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author | Philipp Gesang <phg42.2a@gmail.com> | 2013-05-01 19:34:11 +0200 |
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committer | Philipp Gesang <phg42.2a@gmail.com> | 2013-05-01 19:34:11 +0200 |
commit | 3d757d9ac865a0751750b1b358f9fa1781d97883 (patch) | |
tree | bf1f9c4b2633dd65fc648cb3668e5adc959febd6 | |
parent | 7cf60286cb69e8b5ffc47c06bdc9a18bb941e306 (diff) | |
download | luaotfload-3d757d9ac865a0751750b1b358f9fa1781d97883.tar.gz |
add capheight callback
-rw-r--r-- | luaotfload-auxiliary.lua | 58 |
1 files changed, 55 insertions, 3 deletions
diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua index 2d55db5..01e1bc0 100644 --- a/luaotfload-auxiliary.lua +++ b/luaotfload-auxiliary.lua @@ -3,7 +3,7 @@ -- FILE: luaotfload-auxiliary.lua -- DESCRIPTION: part of luaotfload -- REQUIREMENTS: luaotfload 2.2 --- AUTHOR: Philipp Gesang (Phg), <phg42.2a@gmail.com> +-- AUTHOR: Khaled Hosny, Élie Roux, Philipp Gesang -- VERSION: 1.0 -- CREATED: 2013-05-01 14:40:50+0200 ----------------------------------------------------------------------- @@ -27,6 +27,7 @@ local utf8 = unicode.utf8 local stringlower = string.lower local stringformat = string.format local stringgsub = string.gsub +local stringbyte = string.byte ----------------------------------------------------------------------- --- font patches @@ -86,6 +87,57 @@ luatexbase.add_to_callback( 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 ----------------------------------------------------------------------- @@ -236,8 +288,8 @@ accounted for in the script with tag “asked_script” in feature --doc]]-- --- int -> string -> string -> string -> bool -local provides_feature = function(font_id, asked_script, - asked_language, asked_feature) +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) |