if v then
pl = v[1]
pr = v[2]
else
local d = data[i]
if d then
local s = d.shcode
if not s then
-- sorry
elseif type(s) == "table" then
local vl = vector[s[1]]
local vr = vector[s[#s]]
if vl then pl = vl[1] end
if vr then pr = vr[2] end
else
v = vector[s]
if v then
pl = v[1]
pr = v[2]
end
end
end
end
if pl and pl ~= 0 then
local p = pl * lfactor
chr.left_protruding = p
if trace_protrusion then
report_protrusions("left -> %0.3F %C ",p,i)
end
end
if pr and pr ~= 0 then
local p = pr * rfactor
chr.right_protruding = p
if trace_protrusion then
report_protrusions("right -> %0.3F %C",p,i)
end
end
end
elseif trace_protrusion then
report_protrusions("unknown vector %a in class %a",class.vector,value)
end
elseif trace_protrusion then
report_protrusions("unknown class %a",value)
end
end
end
end
local specification = {
name = "protrusion",
description = "l/r margin character protrusion",
initializers = {
base = initialize,
node = initialize,
}
}
registerotffeature(specification)
registerafmfeature(specification)
fonts.goodies.register("protrusions", function(...) return fonts.goodies.report("protrusions", trace_protrusion, ...) end)
implement {
name = "setupfontprotrusion",
arguments = "2 strings",
actions = function(class,settings) getparameters(classes,class,'preset',settings) end
}
local function initialize(tfmdata,value)
local properties = tfmdata.properties
local parameters = tfmdata.parameters
if properties then
value = tonumber(value)
if value then
if value < 0 then
value = 0
elseif value > 10 then
report_expansions("threshold for %a @ %p limited to 10 pct",properties.fontname,parameters.size)
value = 10
end
if value > 5 then
report_expansions("threshold for %a @ %p exceeds 5 pct",properties.fontname,parameters.size)
end
end
properties.threshold = value or nil -- nil enforces default
end
end
local specification = {
name = "threshold",
description = "threshold for quality features",
initializers = {
base = initialize,
node = initialize,
}
}
registerotffeature(specification)
registerafmfeature(specification)
