src/roadstop_base.h

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file roadstop_base.h Base class for roadstops. */
  11
  12 #ifndef ROADSTOP_BASE_H
  13 #define ROADSTOP_BASE_H
  14
  15 #include "station_type.h"
  16 #include "core/pool_type.hpp"
  17 #include "core/bitmath_func.hpp"
  18 #include "vehicle_type.h"
  19
  20 typedef Pool<RoadStop, RoadStopID, 32, 64000> RoadStopPool;
  21 extern RoadStopPool _roadstop_pool;
  22
  23 /** A Stop for a Road Vehicle */
  24 struct RoadStop : RoadStopPool::PoolItem<&_roadstop_pool> {
  25         enum RoadStopStatusFlags {
  26                 RSSFB_BAY0_FREE  = 0, ///< Non-zero when bay 0 is free
  27                 RSSFB_BAY1_FREE  = 1, ///< Non-zero when bay 1 is free
  28                 RSSFB_BAY_COUNT  = 2, ///< Max. number of bays
  29                 RSSFB_BASE_ENTRY = 6, ///< Non-zero when the entries on this road stop are the primary, i.e. the ones to delete
  30                 RSSFB_ENTRY_BUSY = 7, ///< Non-zero when roadstop entry is busy
  31         };
  32
  33         /** Container for each entry point of a drive through road stop */
  34         struct Entry {
  35         private:
  36                 int length;      ///< The length of the stop in tile 'units'
  37                 int occupied;    ///< The amount of occupied stop in tile 'units'
  38
  39         public:
  40                 friend struct RoadStop; ///< Oh yeah, the road stop may play with me.
  41
  42                 /** Create an entry */
  43                 Entry() : length(0), occupied(0) {}
  44
  45                 /**
  46                  * Get the length of this drive through stop.
  47                  * @return the length in tile units.
  48                  */
  49                 inline int GetLength() const
  50                 {
  51                         return this->length;
  52                 }
  53
  54                 /**
  55                  * Get the amount of occupied space in this drive through stop.
  56                  * @return the occupied space in tile units.
  57                  */
  58                 inline int GetOccupied() const
  59                 {
  60                         return this->occupied;
  61                 }
  62
  63                 void Leave(const RoadVehicle *rv);
  64                 void Enter(const RoadVehicle *rv);
  65                 void CheckIntegrity(const RoadStop *rs) const;
  66                 void Rebuild(const RoadStop *rs, int side = -1);
  67         };
  68
  69         TileIndex       xy;     ///< Position on the map
  70         byte            status; ///< Current status of the Stop, @see RoadStopSatusFlag. Access using *Bay and *Busy functions.
  71         struct RoadStop *next;  ///< Next stop of the given type at this station
  72
  73         /** Initializes a RoadStop */
  74         inline RoadStop(TileIndex tile = INVALID_TILE) :
  75                 xy(tile),
  76                 status((1 << RSSFB_BAY_COUNT) - 1)
  77         { }
  78
  79         ~RoadStop();
  80
  81         /**
  82          * Checks whether there is a free bay in this road stop
  83          * @return is at least one bay free?
  84          */
  85         inline bool HasFreeBay() const
  86         {
  87                 return GB(this->status, 0, RSSFB_BAY_COUNT) != 0;
  88         }
  89
  90         /**
  91          * Checks whether the given bay is free in this road stop
  92          * @param nr bay to check
  93          * @return is given bay free?
  94          */
  95         inline bool IsFreeBay(uint nr) const
  96         {
  97                 assert(nr < RSSFB_BAY_COUNT);
  98                 return HasBit(this->status, nr);
  99         }
 100
 101         /**
 102          * Checks whether the entrance of the road stop is occupied by a vehicle
 103          * @return is entrance busy?
 104          */
 105         inline bool IsEntranceBusy() const
 106         {
 107                 return HasBit(this->status, RSSFB_ENTRY_BUSY);
 108         }
 109
 110         /**
 111          * Makes an entrance occupied or free
 112          * @param busy If true, marks busy; free otherwise.
 113          */
 114         inline void SetEntranceBusy(bool busy)
 115         {
 116                 SB(this->status, RSSFB_ENTRY_BUSY, 1, busy);
 117         }
 118
 119         /**
 120          * Get the drive through road stop entry struct for the given direction.
 121          * @param dir The direction to get the entry for.
 122          * @return the entry
 123          */
 124         inline const Entry *GetEntry(DiagDirection dir) const
 125         {
 126                 return HasBit((int)dir, 1) ? this->west : this->east;
 127         }
 128
 129         /**
 130          * Get the drive through road stop entry struct for the given direction.
 131          * @param dir The direction to get the entry for.
 132          * @return the entry
 133          */
 134         inline Entry *GetEntry(DiagDirection dir)
 135         {
 136                 return HasBit((int)dir, 1) ? this->west : this->east;
 137         }
 138
 139         void MakeDriveThrough();
 140         void ClearDriveThrough();
 141
 142         void Leave(RoadVehicle *rv);
 143         bool Enter(RoadVehicle *rv);
 144
 145         RoadStop *GetNextRoadStop(const struct RoadVehicle *v) const;
 146
 147         static RoadStop *GetByTile(TileIndex tile, RoadStopType type);
 148
 149         static bool IsDriveThroughRoadStopContinuation(TileIndex rs, TileIndex next);
 150
 151 private:
 152         Entry *east; ///< The vehicles that entered from the east
 153         Entry *west; ///< The vehicles that entered from the west
 154
 155         /**
 156          * Allocates a bay
 157          * @return the allocated bay number
 158          * @pre this->HasFreeBay()
 159          */
 160         inline uint AllocateBay()
 161         {
 162                 assert(this->HasFreeBay());
 163
 164                 /* Find the first free bay. If the bit is set, the bay is free. */
 165                 uint bay_nr = 0;
 166                 while (!HasBit(this->status, bay_nr)) bay_nr++;
 167
 168                 ClrBit(this->status, bay_nr);
 169                 return bay_nr;
 170         }
 171
 172         /**
 173          * Allocates a bay in a drive-through road stop
 174          * @param nr the number of the bay to allocate
 175          */
 176         inline void AllocateDriveThroughBay(uint nr)
 177         {
 178                 assert(nr < RSSFB_BAY_COUNT);
 179                 ClrBit(this->status, nr);
 180         }
 181
 182         /**
 183          * Frees the given bay
 184          * @param nr the number of the bay to free
 185          */
 186         inline void FreeBay(uint nr)
 187         {
 188                 assert(nr < RSSFB_BAY_COUNT);
 189                 SetBit(this->status, nr);
 190         }
 191 };
 192
 193 #define FOR_ALL_ROADSTOPS_FROM(var, start) FOR_ALL_ITEMS_FROM(RoadStop, roadstop_index, var, start)
 194 #define FOR_ALL_ROADSTOPS(var) FOR_ALL_ROADSTOPS_FROM(var, 0)
 195
 196 #endif /* ROADSTOP_BASE_H */