4 files changed, 23 insertions, 12 deletions

diff --git a/extension/src/MapSingleton.cpp b/extension/src/MapSingleton.cpp
index 982ad78..31cbd98 100644
--- a/extension/src/MapSingleton.cpp
+++ b/extension/src/MapSingleton.cpp
@@ -59,7 +59,7 @@ MapSingleton::~MapSingleton() {
 }
 
 Error MapSingleton::parse_json_dictionary_file(String const& file_description, String const& file_path,
-	String const& identifier_prefix, parse_json_entry_func_t parse_entry) {
+	String const& identifier_prefix, parse_json_entry_func_t parse_entry) const {
 	UtilityFunctions::print("Loading ", file_description, " file: ", file_path);
 	Ref<FileAccess> file = FileAccess::open(file_path, FileAccess::ModeFlags::READ);
 	Error err = FileAccess::get_open_error();
@@ -95,7 +95,7 @@ Error MapSingleton::parse_json_dictionary_file(String const& file_description, S
 		}
 		if (!identifier.begins_with(identifier_prefix))
 			UtilityFunctions::push_warning("Identifier in ", file_description, " file missing \"", identifier_prefix, "\" prefix: ", identifier);
-		if ((this->*parse_entry)(identifier, entry) != OK) err = FAILED;
+		if (parse_entry(identifier, entry) != OK) err = FAILED;
 	}
 	return err;
 }
@@ -145,8 +145,10 @@ Error MapSingleton::_parse_province_identifier_entry(String const& identifier, V
 }
 
 Error MapSingleton::load_province_identifier_file(String const& file_path) {
-	const Error err = parse_json_dictionary_file("province identifier",
-		file_path, "prov_", &MapSingleton::_parse_province_identifier_entry);
+	const Error err = parse_json_dictionary_file("province identifier", file_path, "prov_",
+		[this](String const& identifier, Variant const& entry) -> Error {
+			return this->_parse_province_identifier_entry(identifier, entry);
+		});
 	map.lock_provinces();
 	return err;
 }
@@ -178,8 +180,10 @@ Error MapSingleton::_parse_region_entry(String const& identifier, Variant const&
 }
 
 Error MapSingleton::load_region_file(String const& file_path) {
-	const Error err = parse_json_dictionary_file("region",
-		file_path, "region_", &MapSingleton::_parse_region_entry);
+	const Error err = parse_json_dictionary_file("region", file_path, "region_",
+		[this](String const& identifier, Variant const& entry) -> Error {
+			return this->_parse_region_entry(identifier, entry);
+		});
 	map.lock_regions();
 	return err;
 }
diff --git a/extension/src/MapSingleton.hpp b/extension/src/MapSingleton.hpp
index 55d2883..7d50d55 100644
--- a/extension/src/MapSingleton.hpp
+++ b/extension/src/MapSingleton.hpp
@@ -1,12 +1,14 @@
 #pragma once
 
+#include <functional>
+
 #include <godot_cpp/classes/image.hpp>
 
 #include "openvic2/Map.hpp"
 
 namespace OpenVic2 {
 	class MapSingleton : public godot::Object {
-		using parse_json_entry_func_t = godot::Error (MapSingleton::*)(godot::String const& identifier, godot::Variant const& entry);
+		using parse_json_entry_func_t = std::function<godot::Error (godot::String const&, godot::Variant const&)>;
 
 		GDCLASS(MapSingleton, godot::Object)
 
@@ -17,7 +19,7 @@ namespace OpenVic2 {
 		Mapmode::index_t mapmode_index = 0;
 
 		godot::Error parse_json_dictionary_file(godot::String const& file_description, godot::String const& file_path,
-			godot::String const& identifier_prefix, parse_json_entry_func_t parse_entry);
+			godot::String const& identifier_prefix, parse_json_entry_func_t parse_entry) const;
 		godot::Error _parse_province_identifier_entry(godot::String const& identifier, godot::Variant const& entry);
 		godot::Error _parse_region_entry(godot::String const& identifier, godot::Variant const& entry);
 	protected:
diff --git a/extension/src/openvic2/Map.cpp b/extension/src/openvic2/Map.cpp
index 921f371..1654189 100644
--- a/extension/src/openvic2/Map.cpp
+++ b/extension/src/openvic2/Map.cpp
@@ -297,7 +297,7 @@ return_t Map::generate_mapmode_colours(Mapmode::index_t index, uint8_t* target,
 	Mapmode const& mapmode = mapmodes[index];
 	target += 3; // Skip past Province::NULL_INDEX
 	for (Province const& province : provinces) {
-		const Province::colour_t colour = (*mapmode.get_colour_func())(*this, province);
+		const Province::colour_t colour = mapmode.get_colour_func()(*this, province);
 		*target++ = (colour >> 16) & 0xFF;
 		*target++ = (colour >> 8) & 0xFF;
 		*target++ = colour & 0xFF;
diff --git a/extension/src/openvic2/Map.hpp b/extension/src/openvic2/Map.hpp
index 2fa8bc8..20e8a92 100644
--- a/extension/src/openvic2/Map.hpp
+++ b/extension/src/openvic2/Map.hpp
@@ -3,16 +3,20 @@
 #include <string>
 #include <cstdint>
 #include <vector>
+#include <functional>
 
 #include "Types.hpp"
 
 namespace OpenVic2 {
 	struct Region;
+	struct Map;
 
 	struct Province {
+		friend struct Map;
+
 		using colour_t = uint32_t;
 		using index_t = uint16_t;
-		friend struct Map;
+
 		static const colour_t NULL_COLOUR = 0, MAX_COLOUR = 0xFFFFFF;
 		static const index_t NULL_INDEX = 0, MAX_INDEX = 0xFFFF;
 	private:
@@ -47,9 +51,10 @@ namespace OpenVic2 {
 	};
 
 	struct Mapmode {
-		using colour_func_t = Province::colour_t (*)(Map const& map, Province const& province);
-		using index_t = size_t;
 		friend struct Map;
+
+		using colour_func_t = std::function<Province::colour_t (Map const&, Province const&)>;
+		using index_t = size_t;
 	private:
 		index_t index;
 		std::string identifier;