src/rail.cpp

   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 rail.cpp Implementation of rail specific functions. */
  11
  12 #include "stdafx.h"
  13 #include "station_map.h"
  14 #include "tunnelbridge_map.h"
  15 #include "date_func.h"
  16 #include "company_func.h"
  17 #include "company_base.h"
  18 #include "engine_base.h"
  19
  20 #include "safeguards.h"
  21
  22 /* XXX: Below 3 tables store duplicate data. Maybe remove some? */
  23 /* Maps a trackdir to the bit that stores its status in the map arrays, in the
  24  * direction along with the trackdir */
  25 extern const byte _signal_along_trackdir[TRACKDIR_END] = {
  26         0x8, 0x8, 0x8, 0x2, 0x4, 0x1, 0, 0,
  27         0x4, 0x4, 0x4, 0x1, 0x8, 0x2
  28 };
  29
  30 /* Maps a trackdir to the bit that stores its status in the map arrays, in the
  31  * direction against the trackdir */
  32 extern const byte _signal_against_trackdir[TRACKDIR_END] = {
  33         0x4, 0x4, 0x4, 0x1, 0x8, 0x2, 0, 0,
  34         0x8, 0x8, 0x8, 0x2, 0x4, 0x1
  35 };
  36
  37 /* Maps a Track to the bits that store the status of the two signals that can
  38  * be present on the given track */
  39 extern const byte _signal_on_track[] = {
  40         0xC, 0xC, 0xC, 0x3, 0xC, 0x3
  41 };
  42
  43 /* Maps a diagonal direction to the all trackdirs that are connected to any
  44  * track entering in this direction (including those making 90 degree turns)
  45  */
  46 extern const TrackdirBits _exitdir_reaches_trackdirs[] = {
  47         TRACKDIR_BIT_X_NE | TRACKDIR_BIT_LOWER_E | TRACKDIR_BIT_LEFT_N,  // DIAGDIR_NE
  48         TRACKDIR_BIT_Y_SE | TRACKDIR_BIT_LEFT_S  | TRACKDIR_BIT_UPPER_E, // DIAGDIR_SE
  49         TRACKDIR_BIT_X_SW | TRACKDIR_BIT_UPPER_W | TRACKDIR_BIT_RIGHT_S, // DIAGDIR_SW
  50         TRACKDIR_BIT_Y_NW | TRACKDIR_BIT_RIGHT_N | TRACKDIR_BIT_LOWER_W  // DIAGDIR_NW
  51 };
  52
  53 extern const Trackdir _next_trackdir[TRACKDIR_END] = {
  54         TRACKDIR_X_NE,  TRACKDIR_Y_SE,  TRACKDIR_LOWER_E, TRACKDIR_UPPER_E, TRACKDIR_RIGHT_S, TRACKDIR_LEFT_S, INVALID_TRACKDIR, INVALID_TRACKDIR,
  55         TRACKDIR_X_SW,  TRACKDIR_Y_NW,  TRACKDIR_LOWER_W, TRACKDIR_UPPER_W, TRACKDIR_RIGHT_N, TRACKDIR_LEFT_N
  56 };
  57
  58 /* Maps a trackdir to all trackdirs that make 90 deg turns with it. */
  59 extern const TrackdirBits _track_crosses_trackdirs[TRACK_END] = {
  60         TRACKDIR_BIT_Y_SE     | TRACKDIR_BIT_Y_NW,                                                   // TRACK_X
  61         TRACKDIR_BIT_X_NE     | TRACKDIR_BIT_X_SW,                                                   // TRACK_Y
  62         TRACKDIR_BIT_RIGHT_N  | TRACKDIR_BIT_RIGHT_S  | TRACKDIR_BIT_LEFT_N  | TRACKDIR_BIT_LEFT_S,  // TRACK_UPPER
  63         TRACKDIR_BIT_RIGHT_N  | TRACKDIR_BIT_RIGHT_S  | TRACKDIR_BIT_LEFT_N  | TRACKDIR_BIT_LEFT_S,  // TRACK_LOWER
  64         TRACKDIR_BIT_UPPER_W  | TRACKDIR_BIT_UPPER_E  | TRACKDIR_BIT_LOWER_W | TRACKDIR_BIT_LOWER_E, // TRACK_LEFT
  65         TRACKDIR_BIT_UPPER_W  | TRACKDIR_BIT_UPPER_E  | TRACKDIR_BIT_LOWER_W | TRACKDIR_BIT_LOWER_E  // TRACK_RIGHT
  66 };
  67
  68 /* Maps a track to all tracks that make 90 deg turns with it. */
  69 extern const TrackBits _track_crosses_tracks[] = {
  70         TRACK_BIT_Y,    // TRACK_X
  71         TRACK_BIT_X,    // TRACK_Y
  72         TRACK_BIT_VERT, // TRACK_UPPER
  73         TRACK_BIT_VERT, // TRACK_LOWER
  74         TRACK_BIT_HORZ, // TRACK_LEFT
  75         TRACK_BIT_HORZ  // TRACK_RIGHT
  76 };
  77
  78 /* Maps a trackdir to the (4-way) direction the tile is exited when following
  79  * that trackdir */
  80 extern const DiagDirection _trackdir_to_exitdir[TRACKDIR_END] = {
  81         DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_NE, DIAGDIR_SE, DIAGDIR_SW, DIAGDIR_SE, DIAGDIR_NE, DIAGDIR_NE,
  82         DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NW, DIAGDIR_SW, DIAGDIR_NW, DIAGDIR_NE,
  83 };
  84
  85 extern const Trackdir _track_exitdir_to_trackdir[][DIAGDIR_END] = {
  86         {TRACKDIR_X_NE,     INVALID_TRACKDIR,  TRACKDIR_X_SW,     INVALID_TRACKDIR},
  87         {INVALID_TRACKDIR,  TRACKDIR_Y_SE,     INVALID_TRACKDIR,  TRACKDIR_Y_NW},
  88         {TRACKDIR_UPPER_E,  INVALID_TRACKDIR,  INVALID_TRACKDIR,  TRACKDIR_UPPER_W},
  89         {INVALID_TRACKDIR,  TRACKDIR_LOWER_E,  TRACKDIR_LOWER_W,  INVALID_TRACKDIR},
  90         {INVALID_TRACKDIR,  INVALID_TRACKDIR,  TRACKDIR_LEFT_S,   TRACKDIR_LEFT_N},
  91         {TRACKDIR_RIGHT_N,  TRACKDIR_RIGHT_S,  INVALID_TRACKDIR,  INVALID_TRACKDIR}
  92 };
  93
  94 extern const Trackdir _track_enterdir_to_trackdir[][DIAGDIR_END] = {
  95         {TRACKDIR_X_NE,     INVALID_TRACKDIR,  TRACKDIR_X_SW,     INVALID_TRACKDIR},
  96         {INVALID_TRACKDIR,  TRACKDIR_Y_SE,     INVALID_TRACKDIR,  TRACKDIR_Y_NW},
  97         {INVALID_TRACKDIR,  TRACKDIR_UPPER_E,  TRACKDIR_UPPER_W,  INVALID_TRACKDIR},
  98         {TRACKDIR_LOWER_E,  INVALID_TRACKDIR,  INVALID_TRACKDIR,  TRACKDIR_LOWER_W},
  99         {TRACKDIR_LEFT_N,   TRACKDIR_LEFT_S,   INVALID_TRACKDIR,  INVALID_TRACKDIR},
 100         {INVALID_TRACKDIR,  INVALID_TRACKDIR,  TRACKDIR_RIGHT_S,  TRACKDIR_RIGHT_N}
 101 };
 102
 103 extern const Trackdir _track_direction_to_trackdir[][DIR_END] = {
 104         {INVALID_TRACKDIR, TRACKDIR_X_NE,     INVALID_TRACKDIR, INVALID_TRACKDIR,  INVALID_TRACKDIR, TRACKDIR_X_SW,     INVALID_TRACKDIR, INVALID_TRACKDIR},
 105         {INVALID_TRACKDIR, INVALID_TRACKDIR,  INVALID_TRACKDIR, TRACKDIR_Y_SE,     INVALID_TRACKDIR, INVALID_TRACKDIR,  INVALID_TRACKDIR, TRACKDIR_Y_NW},
 106         {INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_UPPER_E, INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_UPPER_W, INVALID_TRACKDIR},
 107         {INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_LOWER_E, INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_LOWER_W, INVALID_TRACKDIR},
 108         {TRACKDIR_LEFT_N,  INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_LEFT_S,  INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR},
 109         {TRACKDIR_RIGHT_N, INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR,  TRACKDIR_RIGHT_S, INVALID_TRACKDIR,  INVALID_TRACKDIR, INVALID_TRACKDIR}
 110 };
 111
 112 extern const Trackdir _dir_to_diag_trackdir[] = {
 113         TRACKDIR_X_NE, TRACKDIR_Y_SE, TRACKDIR_X_SW, TRACKDIR_Y_NW,
 114 };
 115
 116 extern const TrackBits _corner_to_trackbits[] = {
 117         TRACK_BIT_LEFT, TRACK_BIT_LOWER, TRACK_BIT_RIGHT, TRACK_BIT_UPPER,
 118 };
 119
 120 extern const TrackdirBits _uphill_trackdirs[] = {
 121         TRACKDIR_BIT_NONE                    , ///<  0 SLOPE_FLAT
 122         TRACKDIR_BIT_X_SW | TRACKDIR_BIT_Y_NW, ///<  1 SLOPE_W   -> inclined for diagonal track
 123         TRACKDIR_BIT_X_SW | TRACKDIR_BIT_Y_SE, ///<  2 SLOPE_S   -> inclined for diagonal track
 124         TRACKDIR_BIT_X_SW                    , ///<  3 SLOPE_SW
 125         TRACKDIR_BIT_X_NE | TRACKDIR_BIT_Y_SE, ///<  4 SLOPE_E   -> inclined for diagonal track
 126         TRACKDIR_BIT_NONE                    , ///<  5 SLOPE_EW
 127         TRACKDIR_BIT_Y_SE                    , ///<  6 SLOPE_SE
 128         TRACKDIR_BIT_NONE                    , ///<  7 SLOPE_WSE -> leveled
 129         TRACKDIR_BIT_X_NE | TRACKDIR_BIT_Y_NW, ///<  8 SLOPE_N   -> inclined for diagonal track
 130         TRACKDIR_BIT_Y_NW                    , ///<  9 SLOPE_NW
 131         TRACKDIR_BIT_NONE                    , ///< 10 SLOPE_NS
 132         TRACKDIR_BIT_NONE                    , ///< 11 SLOPE_NWS -> leveled
 133         TRACKDIR_BIT_X_NE                    , ///< 12 SLOPE_NE
 134         TRACKDIR_BIT_NONE                    , ///< 13 SLOPE_ENW -> leveled
 135         TRACKDIR_BIT_NONE                    , ///< 14 SLOPE_SEN -> leveled
 136         TRACKDIR_BIT_NONE                    , ///< 15 invalid
 137         TRACKDIR_BIT_NONE                    , ///< 16 invalid
 138         TRACKDIR_BIT_NONE                    , ///< 17 invalid
 139         TRACKDIR_BIT_NONE                    , ///< 18 invalid
 140         TRACKDIR_BIT_NONE                    , ///< 19 invalid
 141         TRACKDIR_BIT_NONE                    , ///< 20 invalid
 142         TRACKDIR_BIT_NONE                    , ///< 21 invalid
 143         TRACKDIR_BIT_NONE                    , ///< 22 invalid
 144         TRACKDIR_BIT_X_SW | TRACKDIR_BIT_Y_SE, ///< 23 SLOPE_STEEP_S -> inclined for diagonal track
 145         TRACKDIR_BIT_NONE                    , ///< 24 invalid
 146         TRACKDIR_BIT_NONE                    , ///< 25 invalid
 147         TRACKDIR_BIT_NONE                    , ///< 26 invalid
 148         TRACKDIR_BIT_X_SW | TRACKDIR_BIT_Y_NW, ///< 27 SLOPE_STEEP_W -> inclined for diagonal track
 149         TRACKDIR_BIT_NONE                    , ///< 28 invalid
 150         TRACKDIR_BIT_X_NE | TRACKDIR_BIT_Y_NW, ///< 29 SLOPE_STEEP_N -> inclined for diagonal track
 151         TRACKDIR_BIT_X_NE | TRACKDIR_BIT_Y_SE, ///< 30 SLOPE_STEEP_E -> inclined for diagonal track
 152 };
 153
 154 /**
 155  * Return the rail type of tile, or INVALID_RAILTYPE if this is no rail tile.
 156  */
 157 RailType GetTileRailType(TileIndex tile)
 158 {
 159         switch (GetTileType(tile)) {
 160                 case MP_RAILWAY:
 161                         return GetRailType(tile);
 162
 163                 case MP_ROAD:
 164                         /* rail/road crossing */
 165                         if (IsLevelCrossing(tile)) return GetRailType(tile);
 166                         break;
 167
 168                 case MP_STATION:
 169                         if (HasStationRail(tile)) return GetRailType(tile);
 170                         break;
 171
 172                 case MP_TUNNELBRIDGE:
 173                         if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) return GetRailType(tile);
 174                         break;
 175
 176                 default:
 177                         break;
 178         }
 179         return INVALID_RAILTYPE;
 180 }
 181
 182 /**
 183  * Finds out if a company has a certain railtype available
 184  * @param company the company in question
 185  * @param railtype requested RailType
 186  * @return true if company has requested RailType available
 187  */
 188 bool HasRailtypeAvail(const CompanyID company, const RailType railtype)
 189 {
 190         return HasBit(Company::Get(company)->avail_railtypes, railtype);
 191 }
 192
 193 /**
 194  * Validate functions for rail building.
 195  * @param rail the railtype to check.
 196  * @return true if the current company may build the rail.
 197  */
 198 bool ValParamRailtype(const RailType rail)
 199 {
 200         return rail < RAILTYPE_END && HasRailtypeAvail(_current_company, rail);
 201 }
 202
 203 /**
 204  * Returns the "best" railtype a company can build.
 205  * As the AI doesn't know what the BEST one is, we have our own priority list
 206  * here. When adding new railtypes, modify this function
 207  * @param company the company "in action"
 208  * @return The "best" railtype a company has available
 209  */
 210 RailType GetBestRailtype(const CompanyID company)
 211 {
 212         if (HasRailtypeAvail(company, RAILTYPE_MAGLEV)) return RAILTYPE_MAGLEV;
 213         if (HasRailtypeAvail(company, RAILTYPE_MONO)) return RAILTYPE_MONO;
 214         if (HasRailtypeAvail(company, RAILTYPE_ELECTRIC)) return RAILTYPE_ELECTRIC;
 215         return RAILTYPE_RAIL;
 216 }
 217
 218 /**
 219  * Add the rail types that are to be introduced at the given date.
 220  * @param current The currently available railtypes.
 221  * @param date    The date for the introduction comparisons.
 222  * @return The rail types that should be available when date
 223  *         introduced rail types are taken into account as well.
 224  */
 225 RailTypes AddDateIntroducedRailTypes(RailTypes current, Date date)
 226 {
 227         RailTypes rts = current;
 228
 229         for (RailType rt = RAILTYPE_BEGIN; rt != RAILTYPE_END; rt++) {
 230                 const RailtypeInfo *rti = GetRailTypeInfo(rt);
 231                 /* Unused rail type. */
 232                 if (rti->label == 0) continue;
 233
 234                 /* Not date introduced. */
 235                 if (!IsInsideMM(rti->introduction_date, 0, MAX_DAY)) continue;
 236
 237                 /* Not yet introduced at this date. */
 238                 if (rti->introduction_date > date) continue;
 239
 240                 /* Have we introduced all required railtypes? */
 241                 RailTypes required = rti->introduction_required_railtypes;
 242                 if ((rts & required) != required) continue;
 243
 244                 rts |= rti->introduces_railtypes;
 245         }
 246
 247         /* When we added railtypes we need to run this method again; the added
 248          * railtypes might enable more rail types to become introduced. */
 249         return rts == current ? rts : AddDateIntroducedRailTypes(rts, date);
 250 }
 251
 252 /**
 253  * Get the rail types the given company can build.
 254  * @param c the company to get the rail types for.
 255  * @return the rail types.
 256  */
 257 RailTypes GetCompanyRailtypes(CompanyID company)
 258 {
 259         RailTypes rts = RAILTYPES_NONE;
 260
 261         Engine *e;
 262         FOR_ALL_ENGINES_OF_TYPE(e, VEH_TRAIN) {
 263                 const EngineInfo *ei = &e->info;
 264
 265                 if (HasBit(ei->climates, _settings_game.game_creation.landscape) &&
 266                                 (HasBit(e->company_avail, company) || _date >= e->intro_date + DAYS_IN_YEAR)) {
 267                         const RailVehicleInfo *rvi = &e->u.rail;
 268
 269                         if (rvi->railveh_type != RAILVEH_WAGON) {
 270                                 assert(rvi->railtype < RAILTYPE_END);
 271                                 rts |= GetRailTypeInfo(rvi->railtype)->introduces_railtypes;
 272                         }
 273                 }
 274         }
 275
 276         return AddDateIntroducedRailTypes(rts, _date);
 277 }
 278
 279 /**
 280  * Get the rail type for a given label.
 281  * @param label the railtype label.
 282  * @param allow_alternate_labels Search in the alternate label lists as well.
 283  * @return the railtype.
 284  */
 285 RailType GetRailTypeByLabel(RailTypeLabel label, bool allow_alternate_labels)
 286 {
 287         /* Loop through each rail type until the label is found */
 288         for (RailType r = RAILTYPE_BEGIN; r != RAILTYPE_END; r++) {
 289                 const RailtypeInfo *rti = GetRailTypeInfo(r);
 290                 if (rti->label == label) return r;
 291         }
 292
 293         if (allow_alternate_labels) {
 294                 /* Test if any rail type defines the label as an alternate. */
 295                 for (RailType r = RAILTYPE_BEGIN; r != RAILTYPE_END; r++) {
 296                         const RailtypeInfo *rti = GetRailTypeInfo(r);
 297                         if (rti->alternate_labels.Contains(label)) return r;
 298                 }
 299         }
 300
 301         /* No matching label was found, so it is invalid */
 302         return INVALID_RAILTYPE;
 303 }