Use find_point_closest_first where appropriate.

src/activity_item_handling.cpp

@@ -3561,8 +3561,7 @@ int get_auto_consume_moves( Character &you, const bool food )
 bool try_fuel_fire( player_activity &act, Character &you, const bool starting_fire )
 {
     const tripoint_bub_ms pos = you.pos_bub();
-    std::vector<tripoint_bub_ms> adjacent = closest_points_first( pos, PICKUP_RANGE );
-    adjacent.erase( adjacent.begin() );
+    std::vector<tripoint_bub_ms> adjacent = closest_points_first( pos, 1, PICKUP_RANGE );
 
     map &here = get_map();
     std::optional<tripoint_bub_ms> best_fire =

src/map.cpp

@@ -5619,8 +5619,7 @@ std::pair<item *, tripoint_bub_ms> map::_add_item_or_charges( const tripoint_bub
     if( overflow && copies_remaining > 0 ) {
         // ...otherwise try to overflow to adjacent tiles (if permitted)
         const int max_dist = 2;
-        std::vector<tripoint_bub_ms> tiles = closest_points_first( pos, max_dist );
-        tiles.erase( tiles.begin() ); // we already tried this position
+        std::vector<tripoint_bub_ms> tiles = closest_points_first( pos, 1, max_dist );
         const int max_path_length = 4 * max_dist;
         const pathfinding_settings setting( 0, max_dist, max_path_length, 0, false, false, true, false,
                                             false, false );

src/monattack.cpp

@@ -2234,9 +2234,7 @@ bool mattack::formblob( monster *z )
     }
 
     bool didit = false;
-    std::vector<tripoint> pts = closest_points_first( z->pos(), 1 );
-    // Don't check own tile
-    pts.erase( pts.begin() );
+    std::vector<tripoint> pts = closest_points_first( z->pos(), 1, 1 );
     creature_tracker &creatures = get_creature_tracker();
     for( const tripoint &dest : pts ) {
         Creature *critter = creatures.creature_at( dest );
@@ -4765,4 +4763,4 @@ bool mattack::speaker( monster *z )
     sounds::sound( z->pos(), 60, sounds::sound_t::order,
                    SNIPPET.random_from_category( "speaker_warning" ).value_or( translation() ) );
     return true;
-}
+}

src/monmove.cpp

@@ -1774,11 +1774,17 @@ bool monster::attack_at( const tripoint &p )
 
 static tripoint find_closest_stair( const tripoint &near_this, const ter_furn_flag stair_type )
 {
-    map &here = get_map();
-    for( const tripoint &candidate : closest_points_first( near_this, 10 ) ) {
+    const map &here = get_map();
+    std::optional<tripoint> candidate = find_point_closest_first( near_this, 10, [&here,
+    stair_type]( const tripoint & candidate ) {
         if( here.has_flag( stair_type, candidate ) ) {
-            return candidate;
+            return true;
         }
+    }
+                                                                );
+
+    if( candidate != std::nullopt ) {
+        return *candidate;
     }
     // we didn't find it
     return near_this;

src/npc.cpp

@@ -1045,7 +1045,7 @@ void npc::place_on_map()
         return;
     }
 
-    for( const tripoint &p : closest_points_first( pos(), SEEX + 1 ) ) {
+    for( const tripoint &p : closest_points_first( pos(), 1, SEEX + 1 ) ) {
         if( g->is_empty( p ) ) {
             setpos( p );
             return;

src/npcmove.cpp

@@ -3176,8 +3176,7 @@ void npc::avoid_friendly_fire()
     center.y = std::round( center.y / friend_count );
     center.z = std::round( center.z / friend_count );
 
-    std::vector<tripoint> candidates = closest_points_first( pos(), 1 );
-    candidates.erase( candidates.begin() );
+    std::vector<tripoint> candidates = closest_points_first( pos(), 1, 1 );
     std::sort( candidates.begin(), candidates.end(),
     [&tar, &center]( const tripoint & l, const tripoint & r ) {
         return ( rl_dist( l, tar ) - rl_dist( l, center ) ) <

src/ranged.cpp

@@ -2235,11 +2235,14 @@ static void cycle_action( item &weap, const itype_id &ammo, const tripoint &pos
 {
     map &here = get_map();
     // eject casings and linkages in random direction avoiding walls using player position as fallback
-    std::vector<tripoint> tiles = closest_points_first( pos, 1 );
-    tiles.erase( tiles.begin() );
-    tiles.erase( std::remove_if( tiles.begin(), tiles.end(), [&]( const tripoint & e ) {
-        return !here.passable( e );
-    } ), tiles.end() );
+    std::vector<tripoint> tiles;
+    tiles.reserve( 8 );
+    find_point_closest_first( pos, 1, 1, [&here, &tiles]( const tripoint & e ) {
+        if( here.passable( e ) ) {
+            tiles.push_back( e );
+        }
+        return false;
+    } );
     tripoint eject = tiles.empty() ? pos : random_entry( tiles );
 
     // for turrets try and drop casings or linkages directly to any CARGO part on the same tile
@@ -3161,12 +3164,12 @@ tripoint target_ui::choose_initial_target()
 
     // Try closest practice target
     map &here = get_map();
-    const std::vector<tripoint> nearby = closest_points_first( src, range );
-    const auto target_spot = std::find_if( nearby.begin(), nearby.end(),
-    [this, &here]( const tripoint & pt ) {
+    const std::optional<tripoint> target_spot = find_point_closest_first( src, range, [this,
+    &here]( const tripoint & pt ) {
         return here.tr_at( pt ).id == tr_practice_target && this->you->sees( pt );
     } );
-    if( target_spot != nearby.end() ) {
+
+    if( target_spot != std::nullopt ) {
         return *target_spot;
     }
 

src/vehicle.cpp

@@ -7666,10 +7666,14 @@ void vehicle::leak_fuel( vehicle_part &pt ) const
 
     map &here = get_map();
     // leak in random directions but prefer closest tiles and avoid walls or other obstacles
-    std::vector<tripoint> tiles = closest_points_first( global_part_pos3( pt ), 1 );
-    tiles.erase( std::remove_if( tiles.begin(), tiles.end(), [&here]( const tripoint & e ) {
-        return !here.passable( e );
-    } ), tiles.end() );
+    std::vector<tripoint> tiles;
+    tiles.reserve( 9 );
+    find_point_closest_first( global_part_pos3( pt ), 1, [&here, &tiles]( const tripoint & e ) {
+        if( here.passable( e ) ) {
+            tiles.push_back( e );
+        }
+        return false;
+    } );
 
     // leak up to 1/3 of remaining fuel per iteration and continue until the part is empty
     const itype *fuel = item::find_type( pt.ammo_current() );