libworld: expose WorldInfo::fog value to lua

src/logic/scripting/lua/libs/libworld.cpp

@@ -62,6 +62,15 @@ static int l_set_day_time(lua::State* L) {
     require_world_info().daytime = std::fmod(value, 1.0);
     return 0;
 }
+static int l_get_fog(lua::State* L) {
+    return lua::pushnumber(L, require_world_info().fog);
+}
+
+static int l_set_fog(lua::State* L) {
+    auto value = lua::tonumber(L, 1);
+    require_world_info().fog = std::fmod(value, 1.0);
+    return 0;
+}
 
 static int l_set_day_time_speed(lua::State* L) {
     auto value = lua::tonumber(L, 1);
@@ -102,6 +111,8 @@ const luaL_Reg worldlib[] = {
     {"get_total_time", lua::wrap<l_get_total_time>},
     {"get_day_time", lua::wrap<l_get_day_time>},
     {"set_day_time", lua::wrap<l_set_day_time>},
+    {"get_fog", lua::wrap<l_get_fog>},
+    {"set_fog", lua::wrap<l_set_fog>},
     {"set_day_time_speed", lua::wrap<l_set_day_time_speed>},
     {"get_day_time_speed", lua::wrap<l_get_day_time_speed>},
     {"get_seed", lua::wrap<l_get_seed>},