Towing vehicles

data/json/item_actions.json

@@ -309,6 +309,11 @@
     "id": "CABLE_ATTACH",
     "name": { "str": "Attach" }
   },
+  {
+    "type": "item_action",
+    "id": "TOW_ATTACH",
+    "name": { "str": "Attach" }
+  },
   {
     "type": "item_action",
     "id": "CAMERA",

data/json/itemgroups/Locations_MapExtras/locations.json

@@ -365,6 +365,7 @@
       [ "heavy_flashlight", 10 ],
       [ "jumper_cable", 20 ],
       [ "jumper_cable_heavy", 10 ],
+      [ "hd_tow_cable", 5 ],
       [ "pliers", 10 ],
       [ "battery_motorbike", 10 ],
       [ "battery_car", 10 ],
@@ -1321,6 +1322,7 @@
       [ "saddle", 8 ],
       [ "wheel", 10 ],
       [ "wheel_wide", 10 ],
+      [ "hd_tow_cable", 2 ],
       [ "wheel_bicycle", 10 ],
       [ "wheel_motorbike", 10 ],
       [ "wheel_small", 10 ],

data/json/itemgroups/supplies.json

@@ -358,6 +358,7 @@
       [ "jumper_cable_heavy", 5 ],
       [ "stereo", 25 ],
       [ "frame", 20 ],
+      [ "hd_tow_cable", 5 ],
       [ "hdframe", 10 ],
       [ "motor", 2 ],
       [ "wheel", 10 ],
@@ -395,6 +396,7 @@
       [ "alternator_car", 6 ],
       [ "alternator_truck", 6 ],
       [ "alternator_bicycle", 4 ],
+      [ "hd_tow_cable", 1 ],
       [ "generator_7500w", 3 ],
       [ "storage_battery", 6 ],
       [ "motor_oil", 100 ],

data/json/itemgroups/tools.json

@@ -53,6 +53,7 @@
       [ "xacto", 40 ],
       [ "bucket", 5 ],
       [ "jumper_cable", 10 ],
+      [ "hd_tow_cable", 5 ],
       [ "funnel", 50 ],
       [ "claw_bar", 2 ],
       [ "crowbar", 10 ],

data/json/itemgroups/vehicles_fuel_related.json

@@ -32,6 +32,7 @@
       { "item": "duct_tape", "prob": 13, "charges-min": 20, "charges-max": 200 },
       [ "screwdriver", 8 ],
       [ "screwdriver_set", 2 ],
+      [ "hd_tow_cable", 5 ],
       [ "toolbox", 1 ]
     ]
   },

data/json/items/vehicle/cables.json

@@ -18,6 +18,25 @@
     "use_action": "CABLE_ATTACH",
     "flags": [ "CABLE_SPOOL" ]
   },
+  {
+    "type": "TOOL",
+    "id": "hd_tow_cable",
+    "name": "heavy duty tow cable",
+    "description": "An extremely heavy duty tow cable made from thick steel wire.  If attached to a vehicle, it could be used to pull another vehicle of any weight.",
+    "to_hit": -1,
+    "color": "light_blue",
+    "symbol": "&",
+    "material": [ "steel", "plastic" ],
+    "volume": "3000 ml",
+    "weight": "24000 g",
+    "bashing": 6,
+    "category": "tools",
+    "price": 80,
+    "max_charges": 6,
+    "initial_charges": 6,
+    "use_action": "TOW_ATTACH",
+    "flags": [ "CABLE_SPOOL", "TOW_CABLE" ]
+  },
   {
     "type": "TOOL",
     "id": "jumper_cable_heavy",

data/json/recipes/recipe_vehicle.json

@@ -71,6 +71,19 @@
       [ [ "rope_superior_short", 2, "LIST" ] ]
     ]
   },
+  {
+    "result": "hd_tow_cable",
+    "type": "recipe",
+    "category": "CC_OTHER",
+    "subcategory": "CSC_OTHER_VEHICLE",
+    "skill_used": "fabrication",
+    "difficulty": 2,
+    "time": "480 m",
+    "autolearn": true,
+    "qualities": [ { "id": "HAMMER", "level": 1 } ],
+    "using": [ [ "welding_standard", 8 ] ],
+    "components": [ [ [ "duct_tape", 50 ] ], [ [ "grip_hook", 1 ] ], [ [ "chain", 8 ] ], [ [ "cable", 10 ] ] ]
+  },
   {
     "result": "bike_rack",
     "type": "recipe",

data/json/vehicleparts/vehicle_parts.json

@@ -2949,6 +2949,22 @@
     "flags": [ "NOINSTALL", "UNMOUNT_ON_DAMAGE", "UNMOUNT_ON_MOVE", "POWER_TRANSFER" ],
     "breaks_into": [ { "item": "wire", "count": [ 4, 8 ] }, { "item": "plastic_chunk", "count": [ 4, 8 ] } ]
   },
+  {
+    "type": "vehicle_part",
+    "id": "hd_tow_cable",
+    "name": "heavy duty tow cable",
+    "symbol": "{",
+    "color": "light_blue",
+    "broken_symbol": "*",
+    "broken_color": "dark_gray",
+    "damage_modifier": 10,
+    "durability": 120,
+    "description": "A heavy duty tow cable, if the other end was attached to another vehicle, it could pull it.",
+    "item": "hd_tow_cable",
+    "requirements": { "removal": { "time": 500 } },
+    "flags": [ "NOINSTALL", "UNMOUNT_ON_DAMAGE", "TOW_CABLE" ],
+    "breaks_into": [ { "item": "scrap", "count": [ 4, 8 ] }, { "item": "grip_hook", "count": 1 }, { "item": "cable", "count": [ 1, 4 ] } ]
+  },
   {
     "type": "vehicle_part",
     "id": "jumper_cable_debug",

doc/JSON_FLAGS.md

@@ -391,6 +391,7 @@ Some armor flags, such as `WATCH` and `ALARMCLOCK` are compatible with other ite
 - ```TORCH``` Light a torch.
 - ```TOURISTMAP``` Learn of local points-of-interest that a tourist would like to visit, and show roads.
 - ```TOWEL``` Dry your character using the item as towel.
+- ```TOW_ATTACH``` This is a tow cable, activate it to attach it to a vehicle.
 - ```TURRET``` Activate a turret.
 - ```WASH_ALL_ITEMS``` Wash items with FILTHY flag.
 - ```WASH_HARD_ITEMS``` Wash hard items with FILTHY flag.

src/activity_handlers.cpp

@@ -602,6 +602,7 @@ static void set_up_butchery( player_activity &act, player &u, butcher_type actio
     // workshop butchery (full) prequisites
     if( action == BUTCHER_FULL ) {
         const bool has_rope = u.has_amount( "rope_30", 1 ) || u.has_amount( "rope_makeshift_30", 1 ) ||
+                              u.has_amount( "hd_tow_cable", 1 ) ||
                               u.has_amount( "vine_30", 1 ) || u.has_amount( "grapnel", 1 );
         const bool big_corpse = corpse.size >= MS_MEDIUM;
 
@@ -4875,7 +4876,8 @@ void activity_handlers::spellcasting_finish( player_activity *act, player *p )
                                       spell_being_cast.xp() );
             }
             if( spell_being_cast.get_level() != old_level ) {
-                g->events().send<event_type::player_levels_spell>( spell_being_cast.id(), spell_being_cast.get_level() );
+                g->events().send<event_type::player_levels_spell>( spell_being_cast.id(),
+                        spell_being_cast.get_level() );
             }
         }
     }

src/game.cpp

@@ -1704,8 +1704,8 @@ void game::process_activity()
 
 void game::autopilot_vehicles()
 {
-    for( auto &veh : m.get_vehicles() ) {
-        auto &v = veh.v;
+    for( wrapped_vehicle &veh : m.get_vehicles() ) {
+        vehicle *&v = veh.v;
         if( v->is_following ) {
             v->drive_to_local_target( g->m.getabs( u.pos() ), true );
         } else if( v->is_patrolling ) {
@@ -1920,6 +1920,21 @@ static void update_faction_api( npc *guy )
     }
 }
 
+void game::validate_linked_vehicles()
+{
+    for( auto &veh : m.get_vehicles() ) {
+        vehicle *v = veh.v;
+        if( v->tow_data.other_towing_point != tripoint_zero ) {
+            vehicle *other_v = veh_pointer_or_null( m.veh_at( v->tow_data.other_towing_point ) );
+            if( other_v ) {
+                // the other vehicle is towing us.
+                v->tow_data.set_towing( other_v, v );
+                v->tow_data.other_towing_point = tripoint_zero;
+            }
+        }
+    }
+}
+
 void game::validate_mounted_npcs()
 {
     for( monster &m : all_monsters() ) {
@@ -2771,6 +2786,7 @@ void game::load( const save_t &name )
     validate_npc_followers();
     validate_mounted_npcs();
     validate_camps();
+    validate_linked_vehicles();
     update_map( u );
     for( auto &e : u.inv_dump() ) {
         e->set_owner( g->u );

src/game.h

@@ -488,6 +488,8 @@ class game
         /** validate list of followers to account for overmap buffers */
         void validate_npc_followers();
         void validate_mounted_npcs();
+        /** validate towed vehicles so they get linked up again after a load */
+        void validate_linked_vehicles();
         /** validate camps to ensure they are on the overmap list */
         void validate_camps();
         /** process vehicles that are following the player */

src/item_factory.cpp

@@ -762,6 +762,7 @@ void Item_factory::init()
     add_iuse( "BLECH_BECAUSE_UNCLEAN", &iuse::blech_because_unclean );
     add_iuse( "BOLTCUTTERS", &iuse::boltcutters );
     add_iuse( "C4", &iuse::c4 );
+    add_iuse( "TOW_ATTACH", &iuse::tow_attach );
     add_iuse( "CABLE_ATTACH", &iuse::cable_attach );
     add_iuse( "CAMERA", &iuse::camera );
     add_iuse( "CAN_GOO", &iuse::can_goo );

src/iuse.cpp

@@ -8823,6 +8823,133 @@ int iuse::multicooker( player *p, item *it, bool t, const tripoint &pos )
     return 0;
 }
 
+int iuse::tow_attach( player *p, item *it, bool, const tripoint & )
+{
+    std::string initial_state = it->get_var( "state", "attach_first" );
+    if( !p ) {
+        return 0;
+    }
+    const auto set_cable_active = []( player * p, item * it, const std::string & state ) {
+        it->set_var( "state", state );
+        it->active = true;
+        it->process( p, p->pos(), false );
+        p->moves -= 15;
+    };
+    if( initial_state == "attach_first" ) {
+        const cata::optional<tripoint> posp_ = choose_adjacent(
+                _( "Attach cable to the vehicle that will do the towing." ) );
+        if( !posp_ ) {
+            return 0;
+        }
+        const tripoint posp = *posp_;
+        const optional_vpart_position vp = g->m.veh_at( posp );
+        if( !vp ) {
+            p->add_msg_if_player( _( "There's no vehicle there." ) );
+            return 0;
+        } else {
+            vehicle *const source_veh = veh_pointer_or_null( vp );
+            if( source_veh ) {
+                if( source_veh->has_tow_attached() || source_veh->is_towed() ||
+                    source_veh->is_towing() ) {
+                    p->add_msg_if_player( _( "That vehicle already has a tow-line attached." ) );
+                    return 0;
+                }
+                if( !source_veh->is_external_part( posp ) ) {
+                    p->add_msg_if_player( _( "You can't attach the tow-line to an internal part." ) );
+                    return 0;
+                }
+            }
+            const tripoint &abspos = g->m.getabs( posp );
+            it->set_var( "source_x", abspos.x );
+            it->set_var( "source_y", abspos.y );
+            it->set_var( "source_z", g->get_levz() );
+            set_cable_active( p, it, "pay_out_cable" );
+        }
+    } else {
+        const auto confirm_source_vehicle = []( player * p, item * it, const bool detach_if_missing ) {
+            tripoint source_global( it->get_var( "source_x", 0 ),
+                                    it->get_var( "source_y", 0 ),
+                                    it->get_var( "source_z", 0 ) );
+            tripoint source_local = g->m.getlocal( source_global );
+            const optional_vpart_position source_vp = g->m.veh_at( source_local );
+            vehicle *const source_veh = veh_pointer_or_null( source_vp );
+            if( detach_if_missing && source_veh == nullptr ) {
+                if( p->has_item( *it ) ) {
+                    p->add_msg_if_player( m_bad, _( "You notice the cable has come loose!" ) );
+                }
+                it->reset_cable( p );
+            }
+            return source_vp;
+        };
+
+        const bool paying_out = initial_state == "pay_out_cable";
+        uilist kmenu;
+        kmenu.text = _( "Using cable:" );
+        kmenu.addentry( 0, true, -1, _( "Detach and re-spool the cable" ) );
+        kmenu.addentry( 1, paying_out, -1, _( "Attach loose end to vehicle" ) );
+
+        kmenu.query();
+        int choice = kmenu.ret;
+
+        if( choice < 0 ) {
+            return 0; // we did nothing.
+        } else if( choice == 0 ) { // unconnect & respool
+            it->reset_cable( p );
+            return 0;
+        }
+        const optional_vpart_position source_vp = confirm_source_vehicle( p, it, paying_out );
+        vehicle *const source_veh = veh_pointer_or_null( source_vp );
+        if( source_veh == nullptr && paying_out ) {
+            return 0;
+        }
+        const cata::optional<tripoint> vpos_ = choose_adjacent(
+                _( "Attach cable to vehicle that will be towed." ) );
+        if( !vpos_ ) {
+            return 0;
+        }
+        const tripoint vpos = *vpos_;
+
+        const optional_vpart_position target_vp = g->m.veh_at( vpos );
+        if( !target_vp ) {
+            p->add_msg_if_player( _( "There's no vehicle there." ) );
+            return 0;
+        } else {
+            vehicle *const target_veh = &target_vp->vehicle();
+            if( target_veh && ( target_veh->has_tow_attached() || target_veh->is_towed() ||
+                                target_veh->is_towing() ) ) {
+                p->add_msg_if_player( _( "That vehicle already has a tow-line attached." ) );
+                return 0;
+            }
+            if( source_veh == target_veh ) {
+                if( p->has_item( *it ) ) {
+                    p->add_msg_if_player( m_warning, _( "You cannot set a vehicle to tow itself!" ) );
+                }
+                return 0;
+            }
+            if( !target_veh->is_external_part( vpos ) ) {
+                p->add_msg_if_player( _( "You can't attach the tow-line to an internal part." ) );
+                return 0;
+            }
+            const vpart_id vpid( it->typeId() );
+            point vcoords = source_vp->mount();
+            vehicle_part source_part( vpid, vcoords, item( *it ) );
+            source_veh->install_part( vcoords, source_part );
+            vcoords = target_vp->mount();
+            vehicle_part target_part( vpid, vcoords, item( *it ) );
+            target_veh->install_part( vcoords, target_part );
+
+            if( p->has_item( *it ) ) {
+                p->add_msg_if_player( m_good, _( "You link up the %1$s and the %2$s." ),
+                                      source_veh->name, target_veh->name );
+            }
+            source_veh->tow_data.set_towing( source_veh, target_veh );
+            return 1; // Let the cable be destroyed.
+        }
+    }
+
+    return 0;
+}
+
 int iuse::cable_attach( player *p, item *it, bool, const tripoint & )
 {
     std::string initial_state = it->get_var( "state", "attach_first" );

src/iuse.h

@@ -186,6 +186,7 @@ class iuse
         int camera( player *, item *, bool, const tripoint & );
         int ehandcuffs( player *, item *, bool, const tripoint & );
         int foodperson( player *, item *, bool, const tripoint & );
+        int tow_attach( player *, item *, bool, const tripoint & );
         int cable_attach( player *, item *, bool, const tripoint & );
         int shavekit( player *, item *, bool, const tripoint & );
         int hairkit( player *, item *, bool, const tripoint & );

src/iuse_actor.cpp

@@ -1968,7 +1968,8 @@ int enzlave_actor::use( player &p, item &it, bool t, const tripoint & ) const
 
     for( item &corpse_candidate : items ) {
         const mtype *mt = corpse_candidate.get_mtype();
-        if( corpse_candidate.is_corpse() && mt->in_species( ZOMBIE ) && mt->made_of( material_id( "flesh" ) ) &&
+        if( corpse_candidate.is_corpse() && mt->in_species( ZOMBIE ) &&
+            mt->made_of( material_id( "flesh" ) ) &&
             mt->in_species( HUMAN ) && corpse_candidate.active && !corpse_candidate.has_var( "zlave" ) ) {
             corpses.push_back( &corpse_candidate );
         }

src/map.cpp

@@ -312,7 +312,7 @@ std::unique_ptr<vehicle> map::detach_vehicle( vehicle *veh )
             unboard_vehicle( part, passenger );
         }
     }
-
+    veh->invalidate_towing( true );
     submap *const current_submap = get_submap_at_grid( veh->sm_pos );
     auto &ch = get_cache( z );
     for( size_t i = 0; i < current_submap->vehicles.size(); i++ ) {
@@ -642,6 +642,14 @@ vehicle *map::move_vehicle( vehicle &veh, const tripoint &dp, const tileray &fac
             }
         }
     }
+    if( veh.is_towing() ) {
+        veh.do_towing_move();
+        if( veh.tow_data.get_towed()->tow_cable_too_far() ) {
+            add_msg( m_info, _( "A towing cable snaps off of the %s." ),
+                     veh.tow_data.get_towed()->disp_name() );
+            veh.tow_data.get_towed()->invalidate_towing( true );
+        }
+    }
     // Redraw scene
     // But only if the vehicle was seen before or after the move
     if( seen || sees_veh( g->u, veh, true ) ) {