diff options
Diffstat (limited to 'Master/texmf-dist/tex/context/base/mkiv/typo-lan.lua')
-rw-r--r-- | Master/texmf-dist/tex/context/base/mkiv/typo-lan.lua | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/Master/texmf-dist/tex/context/base/mkiv/typo-lan.lua b/Master/texmf-dist/tex/context/base/mkiv/typo-lan.lua new file mode 100644 index 00000000000..c42d2119eb6 --- /dev/null +++ b/Master/texmf-dist/tex/context/base/mkiv/typo-lan.lua @@ -0,0 +1,74 @@ +if not modules then modules = { } end modules ['typo-lan'] = { + version = 1.001, + comment = "companion to typo-lan.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 currentfont = font.current +local setmetatableindex = table.setmetatableindex +local utfbyte = utf.byte + +local hashes = fonts.hashes +local fontdata = hashes.characters +local emwidths = hashes.emwidths + +local frequencies = languages.frequencies or { } +languages.frequencies = frequencies + +local frequencydata = { } +local frequencyfile = string.formatters["lang-frq-%s.lua"] +local frequencycache = { } + +setmetatableindex(frequencydata, function(t,language) + local fullname = resolvers.findfile(frequencyfile(language)) + local v = fullname ~= "" and dofile(fullname) + if not v or not v.frequencies then + v = t.en + end + t[language] = v + return v +end) + +setmetatableindex(frequencycache, function(t,language) + local dataset = frequencydata[language] + local frequencies = dataset.frequencies + if not frequencies then + return t.en + end + local v = { } + setmetatableindex(v, function(t,font) + local average = emwidths[font] / 2 + if frequencies then + local characters = fontdata[font] + local sum, tot = 0, 0 + for k, v in next, frequencies do + local character = characters[k] -- characters[type(k) == "number" and k or utfbyte(k)] + tot = tot + v + sum = sum + v * (character and character.width or average) + end + average = sum / tot -- widths + end + t[font] = average + return average + end) + t[language] = v + return v +end) + +function frequencies.getdata(language) + return frequencydata[language] +end + +function frequencies.averagecharwidth(language,font) + return frequencycache[language or "en"][font or currentfont()] +end + +interfaces.implement { + name = "averagecharwidth", + actions = { frequencies.averagecharwidth, context }, + arguments = "string" +} |