add glyph name <-> codepoint resolver

1 files changed, 38 insertions, 0 deletions

diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua
index a5f22dd..f7886be 100644
--- a/luaotfload-auxiliary.lua
+++ b/luaotfload-auxiliary.lua
@@ -174,6 +174,44 @@ end
 
 aux.do_if_glyph_else = do_if_glyph_else
 
+--- this one is approximately “name_to_slot” from the microtype
+--- package
+
+--- string -> (int | false)
+local codepoint_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] --- again, does that even happen?
+    end
+  end
+  return false
+end
+
+aux.codepoint_of_name = codepoint_of_name
+
+--- inverse of above
+
+local indices
+
+--- int -> (string | false)
+local name_of_codepoint = 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_codepoint = name_of_codepoint
+
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 ---                 features / scripts / languages
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