1 files changed, 92 insertions, 2 deletions

diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua
index 64fac90..2bfcbf0 100644
--- a/luaotfload-auxiliary.lua
+++ b/luaotfload-auxiliary.lua
@@ -21,11 +21,15 @@ config.luaotfload           = config.luaotfload or { }
 local aux           = luaotfload.aux
 local log           = luaotfload.log
 local warning       = luaotfload.log
-local identifiers   = fonts.hashes.identifiers
+local fonthashes    = fonts.hashes
+local identifiers   = fonthashes.identifiers
 
 local fontid        = font.id
 local texsprint     = tex.sprint
 
+local dofile        = dofile
+local getmetatable  = getmetatable
+local setmetatable  = setmetatable
 local utf8          = unicode.utf8
 local stringlower   = string.lower
 local stringformat  = string.format
@@ -227,7 +231,7 @@ luatexbase.add_to_callback(
   "luaotfload.aux.set_capheight")
 
 -----------------------------------------------------------------------
----                             glyphs
+---                      glyphs and characters
 -----------------------------------------------------------------------
 
 local agl = fonts.encodings.agl
@@ -321,6 +325,43 @@ end
 
 aux.name_of_slot      = name_of_slot
 
+--[[doc--
+
+  In Context, characters.data is where the data from char-def.lua
+  resides. The file is huge (>3.7 MB as of 2013) and not part of the
+  isolated font loader. Nevertheless, we include a partial version
+  generated by the mkcharacters script that contains only the
+  “direction” and “mirror” fields of each character defined.
+
+--doc]]--
+
+characters      = characters or { } --- should be created in basics-gen
+characters.data = { }
+local chardef   = "luaotfload-characters"
+
+do
+  local chardata
+  local index = function (t, k)
+    if chardata == nil then
+      log("Loading character metadata from %s.", chardef)
+      chardata = dofile(kpse.find_file("luaotfload-characters.lua"))
+      if chardata == nil then
+        warning("Could not load %s; continuing with empty character table.",
+                chardef)
+        chardata = { }
+      end
+    end
+    return chardata[k]
+  end
+
+  local mt = getmetatable(characters.data)
+  if mt then
+    mt.__index = index
+  else
+    setmetatable(characters.data, { __index = index })
+  end
+end
+
 -----------------------------------------------------------------------
 ---                 features / scripts / languages
 -----------------------------------------------------------------------
@@ -640,4 +681,53 @@ end
 
 aux.get_raw_fonts = get_raw_fonts
 
+-----------------------------------------------------------------------
+---                         font parameters
+-----------------------------------------------------------------------
+--- analogy of font-hsh
+
+fonthashes.parameters    = fonthashes.parameters or { }
+fonthashes.quads         = fonthashes.quads or { }
+
+local parameters         = fonthashes.parameters or { }
+local quads              = fonthashes.quads or { }
+
+setmetatable(parameters, { __index = function (t, font_id)
+  local tfmdata = identifiers[font_id]
+  if not tfmdata then --- unsafe; avoid
+    tfmdata = font.fonts[font_id]
+  end
+  if tfmdata and type(tfmdata) == "table" then
+    local fontparameters = tfmdata.parameters
+    t[font_id] = fontparameters
+    return fontparameters
+  end
+  return nil
+end})
+
+--[[doc--
+
+  Note that the reason as to why we prefer functions over table indices
+  is that functions are much safer against unintended manipulation.
+  This justifies the overhead they cost.
+
+--doc]]--
+
+--- int -> (number | false)
+local get_quad = function (font_id)
+  local quad = quads[font_id]
+  if quad then
+    return quad
+  end
+  local fontparameters = parameters[font_id]
+  if fontparameters then
+    local quad     = fontparameters.quad or 0
+    quads[font_id] = quad
+    return quad
+  end
+  return false
+end
+
+aux.get_quad = get_quad
+
 -- vim:tw=71:sw=2:ts=2:expandtab