src/aircraft.h

   1 /*
   2  * This file is part of OpenTTD.
   3  * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
   4  * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   5  * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
   6  */
   7
   8 /** @file aircraft.h Base for aircraft. */
   9
  10 #ifndef AIRCRAFT_H
  11 #define AIRCRAFT_H
  12
  13 #include "station_map.h"
  14 #include "vehicle_base.h"
  15
  16 /**
  17  * Base values for flight levels above ground level for 'normal' flight and holding patterns.
  18  * Due to speed and direction, the actual flight level may be higher.
  19  */
  20 static constexpr int AIRCRAFT_MIN_FLYING_ALTITUDE = 120; ///< Minimum flying altitude above tile.
  21 static constexpr int AIRCRAFT_MAX_FLYING_ALTITUDE = 360; ///< Maximum flying altitude above tile.
  22 static constexpr int PLANE_HOLD_MAX_FLYING_ALTITUDE = 150; ///< holding flying altitude above tile of planes.
  23 static constexpr int HELICOPTER_HOLD_MAX_FLYING_ALTITUDE = 184; ///< holding flying altitude above tile of helicopters.
  24
  25 struct Aircraft;
  26
  27 /** An aircraft can be one of those types. */
  28 enum AircraftSubType {
  29         AIR_HELICOPTER = 0, ///< an helicopter
  30         AIR_AIRCRAFT   = 2, ///< an airplane
  31         AIR_SHADOW     = 4, ///< shadow of the aircraft
  32         AIR_ROTOR      = 6, ///< rotor of an helicopter
  33 };
  34
  35 /** Flags for air vehicles; shared with disaster vehicles. */
  36 enum AirVehicleFlags {
  37         VAF_DEST_TOO_FAR             = 0, ///< Next destination is too far away.
  38
  39         /* The next two flags are to prevent stair climbing of the aircraft. The idea is that the aircraft
  40          * will ascend or descend multiple flight levels at a time instead of following the contours of the
  41          * landscape at a fixed altitude. This only has effect when there are more than 15 height levels. */
  42         VAF_IN_MAX_HEIGHT_CORRECTION = 1, ///< The vehicle is currently lowering its altitude because it hit the upper bound.
  43         VAF_IN_MIN_HEIGHT_CORRECTION = 2, ///< The vehicle is currently raising its altitude because it hit the lower bound.
  44
  45         VAF_HELI_DIRECT_DESCENT      = 3, ///< The helicopter is descending directly at its destination (helipad or in front of hangar)
  46 };
  47
  48 static const int ROTOR_Z_OFFSET         = 5;    ///< Z Offset between helicopter- and rotorsprite.
  49
  50 void HandleAircraftEnterHangar(Aircraft *v);
  51 void GetAircraftSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs, int &yoffs, EngineImageType image_type);
  52 void UpdateAirplanesOnNewStation(const Station *st);
  53 void UpdateAircraftCache(Aircraft *v, bool update_range = false);
  54
  55 void AircraftLeaveHangar(Aircraft *v, Direction exit_dir);
  56 void AircraftNextAirportPos_and_Order(Aircraft *v);
  57 void SetAircraftPosition(Aircraft *v, int x, int y, int z);
  58
  59 void GetAircraftFlightLevelBounds(const Vehicle *v, int *min, int *max);
  60 template <class T>
  61 int GetAircraftFlightLevel(T *v, bool takeoff = false);
  62
  63 /** Variables that are cached to improve performance and such. */
  64 struct AircraftCache {
  65         uint32_t cached_max_range_sqr;   ///< Cached squared maximum range.
  66         uint16_t cached_max_range;       ///< Cached maximum range.
  67 };
  68
  69 /**
  70  * Aircraft, helicopters, rotors and their shadows belong to this class.
  71  */
  72 struct Aircraft final : public SpecializedVehicle<Aircraft, VEH_AIRCRAFT> {
  73         uint16_t crashed_counter;        ///< Timer for handling crash animations.
  74         uint8_t pos;                      ///< Next desired position of the aircraft.
  75         uint8_t previous_pos;             ///< Previous desired position of the aircraft.
  76         StationID targetairport;       ///< Airport to go to next.
  77         uint8_t state;                    ///< State of the airport. @see AirportMovementStates
  78         Direction last_direction;
  79         uint8_t number_consecutive_turns; ///< Protection to prevent the aircraft of making a lot of turns in order to reach a specific point.
  80         uint8_t turn_counter;             ///< Ticks between each turn to prevent > 45 degree turns.
  81         uint8_t flags;                    ///< Aircraft flags. @see AirVehicleFlags
  82
  83         AircraftCache acache;
  84
  85         /** We don't want GCC to zero our struct! It already is zeroed and has an index! */
  86         Aircraft() : SpecializedVehicleBase() {}
  87         /** We want to 'destruct' the right class. */
  88         virtual ~Aircraft() { this->PreDestructor(); }
  89
  90         void MarkDirty() override;
  91         void UpdateDeltaXY() override;
  92         ExpensesType GetExpenseType(bool income) const override { return income ? EXPENSES_AIRCRAFT_REVENUE : EXPENSES_AIRCRAFT_RUN; }
  93         bool IsPrimaryVehicle() const override                  { return this->IsNormalAircraft(); }
  94         void GetImage(Direction direction, EngineImageType image_type, VehicleSpriteSeq *result) const override;
  95         int GetDisplaySpeed() const override    { return this->cur_speed; }
  96         int GetDisplayMaxSpeed() const override { return this->vcache.cached_max_speed; }
  97         int GetSpeedOldUnits() const            { return this->vcache.cached_max_speed * 10 / 128; }
  98         int GetCurrentMaxSpeed() const override { return this->GetSpeedOldUnits(); }
  99         Money GetRunningCost() const override;
 100
 101         bool IsInDepot() const override
 102         {
 103                 assert(this->IsPrimaryVehicle());
 104                 return (this->vehstatus & VS_HIDDEN) != 0 && IsHangarTile(this->tile);
 105         }
 106
 107         bool Tick() override;
 108         void OnNewCalendarDay() override;
 109         void OnNewEconomyDay() override;
 110         uint Crash(bool flooded = false) override;
 111         TileIndex GetOrderStationLocation(StationID station) override;
 112         TileIndex GetCargoTile() const override { return this->First()->tile; }
 113         ClosestDepot FindClosestDepot() override;
 114
 115         /**
 116          * Check if the aircraft type is a normal flying device; eg
 117          * not a rotor or a shadow
 118          * @return Returns true if the aircraft is a helicopter/airplane and
 119          * false if it is a shadow or a rotor
 120          */
 121         inline bool IsNormalAircraft() const
 122         {
 123                 /* To be fully correct the commented out functionality is the proper one,
 124                  * but since value can only be 0 or 2, it is sufficient to only check <= 2
 125                  * return (this->subtype == AIR_HELICOPTER) || (this->subtype == AIR_AIRCRAFT); */
 126                 return this->subtype <= AIR_AIRCRAFT;
 127         }
 128
 129         /**
 130          * Get the range of this aircraft.
 131          * @return Range in tiles or 0 if unlimited range.
 132          */
 133         uint16_t GetRange() const
 134         {
 135                 return this->acache.cached_max_range;
 136         }
 137 };
 138
 139 void GetRotorImage(const Aircraft *v, EngineImageType image_type, VehicleSpriteSeq *result);
 140
 141 Station *GetTargetAirportIfValid(const Aircraft *v);
 142 void HandleMissingAircraftOrders(Aircraft *v);
 143
 144 #endif /* AIRCRAFT_H */