1 files changed, 122 insertions, 0 deletions
diff --git a/otfl-font-enc.lua b/otfl-font-enc.lua
new file mode 100644
index 0000000..874f7c3
--- /dev/null
+++ b/otfl-font-enc.lua
@@ -0,0 +1,122 @@
+if not modules then modules = { } end modules ['font-enc'] = {
+    version   = 1.001,
+    comment   = "companion to font-ini.mkiv",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+local match, gmatch, gsub = string.match, string.gmatch, string.gsub
+
+--[[ldx--
+<p>Because encodings are going to disappear, we don't bother defining
+them in tables. But we may do so some day, for consistency.</p>
+--ldx]]--
+
+fonts.enc         = fonts.enc or { }
+fonts.enc.version = 1.03
+fonts.enc.cache   = containers.define("fonts", "enc", fonts.enc.version, true)
+
+fonts.enc.known = { -- sort of obsolete
+    texnansi = true,
+    ec       = true,
+    qx       = true,
+    t5       = true,
+    t2a      = true,
+    t2b      = true,
+    t2c      = true,
+    unicode  = true
+}
+
+function fonts.enc.is_known(encoding)
+    return containers.is_valid(fonts.enc.cache(),encoding)
+end
+
+--[[ldx--
+<p>An encoding file looks like this:</p>
+
+<typing>
+/TeXnANSIEncoding [
+/.notdef
+/Euro
+...
+/ydieresis
+] def
+</typing>
+
+<p>Beware! The generic encoding files don't always apply to the ones that
+ship with fonts. This has to do with the fact that names follow (slightly)
+different standards. However, the fonts where this applies to (for instance
+Latin Modern or <l n='tex'> Gyre) come in OpenType variants too, so these
+will be used.</p>
+--ldx]]--
+
+function fonts.enc.load(filename)
+    local name = file.removesuffix(filename)
+    local data = containers.read(fonts.enc.cache(),name)
+    if data then
+        return data
+    end
+    if name == "unicode" then
+        data = fonts.enc.make_unicode_vector() -- special case, no tex file for this
+    end
+    if data then
+        return data
+    end
+    local vector, tag, hash, unicodes = { }, "", { }, { }
+    local foundname = resolvers.find_file(filename,'enc')
+    if foundname and foundname ~= "" then
+        local ok, encoding, size = resolvers.loadbinfile(foundname)
+        if ok and encoding then
+            local enccodes = characters.enccodes
+            encoding = gsub(encoding,"%%(.-)\n","")
+            local tag, vec = match(encoding,"/(%w+)%s*%[(.*)%]%s*def")
+            local i = 0
+            for ch in gmatch(vec,"/([%a%d%.]+)") do
+                if ch ~= ".notdef" then
+                    vector[i] = ch
+                    if not hash[ch] then
+                        hash[ch] = i
+                    else
+                        -- duplicate, play safe for tex ligs and take first
+                    end
+                    if enccodes[ch] then
+                        unicodes[enccodes[ch]] = i
+                    end
+                end
+                i = i + 1
+            end
+        end
+    end
+    local data = {
+        name=name,
+        tag=tag,
+        vector=vector,
+        hash=hash,
+        unicodes=unicodes
+    }
+    return containers.write(fonts.enc.cache(), name, data)
+end
+
+--[[ldx--
+<p>There is no unicode encoding but for practical purposed we define
+one.</p>
+--ldx]]--
+
+-- maybe make this a function:
+
+function fonts.enc.make_unicode_vector()
+    local vector, hash = { }, { }
+    for code, v in next, characters.data do
+        local name = v.adobename
+        if name then
+            vector[code], hash[name] = name, code
+        else
+            vector[code] = '.notdef'
+        end
+    end
+    for name, code in next, characters.synonyms do
+        vector[code], hash[name] = name, code
+    end
+    return containers.write(fonts.enc.cache(), 'unicode', { name='unicode', tag='unicode', vector=vector, hash=hash })
+end