newgrf_engine.cpp

Go to the documentation of this file.

/* $Id: newgrf_engine.cpp 14801 2009-01-03 13:20:32Z rubidium $ */

#include "stdafx.h"
#include "openttd.h"
#include "variables.h"
#include "debug.h"
#include "engine_func.h"
#include "engine_base.h"
#include "train.h"
#include "company_func.h"
#include "company_base.h"
#include "station_base.h"
#include "airport.h"
#include "newgrf.h"
#include "newgrf_callbacks.h"
#include "newgrf_engine.h"
#include "newgrf_station.h"
#include "newgrf_spritegroup.h"
#include "newgrf_cargo.h"
#include "cargotype.h"
#include "date_func.h"
#include "vehicle_func.h"
#include "core/random_func.hpp"
#include "direction_func.h"
#include "rail_map.h"
#include "rail.h"
#include "settings_type.h"
#include "aircraft.h"
#include "core/smallmap_type.hpp"


int _traininfo_vehicle_pitch = 0;
int _traininfo_vehicle_width = 29;

struct WagonOverride {
  EngineID *train_id;
  uint trains;
  CargoID cargo;
  const SpriteGroup *group;
};

void SetWagonOverrideSprites(EngineID engine, CargoID cargo, const SpriteGroup *group, EngineID *train_id, uint trains)
{
  Engine *e = GetEngine(engine);
  WagonOverride *wo;

  assert(cargo < NUM_CARGO + 2); // Include CT_DEFAULT and CT_PURCHASE pseudo cargos.

  e->overrides_count++;
  e->overrides = ReallocT(e->overrides, e->overrides_count);

  wo = &e->overrides[e->overrides_count - 1];
  wo->group = group;
  wo->cargo = cargo;
  wo->trains = trains;
  wo->train_id = MallocT<EngineID>(trains);
  memcpy(wo->train_id, train_id, trains * sizeof *train_id);
}

const SpriteGroup *GetWagonOverrideSpriteSet(EngineID engine, CargoID cargo, EngineID overriding_engine)
{
  const Engine *e = GetEngine(engine);

  /* XXX: This could turn out to be a timesink on profiles. We could
   * always just dedicate 65535 bytes for an [engine][train] trampoline
   * for O(1). Or O(logMlogN) and searching binary tree or smt. like
   * that. --pasky */

  for (uint i = 0; i < e->overrides_count; i++) {
    const WagonOverride *wo = &e->overrides[i];

    if (wo->cargo != cargo && wo->cargo != CT_DEFAULT) continue;

    for (uint j = 0; j < wo->trains; j++) {
      if (wo->train_id[j] == overriding_engine) return wo->group;
    }
  }
  return NULL;
}

void UnloadWagonOverrides(Engine *e)
{
  for (uint i = 0; i < e->overrides_count; i++) {
    WagonOverride *wo = &e->overrides[i];
    free(wo->train_id);
  }
  free(e->overrides);
  e->overrides_count = 0;
  e->overrides = NULL;
}


void SetCustomEngineSprites(EngineID engine, byte cargo, const SpriteGroup *group)
{
  Engine *e = GetEngine(engine);
  assert(cargo < lengthof(e->group));

  if (e->group[cargo] != NULL) {
    grfmsg(6, "SetCustomEngineSprites: engine %d cargo %d already has group -- replacing", engine, cargo);
  }
  e->group[cargo] = group;
}


void SetEngineGRF(EngineID engine, const GRFFile *file)
{
  Engine *e = GetEngine(engine);
  e->grffile = file;
}


const GRFFile *GetEngineGRF(EngineID engine)
{
  return GetEngine(engine)->grffile;
}


uint32 GetEngineGRFID(EngineID engine)
{
  return GetEngineGRF(engine)->grfid;
}


static int MapOldSubType(const Vehicle *v)
{
  if (v->type != VEH_TRAIN) return v->subtype;
  if (IsTrainEngine(v)) return 0;
  if (IsFreeWagon(v)) return 4;
  return 2;
}


/* TTDP style aircraft movement states for GRF Action 2 Var 0xE2 */
enum {
  AMS_TTDP_HANGAR,
  AMS_TTDP_TO_HANGAR,
  AMS_TTDP_TO_PAD1,
  AMS_TTDP_TO_PAD2,
  AMS_TTDP_TO_PAD3,
  AMS_TTDP_TO_ENTRY_2_AND_3,
  AMS_TTDP_TO_ENTRY_2_AND_3_AND_H,
  AMS_TTDP_TO_JUNCTION,
  AMS_TTDP_LEAVE_RUNWAY,
  AMS_TTDP_TO_INWAY,
  AMS_TTDP_TO_RUNWAY,
  AMS_TTDP_TO_OUTWAY,
  AMS_TTDP_WAITING,
  AMS_TTDP_TAKEOFF,
  AMS_TTDP_TO_TAKEOFF,
  AMS_TTDP_CLIMBING,
  AMS_TTDP_FLIGHT_APPROACH,
  AMS_TTDP_UNUSED_0x11,
  AMS_TTDP_FLIGHT_TO_TOWER,
  AMS_TTDP_UNUSED_0x13,
  AMS_TTDP_FLIGHT_FINAL,
  AMS_TTDP_FLIGHT_DESCENT,
  AMS_TTDP_BRAKING,
  AMS_TTDP_HELI_TAKEOFF_AIRPORT,
  AMS_TTDP_HELI_TO_TAKEOFF_AIRPORT,
  AMS_TTDP_HELI_LAND_AIRPORT,
  AMS_TTDP_HELI_TAKEOFF_HELIPORT,
  AMS_TTDP_HELI_TO_TAKEOFF_HELIPORT,
  AMS_TTDP_HELI_LAND_HELIPORT,
};


static byte MapAircraftMovementState(const Vehicle *v)
{
  const Station *st = GetTargetAirportIfValid(v);
  if (st == NULL) return AMS_TTDP_FLIGHT_TO_TOWER;

  const AirportFTAClass *afc = st->Airport();
  uint16 amdflag = afc->MovingData(v->u.air.pos)->flag;

  switch (v->u.air.state) {
    case HANGAR:
      /* The international airport is a special case as helicopters can land in
       * front of the hanger. Helicopters also change their air.state to
       * AMED_HELI_LOWER some time before actually descending. */

      /* This condition only occurs for helicopters, during descent,
       * to a landing by the hanger of an international airport. */
      if (amdflag & AMED_HELI_LOWER) return AMS_TTDP_HELI_LAND_AIRPORT;

      /* This condition only occurs for helicopters, before starting descent,
       * to a landing by the hanger of an international airport. */
      if (amdflag & AMED_SLOWTURN) return AMS_TTDP_FLIGHT_TO_TOWER;

      /* The final two conditions apply to helicopters or aircraft.
       * Has reached hanger? */
      if (amdflag & AMED_EXACTPOS) return AMS_TTDP_HANGAR;

      /* Still moving towards hanger. */
      return AMS_TTDP_TO_HANGAR;

    case TERM1:
      if (amdflag & AMED_EXACTPOS) return AMS_TTDP_TO_PAD1;
      return AMS_TTDP_TO_JUNCTION;

    case TERM2:
      if (amdflag & AMED_EXACTPOS) return AMS_TTDP_TO_PAD2;
      return AMS_TTDP_TO_ENTRY_2_AND_3_AND_H;

    case TERM3:
    case TERM4:
    case TERM5:
    case TERM6:
    case TERM7:
    case TERM8:
      /* TTDPatch only has 3 terminals, so treat these states the same */
      if (amdflag & AMED_EXACTPOS) return AMS_TTDP_TO_PAD3;
      return AMS_TTDP_TO_ENTRY_2_AND_3_AND_H;

    case HELIPAD1:
    case HELIPAD2:
    case HELIPAD3:
    case HELIPAD4: // Will only occur for helicopters.
      if (amdflag & AMED_HELI_LOWER) return AMS_TTDP_HELI_LAND_AIRPORT; // Descending.
      if (amdflag & AMED_SLOWTURN)   return AMS_TTDP_FLIGHT_TO_TOWER;   // Still hasn't started descent.
      return AMS_TTDP_TO_JUNCTION; // On the ground.

    case TAKEOFF: // Moving to takeoff position.
      return AMS_TTDP_TO_OUTWAY;

    case STARTTAKEOFF: // Accelerating down runway.
      return AMS_TTDP_TAKEOFF;

    case ENDTAKEOFF: // Ascent
      return AMS_TTDP_CLIMBING;

    case HELITAKEOFF: // Helicopter is moving to take off position.
      if (afc->delta_z == 0) {
        return amdflag & AMED_HELI_RAISE ?
          AMS_TTDP_HELI_TAKEOFF_AIRPORT : AMS_TTDP_TO_JUNCTION;
      } else {
        return AMS_TTDP_HELI_TAKEOFF_HELIPORT;
      }

    case FLYING:
      return amdflag & AMED_HOLD ? AMS_TTDP_FLIGHT_APPROACH : AMS_TTDP_FLIGHT_TO_TOWER;

    case LANDING: // Descent
      return AMS_TTDP_FLIGHT_DESCENT;

    case ENDLANDING: // On the runway braking
      if (amdflag & AMED_BRAKE) return AMS_TTDP_BRAKING;
      /* Landed - moving off runway */
      return AMS_TTDP_TO_INWAY;

    case HELILANDING:
    case HELIENDLANDING: // Helicoptor is decending.
      if (amdflag & AMED_HELI_LOWER) {
        return afc->delta_z == 0 ?
          AMS_TTDP_HELI_LAND_AIRPORT : AMS_TTDP_HELI_LAND_HELIPORT;
      } else {
        return AMS_TTDP_FLIGHT_TO_TOWER;
      }

    default:
      return AMS_TTDP_HANGAR;
  }
}


/* TTDP style aircraft movement action for GRF Action 2 Var 0xE6 */
enum {
  AMA_TTDP_IN_HANGAR,
  AMA_TTDP_ON_PAD1,
  AMA_TTDP_ON_PAD2,
  AMA_TTDP_ON_PAD3,
  AMA_TTDP_HANGAR_TO_PAD1,
  AMA_TTDP_HANGAR_TO_PAD2,
  AMA_TTDP_HANGAR_TO_PAD3,
  AMA_TTDP_LANDING_TO_PAD1,
  AMA_TTDP_LANDING_TO_PAD2,
  AMA_TTDP_LANDING_TO_PAD3,
  AMA_TTDP_PAD1_TO_HANGAR,
  AMA_TTDP_PAD2_TO_HANGAR,
  AMA_TTDP_PAD3_TO_HANGAR,
  AMA_TTDP_PAD1_TO_TAKEOFF,
  AMA_TTDP_PAD2_TO_TAKEOFF,
  AMA_TTDP_PAD3_TO_TAKEOFF,
  AMA_TTDP_HANGAR_TO_TAKOFF,
  AMA_TTDP_LANDING_TO_HANGAR,
  AMA_TTDP_IN_FLIGHT,
};


static byte MapAircraftMovementAction(const Vehicle *v)
{
  switch (v->u.air.state) {
    case HANGAR:
      return (v->cur_speed > 0) ? AMA_TTDP_LANDING_TO_HANGAR : AMA_TTDP_IN_HANGAR;

    case TERM1:
    case HELIPAD1:
      return (v->current_order.IsType(OT_LOADING)) ? AMA_TTDP_ON_PAD1 : AMA_TTDP_LANDING_TO_PAD1;

    case TERM2:
    case HELIPAD2:
      return (v->current_order.IsType(OT_LOADING)) ? AMA_TTDP_ON_PAD2 : AMA_TTDP_LANDING_TO_PAD2;

    case TERM3:
    case TERM4:
    case TERM5:
    case TERM6:
    case TERM7:
    case TERM8:
    case HELIPAD3:
    case HELIPAD4:
      return (v->current_order.IsType(OT_LOADING)) ? AMA_TTDP_ON_PAD3 : AMA_TTDP_LANDING_TO_PAD3;

    case TAKEOFF:      // Moving to takeoff position
    case STARTTAKEOFF: // Accelerating down runway
    case ENDTAKEOFF:   // Ascent
    case HELITAKEOFF:
      /* @todo Need to find which terminal (or hanger) we've come from. How? */
      return AMA_TTDP_PAD1_TO_TAKEOFF;

    case FLYING:
      return AMA_TTDP_IN_FLIGHT;

    case LANDING:    // Descent
    case ENDLANDING: // On the runway braking
    case HELILANDING:
    case HELIENDLANDING:
      /* @todo Need to check terminal we're landing to. Is it known yet? */
      return (v->current_order.IsType(OT_GOTO_DEPOT)) ?
        AMA_TTDP_LANDING_TO_HANGAR : AMA_TTDP_LANDING_TO_PAD1;

    default:
      return AMA_TTDP_IN_HANGAR;
  }
}


/* TTDP airport types. Used to map our types to TTDPatch's */
enum {
  ATP_TTDP_SMALL,
  ATP_TTDP_LARGE,
  ATP_TTDP_HELIPORT,
  ATP_TTDP_OILRIG,
};


/* Vehicle Resolver Functions */
static inline const Vehicle *GRV(const ResolverObject *object)
{
  switch (object->scope) {
    default: NOT_REACHED();
    case VSG_SCOPE_SELF: return object->u.vehicle.self;
    case VSG_SCOPE_PARENT: return object->u.vehicle.parent;
    case VSG_SCOPE_RELATIVE: {
      const Vehicle *v = NULL;
      switch (GB(object->count, 6, 2)) {
        default: NOT_REACHED();
        case 0x00: // count back (away from the engine), starting at this vehicle
        case 0x01: // count forward (toward the engine), starting at this vehicle
          v = object->u.vehicle.self;
          break;
        case 0x02: // count back, starting at the engine
          v = object->u.vehicle.parent;
          break;
        case 0x03: { // count back, starting at the first vehicle in this chain of vehicles with the same ID, as for vehicle variable 41
          const Vehicle *self = object->u.vehicle.self;
          for (const Vehicle *u = self->First(); u != self; u = u->Next()) {
            if (u->engine_type != self->engine_type) {
              v = NULL;
            } else {
              if (v == NULL) v = u;
            }
          }
          if (v == NULL) v = self;
        } break;
      }
      uint32 count = GB(object->count, 0, 4);
      if (count == 0) count = GetRegister(0x100);
      while (v != NULL && count-- != 0) v = (GB(object->count, 6, 2) == 0x01) ? v->Previous() : v->Next();
      return v;
    }
  }
}


static uint32 VehicleGetRandomBits(const ResolverObject *object)
{
  return GRV(object) == NULL ? 0 : GRV(object)->random_bits;
}


static uint32 VehicleGetTriggers(const ResolverObject *object)
{
  return GRV(object) == NULL ? 0 : GRV(object)->waiting_triggers;
}


static void VehicleSetTriggers(const ResolverObject *object, int triggers)
{
  /* Evil cast to get around const-ness. This used to be achieved by an
   * innocent looking function pointer cast... Currently I cannot see a
   * way of avoiding this without removing consts deep within gui code.
   */
  Vehicle *v = (Vehicle*)GRV(object);

  /* This function must only be called when processing triggers -- any
   * other time is an error. */
  assert(object->trigger != 0);

  if (v != NULL) v->waiting_triggers = triggers;
}


static uint8 LiveryHelper(EngineID engine, const Vehicle *v)
{
  const Livery *l;

  if (v == NULL) {
    if (!IsValidCompanyID(_current_company)) return 0;
    l = GetEngineLivery(engine, _current_company, INVALID_ENGINE, NULL);
  } else if (v->type == VEH_TRAIN) {
    l = GetEngineLivery((v->u.rail.first_engine != INVALID_ENGINE && (IsArticulatedPart(v) || UsesWagonOverride(v))) ? v->u.rail.first_engine : v->engine_type, v->owner, v->u.rail.first_engine, v);
  } else {
    l = GetEngineLivery(v->engine_type, v->owner, INVALID_ENGINE, v);
  }

  return l->colour1 + l->colour2 * 16;
}


static uint32 VehicleGetVariable(const ResolverObject *object, byte variable, byte parameter, bool *available)
{
  const Vehicle *v = GRV(object);

  if (v == NULL) {
    /* Vehicle does not exist, so we're in a purchase list */
    switch (variable) {
      case 0x43: return _current_company | (LiveryHelper(object->u.vehicle.self_type, NULL) << 24); // Owner information
      case 0x46: return 0;               // Motion counter
      case 0x48: return GetEngine(object->u.vehicle.self_type)->flags; // Vehicle Type Info
      case 0x49: return _cur_year; // 'Long' format build year
      case 0xC4: return Clamp(_cur_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR; // Build year
      case 0xDA: return INVALID_VEHICLE; // Next vehicle
    }

    *available = false;
    return UINT_MAX;
  }

  /* Calculated vehicle parameters */
  switch (variable) {
    case 0x40: // Get length of consist
    case 0x41: // Get length of same consecutive wagons
      {
        const Vehicle* u;
        byte chain_before = 0;
        byte chain_after  = 0;

        for (u = v->First(); u != v; u = u->Next()) {
          chain_before++;
          if (variable == 0x41 && u->engine_type != v->engine_type) chain_before = 0;
        }

        while (u->Next() != NULL && (variable == 0x40 || u->Next()->engine_type == v->engine_type)) {
          chain_after++;
          u = u->Next();
        }

        return chain_before | chain_after << 8 | (chain_before + chain_after + (variable == 0x41)) << 16;
      }

    case 0x42: { // Consist cargo information
      const Vehicle *u;
      byte cargo_classes = 0;
      uint8 common_cargo_best = 0;
      uint8 common_cargos[NUM_CARGO];
      uint8 common_subtype_best = 0;
      uint8 common_subtypes[256];
      byte user_def_data = 0;
      CargoID common_cargo_type = CT_PASSENGERS;
      uint8 common_subtype = 0;

      /* Reset our arrays */
      memset(common_cargos, 0, sizeof(common_cargos));
      memset(common_subtypes, 0, sizeof(common_subtypes));

      for (u = v; u != NULL; u = u->Next()) {
        if (v->type == VEH_TRAIN) user_def_data |= u->u.rail.user_def_data;

        /* Skip empty engines */
        if (u->cargo_cap == 0) continue;

        cargo_classes |= GetCargo(u->cargo_type)->classes;
        common_cargos[u->cargo_type]++;
        common_subtypes[u->cargo_subtype]++;
      }

      /* Pick the most common cargo type */
      for (CargoID cargo = 0; cargo < NUM_CARGO; cargo++) {
        if (common_cargos[cargo] > common_cargo_best) {
          common_cargo_best = common_cargos[cargo];
          common_cargo_type = GetCargo(cargo)->bitnum;
        }
      }

      for (uint i = 0; i < lengthof(common_subtypes); i++) {
        if (common_subtypes[i] > common_subtype_best) {
          common_subtype_best = common_subtypes[i];
          common_subtype = i;
        }
      }

      return cargo_classes | (common_cargo_type << 8) | (common_subtype << 16) | (user_def_data << 24);
    }

    case 0x43: // Company information
      return v->owner | (GetCompany(v->owner)->is_ai ? 0x10000 : 0) | (LiveryHelper(v->engine_type, v) << 24);

    case 0x44: // Aircraft information
      if (v->type != VEH_AIRCRAFT) return UINT_MAX;

      {
        const Vehicle *w = v->Next();
        uint16 altitude = v->z_pos - w->z_pos; // Aircraft height - shadow height
        byte airporttype = ATP_TTDP_LARGE;

        const Station *st = GetTargetAirportIfValid(v);

        if (st != NULL) {
          switch (st->airport_type) {
            /* Note, Helidepot and Helistation are treated as small airports
             * as they are at ground level. */
            case AT_HELIDEPOT:
            case AT_HELISTATION:
            case AT_COMMUTER:
            case AT_SMALL:         airporttype = ATP_TTDP_SMALL; break;
            case AT_METROPOLITAN:
            case AT_INTERNATIONAL:
            case AT_INTERCON:
            case AT_LARGE:         airporttype = ATP_TTDP_LARGE; break;
            case AT_HELIPORT:      airporttype = ATP_TTDP_HELIPORT; break;
            case AT_OILRIG:        airporttype = ATP_TTDP_OILRIG; break;
            default:               airporttype = ATP_TTDP_LARGE; break;
          }
        }

        return (altitude << 8) | airporttype;
      }

    case 0x45: { // Curvature info
      /* Format: xxxTxBxF
       * F - previous wagon to current wagon, 0 if vehicle is first
       * B - current wagon to next wagon, 0 if wagon is last
       * T - previous wagon to next wagon, 0 in an S-bend
       */
      if (v->type != VEH_TRAIN) return 0;

      const Vehicle *u_p = v->Previous();
      const Vehicle *u_n = v->Next();
      DirDiff f = (u_p == NULL) ?  DIRDIFF_SAME : DirDifference(u_p->direction, v->direction);
      DirDiff b = (u_n == NULL) ?  DIRDIFF_SAME : DirDifference(v->direction, u_n->direction);
      DirDiff t = ChangeDirDiff(f, b);

      return ((t > DIRDIFF_REVERSE ? t | 8 : t) << 16) |
             ((b > DIRDIFF_REVERSE ? b | 8 : b) <<  8) |
             ( f > DIRDIFF_REVERSE ? f | 8 : f);
    }

    case 0x46: // Motion counter
      return v->motion_counter;

    case 0x47: { // Vehicle cargo info
      /* Format: ccccwwtt
       * tt - the cargo type transported by the vehicle,
       *     translated if a translation table has been installed.
       * ww - cargo unit weight in 1/16 tons, same as cargo prop. 0F.
       * cccc - the cargo class value of the cargo transported by the vehicle.
       */
      const CargoSpec *cs = GetCargo(v->cargo_type);

      return (cs->classes << 16) | (cs->weight << 8) | GetEngineGRF(v->engine_type)->cargo_map[v->cargo_type];
    }

    case 0x48: return GetEngine(v->engine_type)->flags; // Vehicle Type Info
    case 0x49: return v->build_year;

    /* Variables which use the parameter */
    case 0x60: // Count consist's engine ID occurance
      //EngineID engine = GetNewEngineID(GetEngineGRF(v->engine_type), v->type, parameter);
      if (v->type != VEH_TRAIN) return GetEngine(v->engine_type)->internal_id == parameter;

      {
        uint count = 0;
        for (; v != NULL; v = v->Next()) {
          if (GetEngine(v->engine_type)->internal_id == parameter) count++;
        }
        return count;
      }

    case 0xFE:
    case 0xFF: {
      uint16 modflags = 0;

      if (v->type == VEH_TRAIN) {
        const Vehicle *u = IsTrainWagon(v) && HasBit(v->vehicle_flags, VRF_POWEREDWAGON) ? v->First() : v;
        RailType railtype = GetRailType(v->tile);
        bool powered = IsTrainEngine(v) || (IsTrainWagon(v) && HasBit(v->vehicle_flags, VRF_POWEREDWAGON));
        bool has_power = powered && HasPowerOnRail(u->u.rail.railtype, railtype);
        bool is_electric = powered && u->u.rail.railtype == RAILTYPE_ELECTRIC;

        if (has_power) SetBit(modflags, 5);
        if (is_electric && !has_power) SetBit(modflags, 6);
        if (HasBit(v->u.rail.flags, VRF_TOGGLE_REVERSE)) SetBit(modflags, 8);
      }
      if (HasBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE)) SetBit(modflags, 10);

      return variable == 0xFE ? modflags : GB(modflags, 8, 8);
    }
  }

  /* General vehicle properties */
  switch (variable - 0x80) {
    case 0x00: return v->type;
    case 0x01: return MapOldSubType(v);
    case 0x04: return v->index;
    case 0x05: return GB(v->index, 8, 8);
    case 0x0A: return v->current_order.Pack();
    case 0x0B: return GB(v->current_order.Pack(), 8, 8);
    case 0x0C: return v->GetNumOrders();
    case 0x0D: return v->cur_order_index;
    case 0x10: return v->load_unload_time_rem;
    case 0x11: return GB(v->load_unload_time_rem, 8, 8);
    case 0x12: return max(v->date_of_last_service - DAYS_TILL_ORIGINAL_BASE_YEAR, 0);
    case 0x13: return GB(max(v->date_of_last_service - DAYS_TILL_ORIGINAL_BASE_YEAR, 0), 8, 8);
    case 0x14: return v->service_interval;
    case 0x15: return GB(v->service_interval, 8, 8);
    case 0x16: return v->last_station_visited;
    case 0x17: return v->tick_counter;
    case 0x18: return v->max_speed;
    case 0x19: return GB(v->max_speed, 8, 8);
    case 0x1A: return v->x_pos;
    case 0x1B: return GB(v->x_pos, 8, 8);
    case 0x1C: return v->y_pos;
    case 0x1D: return GB(v->y_pos, 8, 8);
    case 0x1E: return v->z_pos;
    case 0x1F: return object->info_view ? DIR_W : v->direction;
    case 0x28: return v->cur_image;
    case 0x29: return GB(v->cur_image, 8, 8);
    case 0x32: return v->vehstatus;
    case 0x33: return 0; // non-existent high byte of vehstatus
    case 0x34: return v->cur_speed;
    case 0x35: return GB(v->cur_speed, 8, 8);
    case 0x36: return v->subspeed;
    case 0x37: return v->acceleration;
    case 0x39: return v->cargo_type;
    case 0x3A: return v->cargo_cap;
    case 0x3B: return GB(v->cargo_cap, 8, 8);
    case 0x3C: return v->cargo.Count();
    case 0x3D: return GB(v->cargo.Count(), 8, 8);
    case 0x3E: return v->cargo.Source();
    case 0x3F: return v->cargo.DaysInTransit();
    case 0x40: return v->age;
    case 0x41: return GB(v->age, 8, 8);
    case 0x42: return v->max_age;
    case 0x43: return GB(v->max_age, 8, 8);
    case 0x44: return Clamp(v->build_year, ORIGINAL_BASE_YEAR, ORIGINAL_MAX_YEAR) - ORIGINAL_BASE_YEAR;
    case 0x45: return v->unitnumber;
    case 0x46: return GetEngine(v->engine_type)->internal_id;
    case 0x47: return GB(GetEngine(v->engine_type)->internal_id, 8, 8);
    case 0x48:
      if (v->type != VEH_TRAIN || v->spritenum != 0xFD) return v->spritenum;
      return HasBit(v->u.rail.flags, VRF_REVERSE_DIRECTION) ? 0xFE : 0xFD;

    case 0x49: return v->day_counter;
    case 0x4A: return v->breakdowns_since_last_service;
    case 0x4B: return v->breakdown_ctr;
    case 0x4C: return v->breakdown_delay;
    case 0x4D: return v->breakdown_chance;
    case 0x4E: return v->reliability;
    case 0x4F: return GB(v->reliability, 8, 8);
    case 0x50: return v->reliability_spd_dec;
    case 0x51: return GB(v->reliability_spd_dec, 8, 8);
    case 0x52: return ClampToI32(v->GetDisplayProfitThisYear());
    case 0x53: return GB(ClampToI32(v->GetDisplayProfitThisYear()),  8, 24);
    case 0x54: return GB(ClampToI32(v->GetDisplayProfitThisYear()), 16, 16);
    case 0x55: return GB(ClampToI32(v->GetDisplayProfitThisYear()), 24,  8);
    case 0x56: return ClampToI32(v->GetDisplayProfitLastYear());
    case 0x57: return GB(ClampToI32(v->GetDisplayProfitLastYear()),  8, 24);
    case 0x58: return GB(ClampToI32(v->GetDisplayProfitLastYear()), 16, 16);
    case 0x59: return GB(ClampToI32(v->GetDisplayProfitLastYear()), 24,  8);
    case 0x5A: return v->Next() == NULL ? INVALID_VEHICLE : v->Next()->index;
    case 0x5C: return ClampToI32(v->value);
    case 0x5D: return GB(ClampToI32(v->value),  8, 24);
    case 0x5E: return GB(ClampToI32(v->value), 16, 16);
    case 0x5F: return GB(ClampToI32(v->value), 24,  8);
    case 0x72: return v->cargo_subtype;
    case 0x7A: return v->random_bits;
    case 0x7B: return v->waiting_triggers;
  }

  /* Vehicle specific properties */
  switch (v->type) {
    case VEH_TRAIN:
      switch (variable - 0x80) {
        case 0x62: return v->u.rail.track;
        case 0x66: return v->u.rail.railtype;
        case 0x73: return v->u.rail.cached_veh_length;
        case 0x74: return v->u.rail.cached_power;
        case 0x75: return GB(v->u.rail.cached_power,  8, 24);
        case 0x76: return GB(v->u.rail.cached_power, 16, 16);
        case 0x77: return GB(v->u.rail.cached_power, 24,  8);
        case 0x7C: return v->First()->index;
        case 0x7D: return GB(v->First()->index, 8, 8);
        case 0x7F: return 0; // Used for vehicle reversing hack in TTDP
      }
      break;

    case VEH_ROAD:
      switch (variable - 0x80) {
        case 0x62: return v->u.road.state;
        case 0x64: return v->u.road.blocked_ctr;
        case 0x65: return GB(v->u.road.blocked_ctr, 8, 8);
        case 0x66: return v->u.road.overtaking;
        case 0x67: return v->u.road.overtaking_ctr;
        case 0x68: return v->u.road.crashed_ctr;
        case 0x69: return GB(v->u.road.crashed_ctr, 8, 8);
      }
      break;

    case VEH_AIRCRAFT:
      switch (variable - 0x80) {
        case 0x62: return MapAircraftMovementState(v);  // Current movement state
        case 0x63: return v->u.air.targetairport;       // Airport to which the action refers
        case 0x66: return MapAircraftMovementAction(v); // Current movement action
      }
      break;

    default: break;
  }

  DEBUG(grf, 1, "Unhandled vehicle property 0x%X, type 0x%X", variable, v->type);

  *available = false;
  return UINT_MAX;
}


static const SpriteGroup *VehicleResolveReal(const ResolverObject *object, const SpriteGroup *group)
{
  const Vehicle *v = object->u.vehicle.self;

  if (v == NULL) {
    if (group->g.real.num_loading > 0) return group->g.real.loading[0];
    if (group->g.real.num_loaded  > 0) return group->g.real.loaded[0];
    return NULL;
  }

  bool in_motion = !v->First()->current_order.IsType(OT_LOADING);

  uint totalsets = in_motion ? group->g.real.num_loaded : group->g.real.num_loading;

  uint set = (v->cargo.Count() * totalsets) / max((uint16)1, v->cargo_cap);
  set = min(set, totalsets - 1);

  return in_motion ? group->g.real.loaded[set] : group->g.real.loading[set];
}


static inline void NewVehicleResolver(ResolverObject *res, EngineID engine_type, const Vehicle *v)
{
  res->GetRandomBits = &VehicleGetRandomBits;
  res->GetTriggers   = &VehicleGetTriggers;
  res->SetTriggers   = &VehicleSetTriggers;
  res->GetVariable   = &VehicleGetVariable;
  res->ResolveReal   = &VehicleResolveReal;

  res->u.vehicle.self   = v;
  res->u.vehicle.parent = (v != NULL) ? v->First() : v;

  res->u.vehicle.self_type = engine_type;

  res->info_view = false;

  res->callback        = CBID_NO_CALLBACK;
  res->callback_param1 = 0;
  res->callback_param2 = 0;
  res->last_value      = 0;
  res->trigger         = 0;
  res->reseed          = 0;
  res->count           = 0;

  const Engine *e = GetEngine(engine_type);
  res->grffile         = (e != NULL ? e->grffile : NULL);
}


static const SpriteGroup *GetVehicleSpriteGroup(EngineID engine, const Vehicle *v, bool use_cache = true)
{
  const SpriteGroup *group;
  CargoID cargo;

  if (v == NULL) {
    cargo = CT_PURCHASE;
  } else {
    cargo = v->cargo_type;

    if (v->type == VEH_TRAIN) {
      /* We always use cached value, except for callbacks because the override spriteset
       * to use may be different than the one cached. It happens for callback 0x15 (refit engine),
       * as v->cargo_type is temporary changed to the new type */
      group = use_cache ? v->u.rail.cached_override : GetWagonOverrideSpriteSet(v->engine_type, v->cargo_type, v->u.rail.first_engine);
      if (group != NULL) return group;
    }
  }

  const Engine *e = GetEngine(engine);

  group = e->group[cargo];
  if (group != NULL) return group;

  /* Fall back to the default set if the selected cargo type is not defined */
  return e->group[CT_DEFAULT];
}


SpriteID GetCustomEngineSprite(EngineID engine, const Vehicle *v, Direction direction)
{
  const SpriteGroup *group;
  ResolverObject object;

  NewVehicleResolver(&object, engine, v);

  group = Resolve(GetVehicleSpriteGroup(engine, v), &object);
  if (group == NULL || group->type != SGT_RESULT || group->g.result.num_sprites == 0) return 0;

  return group->g.result.sprite + (direction % group->g.result.num_sprites);
}


SpriteID GetRotorOverrideSprite(EngineID engine, const Vehicle *v, bool info_view)
{
  const Engine *e = GetEngine(engine);

  /* Only valid for helicopters */
  assert(e->type == VEH_AIRCRAFT);
  assert(!(e->u.air.subtype & AIR_CTOL));

  ResolverObject object;

  NewVehicleResolver(&object, engine, v);

  object.info_view = info_view;

  const SpriteGroup *group = GetWagonOverrideSpriteSet(engine, CT_DEFAULT, engine);
  group = Resolve(group, &object);

  if (group == NULL || group->type != SGT_RESULT || group->g.result.num_sprites == 0) return 0;

  if (v == NULL) return group->g.result.sprite;

  return group->g.result.sprite + (info_view ? 0 : (v->Next()->Next()->u.air.state % group->g.result.num_sprites));
}


bool UsesWagonOverride(const Vehicle* v)
{
  assert(v->type == VEH_TRAIN);
  return v->u.rail.cached_override != NULL;
}

uint16 GetVehicleCallback(CallbackID callback, uint32 param1, uint32 param2, EngineID engine, const Vehicle *v)
{
  const SpriteGroup *group;
  ResolverObject object;

  NewVehicleResolver(&object, engine, v);

  object.callback        = callback;
  object.callback_param1 = param1;
  object.callback_param2 = param2;

  group = Resolve(GetVehicleSpriteGroup(engine, v, false), &object);
  if (group == NULL || group->type != SGT_CALLBACK) return CALLBACK_FAILED;

  return group->g.callback.result;
}

uint16 GetVehicleCallbackParent(CallbackID callback, uint32 param1, uint32 param2, EngineID engine, const Vehicle *v, const Vehicle *parent)
{
  const SpriteGroup *group;
  ResolverObject object;

  NewVehicleResolver(&object, engine, v);

  object.callback        = callback;
  object.callback_param1 = param1;
  object.callback_param2 = param2;

  object.u.vehicle.parent = parent;

  group = Resolve(GetVehicleSpriteGroup(engine, v, false), &object);
  if (group == NULL || group->type != SGT_CALLBACK) return CALLBACK_FAILED;

  return group->g.callback.result;
}


/* Callback 36 handlers */
uint GetVehicleProperty(const Vehicle *v, uint8 property, uint orig_value)
{
  uint16 callback = GetVehicleCallback(CBID_VEHICLE_MODIFY_PROPERTY, property, 0, v->engine_type, v);
  if (callback != CALLBACK_FAILED) return callback;

  return orig_value;
}


uint GetEngineProperty(EngineID engine, uint8 property, uint orig_value)
{
  uint16 callback = GetVehicleCallback(CBID_VEHICLE_MODIFY_PROPERTY, property, 0, engine, NULL);
  if (callback != CALLBACK_FAILED) return callback;

  return orig_value;
}


static void DoTriggerVehicle(Vehicle *v, VehicleTrigger trigger, byte base_random_bits, bool first)
{
  const SpriteGroup *group;
  ResolverObject object;
  byte new_random_bits;

  /* We can't trigger a non-existent vehicle... */
  assert(v != NULL);

  NewVehicleResolver(&object, v->engine_type, v);
  object.callback = CBID_RANDOM_TRIGGER;
  object.trigger = trigger;

  group = Resolve(GetVehicleSpriteGroup(v->engine_type, v), &object);
  if (group == NULL) return;

  new_random_bits = Random();
  v->random_bits &= ~object.reseed;
  v->random_bits |= (first ? new_random_bits : base_random_bits) & object.reseed;

  switch (trigger) {
    case VEHICLE_TRIGGER_NEW_CARGO:
      /* All vehicles in chain get ANY_NEW_CARGO trigger now.
       * So we call it for the first one and they will recurse. */
      /* Indexing part of vehicle random bits needs to be
       * same for all triggered vehicles in the chain (to get
       * all the random-cargo wagons carry the same cargo,
       * i.e.), so we give them all the NEW_CARGO triggered
       * vehicle's portion of random bits. */
      assert(first);
      DoTriggerVehicle(v->First(), VEHICLE_TRIGGER_ANY_NEW_CARGO, new_random_bits, false);
      break;

    case VEHICLE_TRIGGER_DEPOT:
      /* We now trigger the next vehicle in chain recursively.
       * The random bits portions may be different for each
       * vehicle in chain. */
      if (v->Next() != NULL) DoTriggerVehicle(v->Next(), trigger, 0, true);
      break;

    case VEHICLE_TRIGGER_EMPTY:
      /* We now trigger the next vehicle in chain
       * recursively.  The random bits portions must be same
       * for each vehicle in chain, so we give them all
       * first chained vehicle's portion of random bits. */
      if (v->Next() != NULL) DoTriggerVehicle(v->Next(), trigger, first ? new_random_bits : base_random_bits, false);
      break;

    case VEHICLE_TRIGGER_ANY_NEW_CARGO:
      /* Now pass the trigger recursively to the next vehicle
       * in chain. */
      assert(!first);
      if (v->Next() != NULL) DoTriggerVehicle(v->Next(), VEHICLE_TRIGGER_ANY_NEW_CARGO, base_random_bits, false);
      break;

    case VEHICLE_TRIGGER_CALLBACK_32:
      /* Do not do any recursion */
      break;
  }
}

void TriggerVehicle(Vehicle *v, VehicleTrigger trigger)
{
  if (trigger == VEHICLE_TRIGGER_DEPOT) {
    /* store that the vehicle entered a depot this tick */
    VehicleEnteredDepotThisTick(v);
  }

  DoTriggerVehicle(v, trigger, 0, true);
}

/* Functions for changing the order of vehicle purchase lists
 * This is currently only implemented for rail vehicles. */

uint ListPositionOfEngine(EngineID engine)
{
  const Engine *e = GetEngine(engine);
  if (e->grffile == NULL) return e->list_position;

  /* Crude sorting to group by GRF ID */
  return (e->grffile->grfid * 256) + e->list_position;
}

struct ListOrderChange {
  EngineID engine;
  EngineID target;
};

static SmallVector<ListOrderChange, 16> _list_order_changes;

void AlterVehicleListOrder(EngineID engine, EngineID target)
{
  /* Add the list order change to a queue */
  ListOrderChange *loc = _list_order_changes.Append();
  loc->engine = engine;
  loc->target = target;
}

void CommitVehicleListOrderChanges()
{
  /* List position to Engine map */
  typedef SmallMap<uint16, Engine *, 16> ListPositionMap;
  ListPositionMap lptr_map;

  const ListOrderChange *end = _list_order_changes.End();
  for (const ListOrderChange *it = _list_order_changes.Begin(); it != end; ++it) {
    EngineID engine = it->engine;
    EngineID target = it->target;

    if (engine == target) continue;

    Engine *source_e = GetEngine(engine);
    Engine *target_e = NULL;

    /* Populate map with current list positions */
    Engine *e;
    FOR_ALL_ENGINES_OF_TYPE(e, source_e->type) {
      if (!_settings_game.vehicle.dynamic_engines || e->grffile == source_e->grffile) {
        if (e->internal_id == target) target_e = e;
        lptr_map[e->list_position] = e;
      }
    }

    /* std::map sorted by default, SmallMap does not */
    lptr_map.SortByKey();

    /* Get the target position, if it exists */
    if (target_e != NULL) {
      uint16 target_position = target_e->list_position;

      bool moving = false;
      const ListPositionMap::Pair *end = lptr_map.End();
      for (ListPositionMap::Pair *it = lptr_map.Begin(); it != end; ++it) {
        if (it->first == target_position) moving = true;
        if (moving) it->second->list_position++;
      }

      source_e->list_position = target_position;
    }

    lptr_map.Clear();
  }

  /* Clear out the queue */
  _list_order_changes.Reset();
}