make font patching work again with font definition wrapper

2 files changed, 48 insertions, 19 deletions

diff --git a/luaotfload-deferred.lua b/luaotfload-deferred.lua
index bfbf644..93e8bb2 100644
--- a/luaotfload-deferred.lua
+++ b/luaotfload-deferred.lua
@@ -85,6 +85,19 @@ local define_font_wrapper = function (...)
     end
     return tfmdata
 end
+
+--[[doc--
+We provide a simplified version of the original font definition
+callback.
+--doc]]--
+local patch_defined_font = function (...)
+    local tfmdata = fonts.definers.read(...)
+    if type(tfmdata) == "table" and tfmdata.shared then
+        call_callback("luaotfload.patch_font", tfmdata)
+    end
+    return tfmdata
+end
+
 fonts.mode = "node"
 
 function attributes.private(name)
@@ -98,16 +111,21 @@ end
 
 reset_callback("define_font")
 
-if luaotfload.old_font_definer  then
+if luaotfload.font_definer == "old"  then
   add_to_callback("define_font",
                   old_define_font_wrapper,
                   "luaotfload.define_font",
                   1)
-else -- use default font loader
+elseif luaotfload.font_definer == "generic"  then
   add_to_callback("define_font",
                   generic_context.callback_define_font,
                   "luaotfload.define_font",
                   1)
+elseif luaotfload.font_definer == "patch"  then
+  add_to_callback("define_font",
+                  patch_defined_font,
+                  "luaotfload.define_font",
+                  1)
 end
 
 --luaotfload.loadmodule("font-otc.lua") -- broken
@@ -126,23 +144,27 @@ end
 --add_to_callback("find_vf_file",
                  --fonts.vf.find,
                 --"luaotfload.find_vf_file")
---local function set_sscale_diments(fontdata)
-    --local mc = fontdata.MathConstants
-    --if mc then
-        --if mc["ScriptPercentScaleDown"] then
-            --fontdata.parameters[10] = mc.ScriptPercentScaleDown
-        --else -- resort to plain TeX default
-            --fontdata.parameters[10] = 70
-        --end
-        --if mc["ScriptScriptPercentScaleDown"] then
-            --fontdata.parameters[11] = mc.ScriptScriptPercentScaleDown
-        --else -- resort to plain TeX default
-            --fontdata.parameters[11] = 50
-        --end
-    --end
---end
 
---luatexbase.add_to_callback("luaotfload.patch_font", set_sscale_diments, "unicodemath.set_sscale_diments")
+local set_sscale_diments = function (tfmdata)
+    local mathconstants = tfmdata.MathConstants
+    if mathconstants then
+        local tfmparameters = tfmdata.parameters
+        if mathconstants.ScriptPercentScaleDown then
+            tfmparameters[10] = mathconstants.ScriptPercentScaleDown
+        else -- resort to plain TeX default
+            tfmparameters[10] = 70
+        end
+        if mathconstants.ScriptScriptPercentScaleDown then
+            tfmparameters[11] = mathconstants.ScriptScriptPercentScaleDown
+        else -- resort to plain TeX default
+            tfmparameters[11] = 50
+        end
+    end
+end
+
+add_to_callback("luaotfload.patch_font",
+                set_sscale_diments,
+                "unicodemath.set_sscale_diments")
 
 -- vim:tw=71:sw=2:ts=2:expandtab
 
diff --git a/luaotfload.lua b/luaotfload.lua
index 1bfca79..0a3b398 100644
--- a/luaotfload.lua
+++ b/luaotfload.lua
@@ -29,7 +29,14 @@ luaotfload.module = {
     license       = "CC0"
 }
 
-luaotfload.old_font_definer = false --- toggle wrapper for font loader
+--[[doc--
+No final decision has been made on how to handle font definition.
+At the moment, there are three candidates: The \textsf{generic}
+callback as hard-coded in the font loader, the \textsf{old} wrapper,
+and a simplified version of the latter (\textsf{patch}) that does
+nothing besides applying font patches.
+--doc]]--
+luaotfload.font_definer = "patch" --- | “generic” | “old”
 
 local fl_prefix = "otfl" -- “luatex” for luatex-plain