OpenTTD Source  1.11.0-beta2
newgrf_airport.cpp
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1 /*
2  * This file is part of OpenTTD.
3  * 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.
4  * 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.
5  * 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/>.
6  */
7 
10 #include "stdafx.h"
11 #include "debug.h"
12 #include "date_func.h"
13 #include "newgrf_spritegroup.h"
14 #include "newgrf_text.h"
15 #include "station_base.h"
16 #include "newgrf_class_func.h"
17 
18 #include "safeguards.h"
19 
22  struct Station *st;
23  byte airport_id;
24  byte layout;
26 
37  {
38  }
39 
40  uint32 GetRandomBits() const override;
41  uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override;
42  void StorePSA(uint pos, int32 value) override;
43 };
44 
47  AirportScopeResolver airport_scope;
48 
49  AirportResolverObject(TileIndex tile, Station *st, byte airport_id, byte layout,
51 
52  ScopeResolver *GetScope(VarSpriteGroupScope scope = VSG_SCOPE_SELF, byte relative = 0) override
53  {
54  switch (scope) {
55  case VSG_SCOPE_SELF: return &this->airport_scope;
56  default: return ResolverObject::GetScope(scope, relative);
57  }
58  }
59 
60  const SpriteGroup *ResolveReal(const RealSpriteGroup *group) const override;
61 
62  GrfSpecFeature GetFeature() const override;
63  uint32 GetDebugID() const override;
64 };
65 
71 template <typename Tspec, typename Tid, Tid Tmax>
73 {
74  AirportClass::Get(AirportClass::Allocate('SMAL'))->name = STR_AIRPORT_CLASS_SMALL;
75  AirportClass::Get(AirportClass::Allocate('LARG'))->name = STR_AIRPORT_CLASS_LARGE;
76  AirportClass::Get(AirportClass::Allocate('HUB_'))->name = STR_AIRPORT_CLASS_HUB;
77  AirportClass::Get(AirportClass::Allocate('HELI'))->name = STR_AIRPORT_CLASS_HELIPORTS;
78 }
79 
80 template <typename Tspec, typename Tid, Tid Tmax>
82 {
83  return true;
84 }
85 
87 
88 
90 
92 
99 /* static */ const AirportSpec *AirportSpec::Get(byte type)
100 {
101  assert(type < lengthof(AirportSpec::specs));
102  const AirportSpec *as = &AirportSpec::specs[type];
103  if (type >= NEW_AIRPORT_OFFSET && !as->enabled) {
104  if (_airport_mngr.GetGRFID(type) == 0) return as;
105  byte subst_id = _airport_mngr.GetSubstituteID(type);
106  if (subst_id == AT_INVALID) return as;
107  as = &AirportSpec::specs[subst_id];
108  }
110  return as;
111 }
112 
120 {
121  assert(type < lengthof(AirportSpec::specs));
122  return &AirportSpec::specs[type];
123 }
124 
127 {
128  if (!this->enabled) return false;
129  if (_cur_year < this->min_year) return false;
131  return _cur_year <= this->max_year;
132 }
133 
140 bool AirportSpec::IsWithinMapBounds(byte table, TileIndex tile) const
141 {
142  if (table >= this->num_table) return false;
143 
144  byte w = this->size_x;
145  byte h = this->size_y;
146  if (this->rotation[table] == DIR_E || this->rotation[table] == DIR_W) Swap(w, h);
147 
148  return TileX(tile) + w < MapSizeX() &&
149  TileY(tile) + h < MapSizeY();
150 }
151 
156 {
157  extern const AirportSpec _origin_airport_specs[];
158  memset(&AirportSpec::specs, 0, sizeof(AirportSpec::specs));
159  memcpy(&AirportSpec::specs, &_origin_airport_specs, sizeof(AirportSpec) * NEW_AIRPORT_OFFSET);
160 
161  _airport_mngr.ResetOverride();
162 }
163 
168 {
169  for (int i = 0; i < NUM_AIRPORTS; i++) {
171  if (as->enabled) AirportClass::Assign(as);
172  }
173 }
174 
175 
176 void AirportOverrideManager::SetEntitySpec(AirportSpec *as)
177 {
178  byte airport_id = this->AddEntityID(as->grf_prop.local_id, as->grf_prop.grffile->grfid, as->grf_prop.subst_id);
179 
180  if (airport_id == invalid_ID) {
181  grfmsg(1, "Airport.SetEntitySpec: Too many airports allocated. Ignoring.");
182  return;
183  }
184 
185  memcpy(AirportSpec::GetWithoutOverride(airport_id), as, sizeof(*as));
186 
187  /* Now add the overrides. */
188  for (int i = 0; i < max_offset; i++) {
189  AirportSpec *overridden_as = AirportSpec::GetWithoutOverride(i);
190 
191  if (entity_overrides[i] != as->grf_prop.local_id || grfid_overrides[i] != as->grf_prop.grffile->grfid) continue;
192 
193  overridden_as->grf_prop.override = airport_id;
194  overridden_as->enabled = false;
195  entity_overrides[i] = invalid_ID;
196  grfid_overrides[i] = 0;
197  }
198 }
199 
200 /* virtual */ uint32 AirportScopeResolver::GetVariable(byte variable, uint32 parameter, bool *available) const
201 {
202  switch (variable) {
203  case 0x40: return this->layout;
204  }
205 
206  if (this->st == nullptr) {
207  *available = false;
208  return UINT_MAX;
209  }
210 
211  switch (variable) {
212  /* Get a variable from the persistent storage */
213  case 0x7C: return (this->st->airport.psa != nullptr) ? this->st->airport.psa->GetValue(parameter) : 0;
214 
215  case 0xF0: return this->st->facilities;
216  case 0xFA: return Clamp(this->st->build_date - DAYS_TILL_ORIGINAL_BASE_YEAR, 0, 65535);
217  }
218 
219  return this->st->GetNewGRFVariable(this->ro, variable, parameter, available);
220 }
221 
222 /* virtual */ const SpriteGroup *AirportResolverObject::ResolveReal(const RealSpriteGroup *group) const
223 {
224  /* Airport action 2s should always have only 1 "loaded" state, but some
225  * times things don't follow the spec... */
226  if (group->num_loaded > 0) return group->loaded[0];
227  if (group->num_loading > 0) return group->loading[0];
228 
229  return nullptr;
230 }
231 
233 {
234  return GSF_AIRPORTS;
235 }
236 
238 {
239  return AirportSpec::Get(this->airport_scope.airport_id)->grf_prop.local_id;
240 }
241 
242 /* virtual */ uint32 AirportScopeResolver::GetRandomBits() const
243 {
244  return this->st == nullptr ? 0 : this->st->random_bits;
245 }
246 
252 /* virtual */ void AirportScopeResolver::StorePSA(uint pos, int32 value)
253 {
254  if (this->st == nullptr) return;
255 
256  if (this->st->airport.psa == nullptr) {
257  /* There is no need to create a storage if the value is zero. */
258  if (value == 0) return;
259 
260  /* Create storage on first modification. */
261  uint32 grfid = (this->ro.grffile != nullptr) ? this->ro.grffile->grfid : 0;
263  this->st->airport.psa = new PersistentStorage(grfid, GSF_AIRPORTS, this->st->airport.tile);
264  }
265  this->st->airport.psa->StoreValue(pos, value);
266 }
267 
278 AirportResolverObject::AirportResolverObject(TileIndex tile, Station *st, byte airport_id, byte layout,
279  CallbackID callback, uint32 param1, uint32 param2)
280  : ResolverObject(AirportSpec::Get(airport_id)->grf_prop.grffile, callback, param1, param2), airport_scope(*this, tile, st, airport_id, layout)
281 {
282  this->root_spritegroup = AirportSpec::Get(airport_id)->grf_prop.spritegroup[0];
283 }
284 
285 SpriteID GetCustomAirportSprite(const AirportSpec *as, byte layout)
286 {
287  AirportResolverObject object(INVALID_TILE, nullptr, as->GetIndex(), layout);
288  const SpriteGroup *group = object.Resolve();
289  if (group == nullptr) return as->preview_sprite;
290 
291  return group->GetResult();
292 }
293 
294 uint16 GetAirportCallback(CallbackID callback, uint32 param1, uint32 param2, Station *st, TileIndex tile)
295 {
296  AirportResolverObject object(tile, st, st->airport.type, st->airport.layout, callback, param1, param2);
297  return object.ResolveCallback();
298 }
299 
307 StringID GetAirportTextCallback(const AirportSpec *as, byte layout, uint16 callback)
308 {
309  AirportResolverObject object(INVALID_TILE, nullptr, as->GetIndex(), layout, (CallbackID)callback);
310  uint16 cb_res = object.ResolveCallback();
311  if (cb_res == CALLBACK_FAILED || cb_res == 0x400) return STR_UNDEFINED;
312  if (cb_res > 0x400) {
313  ErrorUnknownCallbackResult(as->grf_prop.grffile->grfid, callback, cb_res);
314  return STR_UNDEFINED;
315  }
316 
317  return GetGRFStringID(as->grf_prop.grffile->grfid, 0xD000 + cb_res);
318 }
AirportSpec::min_year
Year min_year
first year the airport is available
Definition: newgrf_airport.h:109
BaseStation::facilities
StationFacility facilities
The facilities that this station has.
Definition: base_station_base.h:63
TileIndex
uint32 TileIndex
The index/ID of a Tile.
Definition: tile_type.h:78
VarSpriteGroupScope
VarSpriteGroupScope
Definition: newgrf_spritegroup.h:100
RealSpriteGroup::loaded
const SpriteGroup ** loaded
List of loaded groups (can be SpriteIDs or Callback results)
Definition: newgrf_spritegroup.h:92
ResolverObject::callback_param1
uint32 callback_param1
First parameter (var 10) of the callback.
Definition: newgrf_spritegroup.h:334
GRFFileProps::override
uint16 override
id of the entity been replaced by
Definition: newgrf_commons.h:333
GameSettings::station
StationSettings station
settings related to station management
Definition: settings_type.h:561
AirportSpec::IsWithinMapBounds
bool IsWithinMapBounds(byte table, TileIndex index) const
Check if the airport would be within the map bounds at the given tile.
Definition: newgrf_airport.cpp:140
AirportResolverObject::GetFeature
GrfSpecFeature GetFeature() const override
Get the feature number being resolved for.
Definition: newgrf_airport.cpp:232
GetAirportTextCallback
StringID GetAirportTextCallback(const AirportSpec *as, byte layout, uint16 callback)
Get a custom text for the airport.
Definition: newgrf_airport.cpp:307
grfmsg
void CDECL grfmsg(int severity, const char *str,...)
DEBUG() function dedicated to newGRF debugging messages Function is essentially the same as DEBUG(grf...
Definition: newgrf.cpp:379
_cur_year
Year _cur_year
Current year, starting at 0.
Definition: date.cpp:26
AirportSpec::size_y
byte size_y
size of airport in y direction
Definition: newgrf_airport.h:106
Station
Station data structure.
Definition: station_base.h:450
RealSpriteGroup::num_loaded
byte num_loaded
Number of loaded groups.
Definition: newgrf_spritegroup.h:90
AirportSpec::max_year
Year max_year
last year the airport is available
Definition: newgrf_airport.h:110
INSTANTIATE_NEWGRF_CLASS_METHODS
#define INSTANTIATE_NEWGRF_CLASS_METHODS(name, Tspec, Tid, Tmax)
Force instantiation of the methods so we don't get linker errors.
Definition: newgrf_class_func.h:216
ResolverObject
Interface for SpriteGroup-s to access the gamestate.
Definition: newgrf_spritegroup.h:315
AirportScopeResolver::st
struct Station * st
Station of the airport for which the callback is run, or nullptr for build gui.
Definition: newgrf_airport.cpp:22
ResolverObject::grffile
const GRFFile * grffile
GRFFile the resolved SpriteGroup belongs to.
Definition: newgrf_spritegroup.h:343
AirportScopeResolver::airport_id
byte airport_id
Type of airport for which the callback is run.
Definition: newgrf_airport.cpp:23
AirportScopeResolver::layout
byte layout
Layout of the airport to build.
Definition: newgrf_airport.cpp:24
Airport::layout
byte layout
Airport layout number.
Definition: station_base.h:310
AirportSpec::ResetAirports
static void ResetAirports()
This function initializes the airportspec array.
Definition: newgrf_airport.cpp:155
TileY
static uint TileY(TileIndex tile)
Get the Y component of a tile.
Definition: map_func.h:215
newgrf_class_func.h
DIR_W
@ DIR_W
West.
Definition: direction_type.h:32
CallbackID
CallbackID
List of implemented NewGRF callbacks.
Definition: newgrf_callbacks.h:20
ScopeResolver
Interface to query and set values specific to a single VarSpriteGroupScope (action 2 scope).
Definition: newgrf_spritegroup.h:296
AirportSpec
Defines the data structure for an airport.
Definition: newgrf_airport.h:98
VSG_SCOPE_SELF
@ VSG_SCOPE_SELF
Resolved object itself.
Definition: newgrf_spritegroup.h:103
TileX
static uint TileX(TileIndex tile)
Get the X component of a tile.
Definition: map_func.h:205
SpriteID
uint32 SpriteID
The number of a sprite, without mapping bits and colourtables.
Definition: gfx_type.h:17
MapSizeX
static uint MapSizeX()
Get the size of the map along the X.
Definition: map_func.h:72
NewGRFClass::IsUIAvailable
bool IsUIAvailable(uint index) const
Check whether the spec will be available to the user at some point in time.
Definition: newgrf_airport.cpp:81
RealSpriteGroup::loading
const SpriteGroup ** loading
List of loading groups (can be SpriteIDs or Callback results)
Definition: newgrf_spritegroup.h:93
AirportResolverObject::GetScope
ScopeResolver * GetScope(VarSpriteGroupScope scope=VSG_SCOPE_SELF, byte relative=0) override
Get a resolver for the scope.
Definition: newgrf_airport.cpp:52
ResolverObject::callback_param2
uint32 callback_param2
Second parameter (var 18) of the callback.
Definition: newgrf_spritegroup.h:335
AirportSpec::rotation
const Direction * rotation
the rotation of each tiletable
Definition: newgrf_airport.h:101
BindAirportSpecs
void BindAirportSpecs()
Tie all airportspecs to their class.
Definition: newgrf_airport.cpp:167
AirportSpec::Get
static const AirportSpec * Get(byte type)
Retrieve airport spec for the given airport.
Definition: newgrf_airport.cpp:99
AirportScopeResolver::AirportScopeResolver
AirportScopeResolver(ResolverObject &ro, TileIndex tile, Station *st, byte airport_id, byte layout)
Constructor of the scope resolver for an airport.
Definition: newgrf_airport.cpp:35
AirportResolverObject::ResolveReal
const SpriteGroup * ResolveReal(const RealSpriteGroup *group) const override
Get the real sprites of the grf.
Definition: newgrf_airport.cpp:222
AirportSpec::num_table
byte num_table
number of elements in the table
Definition: newgrf_airport.h:102
DIR_E
@ DIR_E
East.
Definition: direction_type.h:28
BaseStation::random_bits
uint16 random_bits
Random bits assigned to this station.
Definition: base_station_base.h:70
AirportScopeResolver::GetRandomBits
uint32 GetRandomBits() const override
Get a few random bits.
Definition: newgrf_airport.cpp:242
CBID_NO_CALLBACK
@ CBID_NO_CALLBACK
Set when using the callback resolve system, but not to resolve a callback.
Definition: newgrf_callbacks.h:22
PersistentStorageArray::GetValue
TYPE GetValue(uint pos) const
Gets the value from a given position.
Definition: newgrf_storage.h:124
ResolverObject::root_spritegroup
const SpriteGroup * root_spritegroup
Root SpriteGroup to use for resolving.
Definition: newgrf_spritegroup.h:344
PersistentStorage
Class for pooled persistent storage of data.
Definition: newgrf_storage.h:221
AirportSpec::GetIndex
byte GetIndex() const
Get the index of this spec.
Definition: newgrf_airport.h:129
Station::airport
Airport airport
Tile area the airport covers.
Definition: station_base.h:464
NewGRFClass
Struct containing information relating to NewGRF classes for stations and airports.
Definition: newgrf_class.h:19
StationSettings::never_expire_airports
bool never_expire_airports
never expire airports
Definition: settings_type.h:525
_settings_game
GameSettings _settings_game
Game settings of a running game or the scenario editor.
Definition: settings.cpp:80
PersistentStorageArray::StoreValue
void StoreValue(uint pos, int32 value)
Stores some value at a given position.
Definition: newgrf_storage.h:95
safeguards.h
AT_INVALID
@ AT_INVALID
Invalid airport.
Definition: airport.h:42
GetGRFStringID
StringID GetGRFStringID(uint32 grfid, StringID stringid)
Returns the index for this stringid associated with its grfID.
Definition: newgrf_text.cpp:602
NUM_AIRPORTS
@ NUM_AIRPORTS
Maximal number of airports in total.
Definition: airport.h:41
AirportResolverObject
Resolver object for airports.
Definition: newgrf_airport.cpp:46
newgrf_text.h
ResolverObject::GetScope
virtual ScopeResolver * GetScope(VarSpriteGroupScope scope=VSG_SCOPE_SELF, byte relative=0)
Get a resolver for the scope.
Definition: newgrf_spritegroup.cpp:153
MapSizeY
static uint MapSizeY()
Get the size of the map along the Y.
Definition: map_func.h:82
date_func.h
stdafx.h
AirportSpec::specs
static AirportSpec specs[NUM_AIRPORTS]
Specs of the airports.
Definition: newgrf_airport.h:138
NewGRFClass::InsertDefaults
static void InsertDefaults()
Initialise the defaults.
Definition: newgrf_airport.cpp:72
AirportScopeResolver::GetVariable
uint32 GetVariable(byte variable, uint32 parameter, bool *available) const override
Get a variable value.
Definition: newgrf_airport.cpp:200
AirportSpec::IsAvailable
bool IsAvailable() const
Check whether this airport is available to build.
Definition: newgrf_airport.cpp:126
AirportSpec::size_x
byte size_x
size of airport in x direction
Definition: newgrf_airport.h:105
newgrf_spritegroup.h
AirportScopeResolver::StorePSA
void StorePSA(uint pos, int32 value) override
Store a value into the object's persistent storage.
Definition: newgrf_airport.cpp:252
GrfSpecFeature
GrfSpecFeature
Definition: newgrf.h:66
AirportScopeResolver
Resolver for the airport scope.
Definition: newgrf_airport.cpp:21
SpriteGroup::Resolve
virtual const SpriteGroup * Resolve(ResolverObject &object) const
Base sprite group resolver.
Definition: newgrf_spritegroup.h:61
CALLBACK_FAILED
static const uint CALLBACK_FAILED
Different values for Callback result evaluations.
Definition: newgrf_callbacks.h:404
StringID
uint32 StringID
Numeric value that represents a string, independent of the selected language.
Definition: strings_type.h:16
station_base.h
Clamp
static T Clamp(const T a, const T min, const T max)
Clamp a value between an interval.
Definition: math_func.hpp:77
GRFFilePropsBase::spritegroup
const struct SpriteGroup * spritegroup[Tcnt]
pointer to the different sprites of the entity
Definition: newgrf_commons.h:321
AirportSpec::enabled
bool enabled
Entity still available (by default true). Newgrf can disable it, though.
Definition: newgrf_airport.h:117
AirportSpec::preview_sprite
SpriteID preview_sprite
preview sprite for this airport
Definition: newgrf_airport.h:114
NEW_AIRPORT_OFFSET
@ NEW_AIRPORT_OFFSET
Number of the first newgrf airport.
Definition: airport.h:39
AirportClassID
AirportClassID
List of default airport classes.
Definition: newgrf_airport.h:68
AirportResolverObject::AirportResolverObject
AirportResolverObject(TileIndex tile, Station *st, byte airport_id, byte layout, CallbackID callback=CBID_NO_CALLBACK, uint32 callback_param1=0, uint32 callback_param2=0)
Constructor of the airport resolver.
Definition: newgrf_airport.cpp:278
OverrideManagerBase::GetSubstituteID
uint16 GetSubstituteID(uint16 entity_id) const
Gives the substitute of the entity, as specified by the grf file.
Definition: newgrf_commons.cpp:166
OrthogonalTileArea::tile
TileIndex tile
The base tile of the area.
Definition: tilearea_type.h:17
RealSpriteGroup
Definition: newgrf_spritegroup.h:79
AirportSpec::grf_prop
struct GRFFileProps grf_prop
Properties related to the grf file.
Definition: newgrf_airport.h:118
APC_MAX
@ APC_MAX
maximum number of airport classes
Definition: newgrf_airport.h:74
OverrideManagerBase::ResetOverride
void ResetOverride()
Resets the override, which is used while initializing game.
Definition: newgrf_commons.cpp:88
Pool::PoolItem<&_persistent_storage_pool >::CanAllocateItem
static bool CanAllocateItem(size_t n=1)
Helper functions so we can use PoolItem::Function() instead of _poolitem_pool.Function()
Definition: pool_type.hpp:299
ResolverObject::callback
CallbackID callback
Callback being resolved.
Definition: newgrf_spritegroup.h:333
NewGRFClass::name
StringID name
Name of this class.
Definition: newgrf_class.h:39
AirportSpec::GetWithoutOverride
static AirportSpec * GetWithoutOverride(byte type)
Retrieve airport spec for the given airport.
Definition: newgrf_airport.cpp:119
lengthof
#define lengthof(x)
Return the length of an fixed size array.
Definition: stdafx.h:367
NewGRFClass::Get
static NewGRFClass * Get(Tid cls_id)
Get a particular class.
Definition: newgrf_class_func.h:103
Airport::type
byte type
Type of this airport,.
Definition: station_base.h:309
RealSpriteGroup::num_loading
byte num_loading
Number of loading groups.
Definition: newgrf_spritegroup.h:91
OverrideManagerBase::max_offset
uint16 max_offset
what is the length of the original entity's array of specs
Definition: newgrf_commons.h:197
INVALID_TILE
static const TileIndex INVALID_TILE
The very nice invalid tile marker.
Definition: tile_type.h:83
OverrideManagerBase::AddEntityID
virtual uint16 AddEntityID(byte grf_local_id, uint32 grfid, byte substitute_id)
Reserves a place in the mapping array for an entity to be installed.
Definition: newgrf_commons.cpp:123
OverrideManagerBase::GetGRFID
uint32 GetGRFID(uint16 entity_id) const
Gives the GRFID of the file the entity belongs to.
Definition: newgrf_commons.cpp:156
GRFFilePropsBase::local_id
uint16 local_id
id defined by the grf file for this entity
Definition: newgrf_commons.h:319
ErrorUnknownCallbackResult
void ErrorUnknownCallbackResult(uint32 grfid, uint16 cbid, uint16 cb_res)
Record that a NewGRF returned an unknown/invalid callback result.
Definition: newgrf_commons.cpp:516
ScopeResolver::ro
ResolverObject & ro
Surrounding resolver object.
Definition: newgrf_spritegroup.h:297
GRFFilePropsBase::grffile
const struct GRFFile * grffile
grf file that introduced this entity
Definition: newgrf_commons.h:320
Swap
static void Swap(T &a, T &b)
Type safe swap operation.
Definition: math_func.hpp:215
AirportResolverObject::GetDebugID
uint32 GetDebugID() const override
Get an identifier for the item being resolved.
Definition: newgrf_airport.cpp:237
Airport::psa
PersistentStorage * psa
Persistent storage for NewGRF airports.
Definition: station_base.h:313
AirportSpec::table
const AirportTileTable *const * table
list of the tiles composing the airport
Definition: newgrf_airport.h:100
BaseStation::build_date
Date build_date
Date of construction.
Definition: base_station_base.h:68
SpriteGroup
Definition: newgrf_spritegroup.h:57
AirportOverrideManager
Definition: newgrf_commons.h:259
OverrideManagerBase::invalid_ID
uint16 invalid_ID
ID used to detected invalid entities;.
Definition: newgrf_commons.h:200
debug.h
DAYS_TILL_ORIGINAL_BASE_YEAR
#define DAYS_TILL_ORIGINAL_BASE_YEAR
The offset in days from the '_date == 0' till 'ConvertYMDToDate(ORIGINAL_BASE_YEAR,...
Definition: date_type.h:80
AirportScopeResolver::tile
TileIndex tile
Tile for the callback, only valid for airporttile callbacks.
Definition: newgrf_airport.cpp:25