if not modules then modules = { } end modules ['good-mth'] = {
version = 1.000,
comment = "companion to font-lib.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
local type, next = type, next
local ceil = math.ceil
local fonts = fonts
local trace_goodies = false trackers.register("fonts.goodies", function(v) trace_goodies = v end)
local report_goodies = logs.reporter("fonts","goodies")
local registerotffeature = fonts.handlers.otf.features.register
local fontgoodies = fonts.goodies or { }
local fontcharacters = fonts.hashes.characters
local nuts = nodes.nuts
local setlink = nuts.setlink
local nodepool = nuts.pool
local new_kern = nodepool.kern
local new_glyph = nodepool.glyph
local new_hlist = nodepool.hlist
local new_vlist = nodepool.vlist
local insert_node_after = nuts.insert_after
-- experiment, we have to load the definitions immediately as they precede
-- the definition so they need to be initialized in the typescript
local function finalize(tfmdata,feature,value)
mathematics.overloaddimensions(tfmdata,tfmdata,value)
end
registerotffeature {
name = "mathdimensions",
description = "manipulate math dimensions",
-- default = true,
manipulators = {
base = finalize,
node = finalize,
}
}
local function initialize(goodies)
local mathgoodies = goodies.mathematics
if mathgoodies then
local virtuals = mathgoodies.virtuals
local mapfiles = mathgoodies.mapfiles
local maplines = mathgoodies.maplines
if virtuals then
for name, specification in next, virtuals do
-- beware, they are all constructed
mathematics.makefont(name,specification,goodies)
end
end
if mapfiles then
for i=1,#mapfiles do
fonts.mappings.loadfile(mapfiles[i]) -- todo: backend function
end
end
if maplines then
for i=1,#maplines do
fonts.mappings.loadline(maplines[i]) -- todo: backend function
end
end
end
end
fontgoodies.register("mathematics", initialize)
local enabled = false directives.register("fontgoodies.mathkerning",function(v) enabled = v end)
local function initialize(tfmdata)
if enabled and tfmdata.mathparameters then -- funny, cambria text has this
local goodies = tfmdata.goodies
if goodies then
local characters = tfmdata.characters
if characters[0x1D44E] then -- 119886
-- we have at least an italic a
for i=1,#goodies do
local mathgoodies = goodies[i].mathematics
if mathgoodies then
local kerns = mathgoodies.kerns
if kerns then
for unicode, specification in next, kerns do
local chardata = characters[unicode]
if chardata and (not chardata.mathkerns or specification.force) then
chardata.mathkerns = specification
end
end
return
end
end
end
else
return -- no proper math font anyway
end
end
end
end
registerotffeature {
name = "mathkerns",
description = "math kerns",
default = true,
initializers = {
base = initialize,
node = initialize,
}
}
-- math italics (not really needed)
--
-- it would be nice to have a \noitalics\font option
local function initialize(tfmdata)
local goodies = tfmdata.goodies
if goodies then
local shared = tfmdata.shared
for i=1,#goodies do
local mathgoodies = goodies[i].mathematics
if mathgoodies then
local mathitalics = mathgoodies.italics
if mathitalics then
local properties = tfmdata.properties
if properties.setitalics then
mathitalics = mathitalics[file.nameonly(properties.name)] or mathitalics
if mathitalics then
if trace_goodies then
report_goodies("loading mathitalics for font %a",properties.name)
end
local corrections = mathitalics.corrections
local defaultfactor = mathitalics.defaultfactor
-- properties.mathitalic_defaultfactor = defaultfactor -- we inherit outer one anyway (name will change)
if corrections then
fontgoodies.registerpostprocessor(tfmdata, function(tfmdata) -- this is another tfmdata (a copy)
-- better make a helper so that we have less code being defined
local properties = tfmdata.properties
local parameters = tfmdata.parameters
local characters = tfmdata.characters
properties.mathitalic_defaultfactor = defaultfactor
properties.mathitalic_defaultvalue = defaultfactor * parameters.quad
if trace_goodies then
report_goodies("assigning mathitalics for font %a",properties.name)
end
local quad = parameters.quad
local hfactor = parameters.hfactor
for k, v in next, corrections do
local c = characters[k]
if c then
if v > -1 and v < 1 then
c.italic = v * quad
else
c.italic = v * hfactor
end
else
report_goodies("invalid mathitalics entry %U for font %a",k,properties.name)
end
end
end)
end
return -- maybe not as these can accumulate
end
end
end
end
end
end
end
registerotffeature {
name = "mathitalics",
description = "additional math italic corrections",
-- default = true,
initializers = {
base = initialize,
node = initialize,
}
}
-- fontgoodies.register("mathitalics", initialize)
local function mathradicalaction(n,h,v,font,mchar,echar)
local characters = fontcharacters[font]
local mchardata = characters[mchar]
local echardata = characters[echar]
local ewidth = echardata.width
local mwidth = mchardata.width
local delta = h - ewidth
local glyph = new_glyph(font,echar)
local head = glyph
if delta > 0 then
local count = ceil(delta/mwidth)
local kern = (delta - count * mwidth) / count
for i=1,count do
local k = new_kern(kern)
local g = new_glyph(font,mchar)
setlink(k,head)
setlink(g,k)
head = g
end
end
local height = mchardata.height
local list = new_hlist(head)
local kern = new_kern(height-v)
list = setlink(kern,list)
local list = new_vlist(kern)
insert_node_after(n,n,list)
end
local function mathhruleaction(n,h,v,font,bchar,mchar,echar)
local characters = fontcharacters[font]
local bchardata = characters[bchar]
local mchardata = characters[mchar]
local echardata = characters[echar]
local bwidth = bchardata.width
local mwidth = mchardata.width
local ewidth = echardata.width
local delta = h - ewidth - bwidth
local glyph = new_glyph(font,echar)
local head = glyph
if delta > 0 then
local count = ceil(delta/mwidth)
local kern = (delta - count * mwidth) / (count+1)
for i=1,count do
local k = new_kern(kern)
local g = new_glyph(font,mchar)
setlink(k,head)
setlink(g,k)
head = g
end
local k = new_kern(kern)
setlink(k,head)
head = k
end
local g = new_glyph(font,bchar)
setlink(g,head)
head = g
local height = mchardata.height
local list = new_hlist(head)
local kern = new_kern(height-v)
list = setlink(kern,list)
local list = new_vlist(kern)
insert_node_after(n,n,list)
end
local function initialize(tfmdata)
local goodies = tfmdata.goodies
if goodies then
local resources = tfmdata.resources
local ruledata = { }
for i=1,#goodies do
local mathematics = goodies[i].mathematics
if mathematics then
local rules = mathematics.rules
if rules then
for tag, name in next, rules do
ruledata[tag] = name
end
end
end
end
if next(ruledata) then
local characters = tfmdata.characters
local unicodes = resources.unicodes
if characters and unicodes then
local mathruleactions = resources.mathruleactions
if not mathruleactions then
mathruleactions = { }
resources.mathruleactions = mathruleactions
end
--
local mchar = unicodes[ruledata["radical.extender"] or false]
local echar = unicodes[ruledata["radical.end"] or false]
if mchar and echar then
mathruleactions.radicalaction = function(n,h,v,font)
mathradicalaction(n,h,v,font,mchar,echar)
end
end
--
local bchar = unicodes[ruledata["hrule.begin"] or false]
local mchar = unicodes[ruledata["hrule.extender"] or false]
local echar = unicodes[ruledata["hrule.end"] or false]
if bchar and mchar and echar then
mathruleactions.hruleaction = function(n,h,v,font)
mathhruleaction(n,h,v,font,bchar,mchar,echar)
end
end
-- not that nice but we need to register it at the tex end
-- context.enablemathrules("\\fontclass")
end
end
end
end
registerotffeature {
name = "mathrules",
description = "check math rules",
default = true,
initializers = {
base = initialize,
node = initialize,
}
}
