/* $Id$ */
/*
* 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 .
*/
/** @file ship_cmd.cpp Handling of ships. */
#include "stdafx.h"
#include "ship.h"
#include "landscape.h"
#include "timetable.h"
#include "news_func.h"
#include "company_func.h"
#include "pathfinder/npf/npf_func.h"
#include "depot_base.h"
#include "station_base.h"
#include "newgrf_engine.h"
#include "pathfinder/yapf/yapf.h"
#include "newgrf_sound.h"
#include "spritecache.h"
#include "strings_func.h"
#include "window_func.h"
#include "date_func.h"
#include "vehicle_func.h"
#include "sound_func.h"
#include "ai/ai.hpp"
#include "game/game.hpp"
#include "pathfinder/opf/opf_ship.h"
#include "engine_base.h"
#include "company_base.h"
#include "tunnelbridge_map.h"
#include "zoom_func.h"
#include "framerate_type.h"
#include "table/strings.h"
#include "safeguards.h"
/**
* Determine the effective #WaterClass for a ship travelling on a tile.
* @param tile Tile of interest
* @return the waterclass to be used by the ship.
*/
WaterClass GetEffectiveWaterClass(TileIndex tile)
{
if (HasTileWaterClass(tile)) return GetWaterClass(tile);
if (IsTileType(tile, MP_TUNNELBRIDGE)) {
assert(GetTunnelBridgeTransportType(tile) == TRANSPORT_WATER);
return WATER_CLASS_CANAL;
}
if (IsTileType(tile, MP_RAILWAY)) {
assert(GetRailGroundType(tile) == RAIL_GROUND_WATER);
return WATER_CLASS_SEA;
}
NOT_REACHED();
}
static const uint16 _ship_sprites[] = {0x0E5D, 0x0E55, 0x0E65, 0x0E6D};
template <>
bool IsValidImageIndex(uint8 image_index)
{
return image_index < lengthof(_ship_sprites);
}
static inline TrackBits GetTileShipTrackStatus(TileIndex tile)
{
return TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_WATER, 0));
}
static void GetShipIcon(EngineID engine, EngineImageType image_type, VehicleSpriteSeq *result)
{
const Engine *e = Engine::Get(engine);
uint8 spritenum = e->u.ship.image_index;
if (is_custom_sprite(spritenum)) {
GetCustomVehicleIcon(engine, DIR_W, image_type, result);
if (result->IsValid()) return;
spritenum = e->original_image_index;
}
assert(IsValidImageIndex(spritenum));
result->Set(DIR_W + _ship_sprites[spritenum]);
}
void DrawShipEngine(int left, int right, int preferred_x, int y, EngineID engine, PaletteID pal, EngineImageType image_type)
{
VehicleSpriteSeq seq;
GetShipIcon(engine, image_type, &seq);
Rect rect;
seq.GetBounds(&rect);
preferred_x = Clamp(preferred_x,
left - UnScaleGUI(rect.left),
right - UnScaleGUI(rect.right));
seq.Draw(preferred_x, y, pal, pal == PALETTE_CRASH);
}
/**
* Get the size of the sprite of a ship sprite heading west (used for lists).
* @param engine The engine to get the sprite from.
* @param[out] width The width of the sprite.
* @param[out] height The height of the sprite.
* @param[out] xoffs Number of pixels to shift the sprite to the right.
* @param[out] yoffs Number of pixels to shift the sprite downwards.
* @param image_type Context the sprite is used in.
*/
void GetShipSpriteSize(EngineID engine, uint &width, uint &height, int &xoffs, int &yoffs, EngineImageType image_type)
{
VehicleSpriteSeq seq;
GetShipIcon(engine, image_type, &seq);
Rect rect;
seq.GetBounds(&rect);
width = UnScaleGUI(rect.right - rect.left + 1);
height = UnScaleGUI(rect.bottom - rect.top + 1);
xoffs = UnScaleGUI(rect.left);
yoffs = UnScaleGUI(rect.top);
}
void Ship::GetImage(Direction direction, EngineImageType image_type, VehicleSpriteSeq *result) const
{
uint8 spritenum = this->spritenum;
if (is_custom_sprite(spritenum)) {
GetCustomVehicleSprite(this, direction, image_type, result);
if (result->IsValid()) return;
spritenum = this->GetEngine()->original_image_index;
}
assert(IsValidImageIndex(spritenum));
result->Set(_ship_sprites[spritenum] + direction);
}
static const Depot *FindClosestShipDepot(const Vehicle *v, uint max_distance)
{
/* Find the closest depot */
const Depot *depot;
const Depot *best_depot = NULL;
/* If we don't have a maximum distance, i.e. distance = 0,
* we want to find any depot so the best distance of no
* depot must be more than any correct distance. On the
* other hand if we have set a maximum distance, any depot
* further away than max_distance can safely be ignored. */
uint best_dist = max_distance == 0 ? UINT_MAX : max_distance + 1;
FOR_ALL_DEPOTS(depot) {
TileIndex tile = depot->xy;
if (IsShipDepotTile(tile) && IsTileOwner(tile, v->owner)) {
uint dist = DistanceManhattan(tile, v->tile);
if (dist < best_dist) {
best_dist = dist;
best_depot = depot;
}
}
}
return best_depot;
}
static void CheckIfShipNeedsService(Vehicle *v)
{
if (Company::Get(v->owner)->settings.vehicle.servint_ships == 0 || !v->NeedsAutomaticServicing()) return;
if (v->IsChainInDepot()) {
VehicleServiceInDepot(v);
return;
}
uint max_distance;
switch (_settings_game.pf.pathfinder_for_ships) {
case VPF_OPF: max_distance = 12; break;
case VPF_NPF: max_distance = _settings_game.pf.npf.maximum_go_to_depot_penalty / NPF_TILE_LENGTH; break;
case VPF_YAPF: max_distance = _settings_game.pf.yapf.maximum_go_to_depot_penalty / YAPF_TILE_LENGTH; break;
default: NOT_REACHED();
}
const Depot *depot = FindClosestShipDepot(v, max_distance);
if (depot == NULL) {
if (v->current_order.IsType(OT_GOTO_DEPOT)) {
v->current_order.MakeDummy();
SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
}
return;
}
v->current_order.MakeGoToDepot(depot->index, ODTFB_SERVICE);
v->dest_tile = depot->xy;
SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
}
/**
* Update the caches of this ship.
*/
void Ship::UpdateCache()
{
const ShipVehicleInfo *svi = ShipVehInfo(this->engine_type);
/* Get speed fraction for the current water type. Aqueducts are always canals. */
bool is_ocean = GetEffectiveWaterClass(this->tile) == WATER_CLASS_SEA;
uint raw_speed = GetVehicleProperty(this, PROP_SHIP_SPEED, svi->max_speed);
this->vcache.cached_max_speed = svi->ApplyWaterClassSpeedFrac(raw_speed, is_ocean);
/* Update cargo aging period. */
this->vcache.cached_cargo_age_period = GetVehicleProperty(this, PROP_SHIP_CARGO_AGE_PERIOD, EngInfo(this->engine_type)->cargo_age_period);
this->UpdateVisualEffect();
}
Money Ship::GetRunningCost() const
{
const Engine *e = this->GetEngine();
uint cost_factor = GetVehicleProperty(this, PROP_SHIP_RUNNING_COST_FACTOR, e->u.ship.running_cost);
return GetPrice(PR_RUNNING_SHIP, cost_factor, e->GetGRF());
}
void Ship::OnNewDay()
{
if ((++this->day_counter & 7) == 0) {
DecreaseVehicleValue(this);
}
CheckVehicleBreakdown(this);
AgeVehicle(this);
CheckIfShipNeedsService(this);
CheckOrders(this);
if (this->running_ticks == 0) return;
CommandCost cost(EXPENSES_SHIP_RUN, this->GetRunningCost() * this->running_ticks / (DAYS_IN_YEAR * DAY_TICKS));
this->profit_this_year -= cost.GetCost();
this->running_ticks = 0;
SubtractMoneyFromCompanyFract(this->owner, cost);
SetWindowDirty(WC_VEHICLE_DETAILS, this->index);
/* we need this for the profit */
SetWindowClassesDirty(WC_SHIPS_LIST);
}
Trackdir Ship::GetVehicleTrackdir() const
{
if (this->vehstatus & VS_CRASHED) return INVALID_TRACKDIR;
if (this->IsInDepot()) {
/* We'll assume the ship is facing outwards */
return DiagDirToDiagTrackdir(GetShipDepotDirection(this->tile));
}
if (this->state == TRACK_BIT_WORMHOLE) {
/* ship on aqueduct, so just use his direction and assume a diagonal track */
return DiagDirToDiagTrackdir(DirToDiagDir(this->direction));
}
return TrackDirectionToTrackdir(FindFirstTrack(this->state), this->direction);
}
void Ship::MarkDirty()
{
this->colourmap = PAL_NONE;
this->UpdateViewport(true, false);
this->UpdateCache();
}
static void PlayShipSound(const Vehicle *v)
{
if (!PlayVehicleSound(v, VSE_START)) {
SndPlayVehicleFx(ShipVehInfo(v->engine_type)->sfx, v);
}
}
void Ship::PlayLeaveStationSound() const
{
PlayShipSound(this);
}
TileIndex Ship::GetOrderStationLocation(StationID station)
{
if (station == this->last_station_visited) this->last_station_visited = INVALID_STATION;
const Station *st = Station::Get(station);
if (st->dock_tile != INVALID_TILE) {
return TILE_ADD(st->dock_tile, ToTileIndexDiff(GetDockOffset(st->dock_tile)));
} else {
this->IncrementRealOrderIndex();
return 0;
}
}
void Ship::UpdateDeltaXY()
{
static const int8 _delta_xy_table[8][4] = {
/* y_extent, x_extent, y_offs, x_offs */
{ 6, 6, -3, -3}, // N
{ 6, 32, -3, -16}, // NE
{ 6, 6, -3, -3}, // E
{32, 6, -16, -3}, // SE
{ 6, 6, -3, -3}, // S
{ 6, 32, -3, -16}, // SW
{ 6, 6, -3, -3}, // W
{32, 6, -16, -3}, // NW
};
const int8 *bb = _delta_xy_table[this->direction];
this->x_offs = bb[3];
this->y_offs = bb[2];
this->x_extent = bb[1];
this->y_extent = bb[0];
this->z_extent = 6;
}
static bool CheckShipLeaveDepot(Ship *v)
{
if (!v->IsChainInDepot()) return false;
/* We are leaving a depot, but have to go to the exact same one; re-enter */
if (v->current_order.IsType(OT_GOTO_DEPOT) &&
IsShipDepotTile(v->tile) && GetDepotIndex(v->tile) == v->current_order.GetDestination()) {
VehicleEnterDepot(v);
return true;
}
TileIndex tile = v->tile;
Axis axis = GetShipDepotAxis(tile);
DiagDirection north_dir = ReverseDiagDir(AxisToDiagDir(axis));
TileIndex north_neighbour = TILE_ADD(tile, TileOffsByDiagDir(north_dir));
DiagDirection south_dir = AxisToDiagDir(axis);
TileIndex south_neighbour = TILE_ADD(tile, 2 * TileOffsByDiagDir(south_dir));
TrackBits north_tracks = DiagdirReachesTracks(north_dir) & GetTileShipTrackStatus(north_neighbour);
TrackBits south_tracks = DiagdirReachesTracks(south_dir) & GetTileShipTrackStatus(south_neighbour);
if (north_tracks && south_tracks) {
/* Ask pathfinder for best direction */
bool reverse = false;
bool path_found;
switch (_settings_game.pf.pathfinder_for_ships) {
case VPF_OPF: reverse = OPFShipChooseTrack(v, north_neighbour, north_dir, north_tracks, path_found) == INVALID_TRACK; break; // OPF always allows reversing
case VPF_NPF: reverse = NPFShipCheckReverse(v); break;
case VPF_YAPF: reverse = YapfShipCheckReverse(v); break;
default: NOT_REACHED();
}
if (reverse) north_tracks = TRACK_BIT_NONE;
}
if (north_tracks) {
/* Leave towards north */
v->direction = DiagDirToDir(north_dir);
} else if (south_tracks) {
/* Leave towards south */
v->direction = DiagDirToDir(south_dir);
} else {
/* Both ways blocked */
return false;
}
v->state = AxisToTrackBits(axis);
v->vehstatus &= ~VS_HIDDEN;
v->cur_speed = 0;
v->UpdateViewport(true, true);
SetWindowDirty(WC_VEHICLE_DEPOT, v->tile);
PlayShipSound(v);
VehicleServiceInDepot(v);
InvalidateWindowData(WC_VEHICLE_DEPOT, v->tile);
SetWindowClassesDirty(WC_SHIPS_LIST);
return false;
}
static bool ShipAccelerate(Vehicle *v)
{
uint spd;
byte t;
spd = min(v->cur_speed + 1, v->vcache.cached_max_speed);
spd = min(spd, v->current_order.GetMaxSpeed() * 2);
/* updates statusbar only if speed have changed to save CPU time */
if (spd != v->cur_speed) {
v->cur_speed = spd;
SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
}
/* Convert direction-independent speed into direction-dependent speed. (old movement method) */
spd = v->GetOldAdvanceSpeed(spd);
if (spd == 0) return false;
if ((byte)++spd == 0) return true;
v->progress = (t = v->progress) - (byte)spd;
return (t < v->progress);
}
/**
* Ship arrives at a dock. If it is the first time, send out a news item.
* @param v Ship that arrived.
* @param st Station being visited.
*/
static void ShipArrivesAt(const Vehicle *v, Station *st)
{
/* Check if station was ever visited before */
if (!(st->had_vehicle_of_type & HVOT_SHIP)) {
st->had_vehicle_of_type |= HVOT_SHIP;
SetDParam(0, st->index);
AddVehicleNewsItem(
STR_NEWS_FIRST_SHIP_ARRIVAL,
(v->owner == _local_company) ? NT_ARRIVAL_COMPANY : NT_ARRIVAL_OTHER,
v->index,
st->index
);
AI::NewEvent(v->owner, new ScriptEventStationFirstVehicle(st->index, v->index));
Game::NewEvent(new ScriptEventStationFirstVehicle(st->index, v->index));
}
}
/**
* Runs the pathfinder to choose a track to continue along.
*
* @param v Ship to navigate
* @param tile Tile, the ship is about to enter
* @param enterdir Direction of entering
* @param tracks Available track choices on \a tile
* @return Track to choose, or INVALID_TRACK when to reverse.
*/
static Track ChooseShipTrack(Ship *v, TileIndex tile, DiagDirection enterdir, TrackBits tracks)
{
assert(IsValidDiagDirection(enterdir));
bool path_found = true;
Track track;
switch (_settings_game.pf.pathfinder_for_ships) {
case VPF_OPF: track = OPFShipChooseTrack(v, tile, enterdir, tracks, path_found); break;
case VPF_NPF: track = NPFShipChooseTrack(v, tile, enterdir, tracks, path_found); break;
case VPF_YAPF: track = YapfShipChooseTrack(v, tile, enterdir, tracks, path_found); break;
default: NOT_REACHED();
}
v->HandlePathfindingResult(path_found);
return track;
}
static inline TrackBits GetAvailShipTracks(TileIndex tile, DiagDirection dir)
{
return GetTileShipTrackStatus(tile) & DiagdirReachesTracks(dir);
}
static const byte _ship_subcoord[4][6][3] = {
{
{15, 8, 1},
{ 0, 0, 0},
{ 0, 0, 0},
{15, 8, 2},
{15, 7, 0},
{ 0, 0, 0},
},
{
{ 0, 0, 0},
{ 8, 0, 3},
{ 7, 0, 2},
{ 0, 0, 0},
{ 8, 0, 4},
{ 0, 0, 0},
},
{
{ 0, 8, 5},
{ 0, 0, 0},
{ 0, 7, 6},
{ 0, 0, 0},
{ 0, 0, 0},
{ 0, 8, 4},
},
{
{ 0, 0, 0},
{ 8, 15, 7},
{ 0, 0, 0},
{ 8, 15, 6},
{ 0, 0, 0},
{ 7, 15, 0},
}
};
static void ShipController(Ship *v)
{
uint32 r;
const byte *b;
Direction dir;
Track track;
TrackBits tracks;
v->tick_counter++;
v->current_order_time++;
if (v->HandleBreakdown()) return;
if (v->vehstatus & VS_STOPPED) return;
ProcessOrders(v);
v->HandleLoading();
if (v->current_order.IsType(OT_LOADING)) return;
if (CheckShipLeaveDepot(v)) return;
v->ShowVisualEffect();
if (!ShipAccelerate(v)) return;
GetNewVehiclePosResult gp = GetNewVehiclePos(v);
if (v->state != TRACK_BIT_WORMHOLE) {
/* Not on a bridge */
if (gp.old_tile == gp.new_tile) {
/* Staying in tile */
if (v->IsInDepot()) {
gp.x = v->x_pos;
gp.y = v->y_pos;
} else {
/* Not inside depot */
r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
if (HasBit(r, VETS_CANNOT_ENTER)) goto reverse_direction;
/* A leave station order only needs one tick to get processed, so we can
* always skip ahead. */
if (v->current_order.IsType(OT_LEAVESTATION)) {
v->current_order.Free();
SetWindowWidgetDirty(WC_VEHICLE_VIEW, v->index, WID_VV_START_STOP);
/* Test if continuing forward would lead to a dead-end, moving into the dock. */
DiagDirection exitdir = VehicleExitDir(v->direction, v->state);
TileIndex tile = TileAddByDiagDir(v->tile, exitdir);
if (TrackStatusToTrackBits(GetTileTrackStatus(tile, TRANSPORT_WATER, 0, exitdir)) == TRACK_BIT_NONE) goto reverse_direction;
} else if (v->dest_tile != 0) {
/* We have a target, let's see if we reached it... */
if (v->current_order.IsType(OT_GOTO_WAYPOINT) &&
DistanceManhattan(v->dest_tile, gp.new_tile) <= 3) {
/* We got within 3 tiles of our target buoy, so let's skip to our
* next order */
UpdateVehicleTimetable(v, true);
v->IncrementRealOrderIndex();
v->current_order.MakeDummy();
} else {
/* Non-buoy orders really need to reach the tile */
if (v->dest_tile == gp.new_tile) {
if (v->current_order.IsType(OT_GOTO_DEPOT)) {
if ((gp.x & 0xF) == 8 && (gp.y & 0xF) == 8) {
VehicleEnterDepot(v);
return;
}
} else if (v->current_order.IsType(OT_GOTO_STATION)) {
v->last_station_visited = v->current_order.GetDestination();
/* Process station in the orderlist. */
Station *st = Station::Get(v->current_order.GetDestination());
if (st->facilities & FACIL_DOCK) { // ugly, ugly workaround for problem with ships able to drop off cargo at wrong stations
ShipArrivesAt(v, st);
v->BeginLoading();
} else { // leave stations without docks right aways
v->current_order.MakeLeaveStation();
v->IncrementRealOrderIndex();
}
}
}
}
}
}
} else {
/* New tile */
if (!IsValidTile(gp.new_tile)) goto reverse_direction;
DiagDirection diagdir = DiagdirBetweenTiles(gp.old_tile, gp.new_tile);
assert(diagdir != INVALID_DIAGDIR);
tracks = GetAvailShipTracks(gp.new_tile, diagdir);
if (tracks == TRACK_BIT_NONE) goto reverse_direction;
/* Choose a direction, and continue if we find one */
track = ChooseShipTrack(v, gp.new_tile, diagdir, tracks);
if (track == INVALID_TRACK) goto reverse_direction;
b = _ship_subcoord[diagdir][track];
gp.x = (gp.x & ~0xF) | b[0];
gp.y = (gp.y & ~0xF) | b[1];
/* Call the landscape function and tell it that the vehicle entered the tile */
r = VehicleEnterTile(v, gp.new_tile, gp.x, gp.y);
if (HasBit(r, VETS_CANNOT_ENTER)) goto reverse_direction;
if (!HasBit(r, VETS_ENTERED_WORMHOLE)) {
v->tile = gp.new_tile;
v->state = TrackToTrackBits(track);
/* Update ship cache when the water class changes. Aqueducts are always canals. */
WaterClass old_wc = GetEffectiveWaterClass(gp.old_tile);
WaterClass new_wc = GetEffectiveWaterClass(gp.new_tile);
if (old_wc != new_wc) v->UpdateCache();
}
v->direction = (Direction)b[2];
}
} else {
/* On a bridge */
if (!IsTileType(gp.new_tile, MP_TUNNELBRIDGE) || !HasBit(VehicleEnterTile(v, gp.new_tile, gp.x, gp.y), VETS_ENTERED_WORMHOLE)) {
v->x_pos = gp.x;
v->y_pos = gp.y;
v->UpdatePosition();
if ((v->vehstatus & VS_HIDDEN) == 0) v->Vehicle::UpdateViewport(true);
return;
}
}
/* update image of ship, as well as delta XY */
v->x_pos = gp.x;
v->y_pos = gp.y;
v->z_pos = GetSlopePixelZ(gp.x, gp.y);
getout:
v->UpdatePosition();
v->UpdateViewport(true, true);
return;
reverse_direction:
dir = ReverseDir(v->direction);
v->direction = dir;
goto getout;
}
bool Ship::Tick()
{
PerformanceAccumulator framerate(PFE_GL_SHIPS);
if (!(this->vehstatus & VS_STOPPED)) this->running_ticks++;
ShipController(this);
return true;
}
/**
* Build a ship.
* @param tile tile of the depot where ship is built.
* @param flags type of operation.
* @param e the engine to build.
* @param data unused.
* @param[out] ret the vehicle that has been built.
* @return the cost of this operation or an error.
*/
CommandCost CmdBuildShip(TileIndex tile, DoCommandFlag flags, const Engine *e, uint16 data, Vehicle **ret)
{
tile = GetShipDepotNorthTile(tile);
if (flags & DC_EXEC) {
int x;
int y;
const ShipVehicleInfo *svi = &e->u.ship;
Ship *v = new Ship();
*ret = v;
v->owner = _current_company;
v->tile = tile;
x = TileX(tile) * TILE_SIZE + TILE_SIZE / 2;
y = TileY(tile) * TILE_SIZE + TILE_SIZE / 2;
v->x_pos = x;
v->y_pos = y;
v->z_pos = GetSlopePixelZ(x, y);
v->UpdateDeltaXY();
v->vehstatus = VS_HIDDEN | VS_STOPPED | VS_DEFPAL;
v->spritenum = svi->image_index;
v->cargo_type = e->GetDefaultCargoType();
v->cargo_cap = svi->capacity;
v->refit_cap = 0;
v->last_station_visited = INVALID_STATION;
v->last_loading_station = INVALID_STATION;
v->engine_type = e->index;
v->reliability = e->reliability;
v->reliability_spd_dec = e->reliability_spd_dec;
v->max_age = e->GetLifeLengthInDays();
_new_vehicle_id = v->index;
v->state = TRACK_BIT_DEPOT;
v->SetServiceInterval(Company::Get(_current_company)->settings.vehicle.servint_ships);
v->date_of_last_service = _date;
v->build_year = _cur_year;
v->sprite_seq.Set(SPR_IMG_QUERY);
v->random_bits = VehicleRandomBits();
v->UpdateCache();
if (e->flags & ENGINE_EXCLUSIVE_PREVIEW) SetBit(v->vehicle_flags, VF_BUILT_AS_PROTOTYPE);
v->SetServiceIntervalIsPercent(Company::Get(_current_company)->settings.vehicle.servint_ispercent);
v->InvalidateNewGRFCacheOfChain();
v->cargo_cap = e->DetermineCapacity(v);
v->InvalidateNewGRFCacheOfChain();
v->UpdatePosition();
}
return CommandCost();
}
bool Ship::FindClosestDepot(TileIndex *location, DestinationID *destination, bool *reverse)
{
const Depot *depot = FindClosestShipDepot(this, 0);
if (depot == NULL) return false;
if (location != NULL) *location = depot->xy;
if (destination != NULL) *destination = depot->index;
return true;
}