fix: don't try to bleed corpses that lack blood, remove rotten decay …

…results, blood dumped on the ground becomes a field (#4879)

data/json/emit.json

@@ -115,6 +115,12 @@
     "chance": 1,
     "qty": 25
   },
+  {
+    "id": "emit_drop_blood",
+    "type": "emit",
+    "field": "fd_blood",
+    "intensity": 1
+  },
   {
     "id": "emit_acid_splash",
     "type": "emit",

data/json/items/comestibles/carnivore.json

@@ -570,7 +570,8 @@
     "material": "hflesh",
     "volume": "250 ml",
     "phase": "liquid",
-    "fun": -50
+    "fun": -50,
+    "drop_action": { "type": "emit_actor", "emits": [ "emit_drop_blood" ], "scale_qty": true }
   },
   {
     "type": "COMESTIBLE",

src/game.cpp

@@ -8231,6 +8231,7 @@ static void butcher_submenu( const std::vector<item *> &corpses, int corpse = -1
     };
     const bool enough_light = character_funcs::can_see_fine_details( you );
 
+    bool has_blood = false;
     bool has_skin = false;
     bool has_organs = false;
 
@@ -8248,6 +8249,9 @@ static void butcher_submenu( const std::vector<item *> &corpses, int corpse = -1
         const mtype *dead_mon = it->get_mtype();
         if( dead_mon != nullptr ) {
             for( const harvest_entry &entry : dead_mon->harvest.obj() ) {
+                if( entry.type == "blood" ) {
+                    has_blood = true;
+                }
                 if( entry.type == "skin" ) {
                     has_skin = true;
                 }
@@ -8282,8 +8286,10 @@ static void butcher_submenu( const std::vector<item *> &corpses, int corpse = -1
                                           "(for ex. a table, a leather tarp, etc.).  "
                                           "Yields are plentiful and varied, but it is time consuming." ),
                                        msg_inv, info_on_action( BUTCHER_FULL ).c_str() ) );
-    smenu.addentry_col( BLEED, enough_light, 'l', _( "Bleed corpse" ),
-                        enough_light ? cut_time( BLEED ) : cannot_see,
+    smenu.addentry_col( BLEED, enough_light &&
+                        has_blood, 'l', _( "Bleed corpse" ),
+                        enough_light ? ( has_blood ? cut_time( BLEED ) : colorize( _( "has no blood" ),
+                                         c_red ) ) : cannot_see,
                         string_format( "%s  %s%s",
                                        _( "Bleeding involves severing the carotid arteries and jugular "
                                           "veins, or the blood vessels from which they arise.  "

src/map.cpp

@@ -7319,8 +7319,9 @@ void map::handle_decayed_corpse( const item &it, const tripoint &pnt )
                 if( harvest->charges > 1 ) {
                     harvest->charges = 1;
                 }
-
-                add_item_or_charges( pnt, item::spawn( *harvest ) );
+                if( !harvest->rotten() ) {
+                    add_item_or_charges( pnt, item::spawn( *harvest ) );
+                }
             }
         }
     }