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Diffstat (limited to 'luaotfload-auxiliary.lua')
| -rw-r--r-- | luaotfload-auxiliary.lua | 406 |
1 files changed, 406 insertions, 0 deletions
diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua new file mode 100644 index 0000000..2cf1e00 --- /dev/null +++ b/luaotfload-auxiliary.lua @@ -0,0 +1,406 @@ +#!/usr/bin/env texlua +----------------------------------------------------------------------- +-- FILE: luaotfload-auxiliary.lua +-- DESCRIPTION: part of luaotfload +-- REQUIREMENTS: luaotfload 2.2 +-- AUTHOR: Khaled Hosny, Élie Roux, Philipp Gesang +-- VERSION: 1.0 +-- CREATED: 2013-05-01 14:40:50+0200 +----------------------------------------------------------------------- +-- + +--- this file addresses issue #24 +--- https://github.com/lualatex/luaotfload/issues/24# + +luaotfload = luaotfload or {} +luaotfload.aux = luaotfload.aux or { } + +config = config or { } +config.luaotfload = config.luaotfload or { } + +local aux = luaotfload.aux +local log = luaotfload.log +local identifiers = fonts.hashes.identifiers + +local fontid = font.id +local texsprint = tex.sprint + +local utf8 = unicode.utf8 +local stringlower = string.lower +local stringformat = string.format +local stringgsub = string.gsub +local stringbyte = string.byte + +----------------------------------------------------------------------- +--- font patches +----------------------------------------------------------------------- + +--[[doc-- +This sets two dimensions apparently relied upon by the unicode-math +package. +--doc]]-- + +local set_sscale_dimens = function (fontdata) + local mathconstants = fontdata.MathConstants + local parameters = fontdata.parameters + if mathconstants then + parameters[10] = mathconstants.ScriptPercentScaleDown or 70 + parameters[11] = mathconstants.ScriptScriptPercentScaleDown or 50 + end + return fontdata +end + +luatexbase.add_to_callback( + "luaotfload.patch_font", + set_sscale_dimens, + "luaotfload.aux.set_sscale_dimens") + +--- fontobj -> int +local lookup_units = function (fontdata) + local metadata = fontdata.shared and fontdata.shared.rawdata.metadata + if metadata and metadata.units_per_em then + return metadata.units_per_em + elseif fontdata.parameters and fontdata.parameters.units then + return fontdata.parameters.units + elseif fontdata.units then --- v1.x + return fontdata.units + end + return 1000 +end + +--[[doc-- +This callback corrects some values of the Cambria font. +--doc]]-- +local patch_cambria_domh = function (fontdata) + local mathconstants = fontdata.MathConstants + if mathconstants and fontdata.psname == "CambriaMath" then + --- my test Cambria has 2048 + local units_per_em = fontdata.units_per_em or lookup_units(fontdata) + local sz = fontdata.parameters.size or fontdata.size + local mh = 2800 / units_per_em * sz + if mathconstants.DisplayOperatorMinHeight < mh then + mathconstants.DisplayOperatorMinHeight = mh + end + end +end + +luatexbase.add_to_callback( + "luaotfload.patch_font", + patch_cambria_domh, + "luaotfload.aux.patch_cambria_domh") + +--[[doc-- + +Comment from fontspec: + + “Here we patch fonts tfm table to emulate \XeTeX's \cs{fontdimen8}, + which stores the caps-height of the font. (Cf.\ \cs{fontdimen5} which + stores the x-height.) + + Falls back to measuring the glyph if the font doesn't contain the + necessary information. + This needs to be extended for fonts that don't contain an `X'.” + +--doc]]-- + +local set_capheight = function (fontdata) + local shared = fontdata.shared + local parameters = fontdata.parameters + local capheight + if shared then + local units_per_em = parameters.units + local size = parameters.size + local os2_capheight = shared.rawdata.metadata.pfminfo.os2_capheight + + if os2_capheight > 0 then + capheight = os2_capheight / units_per_em * size + else + local X8 = stringbyte"X" + if fontdata.characters[X8] then + capheight = fontdata.characters[X8].height + else + capheight = parameters.ascender / units_per_em * size + end + end + else + local X8 = stringbyte"X" + if fontdata.characters[X8] then + capheight = fontdata.characters[X8].height + end + end + if capheight then + --- is this legit? afaics there’s nothing else on the + --- array part of that table + fontdata.parameters[8] = capheight + end +end + +luatexbase.add_to_callback( + "luaotfload.patch_font", + set_capheight, + "luaotfload.aux.set_capheight") + +----------------------------------------------------------------------- +--- glyphs +----------------------------------------------------------------------- + +--- int -> int -> bool +local font_has_glyph = function (font_id, codepoint) + local fontdata = fonts.hashes.identifiers[font_id] + if fontdata then + if fontdata.characters[codepoint] ~= nil then return true end + end + return false +end + +aux.font_has_glyph = font_has_glyph + +--- int -> bool +local current_font_has_glyph = function (codepoint) + return font_has_glyph (font.current(), codepoint) +end + +aux.current_font_has_glyph = current_font_has_glyph + +local do_if_glyph_else = function (chr, positive, negative) + local codepoint = tonumber(chr) + if not codepoint then codepoint = utf8.byte(chr) end + if current_font_has_glyph(codepoint) then + tex.sprint(positive) + else + tex.sprint(negative) + end +end + +aux.do_if_glyph_else = do_if_glyph_else + +--[[doc-- + + This one is approximately “name_to_slot” from the microtype package; + note that it is all about Adobe Glyph names and glyph slots in the + font. The names and values may diverge from actual Unicode. + + http://www.adobe.com/devnet/opentype/archives/glyph.html + +--doc]]-- + +--- string -> (int | false) +local slot_of_name = function (glyphname) + local fontdata = identifiers[font.current()] + if fontdata then + local unicode = fontdata.resources.unicodes[glyphname] + if unicode and type(unicode) == "number" then + return unicode + else + return unicode[1] --- for multiple components + end + end + return false +end + +aux.slot_of_name = slot_of_name + +--[[doc-- + + Inverse of above; not authoritative as to my knowledge the official + inverse of the AGL is the AGLFN. Maybe this whole issue should be + dealt with in a separate package that loads char-def.lua and thereby + solves the problem for the next couple decades. + + http://partners.adobe.com/public/developer/en/opentype/aglfn13.txt + +--doc]]-- + +local indices + +--- int -> (string | false) +local name_of_slot = function (codepoint) + if not indices then --- this will load the glyph list + local unicodes = fonts.encodings.agl.unicodes + indices = table.swapped(unicodes) + end + local glyphname = indices[codepoint] + if glyphname then + return glyphname + end + return false +end + +aux.name_of_slot = name_of_slot + +----------------------------------------------------------------------- +--- features / scripts / languages +----------------------------------------------------------------------- +--- lots of arrowcode ahead + +--[[doc-- +This function, modeled after “check_script()” from fontspec, returns +true if in the given font, the script “asked_script” is accounted for in at +least one feature. +--doc]]-- + +--- int -> string -> bool +local provides_script = function (font_id, asked_script) + asked_script = stringlower(asked_script) + if font_id and font_id > 0 then + local fontdata = identifiers[font_id].shared.rawdata + if fontdata then + local fontname = fontdata.metadata.fontname + local features = fontdata.resources.features + for method, featuredata in next, features do + --- where method: "gpos" | "gsub" + for feature, data in next, featuredata do + if data[asked_script] then + log(stringformat( + "font no %d (%s) defines feature %s for script %s", + font_id, fontname, feature, asked_script)) + return true + end + end + end + log(stringformat( + "font no %d (%s) defines no feature for script %s", + font_id, fontname, asked_script)) + end + end + log(stringformat("no font with id %d", font_id)) + return false +end + +aux.provides_script = provides_script + +--[[doc-- +This function, modeled after “check_language()” from fontspec, returns +true if in the given font, the language with tage “asked_language” is +accounted for in the script with tag “asked_script” in at least one +feature. +--doc]]-- + +--- int -> string -> string -> bool +local provides_language = function (font_id, asked_script, asked_language) + asked_script = stringlower(asked_script) + asked_language = stringlower(asked_language) + if font_id and font_id > 0 then + local fontdata = identifiers[font_id].shared.rawdata + if fontdata then + local fontname = fontdata.metadata.fontname + local features = fontdata.resources.features + for method, featuredata in next, features do + --- where method: "gpos" | "gsub" + for feature, data in next, featuredata do + local scriptdata = data[asked_script] + if scriptdata and scriptdata[asked_language] then + log(stringformat("font no %d (%s) defines feature %s " + .. "for script %s with language %s", + font_id, fontname, feature, + asked_script, asked_language)) + return true + end + end + end + log(stringformat( + "font no %d (%s) defines no feature for script %s with language %s", + font_id, fontname, asked_script, asked_language)) + end + end + log(stringformat("no font with id %d", font_id)) + return false +end + +aux.provides_language = provides_language + +--[[doc-- +We strip the syntax elements from feature definitions (shouldn’t +actually be there in the first place, but who cares ...) +--doc]]-- + +local lpeg = require"lpeg" +local C, P, S = lpeg.C, lpeg.P, lpeg.S +local lpegmatch = lpeg.match + +local sign = S"+-" +local rhs = P"=" * P(1)^0 * P(-1) +local strip_garbage = sign^-1 * C((1 - rhs)^1) + +--s = "+foo" --> foo +--ss = "-bar" --> bar +--sss = "baz" --> baz +--t = "foo=bar" --> foo +--tt = "+bar=baz" --> bar +--ttt = "-baz=true" --> baz +-- +--print(lpeg.match(strip_garbage, s)) +--print(lpeg.match(strip_garbage, ss)) +--print(lpeg.match(strip_garbage, sss)) +--print(lpeg.match(strip_garbage, t)) +--print(lpeg.match(strip_garbage, tt)) +--print(lpeg.match(strip_garbage, ttt)) + +--[[doc-- +This function, modeled after “check_feature()” from fontspec, returns +true if in the given font, the language with tag “asked_language” is +accounted for in the script with tag “asked_script” in feature +“asked_feature”. +--doc]]-- + +--- int -> string -> string -> string -> bool +local provides_feature = function (font_id, asked_script, + asked_language, asked_feature) + asked_script = stringlower(asked_script) + asked_language = stringlower(asked_language) + asked_feature = lpegmatch(strip_garbage, asked_feature) + + if font_id and font_id > 0 then + local fontdata = identifiers[font_id].shared.rawdata + if fontdata then + local features = fontdata.resources.features + local fontname = fontdata.metadata.fontname + for method, featuredata in next, features do + --- where method: "gpos" | "gsub" + local feature = featuredata[asked_feature] + if feature then + local scriptdata = feature[asked_script] + if scriptdata and scriptdata[asked_language] then + log(stringformat("font no %d (%s) defines feature %s " + .. "for script %s with language %s", + font_id, fontname, asked_feature, + asked_script, asked_language)) + return true + end + end + end + log(stringformat( + "font no %d (%s) does not define feature %s for script %s with language %s", + font_id, fontname, asked_feature, asked_script, asked_language)) + end + end + log(stringformat("no font with id %d", font_id)) + return false +end + +aux.provides_feature = provides_feature + +----------------------------------------------------------------------- +--- font dimensions +----------------------------------------------------------------------- + +--- string -> string -> int +local get_math_dimension = function (csname, dimenname) + local fontdata = identifiers[fontid(csname)] + local mathdata = fontdata.mathparameters + if mathdata then return mathdata[dimenname] or 0 end + return 0 +end + +aux.get_math_dimension = get_math_dimension + +--- string -> string -> unit +local sprint_math_dimension = function (csname, dimenname) + local dim = get_math_dimension(csname, dimenname) + texsprint(luatexbase.catcodetables["latex-package"], dim) + texsprint(luatexbase.catcodetables["latex-package"], "sp") +end + +aux.sprint_math_dimension = sprint_math_dimension + +-- vim:tw=71:sw=2:ts=2:expandtab |