OpenTTD/vehicle.c

/* $Id$ */

#include "stdafx.h"
#include "openttd.h"
#include "spritecache.h"
#include "table/sprites.h"
#include "table/strings.h"
#include "functions.h"
#include "map.h"
#include "tile.h"
#include "vehicle.h"
#include "gfx.h"
#include "viewport.h"
#include "news.h"
#include "command.h"
#include "saveload.h"
#include "player.h"
#include "engine.h"
#include "sound.h"
#include "debug.h"
#include "vehicle_gui.h"
#include "depot.h"
#include "station.h"
#include "gui.h"
#include "rail.h"

#define INVALID_COORD (-0x8000)
#define GEN_HASH(x,y) (((x & 0x1F80)>>7) + ((y & 0xFC0)))

/*
 *	These command macros are used to call vehicle type specific commands with non type specific commands
 *	it should be used like: DoCommandP(x, y, p1, p2, flags, CMD_STARTSTOP_VEH(v->type))
 *	that line will start/stop a vehicle nomatter what type it is
 *	VEH_Train is used as an offset because the vehicle type values doesn't start with 0
 */

#define CMD_BUILD_VEH(x)		   _veh_build_proc_table[ x - VEH_Train]
#define CMD_SELL_VEH(x)				_veh_sell_proc_table[ x - VEH_Train]
#define CMD_STARTSTOP_VEH(x)  _veh_start_stop_proc_table[ x - VEH_Train]
#define CMD_REFIT_VEH(x)		   _veh_refit_proc_table[ x - VEH_Train]

static uint32 const _veh_build_proc_table[] = {
	CMD_BUILD_RAIL_VEHICLE,
	CMD_BUILD_ROAD_VEH,
	CMD_BUILD_SHIP,
	CMD_BUILD_AIRCRAFT,
};
static uint32 const _veh_sell_proc_table[] = {
	CMD_SELL_RAIL_WAGON,
	CMD_SELL_ROAD_VEH,
	CMD_SELL_SHIP,
	CMD_SELL_AIRCRAFT,
};
static uint32 const _veh_start_stop_proc_table[] = {
	CMD_START_STOP_TRAIN,
	CMD_START_STOP_ROADVEH,
	CMD_START_STOP_SHIP,
	CMD_START_STOP_AIRCRAFT,
};
static uint32 const _veh_refit_proc_table[] = {
	CMD_REFIT_RAIL_VEHICLE,
	0,	// road vehicles can't be refitted
	CMD_REFIT_SHIP,
	CMD_REFIT_AIRCRAFT,
};


enum {
	/* Max vehicles: 64000 (512 * 125) */
	VEHICLES_POOL_BLOCK_SIZE_BITS = 9,       /* In bits, so (1 << 9) == 512 */
	VEHICLES_POOL_MAX_BLOCKS      = 125,

	BLOCKS_FOR_SPECIAL_VEHICLES   = 2, //! Blocks needed for special vehicles
};

/**
 * Called if a new block is added to the vehicle-pool
 */
static void VehiclePoolNewBlock(uint start_item)
{
	Vehicle *v;

	FOR_ALL_VEHICLES_FROM(v, start_item)
		v->index = start_item++;
}

/* Initialize the vehicle-pool */
MemoryPool _vehicle_pool = { "Vehicle", VEHICLES_POOL_MAX_BLOCKS, VEHICLES_POOL_BLOCK_SIZE_BITS, sizeof(Vehicle), &VehiclePoolNewBlock, 0, 0, NULL };

void VehicleServiceInDepot(Vehicle *v)
{
	v->date_of_last_service = _date;
	v->breakdowns_since_last_service = 0;
	v->reliability = GetEngine(v->engine_type)->reliability;
}

bool VehicleNeedsService(const Vehicle *v)
{
	if (_patches.no_servicing_if_no_breakdowns && _opt.diff.vehicle_breakdowns == 0)
		return false;

	if (v->vehstatus & VS_CRASHED)
		return false; /* Crashed vehicles don't need service anymore */

	return _patches.servint_ispercent ?
		(v->reliability < GetEngine(v->engine_type)->reliability * (100 - v->service_interval) / 100) :
		(v->date_of_last_service + v->service_interval < _date);
}

void VehicleInTheWayErrMsg(Vehicle *v)
{
	StringID id;

	(id = STR_8803_TRAIN_IN_THE_WAY,v->type == VEH_Train) ||
	(id = STR_9000_ROAD_VEHICLE_IN_THE_WAY,v->type == VEH_Road) ||
	(id = STR_A015_AIRCRAFT_IN_THE_WAY,v->type == VEH_Aircraft) ||
		(id = STR_980E_SHIP_IN_THE_WAY, true);

	_error_message = id;
}

static void *EnsureNoVehicleProc(Vehicle *v, void *data)
{
	if (v->tile != *(const TileIndex*)data || v->type == VEH_Disaster)
		return NULL;

	VehicleInTheWayErrMsg(v);
	return v;
}

bool EnsureNoVehicle(TileIndex tile)
{
	return VehicleFromPos(tile, &tile, EnsureNoVehicleProc) == NULL;
}

static void *EnsureNoVehicleProcZ(Vehicle *v, void *data)
{
	const TileInfo *ti = data;

	if (v->tile != ti->tile || v->z_pos != ti->z || v->type == VEH_Disaster)
		return NULL;

	VehicleInTheWayErrMsg(v);
	return v;
}

static inline uint Correct_Z(uint tileh)
{
	// needs z correction for slope-type graphics that have the NORTHERN tile lowered
	// 1, 2, 3, 4, 5, 6 and 7
	return CorrectZ(tileh) ? 8 : 0;
}

uint GetCorrectTileHeight(TileIndex tile)
{
	return Correct_Z(GetTileSlope(tile, NULL));
}

bool EnsureNoVehicleZ(TileIndex tile, byte z)
{
	TileInfo ti;

	FindLandscapeHeightByTile(&ti, tile);
	ti.z = z + Correct_Z(ti.tileh);

	return VehicleFromPos(tile, &ti, EnsureNoVehicleProcZ) == NULL;
}

Vehicle *FindVehicleOnTileZ(TileIndex tile, byte z)
{
	TileInfo ti;

	ti.tile = tile;
	ti.z = z;

	return VehicleFromPos(tile, &ti, EnsureNoVehicleProcZ);
}

Vehicle *FindVehicleBetween(TileIndex from, TileIndex to, byte z)
{
	int x1 = TileX(from);
	int y1 = TileY(from);
	int x2 = TileX(to);
	int y2 = TileY(to);
	Vehicle *veh;

	/* Make sure x1 < x2 or y1 < y2 */
	if (x1 > x2 || y1 > y2) {
		intswap(x1,x2);
		intswap(y1,y2);
	}
	FOR_ALL_VEHICLES(veh) {
		if ((veh->type == VEH_Train || veh->type == VEH_Road) && (z==0xFF || veh->z_pos == z)) {
			if ((veh->x_pos>>4) >= x1 && (veh->x_pos>>4) <= x2 &&
					(veh->y_pos>>4) >= y1 && (veh->y_pos>>4) <= y2) {
				return veh;
			}
		}
	}
	return NULL;
}

void VehiclePositionChanged(Vehicle *v)
{
	int img = v->cur_image;
	Point pt = RemapCoords(v->x_pos + v->x_offs, v->y_pos + v->y_offs, v->z_pos);
	const Sprite* spr = GetSprite(img);

	pt.x += spr->x_offs;
	pt.y += spr->y_offs;

	UpdateVehiclePosHash(v, pt.x, pt.y);

	v->left_coord = pt.x;
	v->top_coord = pt.y;
	v->right_coord = pt.x + spr->width + 2;
	v->bottom_coord = pt.y + spr->height + 2;
}

// Called after load to update coordinates
void AfterLoadVehicles(void)
{
	Vehicle *v;

	FOR_ALL_VEHICLES(v) {
		v->first = NULL;
		if (v->type != 0) {
			switch (v->type) {
				case VEH_Train: v->cur_image = GetTrainImage(v, v->direction); break;
				case VEH_Road: v->cur_image = GetRoadVehImage(v, v->direction); break;
				case VEH_Ship: v->cur_image = GetShipImage(v, v->direction); break;
				case VEH_Aircraft:
					if (v->subtype == 0 || v->subtype == 2) {
						v->cur_image = GetAircraftImage(v, v->direction);
						if (v->next != NULL) {
							v->next->cur_image = v->cur_image;
						}
					}
					break;
				default: break;
			}

			v->left_coord = INVALID_COORD;
			VehiclePositionChanged(v);

			if (v->type == VEH_Train && (v->subtype == TS_Front_Engine || v->subtype == TS_Free_Car))
				TrainConsistChanged(v);
		}
	}
}

static Vehicle *InitializeVehicle(Vehicle *v)
{
	VehicleID index = v->index;
	memset(v, 0, sizeof(Vehicle));
	v->index = index;

	assert(v->orders == NULL);

	v->left_coord = INVALID_COORD;
	v->first = NULL;
	v->next = NULL;
	v->next_hash = INVALID_VEHICLE;
	v->string_id = 0;
	v->next_shared = NULL;
	v->prev_shared = NULL;
	/* random_bits is used to pick out a random sprite for vehicles
	    which are technical the same (newgrf stuff).
	   Because RandomRange() results in desyncs, and because it does
	    not really matter that one client has other visual vehicles than
	    the other, it can be InteractiveRandomRange() without any problem
	*/
	v->random_bits = InteractiveRandomRange(256);
	return v;
}

Vehicle *ForceAllocateSpecialVehicle(void)
{
	/* This stays a strange story.. there should always be room for special
	 * vehicles (special effects all over the map), but with 65k of vehicles
	 * is this realistic to double-check for that? For now we just reserve
	 * BLOCKS_FOR_SPECIAL_VEHICLES times block_size vehicles that may only
	 * be used for special vehicles.. should work nicely :) */

	Vehicle *v;

	FOR_ALL_VEHICLES(v) {
		/* No more room for the special vehicles, return NULL */
		if (v->index >= (1 << _vehicle_pool.block_size_bits) * BLOCKS_FOR_SPECIAL_VEHICLES)
			return NULL;

		if (v->type == 0)
			return InitializeVehicle(v);
	}

	return NULL;
}

Vehicle *AllocateVehicle(void)
{
	/* See note by ForceAllocateSpecialVehicle() why we skip the
	 * first blocks */
	Vehicle *v;

	FOR_ALL_VEHICLES_FROM(v, (1 << _vehicle_pool.block_size_bits) * BLOCKS_FOR_SPECIAL_VEHICLES) {
		if (v->type == 0)
			return InitializeVehicle(v);
	}

	/* Check if we can add a block to the pool */
	if (AddBlockToPool(&_vehicle_pool))
		return AllocateVehicle();

	return NULL;
}

void *VehicleFromPos(TileIndex tile, void *data, VehicleFromPosProc *proc)
{
	int x,y,x2,y2;
	VehicleID veh;
	Point pt = RemapCoords(TileX(tile) * 16, TileY(tile) * 16, 0);

	x2 = ((pt.x + 104) & 0x1F80) >> 7;
	x  = ((pt.x - 174) & 0x1F80) >> 7;

	y2 = ((pt.y + 56) & 0xFC0);
	y  = ((pt.y - 294) & 0xFC0);

	for(;;) {
		int xb = x;
		for(;;) {
			veh = _vehicle_position_hash[ (x+y)&0xFFFF ];
			while (veh != INVALID_VEHICLE) {
				Vehicle *v = GetVehicle(veh);
				void *a;

				if ((a = proc(v, data)) != NULL)
					return a;
				veh = v->next_hash;
			}

			if (x == x2)
				break;

			x = (x + 1) & 0x3F;
		}
		x = xb;

		if (y == y2)
			break;

		y = (y + 0x40) & ((0x3F) << 6);
	}
	return NULL;
}



void UpdateVehiclePosHash(Vehicle *v, int x, int y)
{
	VehicleID *old_hash, *new_hash;
	int old_x = v->left_coord;
	int old_y = v->top_coord;
	Vehicle *u;

	new_hash = (x == INVALID_COORD) ? NULL : &_vehicle_position_hash[GEN_HASH(x,y)];
	old_hash = (old_x == INVALID_COORD) ? NULL : &_vehicle_position_hash[GEN_HASH(old_x, old_y)];

	if (old_hash == new_hash)
		return;

	/* remove from hash table? */
	if (old_hash != NULL) {
		Vehicle *last = NULL;
		VehicleID idx = *old_hash;
		while ((u = GetVehicle(idx)) != v) {
			idx = u->next_hash;
			assert(idx != INVALID_VEHICLE);
			last = u;
		}

		if (last == NULL)
			*old_hash = v->next_hash;
		else
			last->next_hash = v->next_hash;
	}

	/* insert into hash table? */
	if (new_hash != NULL) {
		v->next_hash = *new_hash;
		*new_hash = v->index;
	}
}

void InitializeVehicles(void)
{
	int i;

	/* Clean the vehicle pool, and reserve enough blocks
	 *  for the special vehicles, plus one for all the other
	 *  vehicles (which is increased on-the-fly) */
	CleanPool(&_vehicle_pool);
	AddBlockToPool(&_vehicle_pool);
	for (i = 0; i < BLOCKS_FOR_SPECIAL_VEHICLES; i++)
		AddBlockToPool(&_vehicle_pool);

	// clear it...
	memset(_vehicle_position_hash, -1, sizeof(_vehicle_position_hash));
}

Vehicle *GetLastVehicleInChain(Vehicle *v)
{
	while (v->next != NULL) v = v->next;
	return v;
}

/** Finds the previous vehicle in a chain, by a brute force search.
 * This old function is REALLY slow because it searches through all vehicles to
 * find the previous vehicle, but if v->first has not been set, then this function
 * will need to be used to find the previous one. This function should never be
 * called by anything but GetFirstVehicleInChain
 */
static Vehicle *GetPrevVehicleInChain_bruteforce(const Vehicle *v)
{
	Vehicle *u;

	FOR_ALL_VEHICLES(u) if (u->type == VEH_Train && u->next == v) return u;

	return NULL;
}

/** Find the previous vehicle in a chain, by using the v->first cache.
 * While this function is fast, it cannot be used in the GetFirstVehicleInChain
 * function, otherwise you'll end up in an infinite loop call
 */
Vehicle *GetPrevVehicleInChain(const Vehicle *v)
{
	Vehicle *u;
	assert(v != NULL);

	u = GetFirstVehicleInChain(v);

 	// Check to see if this is the first
	if (v == u) return NULL;

	do {
		if (u->next == v) return u;
	} while ( ( u = u->next) != NULL);

	return NULL;
}

/** Finds the first vehicle in a chain.
 * This function reads out the v->first cache. Should the cache be dirty,
 * it determines the first vehicle in a chain, and updates the cache.
 */
Vehicle *GetFirstVehicleInChain(const Vehicle *v)
{
	Vehicle* u;

	assert(v != NULL);

	if (v->first != NULL) {
		if (v->first->subtype == TS_Front_Engine) return v->first;

		DEBUG(misc, 0) ("v->first cache faulty. We shouldn't be here, rebuilding cache!");
	}

	/* It is the fact (currently) that newly built vehicles do not have
	* their ->first pointer set. When this is the case, go up to the
	* first engine and set the pointers correctly. Also the first pointer
	* is not saved in a savegame, so this has to be fixed up after loading */

	/* Find the 'locomotive' or the first wagon in a chain */
	while ((u = GetPrevVehicleInChain_bruteforce(v)) != NULL) v = u;

	/* Set the first pointer of all vehicles in that chain to the first wagon */
	if (v->subtype == TS_Front_Engine)
		for (u = (Vehicle *)v; u != NULL; u = u->next) u->first = (Vehicle *)v;

	return (Vehicle*)v;
}

int CountVehiclesInChain(Vehicle *v)
{
	int count = 0;
	do count++; while ( (v=v->next) != NULL);
	return count;
}

void DeleteVehicle(Vehicle *v)
{
	DeleteName(v->string_id);
	v->type = 0;
	UpdateVehiclePosHash(v, INVALID_COORD, 0);
	v->next_hash = INVALID_VEHICLE;

	if (v->orders != NULL)
		DeleteVehicleOrders(v);
}

void DeleteVehicleChain(Vehicle *v)
{
	do {
		Vehicle *u = v;
		v = v->next;
		DeleteVehicle(u);
	} while (v != NULL);
}


void Aircraft_Tick(Vehicle *v);
void RoadVeh_Tick(Vehicle *v);
void Ship_Tick(Vehicle *v);
void Train_Tick(Vehicle *v);
static void EffectVehicle_Tick(Vehicle *v);
void DisasterVehicle_Tick(Vehicle *v);

VehicleTickProc *_vehicle_tick_procs[] = {
	Train_Tick,
	RoadVeh_Tick,
	Ship_Tick,
	Aircraft_Tick,
	EffectVehicle_Tick,
	DisasterVehicle_Tick,
};

void CallVehicleTicks(void)
{
	Vehicle *v;

	FOR_ALL_VEHICLES(v) {
		if (v->type != 0)
			_vehicle_tick_procs[v->type - 0x10](v);
	}
}

static bool CanFillVehicle_FullLoadAny(Vehicle *v)
{
	uint32 full = 0, not_full = 0;

	//special handling of aircraft

	//if the aircraft carries passengers and is NOT full, then
	//continue loading, no matter how much mail is in
	if ((v->type == VEH_Aircraft) && (v->cargo_type == CT_PASSENGERS) && (v->cargo_cap != v->cargo_count)) {
		return true;
	}

	// patch should return "true" to continue loading, i.e. when there is no cargo type that is fully loaded.
	do {
		//Should never happen, but just in case future additions change this
		assert(v->cargo_type<32);

		if (v->cargo_cap != 0) {
			uint32 mask = 1 << v->cargo_type;
			if (v->cargo_cap == v->cargo_count) full |= mask; else not_full |= mask;
		}
	} while ( (v=v->next) != NULL);

	// continue loading if there is a non full cargo type and no cargo type that is full
	return not_full && (full & ~not_full) == 0;
}

bool CanFillVehicle(Vehicle *v)
{
	TileIndex tile = v->tile;

	if (IsTileType(tile, MP_STATION) ||
			(v->type == VEH_Ship && (
				IsTileType(TILE_ADDXY(tile,  1,  0), MP_STATION) ||
				IsTileType(TILE_ADDXY(tile, -1,  0), MP_STATION) ||
				IsTileType(TILE_ADDXY(tile,  0,  1), MP_STATION) ||
				IsTileType(TILE_ADDXY(tile,  0, -1), MP_STATION) ||
				IsTileType(TILE_ADDXY(tile, -2,  0), MP_STATION)
			))) {

		// If patch is active, use alternative CanFillVehicle-function
		if (_patches.full_load_any)
			return CanFillVehicle_FullLoadAny(v);

		do {
			if (v->cargo_count != v->cargo_cap)
				return true;
		} while ( (v=v->next) != NULL);
	}
	return false;
}

/** Check if a given vehicle (type) can be refitted to a given cargo
 * @param *v vehicle to check
 * @param cid_to check refit to this cargo-type
 * @return true if it is possible, false otherwise
 */
bool CanRefitTo(const Vehicle *v, CargoID cid_to)
{
	CargoID cid = _global_cargo_id[_opt_ptr->landscape][cid_to];

	if (cid == GC_INVALID) return false;

	if (_engine_refit_masks[v->engine_type]) {
		if (!HASBIT(_engine_refit_masks[v->engine_type], cid)) return false;
	} else {
		/* If we are talking about normal vehicles (no newgrf), you can only refit engines */
		if (v->type == VEH_Train && (RailVehInfo(v->engine_type)->flags & RVI_WAGON)) return false;
		if (!HASBIT(_default_refitmasks[v->type - VEH_Train], cid)) return false;
	}

	return true;
}

static void DoDrawVehicle(const Vehicle *v)
{
	uint32 image = v->cur_image;

	if (v->vehstatus & VS_DISASTER) {
		MAKE_TRANSPARENT(image);
	} else if (v->vehstatus & VS_DEFPAL) {
		image |= (v->vehstatus & VS_CRASHED) ? PALETTE_CRASH : SPRITE_PALETTE(PLAYER_SPRITE_COLOR(v->owner));
	}

	AddSortableSpriteToDraw(image, v->x_pos + v->x_offs, v->y_pos + v->y_offs,
		v->sprite_width, v->sprite_height, v->z_height, v->z_pos);
}

void ViewportAddVehicles(DrawPixelInfo *dpi)
{
	int x,xb, y, x2, y2;
	VehicleID veh;
	Vehicle *v;

	x  = ((dpi->left - 70) & 0x1F80) >> 7;
	x2 = ((dpi->left + dpi->width) & 0x1F80) >> 7;

	y  = ((dpi->top - 70) & 0xFC0);
	y2 = ((dpi->top + dpi->height) & 0xFC0);

	for(;;) {
		xb = x;
		for(;;) {
			veh = _vehicle_position_hash[ (x+y)&0xFFFF ];
			while (veh != INVALID_VEHICLE) {
				v = GetVehicle(veh);

				if (!(v->vehstatus & VS_HIDDEN) &&
						dpi->left <= v->right_coord &&
						dpi->top <= v->bottom_coord &&
						dpi->left + dpi->width >= v->left_coord &&
						dpi->top + dpi->height >= v->top_coord) {
					DoDrawVehicle(v);
				}
				veh = v->next_hash;
			}

			if (x == x2)
				break;
			x = (x + 1) & 0x3F;
		}
		x = xb;

		if (y == y2)
			break;
		y = (y + 0x40) & ((0x3F) << 6);
	}
}

static void ChimneySmokeInit(Vehicle *v)
{
	uint32 r = Random();
	v->cur_image = SPR_CHIMNEY_SMOKE_0 + GB(r, 0, 3);
	v->progress = GB(r, 16, 3);
}

static void ChimneySmokeTick(Vehicle *v)
{
	if (v->progress > 0) {
		v->progress--;
	} else {
		TileIndex tile;

		BeginVehicleMove(v);

		tile = TileVirtXY(v->x_pos, v->y_pos);
		if (!IsTileType(tile, MP_INDUSTRY)) {
			EndVehicleMove(v);
			DeleteVehicle(v);
			return;
		}

		if (v->cur_image != SPR_CHIMNEY_SMOKE_7) {
			v->cur_image++;
		} else {
			v->cur_image = SPR_CHIMNEY_SMOKE_0;
		}
		v->progress = 7;
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	}
}

static void SteamSmokeInit(Vehicle *v)
{
	v->cur_image = SPR_STEAM_SMOKE_0;
	v->progress = 12;
}

static void SteamSmokeTick(Vehicle *v)
{
	bool moved = false;

	BeginVehicleMove(v);

	v->progress++;

	if ((v->progress & 7) == 0) {
		v->z_pos++;
		moved = true;
	}

	if ((v->progress & 0xF) == 4) {
		if (v->cur_image != SPR_STEAM_SMOKE_4) {
			v->cur_image++;
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
			return;
		}
		moved = true;
	}

	if (moved) {
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	}
}

static void DieselSmokeInit(Vehicle *v)
{
	v->cur_image = SPR_DIESEL_SMOKE_0;
	v->progress = 0;
}

static void DieselSmokeTick(Vehicle *v)
{
	v->progress++;

	if ((v->progress & 3) == 0) {
		BeginVehicleMove(v);
		v->z_pos++;
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	} else if ((v->progress & 7) == 1) {
		BeginVehicleMove(v);
		if (v->cur_image != SPR_DIESEL_SMOKE_5) {
			v->cur_image++;
			VehiclePositionChanged(v);
			EndVehicleMove(v);
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
		}
	}
}

static void ElectricSparkInit(Vehicle *v)
{
	v->cur_image = SPR_ELECTRIC_SPARK_0;
	v->progress = 1;
}

static void ElectricSparkTick(Vehicle *v)
{
	if (v->progress < 2) {
		v->progress++;
	} else {
		v->progress = 0;
		BeginVehicleMove(v);
		if (v->cur_image != SPR_ELECTRIC_SPARK_5) {
			v->cur_image++;
			VehiclePositionChanged(v);
			EndVehicleMove(v);
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
		}
	}
}

static void SmokeInit(Vehicle *v)
{
	v->cur_image = SPR_SMOKE_0;
	v->progress = 12;
}

static void SmokeTick(Vehicle *v)
{
	bool moved = false;

	BeginVehicleMove(v);

	v->progress++;

	if ((v->progress & 3) == 0) {
		v->z_pos++;
		moved = true;
	}

	if ((v->progress & 0xF) == 4) {
		if (v->cur_image != SPR_SMOKE_4) {
			v->cur_image++;
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
			return;
		}
		moved = true;
	}

	if (moved) {
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	}
}

static void ExplosionLargeInit(Vehicle *v)
{
	v->cur_image = SPR_EXPLOSION_LARGE_0;
	v->progress = 0;
}

static void ExplosionLargeTick(Vehicle *v)
{
	v->progress++;
	if ((v->progress & 3) == 0) {
		BeginVehicleMove(v);
		if (v->cur_image != SPR_EXPLOSION_LARGE_F) {
			v->cur_image++;
			VehiclePositionChanged(v);
			EndVehicleMove(v);
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
		}
	}
}

static void BreakdownSmokeInit(Vehicle *v)
{
	v->cur_image = SPR_BREAKDOWN_SMOKE_0;
	v->progress = 0;
}

static void BreakdownSmokeTick(Vehicle *v)
{
	v->progress++;
	if ((v->progress & 7) == 0) {
		BeginVehicleMove(v);
		if (v->cur_image != SPR_BREAKDOWN_SMOKE_3) {
			v->cur_image++;
		} else {
			v->cur_image = SPR_BREAKDOWN_SMOKE_0;
		}
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	}

	v->u.special.unk0--;
	if (v->u.special.unk0 == 0) {
		BeginVehicleMove(v);
		EndVehicleMove(v);
		DeleteVehicle(v);
	}
}

static void ExplosionSmallInit(Vehicle *v)
{
	v->cur_image = SPR_EXPLOSION_SMALL_0;
	v->progress = 0;
}

static void ExplosionSmallTick(Vehicle *v)
{
	v->progress++;
	if ((v->progress & 3) == 0) {
		BeginVehicleMove(v);
		if (v->cur_image != SPR_EXPLOSION_SMALL_B) {
			v->cur_image++;
			VehiclePositionChanged(v);
			EndVehicleMove(v);
		} else {
			EndVehicleMove(v);
			DeleteVehicle(v);
		}
	}
}

static void BulldozerInit(Vehicle *v)
{
	v->cur_image = SPR_BULLDOZER_NE;
	v->progress = 0;
	v->u.special.unk0 = 0;
	v->u.special.unk2 = 0;
}

typedef struct BulldozerMovement {
	byte direction:2;
	byte image:2;
	byte duration:3;
} BulldozerMovement;

static const BulldozerMovement _bulldozer_movement[] = {
	{ 0, 0, 4 },
	{ 3, 3, 4 },
	{ 2, 2, 7 },
	{ 0, 2, 7 },
	{ 1, 1, 3 },
	{ 2, 2, 7 },
	{ 0, 2, 7 },
	{ 1, 1, 3 },
	{ 2, 2, 7 },
	{ 0, 2, 7 },
	{ 3, 3, 6 },
	{ 2, 2, 6 },
	{ 1, 1, 7 },
	{ 3, 1, 7 },
	{ 0, 0, 3 },
	{ 1, 1, 7 },
	{ 3, 1, 7 },
	{ 0, 0, 3 },
	{ 1, 1, 7 },
	{ 3, 1, 7 }
};

static const struct {
	int8 x;
	int8 y;
} _inc_by_dir[] = {
	{ -1,  0 },
	{  0,  1 },
	{  1,  0 },
	{  0, -1 }
};

static void BulldozerTick(Vehicle *v)
{
	v->progress++;
	if ((v->progress & 7) == 0) {
		const BulldozerMovement* b = &_bulldozer_movement[v->u.special.unk0];

		BeginVehicleMove(v);

		v->cur_image = SPR_BULLDOZER_NE + b->image;

		v->x_pos += _inc_by_dir[b->direction].x;
		v->y_pos += _inc_by_dir[b->direction].y;

		v->u.special.unk2++;
		if (v->u.special.unk2 >= b->duration) {
			v->u.special.unk2 = 0;
			v->u.special.unk0++;
			if (v->u.special.unk0 == lengthof(_bulldozer_movement)) {
				EndVehicleMove(v);
				DeleteVehicle(v);
				return;
			}
		}
		VehiclePositionChanged(v);
		EndVehicleMove(v);
	}
}

static void BubbleInit(Vehicle *v)
{
	v->cur_image = SPR_BUBBLE_GENERATE_0;
	v->spritenum = 0;
	v->progress = 0;
}

typedef struct BubbleMovement {
	int8 x:4;
	int8 y:4;
	int8 z:4;
	byte image:4;
} BubbleMovement;

#define MK(x, y, z, i) { x, y, z, i }
#define ME(i) { i, 4, 0, 0 }

static const BubbleMovement _bubble_float_sw[] = {
	MK(0,0,1,0),
	MK(1,0,1,1),
	MK(0,0,1,0),
	MK(1,0,1,2),
	ME(1)
};


static const BubbleMovement _bubble_float_ne[] = {
	MK(0,0,1,0),
	MK(-1,0,1,1),
	MK(0,0,1,0),
	MK(-1,0,1,2),
	ME(1)
};

static const BubbleMovement _bubble_float_se[] = {
	MK(0,0,1,0),
	MK(0,1,1,1),
	MK(0,0,1,0),
	MK(0,1,1,2),
	ME(1)
};

static const BubbleMovement _bubble_float_nw[] = {
	MK(0,0,1,0),
	MK(0,-1,1,1),
	MK(0,0,1,0),
	MK(0,-1,1,2),
	ME(1)
};

static const BubbleMovement _bubble_burst[] = {
	MK(0,0,1,2),
	MK(0,0,1,7),
	MK(0,0,1,8),
	MK(0,0,1,9),
	ME(0)
};

static const BubbleMovement _bubble_absorb[] = {
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(0,0,1,0),
	MK(0,0,1,2),
	MK(0,0,1,0),
	MK(0,0,1,1),
	MK(2,1,3,0),
	MK(1,1,3,1),
	MK(2,1,3,0),
	MK(1,1,3,2),
	MK(2,1,3,0),
	MK(1,1,3,1),
	MK(2,1,3,0),
	MK(1,0,1,2),
	MK(0,0,1,0),
	MK(1,0,1,1),
	MK(0,0,1,0),
	MK(1,0,1,2),
	MK(0,0,1,0),
	MK(1,0,1,1),
	MK(0,0,1,0),
	MK(1,0,1,2),
	ME(2),
	MK(0,0,0,0xA),
	MK(0,0,0,0xB),
	MK(0,0,0,0xC),
	MK(0,0,0,0xD),
	MK(0,0,0,0xE),
	ME(0)
};
#undef ME
#undef MK

static const BubbleMovement * const _bubble_movement[] = {
	_bubble_float_sw,
	_bubble_float_ne,
	_bubble_float_se,
	_bubble_float_nw,
	_bubble_burst,
	_bubble_absorb,
};

static void BubbleTick(Vehicle *v)
{
	/*
	 * Warning: those effects can NOT use Random(), and have to use
	 *  InteractiveRandom(), because somehow someone forgot to save
	 *  spritenum to the savegame, and so it will cause desyncs in
	 *  multiplayer!! (that is: in ToyLand)
	 */
	uint et;
	const BubbleMovement *b;

	v->progress++;
	if ((v->progress & 3) != 0)
		return;

	BeginVehicleMove(v);

	if (v->spritenum == 0) {
		v->cur_image++;
		if (v->cur_image < SPR_BUBBLE_GENERATE_3) {
			VehiclePositionChanged(v);
			EndVehicleMove(v);
			return;
		}
		if (v->u.special.unk2 != 0) {
			v->spritenum = (InteractiveRandom() & 3) + 1;
		} else {
			v->spritenum = 6;
		}
		et = 0;
	} else {
		et = v->engine_type + 1;
	}

	b = &_bubble_movement[v->spritenum - 1][et];

	if (b->y == 4 && b->x == 0) {
		EndVehicleMove(v);
		DeleteVehicle(v);
		return;
	}

	if (b->y == 4 && b->x == 1) {
		if (v->z_pos > 180 || CHANCE16I(1, 96, InteractiveRandom())) {
			v->spritenum = 5;
			SndPlayVehicleFx(SND_2F_POP, v);
		}
		et = 0;
	}

	if (b->y == 4 && b->x == 2) {
		TileIndex tile;

		et++;
		SndPlayVehicleFx(SND_31_EXTRACT, v);

		tile = TileVirtXY(v->x_pos, v->y_pos);
		if (IsTileType(tile, MP_INDUSTRY) && _m[tile].m5 == 0xA2) AddAnimatedTile(tile);
	}

	v->engine_type = et;
	b = &_bubble_movement[v->spritenum - 1][et];

	v->x_pos += b->x;
	v->y_pos += b->y;
	v->z_pos += b->z;
	v->cur_image = SPR_BUBBLE_0 + b->image;

	VehiclePositionChanged(v);
	EndVehicleMove(v);
}


typedef void EffectInitProc(Vehicle *v);
typedef void EffectTickProc(Vehicle *v);

static EffectInitProc * const _effect_init_procs[] = {
	ChimneySmokeInit,
	SteamSmokeInit,
	DieselSmokeInit,
	ElectricSparkInit,
	SmokeInit,
	ExplosionLargeInit,
	BreakdownSmokeInit,
	ExplosionSmallInit,
	BulldozerInit,
	BubbleInit,
};

static EffectTickProc * const _effect_tick_procs[] = {
	ChimneySmokeTick,
	SteamSmokeTick,
	DieselSmokeTick,
	ElectricSparkTick,
	SmokeTick,
	ExplosionLargeTick,
	BreakdownSmokeTick,
	ExplosionSmallTick,
	BulldozerTick,
	BubbleTick,
};


Vehicle *CreateEffectVehicle(int x, int y, int z, EffectVehicle type)
{
	Vehicle *v;

	v = ForceAllocateSpecialVehicle();
	if (v != NULL) {
		v->type = VEH_Special;
		v->subtype = type;
		v->x_pos = x;
		v->y_pos = y;
		v->z_pos = z;
		v->z_height = v->sprite_width = v->sprite_height = 1;
		v->x_offs = v->y_offs = 0;
		v->tile = 0;
		v->vehstatus = VS_UNCLICKABLE;

		_effect_init_procs[type](v);

		VehiclePositionChanged(v);
		BeginVehicleMove(v);
		EndVehicleMove(v);
	}
	return v;
}

Vehicle *CreateEffectVehicleAbove(int x, int y, int z, EffectVehicle type)
{
	return CreateEffectVehicle(x, y, GetSlopeZ(x, y) + z, type);
}

Vehicle *CreateEffectVehicleRel(const Vehicle *v, int x, int y, int z, EffectVehicle type)
{
	return CreateEffectVehicle(v->x_pos + x, v->y_pos + y, v->z_pos + z, type);
}

static void EffectVehicle_Tick(Vehicle *v)
{
	_effect_tick_procs[v->subtype](v);
}

Vehicle *CheckClickOnVehicle(const ViewPort *vp, int x, int y)
{
	Vehicle *found = NULL, *v;
	uint dist, best_dist = (uint)-1;

	if ( (uint)(x -= vp->left) >= (uint)vp->width ||
			 (uint)(y -= vp->top) >= (uint)vp->height)
				return NULL;

	x = (x << vp->zoom) + vp->virtual_left;
	y = (y << vp->zoom) + vp->virtual_top;

	FOR_ALL_VEHICLES(v) {
		if (v->type != 0 && (v->vehstatus & (VS_HIDDEN|VS_UNCLICKABLE)) == 0 &&
				x >= v->left_coord && x <= v->right_coord &&
				y >= v->top_coord && y <= v->bottom_coord) {

			dist = max(
				myabs( ((v->left_coord + v->right_coord)>>1) - x ),
				myabs( ((v->top_coord + v->bottom_coord)>>1) - y )
			);

			if (dist < best_dist) {
				found = v;
				best_dist = dist;
			}
		}
	}

	return found;
}


void DecreaseVehicleValue(Vehicle *v)
{
	v->value -= v->value >> 8;
	InvalidateWindow(WC_VEHICLE_DETAILS, v->index);
}

static const byte _breakdown_chance[64] = {
	3, 3, 3, 3, 3, 3, 3, 3,
	4, 4, 5, 5, 6, 6, 7, 7,
	8, 8, 9, 9, 10, 10, 11, 11,
	12, 13, 13, 13, 13, 14, 15, 16,
	17, 19, 21, 25, 28, 31, 34, 37,
	40, 44, 48, 52, 56, 60, 64, 68,
	72, 80, 90, 100, 110, 120, 130, 140,
	150, 170, 190, 210, 230, 250, 250, 250,
};

void CheckVehicleBreakdown(Vehicle *v)
{
	int rel, rel_old;
	uint32 r;
	int chance;

	/* decrease reliability */
	v->reliability = rel = max((rel_old = v->reliability) - v->reliability_spd_dec, 0);
	if ((rel_old >> 8) != (rel >> 8))
		InvalidateWindow(WC_VEHICLE_DETAILS, v->index);

	if (v->breakdown_ctr != 0 || (v->vehstatus & VS_STOPPED) != 0 ||
			v->cur_speed < 5 || _game_mode == GM_MENU)
				return;

	r = Random();

	/* increase chance of failure */
	chance = v->breakdown_chance + 1;
	if (CHANCE16I(1,25,r)) chance += 25;
	v->breakdown_chance = min(255, chance);

	/* calculate reliability value to use in comparison */
	rel = v->reliability;
	if (v->type == VEH_Ship) rel += 0x6666;

	/* disabled breakdowns? */
	if (_opt.diff.vehicle_breakdowns < 1)
		return;

	/* reduced breakdowns? */
	if (_opt.diff.vehicle_breakdowns == 1) rel += 0x6666;

	/* check if to break down */
	if (_breakdown_chance[(uint)min(rel, 0xffff) >> 10] <= v->breakdown_chance) {
		v->breakdown_ctr    = GB(r, 16, 6) + 0x3F;
		v->breakdown_delay  = GB(r, 24, 7) + 0x80;
		v->breakdown_chance = 0;
	}
}

static const StringID _vehicle_type_names[4] = {
	STR_019F_TRAIN,
	STR_019C_ROAD_VEHICLE,
	STR_019E_SHIP,
	STR_019D_AIRCRAFT,
};

static void ShowVehicleGettingOld(Vehicle *v, StringID msg)
{
	if (v->owner != _local_player)
		return;

	// Do not show getting-old message if autorenew is active
	if (GetPlayer(v->owner)->engine_renew)
		return;

	SetDParam(0, _vehicle_type_names[v->type - 0x10]);
	SetDParam(1, v->unitnumber);
	AddNewsItem(msg, NEWS_FLAGS(NM_SMALL, NF_VIEWPORT|NF_VEHICLE, NT_ADVICE, 0), v->index, 0);
}

void AgeVehicle(Vehicle *v)
{
	int age;

	if (v->age < 65535)
		v->age++;

	age = v->age - v->max_age;
	if (age == 366*0 || age == 366*1 || age == 366*2 || age == 366*3 || age == 366*4)
		v->reliability_spd_dec <<= 1;

	InvalidateWindow(WC_VEHICLE_DETAILS, v->index);

	if (age == -366) {
		ShowVehicleGettingOld(v, STR_01A0_IS_GETTING_OLD);
	} else if (age == 0) {
		ShowVehicleGettingOld(v, STR_01A1_IS_GETTING_VERY_OLD);
	} else if (age == 366*1 || age == 366*2 || age == 366*3 || age == 366*4 || age == 366*5) {
		ShowVehicleGettingOld(v, STR_01A2_IS_GETTING_VERY_OLD_AND);
	}
}

extern int32 EstimateTrainCost(const RailVehicleInfo *rvi);
extern int32 EstimateRoadVehCost(EngineID engine_type);
extern int32 EstimateShipCost(EngineID engine_type);
extern int32 EstimateAircraftCost(EngineID engine_type);
extern int32 CmdRefitRailVehicle(int x, int y, uint32 flags, uint32 p1, uint32 p2);
extern int32 CmdRefitShip(int x, int y, uint32 flags, uint32 p1, uint32 p2);
extern int32 CmdRefitAircraft(int x, int y, uint32 flags, uint32 p1, uint32 p2);

int32 CmdCloneOrder(int x, int y, uint32 flags, uint32 veh1_veh2, uint32 mode);
int32 CmdMoveRailVehicle(int x, int y, uint32 flags, uint32 p1, uint32 p2);
int32 CmdBuildRailVehicle(int x, int y, uint32 flags, uint32 p1, uint32 p2);
int32 CmdBuildRoadVeh(int x, int y, uint32 flags, uint32 p1, uint32 p2);
int32 CmdBuildShip(int x, int y, uint32 flags, uint32 p1, uint32 p2);
int32 CmdBuildAircraft(int x, int y, uint32 flags, uint32 p1, uint32 p2);

typedef int32 VehBuildProc(int x, int y, uint32 flags, uint32 p1, uint32 p2);

static VehBuildProc * const _veh_build_cmd_table[] = {
	CmdBuildRailVehicle,
	CmdBuildRoadVeh,
	CmdBuildShip,
	CmdBuildAircraft,
};

static VehicleID * _new_vehicle_id_proc_table[] = {
	&_new_train_id,
	&_new_roadveh_id,
	&_new_ship_id,
	&_new_aircraft_id,
};

/** Clone a vehicle. If it is a train, it will clone all the cars too
  * @param x,y unused
  * @param p1 the original vehicle's index
  * @param p2 1 = shared orders, else copied orders
  */
int32 CmdCloneVehicle(int x, int y, uint32 flags, uint32 p1, uint32 p2)
{
	Vehicle *vfront, *v;
	Vehicle *wfront, *w1, *w2;
	int cost, total_cost;
	VehBuildProc *proc;
	VehicleID *new_id;
	uint refit_command = 0;
	byte needs_refitting = 255;

	if (!IsVehicleIndex(p1))
		return CMD_ERROR;
	v = GetVehicle(p1);
	wfront = v;
	w1 = v;
	vfront = v;

	if (!CheckOwnership(v->owner))
		return CMD_ERROR;

	if (v->type == VEH_Train && v->subtype != TS_Front_Engine) return CMD_ERROR;

	//no need to check if it is a depot since the build command do that
	switch (v->type) {
		case VEH_Train:		refit_command = CMD_REFIT_RAIL_VEHICLE; break;
		case VEH_Road:		break;
		case VEH_Ship:		refit_command = CMD_REFIT_SHIP; break;
		case VEH_Aircraft:	refit_command = CMD_REFIT_AIRCRAFT; break;
		default: return CMD_ERROR;
	}

	proc = _veh_build_cmd_table[v->type - VEH_Train];
	new_id = _new_vehicle_id_proc_table[v->type - VEH_Train];
	total_cost = proc(x, y, flags, v->engine_type, 3);
	if (total_cost == CMD_ERROR)
		return CMD_ERROR;

	if (flags & DC_EXEC) {
		wfront = GetVehicle(*new_id);
		w1 = wfront;
		CmdCloneOrder(x, y, flags, (v->index << 16) | w1->index, p2 & 1 ? CO_SHARE : CO_COPY);

		if (wfront->cargo_type != v->cargo_type) {
			//a refit is needed
			needs_refitting = v->cargo_type;
		}
	}
	if (v->type == VEH_Train) {
		// now we handle the cars
		v = v->next;
		while (v != NULL) {
			cost = proc(x, y, flags, v->engine_type, 3);
			if (cost == CMD_ERROR)
				return CMD_ERROR;
			total_cost += cost;

			if (flags & DC_EXEC) {
				// add this unit to the end of the train
				w2 = GetVehicle(RailVehInfo(v->engine_type)->flags & RVI_WAGON ? _new_wagon_id : _new_train_id);
				CmdMoveRailVehicle(x, y, flags, (w1->index << 16) | w2->index, 0);
				w1 = w2;
			}
			v = v->next;
		}

		if (flags & DC_EXEC) {
			_new_train_id = wfront->index;
			v = vfront;
			w1 = wfront;
			while (w1 != NULL && v != NULL) {
				w1->spritenum = v->spritenum; // makes sure that multiheaded engines are facing the correct way
				if (w1->cargo_type != v->cargo_type)	// checks if a refit is needed
					needs_refitting = v->cargo_type;
				w1 = w1->next;
				v = v->next;
			}

		}
	}
	if (flags & DC_EXEC && needs_refitting != 255 && vfront->type != VEH_Road) {	// right now we do not refit road vehicles
		if (DoCommandByTile(wfront->tile, wfront->index, needs_refitting, 0, refit_command) != CMD_ERROR)
			DoCommandByTile(wfront->tile, wfront->index, needs_refitting, DC_EXEC, refit_command);
	}
	return total_cost;
}

/* Replaces a vehicle (used to be called autorenew)
 * This function is only called from MaybeReplaceVehicle(), which is the next one
 * Must be called with _current_player set to the owner of the vehicle
 * @param w Vehicle to replace
 * @param flags is the flags to use when calling DoCommand(). Mainly DC_EXEC counts
 *	  return value is cost of the replacement or CMD_ERROR
 */
static int32 ReplaceVehicle(Vehicle **w, byte flags)
{
	int32 cost;
	const Vehicle *old_v = *w;
	const Player *p = GetPlayer(old_v->owner);
	EngineID new_engine_type;
	const UnitID cached_unitnumber = old_v->unitnumber;
	bool new_front = false;
	Vehicle *new_v = NULL;

	new_engine_type = p->engine_replacement[old_v->engine_type] == INVALID_ENGINE ? old_v->engine_type: p->engine_replacement[old_v->engine_type];

	cost = DoCommand(old_v->x_pos, old_v->y_pos, new_engine_type, 2, flags, CMD_BUILD_VEH(old_v->type));

	//check if the new engine is buildable
	if (CmdFailed(cost)) return cost;

	if (flags & DC_EXEC) {
		new_v = GetVehicle(*_new_vehicle_id_proc_table[old_v->type - VEH_Train]);
		*w = new_v;

		/* refit if needed */
		if (new_v->type != VEH_Road) { // road vehicles can't be refitted
			if (old_v->cargo_type != new_v->cargo_type && old_v->cargo_cap != 0 && new_v->cargo_cap != 0) {// some train engines do not have cargo capacity
				DoCommand(0, 0, new_v->index, old_v->cargo_type, DC_EXEC, CMD_REFIT_VEH(new_v->type));
			}
		}

		/* move the cargo to the new vehicle */
		if (old_v->cargo_type == new_v->cargo_type && old_v->cargo_count != 0) {
			// move the cargo to the new vehicle
			new_v->cargo_count = min(old_v->cargo_count, new_v->cargo_cap);
			new_v->cargo_source = old_v->cargo_source;

			// copy the age of the cargo
			new_v->cargo_days = old_v->cargo_days;
			new_v->day_counter = old_v->day_counter;
			new_v->tick_counter = old_v->tick_counter;
		}

		if (old_v->type == VEH_Train && old_v->u.rail.first_engine != INVALID_VEHICLE) {
			/* this is a railcar. We need to move the car into the train
			 * We add the new engine after the old one instead of replacing it. It will give the same result anyway when we
			 * sell the old engine in a moment
			 */
			DoCommand(0, 0, (old_v->index << 16) | new_v->index, 1, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);
		} else {
			// copy/clone the orders
			DoCommand(0, 0, (old_v->index << 16) | new_v->index, IsOrderListShared(old_v) ? CO_SHARE : CO_COPY, DC_EXEC, CMD_CLONE_ORDER);
			new_v->cur_order_index = old_v->cur_order_index;
			ChangeVehicleViewWindow(old_v, new_v);
			new_front = true;

			new_v->current_order = old_v->current_order;
			if (old_v->type == VEH_Train){
				// move the entire train to the new engine, including the old engine. It will be sold in a moment anyway
				DoCommand(0, 0, (new_v->index << 16) | old_v->index, 1, DC_EXEC, CMD_MOVE_RAIL_VEHICLE);
			}
		}
	}

	// sell the engine/ find out how much you get for the old engine
	cost += DoCommand(0, 0, old_v->index, 0, flags, CMD_SELL_VEH(old_v->type));

	if (new_front) {
		// now we assign the old unitnumber to the new vehicle
		new_v->unitnumber = cached_unitnumber;
	}

	return cost;
}

/** replaces a vehicle if it's set for autoreplace or is too old(used to be called autorenew)
* @param v The vehicle to replace
*	if the vehicle is a train, v needs to be the front engine
*	return value is a pointer to the new vehicle, which is the same as the argument if nothing happened
*/
Vehicle * MaybeReplaceVehicle(Vehicle *v)
{
	Vehicle *w;
	const Player *p = GetPlayer(v->owner);
	byte flags = 0;
	int32 cost = 0, temp_cost = 0;

	_current_player = v->owner;

	assert(v->type == VEH_Train || v->type == VEH_Road || v->type == VEH_Ship || v->type == VEH_Aircraft);

	DoCommand(0, 0, v->index, 0, DC_EXEC, CMD_STARTSTOP_VEH(v->type));

	while (true) {
		w = v;
		do {
			// check if the vehicle should be replaced
			if (!p->engine_renew || w->age - w->max_age < (p->engine_renew_months * 30)		//replace if engine is too old
				|| (w->max_age == 0)) {														// rail cars got a max age of 0
				if (p->engine_replacement[w->engine_type] == INVALID_ENGINE)				// updates to a new model
					continue;
			}

			/* if we are looking at the rear end of a multiheaded locomotive, skip it */
			if (w->type == VEH_Train) {
				const RailVehicleInfo *rvi = RailVehInfo(w->engine_type);
				if (rvi->flags & RVI_MULTIHEAD && rvi->image_index == w->spritenum - 1)
					continue;
			}

			/* Now replace the vehicle */
			temp_cost = ReplaceVehicle(&w, flags);

			if (flags & DC_EXEC && !(w->type == VEH_Train && w->u.rail.first_engine != INVALID_VEHICLE)){
				// now we bought a new engine and sold the old one. We need to fix the pointers in order to avoid pointing to the old one
				// for trains: these pointers should point to the front engine and not the cars
				v = w;
			}

			if (CmdFailed(temp_cost))
				break;

			cost += temp_cost;
		} while (w->type == VEH_Train && (w=w->next) != NULL);

		if (!(flags & DC_EXEC) && (CmdFailed(temp_cost) || p->money64 < (int32)(cost + p->engine_renew_money) || cost == 0)) {
			if (p->money64 < (int32)(cost + p->engine_renew_money) && ( _local_player == v->owner ) && cost != 0) {
				StringID message;
				SetDParam(0, v->unitnumber);
				switch (v->type) {
					case VEH_Train:    message = STR_TRAIN_AUTORENEW_FAILED;       break;
					case VEH_Road:     message = STR_ROADVEHICLE_AUTORENEW_FAILED; break;
					case VEH_Ship:     message = STR_SHIP_AUTORENEW_FAILED;        break;
					case VEH_Aircraft: message = STR_AIRCRAFT_AUTORENEW_FAILED;    break;
						// This should never happen
					default: NOT_REACHED(); message = 0; break;
				}

				AddNewsItem(message, NEWS_FLAGS(NM_SMALL, NF_VIEWPORT|NF_VEHICLE, NT_ADVICE, 0), v->index, 0);
			}
			DoCommand(0, 0, v->index, 0, DC_EXEC, CMD_STARTSTOP_VEH(v->type));	//we start the vehicle again
			return v;
		}

		if (flags & DC_EXEC) {
			break;	// we are done replacing since the loop ran once with DC_EXEC
		}
		// now we redo the loop, but this time we actually do stuff since we know that we can do it
		flags |= DC_EXEC;
	}

	SET_EXPENSES_TYPE(EXPENSES_NEW_VEHICLES);
	SubtractMoneyFromPlayer(cost);
	if (IsLocalPlayer()) ShowCostOrIncomeAnimation(v->x_pos, v->y_pos, v->z_pos, cost);

	DoCommand(0, 0, v->index, 0, DC_EXEC, CMD_STARTSTOP_VEH(v->type));	//we start the vehicle again
	_current_player = OWNER_NONE;
	return v;
}


/** Give a custom name to your vehicle
 * @param x,y unused
 * @param p1 vehicle ID to name
 * @param p2 unused
 */
int32 CmdNameVehicle(int x, int y, uint32 flags, uint32 p1, uint32 p2)
{
	Vehicle *v;
	StringID str;

	if (!IsVehicleIndex(p1) || _cmd_text[0] == '\0') return CMD_ERROR;

	v = GetVehicle(p1);

	if (!CheckOwnership(v->owner)) return CMD_ERROR;

	str = AllocateNameUnique(_cmd_text, 2);
	if (str == 0) return CMD_ERROR;

	if (flags & DC_EXEC) {
		StringID old_str = v->string_id;
		v->string_id = str;
		DeleteName(old_str);
		ResortVehicleLists();
		MarkWholeScreenDirty();
	} else {
		DeleteName(str);
	}

	return 0;
}



static Rect _old_vehicle_coords;

void BeginVehicleMove(Vehicle *v) {
	_old_vehicle_coords.left = v->left_coord;
	_old_vehicle_coords.top = v->top_coord;
	_old_vehicle_coords.right = v->right_coord;
	_old_vehicle_coords.bottom = v->bottom_coord;
}

void EndVehicleMove(Vehicle *v)
{
	MarkAllViewportsDirty(
		min(_old_vehicle_coords.left,v->left_coord),
		min(_old_vehicle_coords.top,v->top_coord),
		max(_old_vehicle_coords.right,v->right_coord)+1,
		max(_old_vehicle_coords.bottom,v->bottom_coord)+1
	);
}

/* returns true if staying in the same tile */
bool GetNewVehiclePos(const Vehicle *v, GetNewVehiclePosResult *gp)
{
	static const int8 _delta_coord[16] = {
		-1,-1,-1, 0, 1, 1, 1, 0, /* x */
		-1, 0, 1, 1, 1, 0,-1,-1, /* y */
	};

	int x = v->x_pos + _delta_coord[v->direction];
	int y = v->y_pos + _delta_coord[v->direction + 8];

	gp->x = x;
	gp->y = y;
	gp->old_tile = v->tile;
	gp->new_tile = TileVirtXY(x, y);
	return gp->old_tile == gp->new_tile;
}

static const byte _new_direction_table[9] = {
	0, 7, 6,
	1, 3, 5,
	2, 3, 4,
};

byte GetDirectionTowards(const Vehicle *v, int x, int y)
{
	byte dirdiff, dir;
	int i = 0;

	if (y >= v->y_pos) {
		if (y != v->y_pos) i+=3;
		i+=3;
	}

	if (x >= v->x_pos) {
		if (x != v->x_pos) i++;
		i++;
	}

	dir = v->direction;

	dirdiff = _new_direction_table[i] - dir;
	if (dirdiff == 0)
		return dir;
	return (dir+((dirdiff&7)<5?1:-1)) & 7;
}

Trackdir GetVehicleTrackdir(const Vehicle* v)
{
	if (v->vehstatus & VS_CRASHED) return 0xFF;

	switch(v->type)
	{
		case VEH_Train:
			if (v->u.rail.track == 0x80) /* We'll assume the train is facing outwards */
				return DiagdirToDiagTrackdir(GetDepotDirection(v->tile, TRANSPORT_RAIL)); /* Train in depot */

			if (v->u.rail.track == 0x40) /* train in tunnel, so just use his direction and assume a diagonal track */
				return DiagdirToDiagTrackdir((v->direction >> 1) & 3);

			return TrackDirectionToTrackdir(FIND_FIRST_BIT(v->u.rail.track),v->direction);

		case VEH_Ship:
			if (v->u.ship.state == 0x80)  /* Inside a depot? */
				/* We'll assume the ship is facing outwards */
				return DiagdirToDiagTrackdir(GetDepotDirection(v->tile, TRANSPORT_WATER)); /* Ship in depot */

			return TrackDirectionToTrackdir(FIND_FIRST_BIT(v->u.ship.state),v->direction);

		case VEH_Road:
			if (v->u.road.state == 254) /* We'll assume the road vehicle is facing outwards */
				return DiagdirToDiagTrackdir(GetDepotDirection(v->tile, TRANSPORT_ROAD)); /* Road vehicle in depot */

			if (IsRoadStationTile(v->tile)) /* We'll assume the road vehicle is facing outwards */
				return DiagdirToDiagTrackdir(GetRoadStationDir(v->tile)); /* Road vehicle in a station */

			return DiagdirToDiagTrackdir((v->direction >> 1) & 3);

		/* case VEH_Aircraft: case VEH_Special: case VEH_Disaster: */
		default: return 0xFF;
	}
}
/* Return value has bit 0x2 set, when the vehicle enters a station. Then,
 * result << 8 contains the id of the station entered. If the return value has
 * bit 0x8 set, the vehicle could not and did not enter the tile. Are there
 * other bits that can be set? */
uint32 VehicleEnterTile(Vehicle *v, TileIndex tile, int x, int y)
{
	TileIndex old_tile = v->tile;
	uint32 result = _tile_type_procs[GetTileType(tile)]->vehicle_enter_tile_proc(v, tile, x, y);

	/* When vehicle_enter_tile_proc returns 8, that apparently means that
	 * we cannot enter the tile at all. In that case, don't call
	 * leave_tile. */
	if (!(result & 8) && old_tile != tile) {
		VehicleLeaveTileProc *proc = _tile_type_procs[GetTileType(old_tile)]->vehicle_leave_tile_proc;
		if (proc != NULL)
			proc(v, old_tile, x, y);
	}
	return result;
}

UnitID GetFreeUnitNumber(byte type)
{
	UnitID unit_num = 0;
	Vehicle *u;

restart:
	unit_num++;
	FOR_ALL_VEHICLES(u) {
		if (u->type == type && u->owner == _current_player &&
		    unit_num == u->unitnumber)
					goto restart;
	}
	return unit_num;
}


// Save and load of vehicles
const SaveLoad _common_veh_desc[] = {
	SLE_VAR(Vehicle,subtype,					SLE_UINT8),

	SLE_REF(Vehicle,next,							REF_VEHICLE_OLD),
	SLE_VAR(Vehicle,string_id,				SLE_STRINGID),
	SLE_CONDVAR(Vehicle,unitnumber,				SLE_FILE_U8 | SLE_VAR_U16, 0, 7),
	SLE_CONDVAR(Vehicle,unitnumber,				SLE_UINT16, 8, 255),
	SLE_VAR(Vehicle,owner,						SLE_UINT8),
	SLE_CONDVAR(Vehicle,tile,					SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,tile,					SLE_UINT32, 6, 255),
	SLE_CONDVAR(Vehicle,dest_tile,		SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,dest_tile,		SLE_UINT32, 6, 255),

	SLE_CONDVAR(Vehicle,x_pos,				SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,x_pos,				SLE_UINT32, 6, 255),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_UINT32, 6, 255),
	SLE_VAR(Vehicle,z_pos,						SLE_UINT8),
	SLE_VAR(Vehicle,direction,				SLE_UINT8),

	SLE_VAR(Vehicle,cur_image,				SLE_UINT16),
	SLE_VAR(Vehicle,spritenum,				SLE_UINT8),
	SLE_VAR(Vehicle,sprite_width,			SLE_UINT8),
	SLE_VAR(Vehicle,sprite_height,		SLE_UINT8),
	SLE_VAR(Vehicle,z_height,					SLE_UINT8),
	SLE_VAR(Vehicle,x_offs,						SLE_INT8),
	SLE_VAR(Vehicle,y_offs,						SLE_INT8),
	SLE_VAR(Vehicle,engine_type,			SLE_UINT16),

	SLE_VAR(Vehicle,max_speed,				SLE_UINT16),
	SLE_VAR(Vehicle,cur_speed,				SLE_UINT16),
	SLE_VAR(Vehicle,subspeed,					SLE_UINT8),
	SLE_VAR(Vehicle,acceleration,			SLE_UINT8),
	SLE_VAR(Vehicle,progress,					SLE_UINT8),

	SLE_VAR(Vehicle,vehstatus,				SLE_UINT8),
	SLE_CONDVAR(Vehicle,last_station_visited, SLE_FILE_U8 | SLE_VAR_U16, 0, 4),
	SLE_CONDVAR(Vehicle,last_station_visited, SLE_UINT16, 5, 255),

	SLE_VAR(Vehicle,cargo_type,				SLE_UINT8),
	SLE_VAR(Vehicle,cargo_days,				SLE_UINT8),
	SLE_CONDVAR(Vehicle,cargo_source,			SLE_FILE_U8 | SLE_VAR_U16, 0, 6),
	SLE_CONDVAR(Vehicle,cargo_source,			SLE_UINT16, 7, 255),
	SLE_VAR(Vehicle,cargo_cap,				SLE_UINT16),
	SLE_VAR(Vehicle,cargo_count,			SLE_UINT16),

	SLE_VAR(Vehicle,day_counter,			SLE_UINT8),
	SLE_VAR(Vehicle,tick_counter,			SLE_UINT8),

	SLE_VAR(Vehicle,cur_order_index,	SLE_UINT8),
	SLE_VAR(Vehicle,num_orders,				SLE_UINT8),

	/* This next line is for version 4 and prior compatibility.. it temporarily reads
	    type and flags (which were both 4 bits) into type. Later on this is
	    converted correctly */
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, type),    SLE_UINT8,  0, 4),
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, station), SLE_FILE_U8 | SLE_VAR_U16, 0, 4),

	/* Orders for version 5 and on */
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, type),    SLE_UINT8,  5, 255),
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, flags),   SLE_UINT8,  5, 255),
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, station), SLE_UINT16, 5, 255),

	SLE_REF(Vehicle,orders,						REF_ORDER),

	SLE_VAR(Vehicle,age,							SLE_UINT16),
	SLE_VAR(Vehicle,max_age,					SLE_UINT16),
	SLE_VAR(Vehicle,date_of_last_service,SLE_UINT16),
	SLE_VAR(Vehicle,service_interval,	SLE_UINT16),
	SLE_VAR(Vehicle,reliability,			SLE_UINT16),
	SLE_VAR(Vehicle,reliability_spd_dec,SLE_UINT16),
	SLE_VAR(Vehicle,breakdown_ctr,		SLE_UINT8),
	SLE_VAR(Vehicle,breakdown_delay,	SLE_UINT8),
	SLE_VAR(Vehicle,breakdowns_since_last_service,	SLE_UINT8),
	SLE_VAR(Vehicle,breakdown_chance,	SLE_UINT8),
	SLE_VAR(Vehicle,build_year,				SLE_UINT8),

	SLE_VAR(Vehicle,load_unload_time_rem,	SLE_UINT16),

	SLE_VAR(Vehicle,profit_this_year,	SLE_INT32),
	SLE_VAR(Vehicle,profit_last_year,	SLE_INT32),
	SLE_VAR(Vehicle,value,						SLE_UINT32),

	SLE_VAR(Vehicle,random_bits,       SLE_UINT8),
	SLE_VAR(Vehicle,waiting_triggers,  SLE_UINT8),

	SLE_REF(Vehicle,next_shared,				REF_VEHICLE),
	SLE_REF(Vehicle,prev_shared,				REF_VEHICLE),

	// reserve extra space in savegame here. (currently 10 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U8 | SLE_VAR_NULL, 2, 2, 255), /* 2 */
	SLE_CONDARR(NullStruct,null,SLE_FILE_U32 | SLE_VAR_NULL, 2, 2, 255), /* 8 */

	SLE_END()
};


static const SaveLoad _train_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Train, 0), // Train type. VEH_Train in mem, 0 in file.
	SLE_INCLUDEX(0, INC_VEHICLE_COMMON),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRail,crash_anim_pos), SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRail,force_proceed), SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRail,railtype), SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRail,track), SLE_UINT8),

	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRail,flags), SLE_UINT8, 2, 255),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRail,days_since_order_progr), SLE_UINT16, 2, 255),

	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRail,pbs_status), SLE_UINT8, 2, 255),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRail,pbs_end_tile), SLE_UINT32, 2, 255),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRail,pbs_end_trackdir), SLE_UINT8, 2, 255),
	// reserve extra space in savegame here. (currently 7 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U8 | SLE_VAR_NULL, 7, 2, 255),

	SLE_END()
};

static const SaveLoad _roadveh_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Road, 1), // Road type. VEH_Road in mem, 1 in file.
	SLE_INCLUDEX(0, INC_VEHICLE_COMMON),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,state),					SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,frame),					SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,unk2),					SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,overtaking),		SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,overtaking_ctr),SLE_UINT8),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,crashed_ctr),		SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,reverse_ctr),			SLE_UINT8),

	SLE_CONDREFX(offsetof(Vehicle,u)+offsetof(VehicleRoad,slot), REF_ROADSTOPS, 6, 255),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,slotindex), SLE_UINT8, 6, 255),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleRoad,slot_age), SLE_UINT8, 6, 255),
	// reserve extra space in savegame here. (currently 16 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U64 | SLE_VAR_NULL, 2, 2, 255),

	SLE_END()
};

static const SaveLoad _ship_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Ship, 2), // Ship type. VEH_Ship in mem, 2 in file.
	SLE_INCLUDEX(0, INC_VEHICLE_COMMON),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleShip,state),				SLE_UINT8),

	// reserve extra space in savegame here. (currently 16 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U64 | SLE_VAR_NULL, 2, 2, 255),

	SLE_END()
};

static const SaveLoad _aircraft_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Aircraft, 3), // Aircraft type. VEH_Aircraft in mem, 3 in file.
	SLE_INCLUDEX(0, INC_VEHICLE_COMMON),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleAir,crashed_counter),	SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleAir,pos),							SLE_UINT8),

	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleAir,targetairport),		SLE_FILE_U8 | SLE_VAR_U16, 0, 4),
	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleAir,targetairport),		SLE_UINT16, 5, 255),

	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleAir,state),						SLE_UINT8),

	SLE_CONDVARX(offsetof(Vehicle,u)+offsetof(VehicleAir,previous_pos),			SLE_UINT8, 2, 255),

	// reserve extra space in savegame here. (currently 15 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U8 | SLE_VAR_NULL, 15, 2, 255),

	SLE_END()
};

static const SaveLoad _special_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Special, 4),

	SLE_VAR(Vehicle,subtype,					SLE_UINT8),

	SLE_CONDVAR(Vehicle,tile,					SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,tile,					SLE_UINT32, 6, 255),

	SLE_CONDVAR(Vehicle,x_pos,				SLE_FILE_I16 | SLE_VAR_I32, 0, 5),
	SLE_CONDVAR(Vehicle,x_pos,				SLE_INT32, 6, 255),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_FILE_I16 | SLE_VAR_I32, 0, 5),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_INT32, 6, 255),
	SLE_VAR(Vehicle,z_pos,						SLE_UINT8),

	SLE_VAR(Vehicle,cur_image,				SLE_UINT16),
	SLE_VAR(Vehicle,sprite_width,			SLE_UINT8),
	SLE_VAR(Vehicle,sprite_height,		SLE_UINT8),
	SLE_VAR(Vehicle,z_height,					SLE_UINT8),
	SLE_VAR(Vehicle,x_offs,						SLE_INT8),
	SLE_VAR(Vehicle,y_offs,						SLE_INT8),
	SLE_VAR(Vehicle,progress,					SLE_UINT8),
	SLE_VAR(Vehicle,vehstatus,				SLE_UINT8),

	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleSpecial,unk0),	SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleSpecial,unk2),	SLE_UINT8),

	// reserve extra space in savegame here. (currently 16 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U64 | SLE_VAR_NULL, 2, 2, 255),

	SLE_END()
};

static const SaveLoad _disaster_desc[] = {
	SLE_WRITEBYTE(Vehicle,type,VEH_Disaster, 5),

	SLE_REF(Vehicle,next,							REF_VEHICLE_OLD),

	SLE_VAR(Vehicle,subtype,					SLE_UINT8),
	SLE_CONDVAR(Vehicle,tile,					SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,tile,					SLE_UINT32, 6, 255),
	SLE_CONDVAR(Vehicle,dest_tile,		SLE_FILE_U16 | SLE_VAR_U32, 0, 5),
	SLE_CONDVAR(Vehicle,dest_tile,		SLE_UINT32, 6, 255),

	SLE_CONDVAR(Vehicle,x_pos,				SLE_FILE_I16 | SLE_VAR_I32, 0, 5),
	SLE_CONDVAR(Vehicle,x_pos,				SLE_INT32, 6, 255),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_FILE_I16 | SLE_VAR_I32, 0, 5),
	SLE_CONDVAR(Vehicle,y_pos,				SLE_INT32, 6, 255),
	SLE_VAR(Vehicle,z_pos,						SLE_UINT8),
	SLE_VAR(Vehicle,direction,				SLE_UINT8),

	SLE_VAR(Vehicle,x_offs,						SLE_INT8),
	SLE_VAR(Vehicle,y_offs,						SLE_INT8),
	SLE_VAR(Vehicle,sprite_width,			SLE_UINT8),
	SLE_VAR(Vehicle,sprite_height,		SLE_UINT8),
	SLE_VAR(Vehicle,z_height,					SLE_UINT8),
	SLE_VAR(Vehicle,owner,						SLE_UINT8),
	SLE_VAR(Vehicle,vehstatus,				SLE_UINT8),
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, station), SLE_FILE_U8 | SLE_VAR_U16, 0, 4),
	SLE_CONDVARX(offsetof(Vehicle, current_order) + offsetof(Order, station), SLE_UINT16, 5, 255),

	SLE_VAR(Vehicle,cur_image,				SLE_UINT16),
	SLE_VAR(Vehicle,age,							SLE_UINT16),

	SLE_VAR(Vehicle,tick_counter,			SLE_UINT8),

	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleDisaster,image_override),	SLE_UINT16),
	SLE_VARX(offsetof(Vehicle,u)+offsetof(VehicleDisaster,unk2),						SLE_UINT16),

	// reserve extra space in savegame here. (currently 16 bytes)
	SLE_CONDARR(NullStruct,null,SLE_FILE_U64 | SLE_VAR_NULL, 2, 2, 255),

	SLE_END()
};


static const void *_veh_descs[] = {
	_train_desc,
	_roadveh_desc,
	_ship_desc,
	_aircraft_desc,
	_special_desc,
	_disaster_desc,
};

// Will be called when the vehicles need to be saved.
static void Save_VEHS(void)
{
	Vehicle *v;
	// Write the vehicles
	FOR_ALL_VEHICLES(v) {
		if (v->type != 0) {
			SlSetArrayIndex(v->index);
			SlObject(v, _veh_descs[v->type - 0x10]);
		}
	}
}

// Will be called when vehicles need to be loaded.
static void Load_VEHS(void)
{
	int index;
	Vehicle *v;

	while ((index = SlIterateArray()) != -1) {
		Vehicle *v;

		if (!AddBlockIfNeeded(&_vehicle_pool, index))
			error("Vehicles: failed loading savegame: too many vehicles");

		v = GetVehicle(index);
		SlObject(v, _veh_descs[SlReadByte()]);

		/* Old savegames used 'last_station_visited = 0xFF' */
		if (_sl_version < 5 && v->last_station_visited == 0xFF)
			v->last_station_visited = INVALID_STATION;

		if (_sl_version < 5) {
			/* Convert the current_order.type (which is a mix of type and flags, because
			    in those versions, they both were 4 bits big) to type and flags */
			v->current_order.flags = (v->current_order.type & 0xF0) >> 4;
			v->current_order.type  =  v->current_order.type & 0x0F;
		}
	}

	/* Check for shared order-lists (we now use pointers for that) */
	if (_sl_full_version < 0x502) {
		FOR_ALL_VEHICLES(v) {
			Vehicle *u;

			if (v->type == 0)
				continue;

			FOR_ALL_VEHICLES_FROM(u, v->index + 1) {
				if (u->type == 0)
					continue;

				/* If a vehicle has the same orders, add the link to eachother
				    in both vehicles */
				if (v->orders == u->orders) {
					v->next_shared = u;
					u->prev_shared = v;
					break;
				}
			}
		}
	}
}

const ChunkHandler _veh_chunk_handlers[] = {
	{ 'VEHS', Save_VEHS, Load_VEHS, CH_SPARSE_ARRAY | CH_LAST},
};