draft for new auxlib

1 files changed, 117 insertions, 0 deletions

diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua
new file mode 100644
index 0000000..1f0c79c
--- /dev/null
+++ b/luaotfload-auxiliary.lua
@@ -0,0 +1,117 @@
+#!/usr/bin/env texlua
+-----------------------------------------------------------------------
+--         FILE:  luaotfload-auxiliary.lua
+--  DESCRIPTION:  part of luaotfload
+-- REQUIREMENTS:  luaotfload 2.2
+--       AUTHOR:  Philipp Gesang (Phg), <phg42.2a@gmail.com>
+--      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 utf8 = unicode.utf8
+
+local aux = luaotfload.aux
+
+-----------------------------------------------------------------------
+---                          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")
+
+-----------------------------------------------------------------------
+---                              fonts
+-----------------------------------------------------------------------
+
+--- 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
+
+-- vim:tw=71:sw=2:ts=2:expandtab