Import ConTeXt math modules

Modules that provide OpenType and Unicode math related functionality,
not very tested yet, but it seems to magically fix some of unicode-math
issues.

May be it should be trimmed a bit, since a good chunk of the code is of
no use to us.

1 files changed, 329 insertions, 0 deletions

diff --git a/otfl-math-ini.lua b/otfl-math-ini.lua
new file mode 100644
index 0000000..add198b
--- /dev/null
+++ b/otfl-math-ini.lua
@@ -0,0 +1,329 @@
+if not modules then modules = { } end modules ['math-ext'] = {
+    version   = 1.001,
+    comment   = "companion to math-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- if needed we can use the info here to set up xetex definition files
+-- the "8000 hackery influences direct characters (utf) as indirect \char's
+
+local utf = unicode.utf8
+
+local texsprint, format, utfchar, utfbyte = tex.sprint, string.format, utf.char, utf.byte
+
+local trace_defining = false  trackers.register("math.defining", function(v) trace_defining = v end)
+
+mathematics = mathematics or { }
+
+mathematics.extrabase   = 0xFE000 -- here we push some virtuals
+mathematics.privatebase = 0xFF000 -- here we push the ex
+
+local families = {
+    tf = 0, it = 1, sl = 2, bf = 3, bi = 4, bs = 5, -- virtual fonts or unicode otf
+}
+
+local classes = {
+    ord       =  0,  -- mathordcomm     mathord
+    op        =  1,  -- mathopcomm      mathop
+    bin       =  2,  -- mathbincomm     mathbin
+    rel       =  3,  -- mathrelcomm     mathrel
+    open      =  4,  -- mathopencomm    mathopen
+    close     =  5,  -- mathclosecomm   mathclose
+    punct     =  6,  -- mathpunctcomm   mathpunct
+    alpha     =  7,  -- mathalphacomm   firstofoneargument
+    accent    =  8,  -- class 0
+    radical   =  9,
+    xaccent   = 10,  -- class 3
+    topaccent = 11,  -- class 0
+    botaccent = 12,  -- class 0
+    under     = 13,
+    over      = 14,
+    delimiter = 15,
+    inner     =  0,  -- mathinnercomm   mathinner
+    nothing   =  0,  -- mathnothingcomm firstofoneargument
+    choice    =  0,  -- mathchoicecomm  @@mathchoicecomm
+    box       =  0,  -- mathboxcomm     @@mathboxcomm
+    limop     =  1,  -- mathlimopcomm   @@mathlimopcomm
+    nolop     =  1,  -- mathnolopcomm   @@mathnolopcomm
+}
+
+mathematics.families = families
+mathematics.classes  = classes
+
+classes.alphabetic  = classes.alpha
+classes.unknown     = classes.nothing
+classes.default     = classes.nothing
+classes.punctuation = classes.punct
+classes.normal      = classes.nothing
+classes.opening     = classes.open
+classes.closing     = classes.close
+classes.binary      = classes.bin
+classes.relation    = classes.rel
+classes.fence       = classes.unknown
+classes.diacritic   = classes.accent
+classes.large       = classes.op
+classes.variable    = classes.alphabetic
+classes.number      = classes.alphabetic
+
+-- there will be proper functions soon (and we will move this code in-line)
+-- no need for " in class and family (saves space)
+
+local function delcode(target,family,slot)
+    return format('\\Udelcode%s="%X "%X ',target,family,slot)
+end
+local function mathchar(class,family,slot)
+    return format('\\Umathchar "%X "%X "%X ',class,family,slot)
+end
+local function mathaccent(class,family,slot)
+    return format('\\Umathaccent "%X "%X "%X ',0,family,slot) -- no class
+end
+local function delimiter(class,family,slot)
+    return format('\\Udelimiter "%X "%X "%X ',class,family,slot)
+end
+local function radical(family,slot)
+    return format('\\Uradical "%X "%X ',family,slot)
+end
+local function mathchardef(name,class,family,slot)
+    return format('\\Umathchardef\\%s "%X "%X "%X ',name,class,family,slot)
+end
+local function mathcode(target,class,family,slot)
+    return format('\\Umathcode%s="%X "%X "%X ',target,class,family,slot)
+end
+local function mathtopaccent(class,family,slot)
+    return format('\\Umathaccent "%X "%X "%X ',0,family,slot) -- no class
+end
+local function mathbotaccent(class,family,slot)
+    return format('\\Umathbotaccent "%X "%X "%X ',0,family,slot) -- no class
+end
+local function mathtopdelimiter(class,family,slot)
+    return format('\\Uoverdelimiter "%X "%X ',0,family,slot) -- no class
+end
+local function mathbotdelimiter(class,family,slot)
+    return format('\\Uunderdelimiter "%X "%X ',0,family,slot) -- no class
+end
+
+local escapes = characters.filters.utf.private.escapes
+
+local function setmathsymbol(name,class,family,slot)
+    if class == classes.accent then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathaccent(class,family,slot)))
+    elseif class == classes.topaccent then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathtopaccent(class,family,slot)))
+    elseif class == classes.botaccent then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathbotaccent(class,family,slot)))
+    elseif class == classes.over then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathtopdelimiter(class,family,slot)))
+    elseif class == classes.under then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathbotdelimiter(class,family,slot)))
+    elseif class == classes.open or class == classes.close then
+        texsprint(delcode(slot,family,slot))
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,delimiter(class,family,slot)))
+    elseif class == classes.delimiter then
+        texsprint(delcode(slot,family,slot))
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,delimiter(0,family,slot)))
+    elseif class == classes.radical then
+        texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,radical(family,slot)))
+    else
+        -- beware, open/close and other specials should not end up here
+--~         local ch = utfchar(slot)
+--~         if escapes[ch] then
+--~             texsprint(format("\\xdef\\%s{\\char%s }",name,slot))
+--~         else
+            texsprint(format("\\unexpanded\\xdef\\%s{%s}",name,mathchar(class,family,slot)))
+--~         end
+    end
+end
+
+local function setmathcharacter(class,family,slot,unicode,firsttime)
+    if not firsttime and class <= 7 then
+        texsprint(mathcode(slot,class,family,unicode or slot))
+    end
+end
+
+local function setmathsynonym(class,family,slot,unicode,firsttime)
+    if not firsttime and class <= 7 then
+        texsprint(mathcode(slot,class,family,unicode))
+    end
+    if class == classes.open or class == classes.close then
+        texsprint(delcode(slot,family,unicode))
+    end
+end
+
+local function report(class,family,unicode,name)
+    local nametype = type(name)
+    if nametype == "string" then
+        logs.report("mathematics","%s:%s %s U+%05X (%s) => %s",classname,class,family,unicode,utfchar(unicode),name)
+    elseif nametype == "number" then
+        logs.report("mathematics","%s:%s %s U+%05X (%s) => U+%05X",classname,class,family,unicode,utfchar(unicode),name)
+    else
+        logs.report("mathematics","%s:%s %s U+%05X (%s)", classname,class,family,unicode,utfchar(unicode))
+    end
+end
+
+-- there will be a combined \(math)chardef
+
+function mathematics.define(slots,family)
+    family = family or 0
+    family = families[family] or family
+    local data = characters.data
+    for unicode, character in next, data do
+        local symbol = character.mathsymbol
+        if symbol then
+            local other = data[symbol]
+            local class = other.mathclass
+            if class then
+                class = classes[class] or class -- no real checks needed
+                if trace_defining then
+                    report(class,family,unicode,symbol)
+                end
+                setmathsynonym(class,family,unicode,symbol)
+            end
+            local spec = other.mathspec
+            if spec then
+                for i, m in next, spec do
+                    local class = m.class
+                    if class then
+                        class = classes[class] or class -- no real checks needed
+                        setmathsynonym(class,family,unicode,symbol,i)
+                    end
+                end
+            end
+        end
+        local mathclass = character.mathclass
+        local mathspec = character.mathspec
+        if mathspec then
+            for i, m in next, mathspec do
+                local name = m.name
+                local class = m.class
+                if not class then
+                    class = mathclass
+                elseif not mathclass then
+                    mathclass = class
+                end
+                if class then
+                    class = classes[class] or class -- no real checks needed
+                    if name then
+                        if trace_defining then
+                            report(class,family,unicode,name)
+                        end
+                        setmathsymbol(name,class,family,unicode)
+                    -- setmathcharacter(class,family,unicode,unicode,i)
+                    else
+                        name = class == classes.variable or class == classes.number and character.adobename
+                        if name then
+                            if trace_defining then
+                                report(class,family,unicode,name)
+                            end
+                        --  setmathcharacter(class,family,unicode,unicode,i)
+                        end
+                    end
+                    setmathcharacter(class,family,unicode,unicode,i)
+                end
+            end
+        end
+        if mathclass then
+            local name = character.mathname
+            local class = classes[mathclass] or mathclass -- no real checks needed
+            if name == false then
+                if trace_defining then
+                    report(class,family,unicode,name)
+                end
+                setmathcharacter(class,family,unicode)
+            else
+                name = name or character.contextname
+                if name then
+                    if trace_defining then
+                        report(class,family,unicode,name)
+                    end
+                    setmathsymbol(name,class,family,unicode)
+                else
+                    if trace_defining then
+                        report(class,family,unicode,character.adobename)
+                    end
+                end
+                setmathcharacter(class,family,unicode,unicode)
+            end
+        end
+    end
+end
+
+-- needed for mathml analysis
+
+function mathematics.utfmathclass(chr, default)
+    local cd = characters.data[utfbyte(chr)]
+    return (cd and cd.mathclass) or default or "unknown"
+end
+function mathematics.utfmathstretch(chr, default) -- "h", "v", "b", ""
+    local cd = characters.data[utfbyte(chr)]
+    return (cd and cd.mathstretch) or default or ""
+end
+function mathematics.utfmathcommand(chr, default)
+    local cd = characters.data[utfbyte(chr)]
+    local cmd = cd and cd.mathname
+    tex.sprint(cmd or default or "")
+end
+function mathematics.utfmathfiller(chr, default)
+    local cd = characters.data[utfbyte(chr)]
+    local cmd = cd and (cd.mathfiller or cd.mathname)
+    tex.sprint(cmd or default or "")
+end
+
+mathematics.entities = mathematics.entities or { }
+
+function mathematics.register_xml_entities()
+    local entities = xml.entities
+    for name, unicode in pairs(mathematics.entities) do
+        if not entities[name] then
+            entities[name] = utfchar(unicode)
+        end
+    end
+end
+
+-- helpers
+
+function mathematics.big(tfmdata,unicode,n)
+    local t = tfmdata.characters
+    local c = t[unicode]
+    if c then
+        local next = c.next
+        while next do
+            if n <= 1 then
+                return next
+            else
+                n = n - 1
+                next = t[next].next
+            end
+        end
+    end
+    return unicode
+end
+
+-- plugins
+
+local hvars = table.tohash {
+    --~ "RadicalKernBeforeDegree",
+    --~ "RadicalKernAfterDegree",
+}
+
+function mathematics.scaleparameters(t,tfmtable,delta,hdelta,vdelta)
+    local math_parameters = tfmtable.math_parameters
+    if math_parameters and next(math_parameters) then
+        delta = delta or 1
+        hdelta, vdelta = hdelta or delta, vdelta or delta
+        local _, mp = mathematics.dimensions(math_parameters)
+        for name, value in next, mp do
+            if name == "RadicalDegreeBottomRaisePercent" then
+                mp[name] = value
+            elseif hvars[name] then
+                mp[name] = hdelta * value
+            else
+                mp[name] = vdelta * value
+            end
+        end
+        t.MathConstants = mp
+    end
+end
+
+table.insert(fonts.tfm.mathactions,mathematics.scaleparameters)