Partially encapsulate itm

src/map.cpp

@@ -3901,7 +3901,7 @@ map_stack map::i_at( const tripoint &p )
     point l;
     submap *const current_submap = get_submap_at( p, l );
 
-    return map_stack{ &current_submap->itm[l.x][l.y], p, this };
+    return map_stack{ &current_submap->get_items( l ), p, this };
 }
 
 map_stack::iterator map::i_rem( const tripoint &p, map_stack::const_iterator it )
@@ -3917,7 +3917,7 @@ map_stack::iterator map::i_rem( const tripoint &p, map_stack::const_iterator it
 
     current_submap->update_lum_rem( l, *it );
 
-    return current_submap->itm[l.x][l.y].erase( it );
+    return current_submap->get_items( l ).erase( it );
 }
 
 void map::i_rem( const tripoint &p, item *it )
@@ -3934,7 +3934,7 @@ void map::i_clear( const tripoint &p )
     point l;
     submap *const current_submap = get_submap_at( p, l );
 
-    for( item &it : current_submap->itm[l.x][l.y] ) {
+    for( item &it : current_submap->get_items( l ) ) {
         // remove from the active items cache (if it isn't there does nothing)
         current_submap->active_items.remove( &it );
     }
@@ -3943,7 +3943,7 @@ void map::i_clear( const tripoint &p )
     }
 
     current_submap->set_lum( l, 0 );
-    current_submap->itm[l.x][l.y].clear();
+    current_submap->get_items( l ).clear();
 }
 
 item &map::spawn_an_item( const tripoint &p, item new_item,
@@ -4171,7 +4171,7 @@ item &map::add_item( const tripoint &p, item new_item )
     current_submap->is_uniform = false;
     current_submap->update_lum_add( l, new_item );
 
-    const map_stack::iterator new_pos = current_submap->itm[l.x][l.y].insert( new_item );
+    const map_stack::iterator new_pos = current_submap->get_items( l ).insert( new_item );
     if( new_item.needs_processing() ) {
         if( current_submap->active_items.empty() ) {
             submaps_with_active_items.insert( tripoint( abs_sub.x + p.x / SEEX, abs_sub.y + p.y / SEEY, p.z ) );
@@ -4233,7 +4233,7 @@ void map::make_active( item_location &loc )
     }
     point l;
     submap *const current_submap = get_submap_at( loc.position(), l );
-    cata::colony<item> &item_stack = current_submap->itm[l.x][l.y];
+    cata::colony<item> &item_stack = current_submap->get_items( l );
     cata::colony<item>::iterator iter = item_stack.get_iterator_from_pointer( target );
 
     if( current_submap->active_items.empty() ) {
@@ -4600,7 +4600,7 @@ bool map::has_items( const tripoint &p ) const
     point l;
     submap *const current_submap = get_submap_at( p, l );
 
-    return !current_submap->itm[l.x][l.y].empty();
+    return !current_submap->get_items( l ).empty();
 }
 
 template <typename Stack>
@@ -7035,7 +7035,7 @@ void map::actualize( const tripoint &grid )
             }
             // plants contain a seed item which must not be removed under any circumstances
             if( !furn.has_flag( "DONT_REMOVE_ROTTEN" ) ) {
-                remove_rotten_items( tmpsub->itm[x][y], pnt );
+                remove_rotten_items( tmpsub->get_items( { x, y } ), pnt );
             }
 
             const auto trap_here = tmpsub->get_trap( p );

src/submap.h

@@ -149,6 +149,14 @@ class submap : public maptile_soa<SEEX, SEEY>    // TODO: Use private inheritanc
             }
         }
 
+        cata::colony<item> &get_items( const point &p ) {
+            return itm[p.x][p.y];
+        }
+
+        const cata::colony<item> &get_items( const point &p ) const {
+            return itm[p.x][p.y];
+        }
+
         struct cosmetic_t {
             point pos;
             std::string type;
@@ -314,12 +322,12 @@ struct maptile {
 
         // For map::draw_maptile
         size_t get_item_count() const {
-            return sm->itm[x][y].size();
+            return sm->get_items( pos() ).size();
         }
 
         // Assumes there is at least one item
         const item &get_uppermost_item() const {
-            return *std::prev( sm->itm[x][y].cend() );
+            return *std::prev( sm->get_items( pos() ).cend() );
         }
 };
 

src/visitable.cpp

@@ -657,9 +657,9 @@ std::list<item> visitable<map_cursor>::remove_items_with( const
     // fetch the appropriate item stack
     point offset;
     submap *sub = g->m.get_submap_at( *cur, offset );
+    cata::colony<item> &stack = sub->get_items( offset );
 
-    for( auto iter = sub->itm[ offset.x ][ offset.y ].begin();
-         iter != sub->itm[ offset.x ][ offset.y ].end(); ) {
+    for( auto iter = stack.begin(); iter != stack.end(); ) {
         if( filter( *iter ) ) {
             // remove from the active items cache (if it isn't there does nothing)
             sub->active_items.remove( &*iter );
@@ -669,7 +669,7 @@ std::list<item> visitable<map_cursor>::remove_items_with( const
 
             // finally remove the item
             res.push_back( *iter );
-            iter = sub->itm[ offset.x ][ offset.y ].erase( iter );
+            iter = stack.erase( iter );
 
             if( --count == 0 ) {
                 return res;