oldloader_sl.cpp

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/*
 * This file is part of OpenTTD.
 * 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.
 * 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.
 * 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/>.
 */
 
#include "../stdafx.h"
#include "../town.h"
#include "../industry.h"
#include "../company_func.h"
#include "../aircraft.h"
#include "../roadveh.h"
#include "../ship.h"
#include "../train.h"
#include "../signs_base.h"
#include "../station_base.h"
#include "../subsidy_base.h"
#include "../debug.h"
#include "../depot_base.h"
#include "../timer/timer_game_calendar.h"
#include "../timer/timer_game_calendar.h"
#include "../vehicle_func.h"
#include "../effectvehicle_base.h"
#include "../engine_func.h"
#include "../company_base.h"
#include "../disaster_vehicle.h"
#include "../timer/timer.h"
#include "../timer/timer_game_tick.h"
#include "../timer/timer_game_calendar.h"
#include "saveload_internal.h"
#include "oldloader.h"
 
#include "table/strings.h"
#include "../table/engines.h"
#include "../table/townname.h"
 
#include "../safeguards.h"
 
static bool _read_ttdpatch_flags;    
static uint16_t _old_extra_chunk_nums; 
 
void FixOldMapArray()
{
  /* TTO/TTD/TTDP savegames could have buoys at tile 0
   * (without assigned station struct) */
  MakeSea(0);
}
 
static void FixTTDMapArray()
{
  for (auto tile : Map::Iterate()) {
    switch (GetTileType(tile)) {
      case MP_STATION:
        tile.m4() = 0; // We do not understand this TTDP station mapping (yet)
        switch (tile.m5()) {
          /* We have drive through stops at a totally different place */
          case 0x53: case 0x54: tile.m5() += 170 - 0x53; break; // Bus drive through
          case 0x57: case 0x58: tile.m5() += 168 - 0x57; break; // Truck drive through
          case 0x55: case 0x56: tile.m5() += 170 - 0x55; break; // Bus tram stop
          case 0x59: case 0x5A: tile.m5() += 168 - 0x59; break; // Truck tram stop
          default: break;
        }
        break;
 
      case MP_RAILWAY:
        /* We save presignals different from TTDPatch, convert them */
        if (GB(tile.m5(), 6, 2) == 1) { // RAIL_TILE_SIGNALS
          /* This byte is always zero in TTD for this type of tile */
          if (tile.m4()) { // Convert the presignals to our own format
            tile.m4() = (tile.m4() >> 1) & 7;
          }
        }
        /* TTDPatch stores PBS things in L6 and all elsewhere; so we'll just
         * clear it for ourselves and let OTTD's rebuild PBS itself */
        tile.m4() &= 0xF; // Only keep the lower four bits; upper four is PBS
        break;
 
      case MP_WATER:
        /* if water class == 3, make river there */
        if (GB(tile.m3(), 0, 2) == 3) {
          SetTileType(tile, MP_WATER);
          SetTileOwner(tile, OWNER_WATER);
          tile.m2() = 0;
          tile.m3() = 2; // WATER_CLASS_RIVER
          tile.m4() = Random();
          tile.m5() = 0;
        }
        break;
 
      default:
        break;
    }
  }
 
  FixOldMapArray();
}
 
static void FixTTDDepots()
{
  for (const Depot *d : Depot::Iterate(252)) {
    if (!IsDepotTile(d->xy) || GetDepotIndex(d->xy) != d->index) {
      delete d;
    }
  }
}
static void FixTTDDepots() {…}
 
static uint32_t RemapOldTownName(uint32_t townnameparts, uint8_t old_town_name_type)
{
  auto fix_num = [](uint32_t i, uint32_t n, uint8_t s) -> uint32_t {
    return ((i << 16) / n + 1) << s;
  };
 
  switch (old_town_name_type) {
    case 0: case 3: // English, American
      /* Already OK */
      return townnameparts;
 
    case 1: // French
      /* For some reason 86 needs to be subtracted from townnameparts
       * 0000 0000 0000 0000 0000 0000 1111 1111 */
      return fix_num(townnameparts - 86, lengthof(_name_french_real), 0);
 
    case 2: // German
      Debug(misc, 0, "German Townnames are buggy ({})", townnameparts);
      return townnameparts;
 
    case 4: // Latin-American
      /* 0000 0000 0000 0000 0000 0000 1111 1111 */
      return fix_num(townnameparts, lengthof(_name_spanish_real), 0);
 
    case 5: // Silly
      /* NUM_SILLY_1 - lower 16 bits
       * NUM_SILLY_2 - upper 16 bits without leading 1 (first 8 bytes)
       * 1000 0000 2222 2222 0000 0000 1111 1111 */
      return fix_num(townnameparts, lengthof(_name_silly_1), 0) | fix_num(GB(townnameparts, 16, 8), lengthof(_name_silly_2), 16);
  }
  return 0;
}
 
static void FixOldTowns()
{
  /* Convert town-names if needed */
  for (Town *town : Town::Iterate()) {
    if (IsInsideMM(town->townnametype, 0x20C1, 0x20C3)) {
      town->townnametype = SPECSTR_TOWNNAME_START + _settings_game.game_creation.town_name;
      town->townnameparts = RemapOldTownName(town->townnameparts, _settings_game.game_creation.town_name);
    }
  }
}
 
void FixOldVehicles(LoadgameState &ls)
{
  for (Vehicle *v : Vehicle::Iterate()) {
    if ((size_t)v->next == 0xFFFF) {
      v->next = nullptr;
    } else {
      v->next = Vehicle::GetIfValid((size_t)v->next);
    }
 
    /* For some reason we need to correct for this */
    switch (v->spritenum) {
      case 0xfd: break;
      case 0xff: v->spritenum = 0xfe; break;
      default:   v->spritenum >>= 1; break;
    }
 
    /* Vehicle-subtype is different in TTD(Patch) */
    if (v->type == VEH_EFFECT) v->subtype = v->subtype >> 1;
 
    v->name = CopyFromOldName(ls.vehicle_names[v->index.base()]);
 
    /* We haven't used this bit for stations for ages */
    if (v->type == VEH_ROAD) {
      RoadVehicle *rv = RoadVehicle::From(v);
      if (rv->state != RVSB_IN_DEPOT && rv->state != RVSB_WORMHOLE) {
        ClrBit(rv->state, 2);
        Tile tile(rv->tile);
        if (IsTileType(tile, MP_STATION) && tile.m5() >= 168) {
          /* Update the vehicle's road state to show we're in a drive through road stop. */
          SetBit(rv->state, RVS_IN_DT_ROAD_STOP);
        }
      }
    }
 
    /* The subtype should be 0, but it sometimes isn't :( */
    if (v->type == VEH_ROAD || v->type == VEH_SHIP) v->subtype = 0;
 
    /* Sometimes primary vehicles would have a nothing (invalid) order
     * or vehicles that could not have an order would still have a
     * (loading) order which causes assertions and the like later on.
     */
    if (!IsCompanyBuildableVehicleType(v) ||
        (v->IsPrimaryVehicle() && v->current_order.IsType(OT_NOTHING))) {
      v->current_order.MakeDummy();
    }
 
    /* Shared orders are fixed in AfterLoadVehicles now */
  }
}
void FixOldVehicles(LoadgameState &ls) {…};
 
static bool FixTTOMapArray()
{
  for (auto tile : Map::Iterate()) {
    TileType tt = GetTileType(tile);
    if (tt == 11) {
      /* TTO has a different way of storing monorail.
       * Instead of using bits in m3 it uses a different tile type. */
      tile.m3() = 1; // rail type = monorail (in TTD)
      SetTileType(tile, MP_RAILWAY);
      tile.m2() = 1; // set monorail ground to RAIL_GROUND_GRASS
      tt = MP_RAILWAY;
    }
 
    switch (tt) {
      case MP_CLEAR:
        break;
 
      case MP_RAILWAY:
        switch (GB(tile.m5(), 6, 2)) {
          case 0: // RAIL_TILE_NORMAL
            break;
          case 1: // RAIL_TILE_SIGNALS
            tile.m4() = (~tile.m5() & 1) << 2;        // signal variant (present only in OTTD)
            SB(tile.m2(), 6, 2, GB(tile.m5(), 3, 2)); // signal status
            tile.m3() |= 0xC0;                       // both signals are present
            tile.m5() = HasBit(tile.m5(), 5) ? 2 : 1; // track direction (only X or Y)
            tile.m5() |= 0x40;                       // RAIL_TILE_SIGNALS
            break;
          case 3: // RAIL_TILE_DEPOT
            tile.m2() = 0;
            break;
          default:
            return false;
        }
        break;
 
      case MP_ROAD: // road (depot) or level crossing
        switch (GB(tile.m5(), 4, 4)) {
          case 0: // ROAD_TILE_NORMAL
            if (tile.m2() == 4) tile.m2() = 5; // 'small trees' -> ROADSIDE_TREES
            break;
          case 1: // ROAD_TILE_CROSSING (there aren't monorail crossings in TTO)
            tile.m3() = tile.m1(); // set owner of road = owner of rail
            break;
          case 2: // ROAD_TILE_DEPOT
            break;
          default:
            return false;
        }
        break;
 
      case MP_HOUSE:
        tile.m3() = tile.m2() & 0xC0;    // construction stage
        tile.m2() &= 0x3F;               // building type
        if (tile.m2() >= 5) tile.m2()++; // skip "large office block on snow"
        break;
 
      case MP_TREES:
        tile.m3() = GB(tile.m5(), 3, 3); // type of trees
        tile.m5() &= 0xC7;               // number of trees and growth status
        break;
 
      case MP_STATION:
        tile.m3() = (tile.m5() >= 0x08 && tile.m5() <= 0x0F) ? 1 : 0; // monorail -> 1, others 0 (rail, road, airport, dock)
        if (tile.m5() >= 8) tile.m5() -= 8; // shift for monorail
        if (tile.m5() >= 0x42) tile.m5()++; // skip heliport
        break;
 
      case MP_WATER:
        tile.m3() = tile.m2() = 0;
        break;
 
      case MP_VOID:
        tile.m2() = tile.m3() = tile.m5() = 0;
        break;
 
      case MP_INDUSTRY:
        tile.m3() = 0;
        switch (tile.m5()) {
          case 0x24: // farm silo
            tile.m5() = 0x25;
            break;
          case 0x25: case 0x27: // farm
          case 0x28: case 0x29: case 0x2A: case 0x2B: // factory
            tile.m5()--;
            break;
          default:
            if (tile.m5() >= 0x2C) tile.m5() += 3; // iron ore mine, steel mill or bank
            break;
        }
        break;
 
      case MP_TUNNELBRIDGE:
        if (HasBit(tile.m5(), 7)) { // bridge
          uint8_t m5 = tile.m5();
          tile.m5() = m5 & 0xE1; // copy bits 7..5, 1
          if (GB(m5, 1, 2) == 1) tile.m5() |= 0x02; // road bridge
          if (GB(m5, 1, 2) == 3) tile.m2() |= 0xA0; // monorail bridge -> tubular, steel bridge
          if (!HasBit(m5, 6)) { // bridge head
            tile.m3() = (GB(m5, 1, 2) == 3) ? 1 : 0; // track subtype (1 for monorail, 0 for others)
          } else { // middle bridge part
            tile.m3() = HasBit(m5, 2) ? 0x10 : 0;  // track subtype on bridge
            if (GB(m5, 3, 2) == 3) tile.m3() |= 1; // track subtype under bridge
            if (GB(m5, 3, 2) == 1) tile.m5() |= 0x08; // set for road/water under (0 for rail/clear)
          }
        } else { // tunnel entrance/exit
          tile.m2() = 0;
          tile.m3() = HasBit(tile.m5(), 3); // monorail
          tile.m5() &= HasBit(tile.m5(), 3) ? 0x03 : 0x07 ; // direction, transport type (== 0 for rail)
        }
        break;
 
      case MP_OBJECT:
        tile.m2() = 0;
        tile.m3() = 0;
        break;
 
      default:
        return false;
 
    }
  }
 
  FixOldMapArray();
 
  return true;
}
 
static Engine *_old_engines;
 
static bool FixTTOEngines()
{
  using OldEngineID = uint8_t;
  static const OldEngineID ttd_to_tto[] = {
      0, 255, 255, 255, 255, 255, 255, 255,   5,   7,   8,   9,  10,  11,  12,  13,
    255, 255, 255, 255, 255, 255,  15,  16,  17,  18,  19,  20,  21,  22,  23,  24,
    25,   26,  27,  29,  28,  30, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255,  31, 255,  32,  33,  34,  35,  36,  37,  38,
     39,  40,  41,  42, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255,  44,  45,  46, 255, 255, 255, 255,  47,  48, 255,  49,  50,
    255, 255, 255, 255,  51,  52, 255,  53,  54, 255,  55,  56, 255,  57,  59, 255,
     58,  60, 255,  61,  62, 255,  63,  64, 255,  65,  66, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255,  67,  68,  69,  70,
     71, 255, 255,  76,  77, 255, 255,  78,  79,  80,  81,  82,  83,  84,  85,  86,
     87,  88,  89,  90,  91,  92,  93,  94,  95,  96,  97,  98,  99, 100, 101, 255,
    255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 102, 255, 255
  };
 
  static const OldEngineID tto_to_ttd[] = {
      0,   0,   8,   8,   8,   8,   8,   9,  10,  11,  12,  13,  14,  15,  15,  22,
     23,  24,  25,  26,  27,  29,  28,  30,  31,  32,  33,  34,  35,  36,  37,  55,
     57,  59,  58,  60,  61,  62,  63,  64,  65,  66,  67, 116, 116, 117, 118, 123,
    124, 126, 127, 132, 133, 135, 136, 138, 139, 141, 142, 144, 145, 147, 148, 150,
    151, 153, 154, 204, 205, 206, 207, 208, 211, 212, 211, 212, 211, 212, 215, 216,
    217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232,
    233, 234, 235, 236, 237, 238, 253
  };
 
  for (Vehicle *v : Vehicle::Iterate()) {
    if (v->engine_type >= lengthof(tto_to_ttd)) return false;
    v->engine_type = static_cast<EngineID>(tto_to_ttd[v->engine_type.base()]);
  }
 
  /* Load the default engine set. Many of them will be overridden later */
  {
    EngineID j = EngineID::Begin();
    for (uint16_t i = 0; i < lengthof(_orig_rail_vehicle_info); ++i, ++j) new (GetTempDataEngine(j)) Engine(VEH_TRAIN, i);
    for (uint16_t i = 0; i < lengthof(_orig_road_vehicle_info); ++i, ++j) new (GetTempDataEngine(j)) Engine(VEH_ROAD, i);
    for (uint16_t i = 0; i < lengthof(_orig_ship_vehicle_info); ++i, ++j) new (GetTempDataEngine(j)) Engine(VEH_SHIP, i);
    for (uint16_t i = 0; i < lengthof(_orig_aircraft_vehicle_info); ++i, ++j) new (GetTempDataEngine(j)) Engine(VEH_AIRCRAFT, i);
  }
 
  TimerGameCalendar::Date aging_date = std::min(TimerGameCalendar::date + CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR, TimerGameCalendar::ConvertYMDToDate(TimerGameCalendar::Year{2050}, 0, 1));
  TimerGameCalendar::YearMonthDay aging_ymd = TimerGameCalendar::ConvertDateToYMD(aging_date);
 
  for (EngineID i = EngineID::Begin(); i < 256; ++i) {
    OldEngineID oi = ttd_to_tto[i.base()];
    Engine *e = GetTempDataEngine(i);
 
    if (oi == 255) {
      /* Default engine is used */
      TimerGameCalendar::date += CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR;
      StartupOneEngine(e, aging_ymd, 0);
      CalcEngineReliability(e, false);
      e->intro_date -= CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR;
      TimerGameCalendar::date -= CalendarTime::DAYS_TILL_ORIGINAL_BASE_YEAR;
 
      /* Make sure for example monorail and maglev are available when they should be */
      if (TimerGameCalendar::date >= e->intro_date && e->info.climates.Test(LandscapeType::Temperate)) {
        e->flags.Set(EngineFlag::Available);
        e->company_avail.Set();
        e->age = TimerGameCalendar::date > e->intro_date ? (TimerGameCalendar::date - e->intro_date).base() / 30 : 0;
      }
    } else {
      /* Using data from TTO savegame */
      Engine *oe = &_old_engines[oi];
 
      e->intro_date          = oe->intro_date;
      e->age                 = oe->age;
      e->reliability         = oe->reliability;
      e->reliability_spd_dec = oe->reliability_spd_dec;
      e->reliability_start   = oe->reliability_start;
      e->reliability_max     = oe->reliability_max;
      e->reliability_final   = oe->reliability_final;
      e->duration_phase_1    = oe->duration_phase_1;
      e->duration_phase_2    = oe->duration_phase_2;
      e->duration_phase_3    = oe->duration_phase_3;
      e->flags               = oe->flags;
 
      e->company_avail = CompanyMask{};
 
      /* One or more engines were remapped to this one. Make this engine available
       * if at least one of them was available. */
      for (uint j = 0; j < lengthof(tto_to_ttd); j++) {
        if (tto_to_ttd[j] == i && _old_engines[j].company_avail.Any()) {
          e->company_avail.Set();
          e->flags.Set(EngineFlag::Available);
          break;
        }
      }
 
      e->info.climates = LandscapeType::Temperate;
    }
 
    e->preview_company = CompanyID::Invalid();
    e->preview_asked.Set();
    e->preview_wait = 0;
    e->name = std::string{};
  }
 
  return true;
}
static bool FixTTOEngines() {…}
 
static void FixTTOCompanies()
{
  for (Company *c : Company::Iterate()) {
    c->cur_economy.company_value = CalculateCompanyValue(c); // company value history is zeroed
  }
}
 
static inline Colours RemapTTOColour(Colours tto)
{
  static const Colours tto_colour_remap[] = {
    COLOUR_DARK_BLUE,  COLOUR_GREY,       COLOUR_YELLOW,     COLOUR_RED,
    COLOUR_PURPLE,     COLOUR_DARK_GREEN, COLOUR_ORANGE,     COLOUR_PALE_GREEN,
    COLOUR_BLUE,       COLOUR_GREEN,      COLOUR_CREAM,      COLOUR_BROWN,
    COLOUR_WHITE,      COLOUR_LIGHT_BLUE, COLOUR_MAUVE,      COLOUR_PINK
  };
 
  if (static_cast<size_t>(tto) >= std::size(tto_colour_remap)) return COLOUR_GREY; // this shouldn't happen
 
  return tto_colour_remap[tto];
}
static inline Colours RemapTTOColour(Colours tto) {…}
 
static inline uint RemapTownIndex(uint x)
{
  return _savegame_type == SGT_TTO ? (x - 0x264) / 78 : (x - 0x264) / 94;
}
 
static inline uint RemapOrderIndex(uint x)
{
  return _savegame_type == SGT_TTO ? (x - 0x1AC4) / 2 : (x - 0x1C18) / 2;
}
 
extern std::vector<TileIndex> _animated_tiles;
extern TimeoutTimer<TimerGameTick> _new_competitor_timeout;
extern std::unique_ptr<std::string[]> _old_name_array;
 
static uint32_t _old_town_index;
static uint16_t _old_string_id;
static uint16_t _old_string_id_2;
 
static void ClearOldMap3(TileIndex t)
{
  Tile tile(t);
  tile.m3() = 0;
  tile.m4() = 0;
}
 
static Town *RemapTown(TileIndex fallback)
{
  /* In some cases depots, industries and stations could refer to a missing town. */
  Town *t = Town::GetIfValid(RemapTownIndex(_old_town_index));
  if (t == nullptr) {
    /* In case the town that was referred to does not exist, find the closest.
     * However, this needs the kd-tree to be present. */
    RebuildTownKdtree();
    t = CalcClosestTownFromTile(fallback);
  }
  return t;
}
 
static void ReadTTDPatchFlags(LoadgameState &ls)
{
  if (_read_ttdpatch_flags) return;
 
  _read_ttdpatch_flags = true;
 
  /* Set default values */
  ls.vehicle_multiplier = 1;
  _ttdp_version = 0;
  _old_extra_chunk_nums = 0;
  _bump_assert_value = 0;
 
  if (_savegame_type == SGT_TTO) {
    ls.vehicle_names.resize(800);
    return;
  }
 
  /* TTDPatch misuses old map3 (now m3/m4) for flags.. read them! */
  ls.vehicle_multiplier = Tile(0).m3();
  /* Somehow.... there was an error in some savegames, so 0 becomes 1
   * and 1 becomes 2. The rest of the values are okay */
  if (ls.vehicle_multiplier < 2) ls.vehicle_multiplier++;
 
  ls.vehicle_names.resize(ls.vehicle_multiplier * 850);
 
  /* TTDPatch increases the Vehicle-part in the middle of the game,
   * so if the multiplier is anything else but 1, the assert fails..
   * bump the assert value so it doesn't!
   * (1 multiplier == 850 vehicles
   * 1 vehicle   == 128 bytes */
  _bump_assert_value = (ls.vehicle_multiplier - 1) * 850 * 128;
 
  /* The first 17 bytes are used by TTDP1, which translates to the first 9 m3s and first 8 m4s. */
  for (TileIndex i{}; i <= 8; i++) { // check tile 0, too
    Tile tile(i);
    if (tile.m3() != 0 || (i != 8 && tile.m4() != 0)) _savegame_type = SGT_TTDP1;
  }
 
  /* Check if we have a modern TTDPatch savegame (has extra data all around) */
  Tile ttdp2_header_first(Map::Size() - 3);
  Tile ttdp2_header_second(Map::Size() - 2);
  if (ttdp2_header_first.m3() == 'T' && ttdp2_header_first.m4() == 'T' &&
    ttdp2_header_second.m3() == 'D' && ttdp2_header_second.m4() == 'p') {
    _savegame_type = SGT_TTDP2;
  }
 
  Tile extra_chunk_tile = Tile(_savegame_type == SGT_TTDP2 ? Map::Size() - 1 : 1);
  _old_extra_chunk_nums = extra_chunk_tile.m3() | extra_chunk_tile.m4() << 8;
 
  /* Clean the misused places */
  for (TileIndex i{}; i < 9; i++) ClearOldMap3(i);
  for (TileIndex i = TileXY(0, Map::MaxY()); i < Map::Size(); i++) ClearOldMap3(i);
 
  if (_savegame_type == SGT_TTDP2) Debug(oldloader, 2, "Found TTDPatch game");
 
  Debug(oldloader, 3, "Vehicle-multiplier is set to {} ({} vehicles)", ls.vehicle_multiplier, ls.vehicle_multiplier * 850);
}
 
static std::array<Town::SuppliedHistory, 2> _old_pass_supplied{};
static std::array<Town::SuppliedHistory, 2> _old_mail_supplied{};
 
static const OldChunks town_chunk[] = {
  OCL_SVAR(   OC_TILE, Town, xy ),
  OCL_NULL( 2 ),         
  OCL_SVAR( OC_UINT16, Town, townnametype ),
  OCL_SVAR( OC_UINT32, Town, townnameparts ),
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Town, grow_counter ),
  OCL_NULL( 1 ),         
  OCL_NULL( 4 ),         
  OCL_NULL( 2 ),         
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, Town, flags ),
  OCL_NULL( 10 ),        
 
  OCL_SVAR( OC_INT16, Town, ratings[0] ),
  OCL_SVAR( OC_INT16, Town, ratings[1] ),
  OCL_SVAR( OC_INT16, Town, ratings[2] ),
  OCL_SVAR( OC_INT16, Town, ratings[3] ),
  OCL_SVAR( OC_INT16, Town, ratings[4] ),
  OCL_SVAR( OC_INT16, Town, ratings[5] ),
  OCL_SVAR( OC_INT16, Town, ratings[6] ),
  OCL_SVAR( OC_INT16, Town, ratings[7] ),
 
  OCL_SVAR( OC_FILE_U32 | OC_VAR_U16, Town, have_ratings ),
  OCL_SVAR( OC_FILE_U32 | OC_VAR_U16, Town, statues ),
  OCL_NULL( 2 ),         
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Town, time_until_rebuild ),
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Town, growth_rate ),
 
  /* Slots 0 and 2 are passengers and mail respectively for old saves. */
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_pass_supplied[THIS_MONTH].production ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_mail_supplied[THIS_MONTH].production ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_pass_supplied[THIS_MONTH].transported ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_mail_supplied[THIS_MONTH].transported ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_pass_supplied[LAST_MONTH].production ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_mail_supplied[LAST_MONTH].production ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_pass_supplied[LAST_MONTH].transported ),
  OCL_VAR( OC_FILE_U16 | OC_VAR_U32, 1, &_old_mail_supplied[LAST_MONTH].transported ),
 
  OCL_NULL( 2 ),         
 
  OCL_SVAR( OC_TTD | OC_UINT16, Town, received[TAE_FOOD].new_act ),
  OCL_SVAR( OC_TTD | OC_UINT16, Town, received[TAE_WATER].new_act ),
  OCL_SVAR( OC_TTD | OC_UINT16, Town, received[TAE_FOOD].old_act ),
  OCL_SVAR( OC_TTD | OC_UINT16, Town, received[TAE_WATER].old_act ),
 
  OCL_SVAR(  OC_UINT8, Town, road_build_months ),
  OCL_SVAR(  OC_UINT8, Town, fund_buildings_months ),
 
  OCL_CNULL( OC_TTD, 8 ),         
 
  OCL_END()
};
 
static bool LoadOldTown(LoadgameState &ls, int num)
{
  Town *t = new (TownID(num)) Town();
  if (!LoadChunk(ls, t, town_chunk)) return false;
 
  if (t->xy != 0) {
    if (_savegame_type == SGT_TTO) {
      /* 0x10B6 is auto-generated name, others are custom names */
      t->townnametype = t->townnametype == 0x10B6 ? 0x20C1 : t->townnametype + 0x2A00;
    }
    /* Passengers and mail were always treated as slots 0 and 2 in older saves. */
    auto &pass = t->supplied.emplace_back(0);
    pass.history[LAST_MONTH] = _old_pass_supplied[LAST_MONTH];
    pass.history[THIS_MONTH] = _old_pass_supplied[THIS_MONTH];
    auto &mail = t->supplied.emplace_back(2);
    mail.history[LAST_MONTH] = _old_mail_supplied[LAST_MONTH];
    mail.history[THIS_MONTH] = _old_mail_supplied[THIS_MONTH];
  } else {
    delete t;
  }
 
  return true;
}
 
static uint16_t _old_order;
static const OldChunks order_chunk[] = {
  OCL_VAR ( OC_UINT16,   1, &_old_order ),
  OCL_END()
};
 
static bool LoadOldOrder(LoadgameState &ls, int num)
{
  if (!LoadChunk(ls, nullptr, order_chunk)) return false;
 
  OldOrderSaveLoadItem &o = AllocateOldOrder(num);
  o.order.AssignOrder(UnpackOldOrder(_old_order));
 
  if (!o.order.IsType(OT_NOTHING) && num > 0) {
    /* Relink the orders to each other (in the orders for one vehicle are behind each other,
     * with an invalid order (OT_NOTHING) as indication that it is the last order */
    OldOrderSaveLoadItem *prev = GetOldOrder(num + 1 - 1);
    if (prev != nullptr) prev->next = num + 1; // next is 1-based.
  }
 
  return true;
}
 
static bool LoadOldAnimTileList(LoadgameState &ls, int)
{
  TileIndex anim_list[256];
  const OldChunks anim_chunk[] = {
    OCL_VAR (   OC_TILE, 256, anim_list ),
    OCL_END ()
  };
 
  if (!LoadChunk(ls, nullptr, anim_chunk)) return false;
 
  /* The first zero in the loaded array indicates the end of the list. */
  for (int i = 0; i < 256; i++) {
    if (anim_list[i] == 0) break;
    _animated_tiles.push_back(anim_list[i]);
  }
 
  return true;
}
 
static const OldChunks depot_chunk[] = {
  OCL_SVAR(   OC_TILE, Depot, xy ),
  OCL_VAR ( OC_UINT32,                1, &_old_town_index ),
  OCL_END()
};
 
static bool LoadOldDepot(LoadgameState &ls, int num)
{
  Depot *d = new (DepotID(num)) Depot();
  if (!LoadChunk(ls, d, depot_chunk)) return false;
 
  if (d->xy != 0) {
    d->town = RemapTown(d->xy);
  } else {
    delete d;
  }
 
  return true;
}
 
static StationID _current_station_id;
static uint16_t _waiting_acceptance;
static uint8_t  _cargo_source;
static uint8_t  _cargo_periods;
 
static const OldChunks goods_chunk[] = {
  OCL_VAR ( OC_UINT16, 1,          &_waiting_acceptance ),
  OCL_SVAR(  OC_UINT8, GoodsEntry, time_since_pickup ),
  OCL_SVAR(  OC_UINT8, GoodsEntry, rating ),
  OCL_VAR (  OC_UINT8, 1,          &_cargo_source ),
  OCL_VAR (  OC_UINT8, 1,          &_cargo_periods ),
  OCL_SVAR(  OC_UINT8, GoodsEntry, last_speed ),
  OCL_SVAR(  OC_UINT8, GoodsEntry, last_age ),
 
  OCL_END()
};
 
static bool LoadOldGood(LoadgameState &ls, int num)
{
  /* for TTO games, 12th (num == 11) goods entry is created in the Station constructor */
  if (_savegame_type == SGT_TTO && num == 11) return true;
 
  Station *st = Station::Get(_current_station_id);
  GoodsEntry *ge = &st->goods[num];
 
  if (!LoadChunk(ls, ge, goods_chunk)) return false;
 
  ge->status.Set(GoodsEntry::State::Acceptance, HasBit(_waiting_acceptance, 15));
  ge->status.Set(GoodsEntry::State::Rating, _cargo_source != 0xFF);
  if (GB(_waiting_acceptance, 0, 12) != 0 && CargoPacket::CanAllocateItem()) {
    ge->GetOrCreateData().cargo.Append(new CargoPacket(GB(_waiting_acceptance, 0, 12), _cargo_periods, (_cargo_source == 0xFF) ? StationID::Invalid() : StationID{_cargo_source}, INVALID_TILE, 0),
        StationID::Invalid());
  }
 
  return true;
}
 
static const OldChunks station_chunk[] = {
  OCL_SVAR(   OC_TILE, Station, xy ),
  OCL_VAR ( OC_UINT32,   1, &_old_town_index ),
 
  OCL_NULL( 4 ), 
  OCL_SVAR(   OC_TILE, Station, train_station.tile ),
  OCL_SVAR(   OC_TILE, Station, airport.tile ),
  OCL_NULL( 2 ), 
  OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Station, train_station.w ),
 
  OCL_NULL( 1 ),         
  OCL_NULL( 2 ),         
 
  OCL_VAR ( OC_UINT16,   1, &_old_string_id ),
 
  OCL_NULL( 4 ),         
 
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U8, Station, had_vehicle_of_type ),
 
  OCL_CHUNK( 12, LoadOldGood ),
 
  OCL_SVAR(  OC_UINT8, Station, time_since_load ),
  OCL_SVAR(  OC_UINT8, Station, time_since_unload ),
  OCL_SVAR(  OC_UINT8, Station, delete_ctr ),
  OCL_SVAR(  OC_UINT8, Station, owner ),
  OCL_SVAR(  OC_UINT8, Station, facilities ),
  OCL_SVAR( OC_TTD | OC_UINT8, Station, airport.type ),
  OCL_SVAR( OC_TTO | OC_FILE_U16 | OC_VAR_U64, Station, airport.blocks ),
  OCL_NULL( 3 ),          
  OCL_CNULL( OC_TTD, 1 ), 
  OCL_SVAR( OC_TTD | OC_FILE_U16 | OC_VAR_U64, Station, airport.blocks ),
  OCL_CNULL( OC_TTD, 2 ), 
  OCL_CNULL( OC_TTD, 4 ), 
 
  OCL_END()
};
 
static bool LoadOldStation(LoadgameState &ls, int num)
{
  Station *st = new (StationID(num)) Station();
  _current_station_id = st->index;
 
  if (!LoadChunk(ls, st, station_chunk)) return false;
 
  if (st->xy != 0) {
    st->town = RemapTown(st->xy);
 
    if (_savegame_type == SGT_TTO) {
      if (IsInsideBS(_old_string_id, 0x180F, 32)) {
        st->string_id = STR_SV_STNAME + (_old_string_id - 0x180F); // automatic name
      } else {
        st->string_id = _old_string_id + 0x2800; // custom name
      }
 
      if (st->airport.blocks.Test(AirportBlock{8})) {
        st->airport.type = 1; // large airport
      } else if (st->airport.blocks.Test(AirportBlock{6})) {
        st->airport.type = 3; // oil rig
      } else {
        st->airport.type = 0; // small airport
      }
    } else {
      st->string_id = RemapOldStringID(_old_string_id);
    }
  } else {
    delete st;
  }
 
  return true;
}
 
/* Old save games always have 3 input and 2 output slots per industry. */
static std::array<Industry::AcceptedCargo, INDUSTRY_ORIGINAL_NUM_INPUTS> _old_accepted{};
static std::array<Industry::ProducedCargo, INDUSTRY_ORIGINAL_NUM_OUTPUTS> _old_produced{};
 
static const OldChunks industry_chunk[] = {
  OCL_SVAR(   OC_TILE, Industry, location.tile ),
  OCL_VAR ( OC_UINT32,   1, &_old_town_index ),
  OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Industry, location.w ),
  OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Industry, location.h ),
  OCL_NULL( 2 ),  
 
  OCL_VAR( OC_TTD | OC_UINT16, 1, &_old_produced[0].waiting ),
  OCL_VAR( OC_TTD | OC_UINT16, 1, &_old_produced[1].waiting ),
  OCL_VAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, 1, &_old_produced[0].waiting ),
  OCL_VAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, 1, &_old_produced[1].waiting ),
 
  OCL_VAR(  OC_UINT8, 1, &_old_produced[0].rate ),
  OCL_VAR(  OC_UINT8, 1, &_old_produced[1].rate ),
 
  OCL_NULL( 3 ),  
 
  OCL_SVAR(  OC_UINT8, Industry, prod_level ),
 
  OCL_VAR( OC_UINT16, 1, &_old_produced[0].history[THIS_MONTH].production ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[1].history[THIS_MONTH].production ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[0].history[THIS_MONTH].transported ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[1].history[THIS_MONTH].transported ),
 
  OCL_NULL( 2 ), 
 
  OCL_VAR( OC_UINT16, 1, &_old_produced[0].history[LAST_MONTH].production ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[1].history[LAST_MONTH].production ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[0].history[LAST_MONTH].transported ),
  OCL_VAR( OC_UINT16, 1, &_old_produced[1].history[LAST_MONTH].transported ),
 
  OCL_SVAR(  OC_UINT8, Industry, type ),
  OCL_SVAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, Industry, counter ),
  OCL_SVAR(  OC_UINT8, Industry, owner ),
  OCL_SVAR(  OC_UINT8, Industry, random_colour ),
  OCL_SVAR( OC_TTD | OC_FILE_U8 | OC_VAR_I32, Industry, last_prod_year ),
  OCL_SVAR( OC_TTD | OC_UINT16, Industry, counter ),
  OCL_SVAR( OC_TTD | OC_UINT8, Industry, was_cargo_delivered ),
 
  OCL_CNULL( OC_TTD, 9 ), 
 
  OCL_END()
};
 
static bool LoadOldIndustry(LoadgameState &ls, int num)
{
  Industry *i = new (IndustryID(num)) Industry();
  if (!LoadChunk(ls, i, industry_chunk)) return false;
 
  if (i->location.tile != 0) {
    /* Copy data from old fixed arrays to industry. */
    std::move(std::begin(_old_accepted), std::end(_old_accepted), std::back_inserter(i->accepted));
    std::copy(std::begin(_old_produced), std::end(_old_produced), std::back_inserter(i->produced));
 
    i->town = RemapTown(i->location.tile);
 
    if (_savegame_type == SGT_TTO) {
      if (i->type > 0x06) i->type++; // Printing Works were added
      if (i->type == 0x0A) i->type = 0x12; // Iron Ore Mine has different ID
 
      TimerGameEconomy::YearMonthDay ymd = TimerGameEconomy::ConvertDateToYMD(TimerGameEconomy::date);
      i->last_prod_year = ymd.year;
 
      i->random_colour = RemapTTOColour(i->random_colour);
    }
 
    Industry::industries[i->type].insert(i->index);
  } else {
    delete i;
  }
 
  return true;
}
 
static CompanyID _current_company_id;
static int32_t _old_yearly;
 
static const OldChunks _company_yearly_chunk[] = {
  OCL_VAR(  OC_INT32,   1, &_old_yearly ),
  OCL_END()
};
 
static bool LoadOldCompanyYearly(LoadgameState &ls, int num)
{
  Company *c = Company::Get(_current_company_id);
 
  for (uint i = 0; i < 13; i++) {
    if (_savegame_type == SGT_TTO && i == 6) {
      _old_yearly = 0; // property maintenance
    } else {
      if (!LoadChunk(ls, nullptr, _company_yearly_chunk)) return false;
    }
 
    c->yearly_expenses[num][i] = _old_yearly;
  }
 
  return true;
}
 
static const OldChunks _company_economy_chunk[] = {
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, CompanyEconomyEntry, income ),
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, CompanyEconomyEntry, expenses ),
  OCL_SVAR( OC_INT32,                 CompanyEconomyEntry, delivered_cargo[NUM_CARGO - 1] ),
  OCL_SVAR( OC_INT32,                 CompanyEconomyEntry, performance_history ),
  OCL_SVAR( OC_TTD | OC_FILE_I32 | OC_VAR_I64, CompanyEconomyEntry, company_value ),
 
  OCL_END()
};
 
static bool LoadOldCompanyEconomy(LoadgameState &ls, int)
{
  Company *c = Company::Get(_current_company_id);
 
  if (!LoadChunk(ls, &c->cur_economy, _company_economy_chunk)) return false;
 
  /* Don't ask, but the number in TTD(Patch) are inversed to OpenTTD */
  c->cur_economy.income   = -c->cur_economy.income;
  c->cur_economy.expenses = -c->cur_economy.expenses;
 
  for (uint i = 0; i < 24; i++) {
    if (!LoadChunk(ls, &c->old_economy[i], _company_economy_chunk)) return false;
 
    c->old_economy[i].income   = -c->old_economy[i].income;
    c->old_economy[i].expenses = -c->old_economy[i].expenses;
  }
 
  return true;
}
 
static const OldChunks _company_chunk[] = {
  OCL_VAR ( OC_UINT16,   1, &_old_string_id ),
  OCL_SVAR( OC_UINT32, Company, name_2 ),
  OCL_SVAR( OC_UINT32, Company, face.bits ),
  OCL_VAR ( OC_UINT16,   1, &_old_string_id_2 ),
  OCL_SVAR( OC_UINT32, Company, president_name_2 ),
 
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, Company, money ),
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, Company, current_loan ),
 
  OCL_SVAR(  OC_UINT8, Company, colour ),
  OCL_SVAR(  OC_UINT8, Company, money_fraction ),
  OCL_SVAR(  OC_UINT8, Company, months_of_bankruptcy ),
  OCL_SVAR( OC_FILE_U8  | OC_VAR_U16, Company, bankrupt_asked ),
  OCL_SVAR( OC_FILE_U32 | OC_VAR_I64, Company, bankrupt_value ),
  OCL_SVAR( OC_UINT16, Company, bankrupt_timeout ),
 
  OCL_CNULL( OC_TTD, 4 ), // cargo_types
  OCL_CNULL( OC_TTO, 2 ), // cargo_types
 
  OCL_CHUNK( 3, LoadOldCompanyYearly ),
  OCL_CHUNK( 1, LoadOldCompanyEconomy ),
 
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I32, Company, inaugurated_year),
  OCL_SVAR(                  OC_TILE, Company, last_build_coordinate ),
  OCL_SVAR(                 OC_UINT8, Company, num_valid_stat_ent ),
 
  OCL_NULL( 230 ),         // Old AI
 
  OCL_SVAR(  OC_UINT8, Company, block_preview ),
  OCL_CNULL( OC_TTD, 1 ),           // Old AI
  OCL_CNULL( OC_TTD, 1 ), // avail_railtypes
  OCL_SVAR(   OC_TILE, Company, location_of_HQ ),
 
  OCL_CNULL( OC_TTD, 4 ), // Shares
 
  OCL_CNULL( OC_TTD, 8 ), // junk at end of chunk
 
  OCL_END()
};
 
static bool LoadOldCompany(LoadgameState &ls, int num)
{
  Company *c = new (CompanyID(num)) Company();
 
  _current_company_id = (CompanyID)num;
 
  if (!LoadChunk(ls, c, _company_chunk)) return false;
 
  if (_old_string_id == 0) {
    delete c;
    return true;
  }
 
  if (_savegame_type == SGT_TTO) {
    /* adjust manager's face */
    if (HasBit(c->face.bits, 27) && GB(c->face.bits, 26, 1) == GB(c->face.bits, 19, 1)) {
      /* if face would be black in TTD, adjust tie colour and thereby face colour */
      ClrBit(c->face.bits, 27);
    }
 
    /* Company name */
    if (_old_string_id == 0 || _old_string_id == 0x4C00) {
      _old_string_id = STR_SV_UNNAMED; // "Unnamed"
    } else if (GB(_old_string_id, 8, 8) == 0x52) {
      _old_string_id += 0x2A00; // Custom name
    } else {
      _old_string_id = RemapOldStringID(_old_string_id += 0x240D); // Automatic name
    }
    c->name_1 = _old_string_id;
 
    /* Manager name */
    switch (_old_string_id_2) {
      case 0x4CDA: _old_string_id_2 = SPECSTR_PRESIDENT_NAME;    break; // automatic name
      case 0x0006: _old_string_id_2 = STR_SV_EMPTY;              break; // empty name
      default:     _old_string_id_2 = _old_string_id_2 + 0x2A00; break; // custom name
    }
    c->president_name_1 = _old_string_id_2;
 
    c->colour = RemapTTOColour(c->colour);
 
    if (num != 0) c->is_ai = true;
  } else {
    c->name_1 = RemapOldStringID(_old_string_id);
    c->president_name_1 = RemapOldStringID(_old_string_id_2);
 
    if (num == 0) {
      /* If the first company has no name, make sure we call it UNNAMED */
      if (c->name_1 == STR_NULL) {
        c->name_1 = STR_SV_UNNAMED;
      }
    } else {
      /* Beside some multiplayer maps (1 on 1), which we don't official support,
       * all other companies are an AI.. mark them as such */
      c->is_ai = true;
    }
 
    /* Sometimes it is better to not ask.. in old scenarios, the money
     * was always 893288 pounds. In the newer versions this is correct,
     * but correct for those oldies
     * Ps: this also means that if you had exact 893288 pounds, you will go back
     * to 100000.. this is a very VERY small chance ;) */
    if (c->money == 893288) c->money = c->current_loan = 100000;
  }
 
  _company_colours[num] = c->colour;
  c->inaugurated_year -= EconomyTime::ORIGINAL_BASE_YEAR;
 
  return true;
}
 
static uint32_t _old_order_ptr;
static uint16_t _old_next_ptr;
static typename VehicleID::BaseType _current_vehicle_id;
 
static const OldChunks vehicle_train_chunk[] = {
  OCL_SVAR(  OC_UINT8, Train, track ),
  OCL_SVAR(  OC_UINT8, Train, force_proceed ),
  OCL_SVAR( OC_UINT16, Train, crash_anim_pos ),
  OCL_SVAR(  OC_UINT8, Train, railtype ),
 
  OCL_NULL( 5 ), 
 
  OCL_END()
};
 
static const OldChunks vehicle_road_chunk[] = {
  OCL_SVAR(  OC_UINT8, RoadVehicle, state ),
  OCL_SVAR(  OC_UINT8, RoadVehicle, frame ),
  OCL_SVAR( OC_UINT16, RoadVehicle, blocked_ctr ),
  OCL_SVAR(  OC_UINT8, RoadVehicle, overtaking ),
  OCL_SVAR(  OC_UINT8, RoadVehicle, overtaking_ctr ),
  OCL_SVAR( OC_UINT16, RoadVehicle, crashed_ctr ),
  OCL_SVAR(  OC_UINT8, RoadVehicle, reverse_ctr ),
 
  OCL_NULL( 1 ), 
 
  OCL_END()
};
 
static const OldChunks vehicle_ship_chunk[] = {
  OCL_SVAR(  OC_UINT8, Ship, state ),
 
  OCL_NULL( 9 ), 
 
  OCL_END()
};
 
static const OldChunks vehicle_air_chunk[] = {
  OCL_SVAR(  OC_UINT8, Aircraft, pos ),
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Aircraft, targetairport ),
  OCL_SVAR( OC_UINT16, Aircraft, crashed_counter ),
  OCL_SVAR(  OC_UINT8, Aircraft, state ),
 
  OCL_NULL( 5 ), 
 
  OCL_END()
};
 
static const OldChunks vehicle_effect_chunk[] = {
  OCL_SVAR( OC_UINT16, EffectVehicle, animation_state ),
  OCL_SVAR(  OC_UINT8, EffectVehicle, animation_substate ),
 
  OCL_NULL( 7 ), // Junk
 
  OCL_END()
};
 
static const OldChunks vehicle_disaster_chunk[] = {
  OCL_SVAR( OC_UINT16, DisasterVehicle, image_override ),
  OCL_SVAR( OC_UINT16, DisasterVehicle, big_ufo_destroyer_target ),
 
  OCL_NULL( 6 ), 
 
  OCL_END()
};
 
static const OldChunks vehicle_empty_chunk[] = {
  OCL_NULL( 10 ), 
 
  OCL_END()
};
 
static bool LoadOldVehicleUnion(LoadgameState &ls, int)
{
  Vehicle *v = Vehicle::GetIfValid(_current_vehicle_id);
  uint temp = ls.total_read;
  bool res;
 
  if (v == nullptr) {
    res = LoadChunk(ls, nullptr, vehicle_empty_chunk);
  } else {
    switch (v->type) {
      default: SlErrorCorrupt("Invalid vehicle type");
      case VEH_TRAIN   : res = LoadChunk(ls, v, vehicle_train_chunk);    break;
      case VEH_ROAD    : res = LoadChunk(ls, v, vehicle_road_chunk);     break;
      case VEH_SHIP    : res = LoadChunk(ls, v, vehicle_ship_chunk);     break;
      case VEH_AIRCRAFT: res = LoadChunk(ls, v, vehicle_air_chunk);      break;
      case VEH_EFFECT  : res = LoadChunk(ls, v, vehicle_effect_chunk);   break;
      case VEH_DISASTER: res = LoadChunk(ls, v, vehicle_disaster_chunk); break;
    }
  }
 
  /* This chunk size should always be 10 bytes */
  if (ls.total_read - temp != 10) {
    Debug(oldloader, 0, "Assert failed in VehicleUnion: invalid chunk size");
    return false;
  }
 
  return res;
}
 
static uint16_t _cargo_count;
 
static const OldChunks vehicle_chunk[] = {
  OCL_SVAR(  OC_UINT8, Vehicle, subtype ),
 
  OCL_NULL( 2 ),         
  OCL_NULL( 2 ),         
 
  OCL_VAR ( OC_UINT32,   1, &_old_order_ptr ),
  OCL_VAR ( OC_UINT16,   1, &_old_order ),
 
  OCL_NULL ( 1 ), 
  OCL_SVAR(  OC_UINT8, Vehicle, cur_implicit_order_index ),
  OCL_SVAR(   OC_TILE, Vehicle, dest_tile ),
  OCL_SVAR( OC_UINT16, Vehicle, load_unload_ticks ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Vehicle, date_of_last_service ),
  OCL_SVAR( OC_UINT16, Vehicle, service_interval ),
  OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Vehicle, last_station_visited ),
  OCL_SVAR( OC_TTD | OC_UINT8, Vehicle, tick_counter ),
  OCL_CNULL( OC_TTD, 2 ), 
  OCL_CNULL( OC_TTO, 1 ), 
 
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I32, Vehicle, x_pos ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I32, Vehicle, y_pos ),
  OCL_SVAR( OC_FILE_U8  | OC_VAR_I32, Vehicle, z_pos ),
  OCL_SVAR(  OC_UINT8, Vehicle, direction ),
  OCL_NULL( 2 ),         
  OCL_NULL( 2 ),         
  OCL_NULL( 1 ),         
 
  OCL_SVAR(  OC_UINT8, Vehicle, owner ),
  OCL_SVAR(   OC_TILE, Vehicle, tile ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Vehicle, sprite_cache.sprite_seq.seq[0].sprite ),
 
  OCL_NULL( 8 ),        
 
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U8, Vehicle, vehstatus ),
  OCL_SVAR( OC_TTD | OC_UINT16, Vehicle, cur_speed ),
  OCL_SVAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, Vehicle, cur_speed ),
  OCL_SVAR(  OC_UINT8, Vehicle, subspeed ),
  OCL_SVAR(  OC_UINT8, Vehicle, acceleration ),
  OCL_SVAR(  OC_UINT8, Vehicle, progress ),
 
  OCL_SVAR(  OC_UINT8, Vehicle, cargo_type ),
  OCL_SVAR( OC_TTD | OC_UINT16, Vehicle, cargo_cap ),
  OCL_SVAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, Vehicle, cargo_cap ),
  OCL_VAR ( OC_TTD | OC_UINT16, 1, &_cargo_count ),
  OCL_VAR ( OC_TTO | OC_FILE_U8 | OC_VAR_U16, 1, &_cargo_count ),
  OCL_VAR (  OC_UINT8, 1,       &_cargo_source ),
  OCL_VAR (  OC_UINT8, 1,       &_cargo_periods ),
 
  OCL_SVAR( OC_TTO | OC_UINT8, Vehicle, tick_counter ),
 
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Vehicle, age ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Vehicle, max_age ),
  OCL_SVAR( OC_FILE_U8 | OC_VAR_I32, Vehicle, build_year ),
  OCL_SVAR( OC_FILE_U8 | OC_VAR_U16, Vehicle, unitnumber ),
 
  OCL_SVAR( OC_TTD | OC_UINT16, Vehicle, engine_type ),
  OCL_SVAR( OC_TTO | OC_FILE_U8 | OC_VAR_U16, Vehicle, engine_type ),
 
  OCL_SVAR(  OC_UINT8, Vehicle, spritenum ),
  OCL_SVAR(  OC_UINT8, Vehicle, day_counter ),
 
  OCL_SVAR(  OC_UINT8, Vehicle, breakdowns_since_last_service ),
  OCL_SVAR(  OC_UINT8, Vehicle, breakdown_ctr ),
  OCL_SVAR(  OC_UINT8, Vehicle, breakdown_delay ),
  OCL_SVAR(  OC_UINT8, Vehicle, breakdown_chance ),
 
  OCL_CNULL( OC_TTO, 1 ),
 
  OCL_SVAR( OC_UINT16, Vehicle, reliability ),
  OCL_SVAR( OC_UINT16, Vehicle, reliability_spd_dec ),
 
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, Vehicle, profit_this_year ),
  OCL_SVAR( OC_FILE_I32 | OC_VAR_I64, Vehicle, profit_last_year ),
 
  OCL_VAR ( OC_UINT16,   1, &_old_next_ptr ),
 
  OCL_SVAR( OC_FILE_U32 | OC_VAR_I64, Vehicle, value ),
 
  OCL_VAR ( OC_UINT16,   1, &_old_string_id ),
 
  OCL_CHUNK( 1, LoadOldVehicleUnion ),
 
  OCL_CNULL( OC_TTO, 24 ), 
  OCL_CNULL( OC_TTD, 20 ), 
 
  OCL_END()
};
 
bool LoadOldVehicle(LoadgameState &ls, int num)
{
  /* Read the TTDPatch flags, because we need some info from it */
  ReadTTDPatchFlags(ls);
 
  for (uint i = 0; i < ls.vehicle_multiplier; i++) {
    _current_vehicle_id = num * ls.vehicle_multiplier + i;
 
    Vehicle *v;
 
    if (_savegame_type == SGT_TTO) {
      uint type = ReadByte(ls);
      switch (type) {
        default: return false;
        case 0x00 /* VEH_INVALID  */: v = nullptr;                                        break;
        case 0x25 /* MONORAIL     */:
        case 0x20 /* VEH_TRAIN    */: v = new (VehicleID(_current_vehicle_id)) Train();           break;
        case 0x21 /* VEH_ROAD     */: v = new (VehicleID(_current_vehicle_id)) RoadVehicle();     break;
        case 0x22 /* VEH_SHIP     */: v = new (VehicleID(_current_vehicle_id)) Ship();            break;
        case 0x23 /* VEH_AIRCRAFT */: v = new (VehicleID(_current_vehicle_id)) Aircraft();        break;
        case 0x24 /* VEH_EFFECT   */: v = new (VehicleID(_current_vehicle_id)) EffectVehicle();   break;
        case 0x26 /* VEH_DISASTER */: v = new (VehicleID(_current_vehicle_id)) DisasterVehicle(); break;
      }
 
      if (!LoadChunk(ls, v, vehicle_chunk)) return false;
      if (v == nullptr) continue;
      v->refit_cap = v->cargo_cap;
 
      SpriteID sprite = v->sprite_cache.sprite_seq.seq[0].sprite;
      /* no need to override other sprites */
      if (IsInsideMM(sprite, 1460, 1465)) {
        sprite += 580; // aircraft smoke puff
      } else if (IsInsideMM(sprite, 2096, 2115)) {
        sprite += 977; // special effects part 1
      } else if (IsInsideMM(sprite, 2396, 2436)) {
        sprite += 1305; // special effects part 2
      } else if (IsInsideMM(sprite, 2516, 2539)) {
        sprite += 1385; // rotor or disaster-related vehicles
      }
      v->sprite_cache.sprite_seq.seq[0].sprite = sprite;
 
      switch (v->type) {
        case VEH_TRAIN: {
          static const uint8_t spriteset_rail[] = {
              0,   2,   4,   4,   8,  10,  12,  14,  16,  18,  20,  22,  40,  42,  44,  46,
             48,  52,  54,  66,  68,  70,  72,  74,  76,  78,  80,  82,  84,  86, 120, 122,
            124, 126, 128, 130, 132, 134, 136, 138, 140
          };
          if (v->spritenum / 2 >= lengthof(spriteset_rail)) return false;
          v->spritenum = spriteset_rail[v->spritenum / 2]; // adjust railway sprite set offset
          /* Should be the original values for monorail / rail, can't use RailType constants */
          Train::From(v)->railtype = static_cast<RailType>(type == 0x25 ? 1 : 0);
          break;
        }
 
        case VEH_ROAD:
          if (v->spritenum >= 22) v->spritenum += 12;
          break;
 
        case VEH_SHIP:
          v->spritenum += 2;
 
          switch (v->spritenum) {
            case 2: // oil tanker && cargo type != oil
              if (v->cargo_type != 3) v->spritenum = 0; // make it a coal/goods ship
              break;
            case 4: // passenger ship && cargo type == mail
              if (v->cargo_type == 2) v->spritenum = 0; // make it a mail ship
              break;
            default:
              break;
          }
          break;
 
        default:
          break;
      }
 
      switch (_old_string_id) {
        case 0x0000: break; // empty (invalid vehicles)
        case 0x0006: _old_string_id  = STR_SV_EMPTY;              break; // empty (special vehicles)
        case 0x8495: _old_string_id  = STR_SV_TRAIN_NAME;         break; // "Train X"
        case 0x8842: _old_string_id  = STR_SV_ROAD_VEHICLE_NAME;  break; // "Road Vehicle X"
        case 0x8C3B: _old_string_id  = STR_SV_SHIP_NAME;          break; // "Ship X"
        case 0x9047: _old_string_id  = STR_SV_AIRCRAFT_NAME;      break; // "Aircraft X"
        default:     _old_string_id += 0x2A00;                    break; // custom name
      }
 
      ls.vehicle_names[_current_vehicle_id] = _old_string_id;
    } else {
      /* Read the vehicle type and allocate the right vehicle */
      switch (ReadByte(ls)) {
        default: SlErrorCorrupt("Invalid vehicle type");
        case 0x00 /* VEH_INVALID */: v = nullptr;                                        break;
        case 0x10 /* VEH_TRAIN   */: v = new (VehicleID(_current_vehicle_id)) Train();           break;
        case 0x11 /* VEH_ROAD    */: v = new (VehicleID(_current_vehicle_id)) RoadVehicle();     break;
        case 0x12 /* VEH_SHIP    */: v = new (VehicleID(_current_vehicle_id)) Ship();            break;
        case 0x13 /* VEH_AIRCRAFT*/: v = new (VehicleID(_current_vehicle_id)) Aircraft();        break;
        case 0x14 /* VEH_EFFECT  */: v = new (VehicleID(_current_vehicle_id)) EffectVehicle();   break;
        case 0x15 /* VEH_DISASTER*/: v = new (VehicleID(_current_vehicle_id)) DisasterVehicle(); break;
      }
 
      if (!LoadChunk(ls, v, vehicle_chunk)) return false;
      if (v == nullptr) continue;
 
      ls.vehicle_names[_current_vehicle_id] = RemapOldStringID(_old_string_id);
 
      /* This should be consistent, else we have a big problem... */
      if (v->index != _current_vehicle_id) {
        Debug(oldloader, 0, "Loading failed - vehicle-array is invalid");
        return false;
      }
    }
 
    if (_old_order_ptr != 0 && _old_order_ptr != 0xFFFFFFFF) {
      uint max = _savegame_type == SGT_TTO ? 3000 : 5000;
      uint old_id = RemapOrderIndex(_old_order_ptr);
      if (old_id < max) v->old_orders = old_id + 1;
    }
    v->current_order.AssignOrder(UnpackOldOrder(_old_order));
 
    if (v->type == VEH_DISASTER) {
      DisasterVehicle::From(v)->state = UnpackOldOrder(_old_order).GetDestination().value;
    }
 
    v->next = (Vehicle *)(size_t)_old_next_ptr;
 
    if (_cargo_count != 0 && CargoPacket::CanAllocateItem()) {
      StationID source =    (_cargo_source == 0xFF) ? StationID::Invalid() : StationID{_cargo_source};
      TileIndex source_xy = (source != StationID::Invalid()) ? Station::Get(source)->xy : (TileIndex)0;
      v->cargo.Append(new CargoPacket(_cargo_count, _cargo_periods, source, source_xy, 0));
    }
  }
 
  return true;
}
bool LoadOldVehicle(LoadgameState &ls, int num) {…};
            tile.m2() = 0; {…}
 
bool LoadOldCustomString(LoadgameState &ls, int index)
{
  /*
   * Data is stored in fixed size "cells"; read these completely.
   * Validation and conversion to UTF-8 are happening at a later stage.
   */
  std::string &str = _old_name_array[index];
  str.resize(_savegame_type == SGT_TTO ? 24 : 32);
  for (auto &c : str) c = ReadByte(ls);
 
  return true;
}
bool LoadOldCustomString(LoadgameState &ls, int index) {…}
 
static const OldChunks sign_chunk[] = {
  OCL_VAR ( OC_UINT16, 1, &_old_string_id ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I32, Sign, x ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I32, Sign, y ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_I8, Sign, z ),
 
  OCL_NULL( 6 ),         
 
  OCL_END()
};
 
static bool LoadOldSign(LoadgameState &ls, int num)
{
  Sign *si = new (SignID(num)) Sign();
  if (!LoadChunk(ls, si, sign_chunk)) return false;
 
  if (_old_string_id != 0) {
    if (_savegame_type == SGT_TTO) {
      if (_old_string_id != 0x140A) si->name = CopyFromOldName(_old_string_id + 0x2A00);
    } else {
      si->name = CopyFromOldName(RemapOldStringID(_old_string_id));
    }
    si->owner = OWNER_NONE;
  } else {
    delete si;
  }
 
  return true;
}
 
static const OldChunks engine_chunk[] = {
  OCL_SVAR( OC_UINT16, Engine, company_avail ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Engine, intro_date ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, Engine, age ),
  OCL_SVAR( OC_UINT16, Engine, reliability ),
  OCL_SVAR( OC_UINT16, Engine, reliability_spd_dec ),
  OCL_SVAR( OC_UINT16, Engine, reliability_start ),
  OCL_SVAR( OC_UINT16, Engine, reliability_max ),
  OCL_SVAR( OC_UINT16, Engine, reliability_final ),
  OCL_SVAR( OC_UINT16, Engine, duration_phase_1 ),
  OCL_SVAR( OC_UINT16, Engine, duration_phase_2 ),
  OCL_SVAR( OC_UINT16, Engine, duration_phase_3 ),
 
  OCL_NULL( 1 ), // lifelength
  OCL_SVAR(  OC_UINT8, Engine, flags ),
  OCL_NULL( 1 ), // preview_company_rank
  OCL_SVAR(  OC_UINT8, Engine, preview_wait ),
 
  OCL_CNULL( OC_TTD, 2 ), 
 
  OCL_END()
};
 
static bool LoadOldEngine(LoadgameState &ls, int num)
{
  Engine *e = _savegame_type == SGT_TTO ? &_old_engines[num] : GetTempDataEngine(static_cast<EngineID>(num));
  return LoadChunk(ls, e, engine_chunk);
}
 
static bool LoadOldEngineName(LoadgameState &ls, int num)
{
  Engine *e = GetTempDataEngine(static_cast<EngineID>(num));
  e->name = CopyFromOldName(RemapOldStringID(ReadUint16(ls)));
  return true;
}
 
static const OldChunks subsidy_chunk[] = {
  OCL_SVAR(  OC_UINT8, Subsidy, cargo_type ),
  OCL_SVAR(  OC_UINT8, Subsidy, remaining ),
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Subsidy, src ),
  OCL_SVAR(  OC_FILE_U8 | OC_VAR_U16, Subsidy, dst ),
 
  OCL_END()
};
 
static bool LoadOldSubsidy(LoadgameState &ls, int num)
{
  Subsidy *s = new (SubsidyID(num)) Subsidy();
  bool ret = LoadChunk(ls, s, subsidy_chunk);
  if (!IsValidCargoType(s->cargo_type)) delete s;
  return ret;
}
 
static const OldChunks game_difficulty_chunk[] = {
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, max_no_competitors ),
  OCL_NULL( 2), // competitor_start_time
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, number_towns ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, industry_density ),
  OCL_SVAR( OC_FILE_U16 | OC_VAR_U32, DifficultySettings, max_loan ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, initial_interest ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, vehicle_costs ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, competitor_speed ),
  OCL_NULL( 2), // competitor_intelligence
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, vehicle_breakdowns ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, subsidy_multiplier ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, construction_cost ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, terrain_type ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, quantity_sea_lakes ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, economy ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, line_reverse_mode ),
  OCL_SVAR( OC_FILE_U16 |  OC_VAR_U8, DifficultySettings, disasters ),
  OCL_END()
};
 
static bool LoadOldGameDifficulty(LoadgameState &ls, int)
{
  bool ret = LoadChunk(ls, &_settings_game.difficulty, game_difficulty_chunk);
  _settings_game.difficulty.max_loan *= 1000;
  return ret;
}
 
 
static bool LoadOldMapPart1(LoadgameState &ls, int)
{
  if (_savegame_type == SGT_TTO) {
    Map::Allocate(OLD_MAP_SIZE, OLD_MAP_SIZE);
  }
 
  for (auto t : Map::Iterate()) {
    t.m1() = ReadByte(ls);
  }
  for (auto t : Map::Iterate()) {
    t.m2() = ReadByte(ls);
  }
 
  if (_savegame_type != SGT_TTO) {
    /* old map3 is split into to m3 and m4 */
    for (auto t : Map::Iterate()) {
      t.m3() = ReadByte(ls);
      t.m4() = ReadByte(ls);
    }
    auto range = Map::Iterate();
    for (auto it = range.begin(); it != range.end(); /* nothing. */) {
      uint8_t b = ReadByte(ls);
      for (int i = 0; i < 8; i += 2, ++it) (*it).m6() = GB(b, i, 2);
    }
  }
 
  return true;
}
 
static bool LoadOldMapPart2(LoadgameState &ls, int)
{
  for (auto t : Map::Iterate()) {
    t.type() = ReadByte(ls);
  }
  for (auto t : Map::Iterate()) {
    t.m5() = ReadByte(ls);
  }
 
  return true;
}
 
static bool LoadTTDPatchExtraChunks(LoadgameState &ls, int)
{
  ReadTTDPatchFlags(ls);
 
  Debug(oldloader, 2, "Found {} extra chunk(s)", _old_extra_chunk_nums);
 
  for (int i = 0; i != _old_extra_chunk_nums; i++) {
    uint16_t id = ReadUint16(ls);
    uint32_t len = ReadUint32(ls);
 
    switch (id) {
      /* List of GRFIDs, used in the savegame. 0x8004 is the new ID
       * They are saved in a 'GRFID:4 active:1' format, 5 bytes for each entry */
      case 0x2:
      case 0x8004: {
        /* Skip the first element: TTDP hack for the Action D special variables (FFFF0000 01) */
        ReadUint32(ls); ReadByte(ls); len -= 5;
 
        ClearGRFConfigList(_grfconfig);
        while (len != 0) {
          uint32_t grfid = ReadUint32(ls);
 
          if (ReadByte(ls) == 1) {
            auto c = std::make_unique<GRFConfig>("TTDP game, no information");
            c->ident.grfid = grfid;
 
            Debug(oldloader, 3, "TTDPatch game using GRF file with GRFID {:08X}", std::byteswap(c->ident.grfid));
            AppendToGRFConfigList(_grfconfig, std::move(c));
          }
          len -= 5;
        }
 
        /* Append static NewGRF configuration */
        AppendStaticGRFConfigs(_grfconfig);
        break;
      }
 
      /* TTDPatch version and configuration */
      case 0x3:
        _ttdp_version = ReadUint32(ls);
        Debug(oldloader, 3, "Game saved with TTDPatch version {}.{}.{} r{}",
          GB(_ttdp_version, 24, 8), GB(_ttdp_version, 20, 4), GB(_ttdp_version, 16, 4), GB(_ttdp_version, 0, 16));
        len -= 4;
        while (len-- != 0) ReadByte(ls); // skip the configuration
        break;
 
      default:
        Debug(oldloader, 4, "Skipping unknown extra chunk {}", id);
        while (len-- != 0) ReadByte(ls);
        break;
    }
  }
 
  return true;
}
 
extern TileIndex _cur_tileloop_tile;
extern uint16_t _disaster_delay;
extern uint8_t _trees_tick_ctr;
extern uint8_t _age_cargo_skip_counter; // From misc_sl.cpp
extern uint8_t _old_diff_level;
extern uint8_t _old_units;
static const OldChunks main_chunk[] = {
  OCL_ASSERT( OC_TTD, 0 ),
  OCL_ASSERT( OC_TTO, 0 ),
  OCL_VAR ( OC_FILE_U16 | OC_VAR_U32, 1, &TimerGameCalendar::date ),
  OCL_VAR ( OC_UINT16,   1, &TimerGameCalendar::date_fract ),
  OCL_NULL( 600 ),            
  OCL_VAR ( OC_UINT32,   2, &_random.state ),
 
  OCL_ASSERT( OC_TTD, 0x264 ),
  OCL_ASSERT( OC_TTO, 0x264 ),
 
  OCL_CCHUNK( OC_TTD, 70, LoadOldTown ),
  OCL_CCHUNK( OC_TTO, 80, LoadOldTown ),
 
  OCL_ASSERT( OC_TTD, 0x1C18 ),
  OCL_ASSERT( OC_TTO, 0x1AC4 ),
 
  OCL_CCHUNK( OC_TTD, 5000, LoadOldOrder ),
  OCL_CCHUNK( OC_TTO, 3000, LoadOldOrder ),
 
  OCL_ASSERT( OC_TTD, 0x4328 ),
  OCL_ASSERT( OC_TTO, 0x3234 ),
 
  OCL_CHUNK( 1, LoadOldAnimTileList ),
  OCL_NULL( 4 ),              
 
  OCL_ASSERT( OC_TTO, 0x3438 ),
 
  OCL_CCHUNK( OC_TTD, 255, LoadOldDepot ),
  OCL_CCHUNK( OC_TTO, 252, LoadOldDepot ),
 
  OCL_ASSERT( OC_TTD, 0x4B26 ),
  OCL_ASSERT( OC_TTO, 0x3A20 ),
 
  OCL_NULL( 4 ),              
  OCL_NULL( 2 ),              
  OCL_NULL( 2 ),              
 
  OCL_VAR ( OC_FILE_U16 | OC_VAR_U8, 1, &_age_cargo_skip_counter ),
  OCL_VAR ( OC_FILE_U16 | OC_VAR_U64, 1, &TimerGameTick::counter ),
  OCL_VAR (   OC_TILE,   1, &_cur_tileloop_tile ),
 
  OCL_ASSERT( OC_TTO, 0x3A2E ),
 
  OCL_CNULL( OC_TTO, 48 * 6 ), 
  OCL_CNULL( OC_TTD, 49 * 6 ), 
 
  OCL_ASSERT( OC_TTO, 0x3B4E ),
 
  OCL_CNULL( OC_TTO, 11 * 8 ), 
  OCL_CNULL( OC_TTD, 12 * 8 ), 
 
  OCL_ASSERT( OC_TTD, 0x4CBA ),
  OCL_ASSERT( OC_TTO, 0x3BA6 ),
 
  OCL_CHUNK( 1, LoadOldMapPart1 ),
 
  OCL_ASSERT( OC_TTD, 0x48CBA ),
  OCL_ASSERT( OC_TTO, 0x23BA6 ),
 
  OCL_CCHUNK( OC_TTD, 250, LoadOldStation ),
  OCL_CCHUNK( OC_TTO, 200, LoadOldStation ),
 
  OCL_ASSERT( OC_TTO, 0x29E16 ),
 
  OCL_CCHUNK( OC_TTD, 90, LoadOldIndustry ),
  OCL_CCHUNK( OC_TTO, 100, LoadOldIndustry ),
 
  OCL_ASSERT( OC_TTO, 0x2ADB6 ),
 
  OCL_CHUNK(  8, LoadOldCompany ),
 
  OCL_ASSERT( OC_TTD, 0x547F2 ),
  OCL_ASSERT( OC_TTO, 0x2C746 ),
 
  OCL_CCHUNK( OC_TTD, 850, LoadOldVehicle ),
  OCL_CCHUNK( OC_TTO, 800, LoadOldVehicle ),
 
  OCL_ASSERT( OC_TTD, 0x6F0F2 ),
  OCL_ASSERT( OC_TTO, 0x45746 ),
 
  OCL_CCHUNK( OC_TTD, 500, LoadOldCustomString ),
  OCL_CCHUNK( OC_TTO, 200, LoadOldCustomString ),
 
  OCL_ASSERT( OC_TTO, 0x46A06 ),
 
  OCL_NULL( 0x2000 ),            
 
  OCL_CHUNK( 40, LoadOldSign ),
 
  OCL_ASSERT( OC_TTO, 0x48C36 ),
 
  OCL_CCHUNK( OC_TTD, 256, LoadOldEngine ),
  OCL_CCHUNK( OC_TTO, 103, LoadOldEngine ),
 
  OCL_ASSERT( OC_TTO, 0x496AC ),
 
  OCL_NULL ( 2 ), // _vehicle_id_ctr_day
 
  OCL_CHUNK(  8, LoadOldSubsidy ),
 
  OCL_ASSERT( OC_TTO, 0x496CE ),
 
  OCL_VAR ( OC_FILE_U16 | OC_VAR_U32,   1, &_new_competitor_timeout.period.value ),
 
  OCL_CNULL( OC_TTO, 2 ),  
 
  OCL_VAR ( OC_FILE_I16 | OC_VAR_I32,   1, &_saved_scrollpos_x ),
  OCL_VAR ( OC_FILE_I16 | OC_VAR_I32,   1, &_saved_scrollpos_y ),
  OCL_VAR ( OC_FILE_U16 | OC_VAR_U8,    1, &_saved_scrollpos_zoom ),
 
  OCL_NULL( 4 ),           
  OCL_VAR ( OC_FILE_U32 | OC_VAR_I64,   1, &_economy.old_max_loan_unround ),
  OCL_VAR (  OC_INT16,    1, &_economy.fluct ),
 
  OCL_VAR ( OC_UINT16,    1, &_disaster_delay ),
 
  OCL_ASSERT( OC_TTO, 0x496E4 ),
 
  OCL_CNULL( OC_TTD, 144 ),             
 
  OCL_CCHUNK( OC_TTD, 256, LoadOldEngineName ),
 
  OCL_CNULL( OC_TTD, 144 ),             
  OCL_NULL( 2 ),               
  OCL_NULL( 1 ),               
 
  OCL_VAR (  OC_UINT8,    1, &_settings_game.locale.currency ),
  OCL_VAR (  OC_UINT8,    1, &_old_units ),
  OCL_VAR ( OC_FILE_U8 | OC_VAR_U32,    1, &_cur_company_tick_index ),
 
  OCL_NULL( 2 ),               
  OCL_NULL( 8 ),               
 
  OCL_VAR (  OC_UINT8,    1, &_economy.infl_amount ),
  OCL_VAR (  OC_UINT8,    1, &_economy.infl_amount_pr ),
  OCL_VAR (  OC_UINT8,    1, &_economy.interest_rate ),
  OCL_NULL( 1 ), // available airports
  OCL_VAR (  OC_UINT8,    1, &_settings_game.vehicle.road_side ),
  OCL_VAR (  OC_UINT8,    1, &_settings_game.game_creation.town_name ),
 
  OCL_CHUNK( 1, LoadOldGameDifficulty ),
 
  OCL_ASSERT( OC_TTD, 0x77130 ),
 
  OCL_VAR (  OC_UINT8,    1, &_old_diff_level ),
 
  OCL_VAR ( OC_TTD | OC_UINT8,    1, &_settings_game.game_creation.landscape ),
  OCL_VAR ( OC_TTD | OC_UINT8,    1, &_trees_tick_ctr ),
 
  OCL_CNULL( OC_TTD, 1 ),               
  OCL_VAR ( OC_TTD | OC_UINT8,    1, &_settings_game.game_creation.snow_line_height ),
 
  OCL_CNULL( OC_TTD, 32 ),              
  OCL_CNULL( OC_TTD, 36 ),              
 
  OCL_ASSERT( OC_TTD, 0x77179 ),
  OCL_ASSERT( OC_TTO, 0x4971D ),
 
  OCL_CHUNK( 1, LoadOldMapPart2 ),
 
  OCL_ASSERT( OC_TTD, 0x97179 ),
  OCL_ASSERT( OC_TTO, 0x6971D ),
 
  /* Below any (if available) extra chunks from TTDPatch can follow */
  OCL_CHUNK(1, LoadTTDPatchExtraChunks),
 
  OCL_END()
};
 
bool LoadTTDMain(LoadgameState &ls)
{
  Debug(oldloader, 3, "Reading main chunk...");
 
  _read_ttdpatch_flags = false;
 
  /* Load the biggest chunk */
  if (!LoadChunk(ls, nullptr, main_chunk)) {
    Debug(oldloader, 0, "Loading failed");
    return false;
  }
 
  Debug(oldloader, 3, "Done, converting game data...");
 
  FixTTDMapArray();
  FixTTDDepots();
 
  /* Fix some general stuff */
  if (to_underlying(_settings_game.game_creation.landscape) >= NUM_LANDSCAPE) _settings_game.game_creation.landscape = LandscapeType::Temperate;
 
  /* Fix the game to be compatible with OpenTTD */
  FixOldTowns();
  FixOldVehicles(ls);
 
  /* We have a new difficulty setting */
  _settings_game.difficulty.town_council_tolerance = Clamp(_old_diff_level, 0, 2);
 
  Debug(oldloader, 3, "Finished converting game data");
  Debug(oldloader, 1, "TTD(Patch) savegame successfully converted");
 
  return true;
}
 
bool LoadTTOMain(LoadgameState &ls)
{
  Debug(oldloader, 3, "Reading main chunk...");
 
  _read_ttdpatch_flags = false;
 
  std::array<uint8_t, 103 * sizeof(Engine)> engines; // we don't want to call Engine constructor here
  _old_engines = (Engine *)engines.data();
 
  /* Load the biggest chunk */
  if (!LoadChunk(ls, nullptr, main_chunk)) {
    Debug(oldloader, 0, "Loading failed");
    return false;
  }
  Debug(oldloader, 3, "Done, converting game data...");
 
  if (_settings_game.game_creation.town_name != 0) _settings_game.game_creation.town_name++;
 
  _settings_game.game_creation.landscape = LandscapeType::Temperate;
  _trees_tick_ctr = 0xFF;
 
  if (!FixTTOMapArray() || !FixTTOEngines()) {
    Debug(oldloader, 0, "Conversion failed");
    return false;
  }
 
  FixOldTowns();
  FixOldVehicles(ls);
  FixTTOCompanies();
 
  /* We have a new difficulty setting */
  _settings_game.difficulty.town_council_tolerance = Clamp(_old_diff_level, 0, 2);
 
  /* SVXConverter about cargo payment rates correction:
   * "increase them to compensate for the faster time advance in TTD compared to TTO
   * which otherwise would cause much less income while the annual running costs of
   * the vehicles stay the same" */
  _economy.inflation_payment = std::min(_economy.inflation_payment * 124 / 74, MAX_INFLATION);
 
  Debug(oldloader, 3, "Finished converting game data");
  Debug(oldloader, 1, "TTO savegame successfully converted");
 
  return true;
}
            break; {…}