fix time travel due to 1s turns

src/item.cpp

@@ -9389,6 +9389,17 @@ void item::set_age( const time_duration &age )
     set_birthday( time_point( calendar::turn ) - age );
 }
 
+void item::legacy_fast_forward_time()
+{
+    const time_duration tmp_bday = ( bday - calendar::turn_zero ) * 6;
+    bday = calendar::turn_zero + tmp_bday;
+
+    rot *= 6;
+
+    const time_duration tmp_rot = ( last_rot_check - calendar::turn_zero ) * 6;
+    last_rot_check = calendar::turn_zero + tmp_rot;
+}
+
 time_point item::birthday() const
 {
     return bday;

src/item.h

@@ -1953,6 +1953,7 @@ class item : public visitable<item>
 
         time_duration age() const;
         void set_age( const time_duration &age );
+        void legacy_fast_forward_time();
         time_point birthday() const;
         void set_birthday( const time_point &bday );
         void handle_pickup_ownership( Character &c );

src/mapbuffer.cpp

@@ -284,13 +284,11 @@ void mapbuffer::deserialize( JsonIn &jsin )
         std::unique_ptr<submap> sm = std::make_unique<submap>();
         tripoint submap_coordinates;
         jsin.start_object();
-        bool rubpow_update = false;
+        int version = 0;
         while( !jsin.end_object() ) {
             std::string submap_member_name = jsin.get_member_name();
             if( submap_member_name == "version" ) {
-                if( jsin.get_int() < 22 ) {
-                    rubpow_update = true;
-                }
+                version = jsin.get_int();
             } else if( submap_member_name == "coordinates" ) {
                 jsin.start_array();
                 int locx = jsin.get_int();
@@ -299,7 +297,7 @@ void mapbuffer::deserialize( JsonIn &jsin )
                 jsin.end_array();
                 submap_coordinates = tripoint( locx, locy, locz );
             } else {
-                sm->load( jsin, submap_member_name, rubpow_update );
+                sm->load( jsin, submap_member_name, version );
             }
         }
 

src/savegame.cpp

@@ -172,6 +172,11 @@ void game::unserialize( std::istream &fin )
         data.read( "calendar_start", tmpcalstart );
         calendar::initial_season = static_cast<season_type>( data.get_int( "initial_season",
                                    static_cast<int>( SPRING ) ) );
+        // 0.E stable
+        if( savegame_loading_version < 26 ) {
+            tmpturn *= 6;
+            tmpcalstart *= 6;
+        }
         data.read( "auto_travel_mode", auto_travel_mode );
         data.read( "run_mode", tmprun );
         data.read( "mostseen", mostseen );

src/savegame_json.cpp

@@ -2354,6 +2354,10 @@ void item::deserialize( JsonIn &jsin )
     const JsonObject data = jsin.get_object();
     io::JsonObjectInputArchive archive( data );
     io( archive );
+    // made for fast forwarding time from 0.D to 0.E
+    if( savegame_loading_version < 27 ) {
+        legacy_fast_forward_time();
+    }
 }
 
 void item::serialize( JsonOut &json ) const
@@ -3724,8 +3728,9 @@ void submap::store( JsonOut &jsout ) const
     }
 }
 
-void submap::load( JsonIn &jsin, const std::string &member_name, bool rubpow_update )
+void submap::load( JsonIn &jsin, const std::string &member_name, int version )
 {
+    bool rubpow_update = version < 22;
     if( member_name == "turn_last_touched" ) {
         last_touched = jsin.get_int();
     } else if( member_name == "temperature" ) {
@@ -3831,6 +3836,10 @@ void submap::load( JsonIn &jsin, const std::string &member_name, bool rubpow_upd
                     update_lum_add( p, tmp );
                 }
 
+                if( savegame_loading_version >= 27 && version < 27 ) {
+                    tmp.legacy_fast_forward_time();
+                }
+
                 tmp.visit_items( [ this, &p ]( item * it ) {
                     for( auto &e : it->magazine_convert() ) {
                         itm[p.x][p.y].insert( e );

src/submap.h

@@ -181,7 +181,7 @@ class submap : public maptile_soa<SEEX, SEEY>    // TODO: Use private inheritanc
         void rotate( int turns );
 
         void store( JsonOut &jsout ) const;
-        void load( JsonIn &jsin, const std::string &member_name, bool rubpow_update );
+        void load( JsonIn &jsin, const std::string &member_name, int version );
 
         // If is_uniform is true, this submap is a solid block of terrain
         // Uniform submaps aren't saved/loaded, because regenerating them is faster