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 
8 /** @file newgrf_callbacks.h Callbacks that NewGRFs could implement. */
9 
10 #ifndef NEWGRF_CALLBACKS_H
11 #define NEWGRF_CALLBACKS_H
12 
13 /**
14  * List of implemented NewGRF callbacks.
15  * Most of these callbacks are only triggered when the corresponding
16  * bit is set in the callback flags/trigger for a vehicle, house,
17  * industry, etc.
18  * Names are formatted as CBID_<CLASS>_<CALLBACK>
19  */
20 enum CallbackID {
21 	/** Set when using the callback resolve system, but not to resolve a callback. */
22 	CBID_NO_CALLBACK                     = 0x00,
23 
24 	/** Set when calling a randomizing trigger (almost undocumented). */
25 	CBID_RANDOM_TRIGGER                  = 0x01,
26 
27 	/* There are no callbacks 0x02 - 0x0F. */
28 
29 	/** Visual effects and wagon power. */
30 	CBID_VEHICLE_VISUAL_EFFECT           = 0x10, // 8 bit callback
31 
32 	/** Vehicle length, returns the amount of 1/8's the vehicle is shorter for trains and RVs. */
33 	CBID_VEHICLE_LENGTH                  = 0x11,
34 
35 	/** Determine the amount of cargo to load per unit of time when using gradual loading. */
36 	CBID_VEHICLE_LOAD_AMOUNT             = 0x12, // 8 bit callback
37 
38 	/** Determine whether a newstation should be made available to build. */
39 	CBID_STATION_AVAILABILITY            = 0x13, // 8 bit callback
40 
41 	/** Choose a sprite layout to draw, instead of the standard 0-7 range. */
42 	CBID_STATION_SPRITE_LAYOUT           = 0x14,
43 
44 	/**
45 	 * Refit capacity, the passed vehicle needs to have its ->cargo_type set to
46 	 * the cargo we are refitting to, returns the new cargo capacity.
47 	 */
48 	CBID_VEHICLE_REFIT_CAPACITY          = 0x15, // 15 bit callback
49 
50 	/** Builds articulated engines for trains and RVs. */
51 	CBID_VEHICLE_ARTIC_ENGINE            = 0x16, // 8 bit callback for grf version < 8
52 
53 	/** Determine whether the house can be built on the specified tile. */
54 	CBID_HOUSE_ALLOW_CONSTRUCTION        = 0x17, // 8 bit callback
55 
56 	/** AI construction/purchase selection */
57 	CBID_GENERIC_AI_PURCHASE_SELECTION   = 0x18, // 8 bit callback, implemented for stations only
58 
59 	/** Determine the cargo "suffixes" for each refit possibility of a cargo. */
60 	CBID_VEHICLE_CARGO_SUFFIX            = 0x19,
61 
62 	/** Determine the next animation frame for a house. */
63 	CBID_HOUSE_ANIMATION_NEXT_FRAME      = 0x1A, // 15 bit callback
64 
65 	/** Called for periodically starting or stopping the animation. */
66 	CBID_HOUSE_ANIMATION_START_STOP      = 0x1B, // 15 bit callback
67 
68 	/** Called whenever the construction state of a house changes. */
69 	CBID_HOUSE_CONSTRUCTION_STATE_CHANGE = 0x1C, // 15 bit callback
70 
71 	/** Determine whether a wagon can be attached to an already existing train. */
72 	CBID_TRAIN_ALLOW_WAGON_ATTACH        = 0x1D,
73 
74 	/** Called to determine the colour of a town building. */
75 	CBID_HOUSE_COLOUR                    = 0x1E, // 15 bit callback
76 
77 	/** Called to decide how much cargo a town building can accept. */
78 	CBID_HOUSE_CARGO_ACCEPTANCE          = 0x1F, // 15 bit callback
79 
80 	/** Called to indicate how long the current animation frame should last. */
81 	CBID_HOUSE_ANIMATION_SPEED           = 0x20, // 8 bit callback
82 
83 	/** Called periodically to determine if a house should be destroyed. */
84 	CBID_HOUSE_DESTRUCTION               = 0x21, // 8 bit callback
85 
86 	/** Called to determine if the given industry type is available. For grf version >= 8 also a probability can be returned. */
87 	CBID_INDUSTRY_PROBABILITY            = 0x22, // 15 bit callback
88 
89 	/**
90 	 * This callback is called from vehicle purchase lists. It returns a value to be
91 	 * used as a custom string ID in the 0xD000 range.
92 	 */
93 	CBID_VEHICLE_ADDITIONAL_TEXT         = 0x23,
94 
95 	/** Called when building a station to customize the tile layout */
96 	CBID_STATION_TILE_LAYOUT             = 0x24, // 15 bit callback
97 
98 	/** Called for periodically starting or stopping the animation. */
99 	CBID_INDTILE_ANIM_START_STOP         = 0x25, // 15 bit callback
100 
101 	/** Called to determine industry tile next animation frame. */
102 	CBID_INDTILE_ANIM_NEXT_FRAME         = 0x26, // 15 bit callback
103 
104 	/** Called to indicate how long the current animation frame should last. */
105 	CBID_INDTILE_ANIMATION_SPEED         = 0x27, // 8 bit callback
106 
107 	/** Called to determine if the given industry can be built on specific area. */
108 	CBID_INDUSTRY_LOCATION               = 0x28, // 15 bit callback
109 
110 	/** Called on production changes, so it can be adjusted. */
111 	CBID_INDUSTRY_PRODUCTION_CHANGE      = 0x29, // 15 bit callback
112 
113 	/** Called to determine which cargoes a town building should accept. */
114 	CBID_HOUSE_ACCEPT_CARGO              = 0x2A, // 15 bit callback
115 
116 	/** Called to query the cargo acceptance of the industry tile */
117 	CBID_INDTILE_CARGO_ACCEPTANCE        = 0x2B, // 15 bit callback
118 
119 	/** Called to determine which cargoes an industry should accept. */
120 	CBID_INDTILE_ACCEPT_CARGO            = 0x2C, // 15 bit callback
121 
122 	/**
123 	 * Called to determine if a specific colour map should be used for a vehicle
124 	 * instead of the default livery.
125 	 */
126 	CBID_VEHICLE_COLOUR_MAPPING          = 0x2D, // 15 bit callback
127 
128 	/** Called to determine how much cargo a town building produces. */
129 	CBID_HOUSE_PRODUCE_CARGO             = 0x2E, // 15 bit callback
130 
131 	/** Called to determine if the given industry tile can be built on specific tile. */
132 	CBID_INDTILE_SHAPE_CHECK             = 0x2F, // 15 bit callback
133 
134 	/** Called to determine the type (if any) of foundation to draw for industry tile. */
135 	CBID_INDTILE_DRAW_FOUNDATIONS        = 0x30, // 15 bit callback
136 
137 	/**
138 	 * Called when the company (or AI) tries to start or stop a vehicle. Mainly
139 	 * used for preventing a vehicle from leaving the depot.
140 	 */
141 	CBID_VEHICLE_START_STOP_CHECK        = 0x31, // 15 bit callback, but 0xFF test is done with 8 bit
142 
143 	/** Called for every vehicle every 32 days (not all on same date though). */
144 	CBID_VEHICLE_32DAY_CALLBACK          = 0x32, // 2 bit callback
145 
146 	/** Called to play a special sound effect */
147 	CBID_VEHICLE_SOUND_EFFECT            = 0x33, // 15 bit callback
148 
149 	/** Return the vehicles this given vehicle can be "upgraded" to. */
150 	CBID_VEHICLE_AUTOREPLACE_SELECTION   = 0x34, // 15 bit callback, not implemented
151 
152 	/** Called monthly on production changes, so it can be adjusted more frequently */
153 	CBID_INDUSTRY_MONTHLYPROD_CHANGE     = 0x35, // 15 bit callback
154 
155 	/**
156 	 * Called to modify various vehicle properties. Callback parameter 1
157 	 * specifies the property index, as used in Action 0, to change.
158 	 */
159 	CBID_VEHICLE_MODIFY_PROPERTY         = 0x36, // 8/15 bit depends on queried property
160 
161 	/** Called to determine text to display after cargo name */
162 	CBID_INDUSTRY_CARGO_SUFFIX           = 0x37, // 15 bit callback, but 0xFF test is done with 8 bit
163 
164 	/** Called to determine more text in the fund industry window */
165 	CBID_INDUSTRY_FUND_MORE_TEXT         = 0x38, // 15 bit callback
166 
167 	/** Called to calculate the income of delivered cargo */
168 	CBID_CARGO_PROFIT_CALC               = 0x39, // 15 bit callback
169 
170 	/** Called to determine more text in the industry window */
171 	CBID_INDUSTRY_WINDOW_MORE_TEXT       = 0x3A, // 15 bit callback
172 
173 	/** Called to determine industry special effects */
174 	CBID_INDUSTRY_SPECIAL_EFFECT         = 0x3B, // 15 bit callback
175 
176 	/** Called to determine if industry can alter the ground below industry tile */
177 	CBID_INDTILE_AUTOSLOPE               = 0x3C, // 15 bit callback
178 
179 	/** Called to determine if the industry can still accept or refuse more cargo arrival */
180 	CBID_INDUSTRY_REFUSE_CARGO           = 0x3D, // 15 bit callback
181 
182 	/* There are no callbacks 0x3E - 0x13F */
183 
184 	/** Called for periodically starting or stopping the animation. */
185 	CBID_STATION_ANIM_START_STOP         = 0x140, // 15 bit callback
186 
187 	/** Called to determine station tile next animation frame. */
188 	CBID_STATION_ANIM_NEXT_FRAME         = 0x141, // 15 bit callback
189 
190 	/** Called to indicate how long the current animation frame should last. */
191 	CBID_STATION_ANIMATION_SPEED         = 0x142, // 8 bit callback
192 
193 	/** Called to determine whether a town building can be destroyed. */
194 	CBID_HOUSE_DENY_DESTRUCTION          = 0x143, // 15 bit callback
195 
196 	/** Select an ambient sound to play for a given type of tile. */
197 	CBID_SOUNDS_AMBIENT_EFFECT           = 0x144, // 15 bit callback
198 
199 	/** Called to calculate part of a station rating. */
200 	CBID_CARGO_STATION_RATING_CALC       = 0x145, // 15 bit callback
201 
202 	/** Allow signal sprites to be replaced dynamically. */
203 	CBID_NEW_SIGNALS_SPRITE_DRAW         = 0x146, // 15 bit callback, not implemented
204 
205 	/** Add an offset to the default sprite numbers to show another sprite. */
206 	CBID_CANALS_SPRITE_OFFSET            = 0x147, // 15 bit callback
207 
208 	/** Called when a cargo type specified in property 20 is accepted. */
209 	CBID_HOUSE_WATCHED_CARGO_ACCEPTED    = 0x148, // 15 bit callback
210 
211 	/** Callback done for each tile of a station to check the slope. */
212 	CBID_STATION_LAND_SLOPE_CHECK        = 0x149, // 15 bit callback
213 
214 	/** Called to determine the colour of an industry. */
215 	CBID_INDUSTRY_DECIDE_COLOUR          = 0x14A, // 4 bit callback
216 
217 	/** Customize the input cargo types of a newly build industry. */
218 	CBID_INDUSTRY_INPUT_CARGO_TYPES      = 0x14B, // 8 bit callback
219 
220 	/** Customize the output cargo types of a newly build industry. */
221 	CBID_INDUSTRY_OUTPUT_CARGO_TYPES     = 0x14C, // 8 bit callback
222 
223 	/** Called on the Get Tile Description for an house tile. */
224 	CBID_HOUSE_CUSTOM_NAME               = 0x14D, // 15 bit callback
225 
226 	/** Called to determine the type (if any) of foundation to draw for house tile. */
227 	CBID_HOUSE_DRAW_FOUNDATIONS          = 0x14E, // 15 bit callback
228 
229 	/** Called to determine if one can alter the ground below a house tile */
230 	CBID_HOUSE_AUTOSLOPE                 = 0x14F, // 15 bit callback
231 
232 	/** Called to determine the type (if any) of foundation to draw for an airport tile. */
233 	CBID_AIRPTILE_DRAW_FOUNDATIONS       = 0x150, // 15 bit callback
234 
235 	/** Called for periodically starting or stopping the animation. */
236 	CBID_AIRPTILE_ANIM_START_STOP        = 0x152, // 15 bit callback
237 
238 	/** Called to determine airport tile next animation frame. */
239 	CBID_AIRPTILE_ANIM_NEXT_FRAME        = 0x153, // 15 bit callback
240 
241 	/** Called to indicate how long the current animation frame should last. */
242 	CBID_AIRPTILE_ANIMATION_SPEED        = 0x154, // 8 bit callback
243 
244 	/**
245 	 * This callback is called from airport list. It returns a value to be
246 	 * used as a custom string ID in the 0xD000 range.
247 	 */
248 	CBID_AIRPORT_ADDITIONAL_TEXT         = 0x155, // 15 bit callback
249 
250 	/** Called to determine text to show as airport layout name. */
251 	CBID_AIRPORT_LAYOUT_NAME             = 0x156, // 15 bit callback
252 
253 	/** Callback done for each tile of an object to check the slope. */
254 	CBID_OBJECT_LAND_SLOPE_CHECK         = 0x157, // 15 bit callback
255 
256 	/** Determine the next animation frame for a house. */
257 	CBID_OBJECT_ANIMATION_NEXT_FRAME     = 0x158, // 15 bit callback
258 
259 	/** Called for periodically starting or stopping the animation. */
260 	CBID_OBJECT_ANIMATION_START_STOP     = 0x159, // 15 bit callback
261 
262 	/** Called to indicate how long the current animation frame should last. */
263 	CBID_OBJECT_ANIMATION_SPEED          = 0x15A, // 8 bit callback
264 
265 	/** Called to determine the colour of a town building. */
266 	CBID_OBJECT_COLOUR                   = 0x15B, // 15 bit callback
267 
268 	/** Called to determine more text in the fund object window */
269 	CBID_OBJECT_FUND_MORE_TEXT           = 0x15C, // 15 bit callback
270 
271 	/** Called to determine if one can alter the ground below an object tile */
272 	CBID_OBJECT_AUTOSLOPE                = 0x15D, // 15 bit callback
273 
274 	/** Called to determine the cost factor for refitting a vehicle. */
275 	CBID_VEHICLE_REFIT_COST              = 0x15E, // 15 bit callback
276 
277 	/** Called when industry is built to set initial production level. */
278 	CBID_INDUSTRY_PROD_CHANGE_BUILD      = 0x15F, // 15 bit callback
279 
280 	/** Called to spawn visual effects for vehicles. */
281 	CBID_VEHICLE_SPAWN_VISUAL_EFFECT     = 0x160, // 15 bit callback
282 };
283 
284 /**
285  * Callback masks for vehicles, indicates which callbacks are used by a vehicle.
286  * Some callbacks are always used and don't have a mask.
287  */
288 enum VehicleCallbackMask {
289 	CBM_VEHICLE_VISUAL_EFFECT  = 0, ///< Visual effects and wagon power (trains, road vehicles and ships)
290 	CBM_VEHICLE_LENGTH         = 1, ///< Vehicle length (trains and road vehicles)
291 	CBM_VEHICLE_LOAD_AMOUNT    = 2, ///< Load amount
292 	CBM_VEHICLE_REFIT_CAPACITY = 3, ///< Cargo capacity after refit
293 	CBM_VEHICLE_ARTIC_ENGINE   = 4, ///< Add articulated engines (trains and road vehicles)
294 	CBM_VEHICLE_CARGO_SUFFIX   = 5, ///< Show suffix after cargo name
295 	CBM_VEHICLE_COLOUR_REMAP   = 6, ///< Change colour mapping of vehicle
296 	CBM_VEHICLE_SOUND_EFFECT   = 7, ///< Vehicle uses custom sound effects
297 };
298 
299 /**
300  * Callback masks for stations.
301  */
302 enum StationCallbackMask {
303 	CBM_STATION_AVAIL                = 0, ///< Availability of station in construction window
304 	CBM_STATION_SPRITE_LAYOUT        = 1, ///< Use callback to select a sprite layout to use
305 	CBM_STATION_ANIMATION_NEXT_FRAME = 2, ///< Use a custom next frame callback
306 	CBM_STATION_ANIMATION_SPEED      = 3, ///< Customize the animation speed of the station
307 	CBM_STATION_SLOPE_CHECK          = 4, ///< Check slope of new station tiles
308 };
309 
310 /**
311  * Callback masks for houses.
312  */
313 enum HouseCallbackMask {
314 	CBM_HOUSE_ALLOW_CONSTRUCTION        =  0, ///< decide whether the house can be built on a given tile
315 	CBM_HOUSE_ANIMATION_NEXT_FRAME      =  1, ///< decides next animation frame
316 	CBM_HOUSE_ANIMATION_START_STOP      =  2, ///< periodically start/stop the animation
317 	CBM_HOUSE_CONSTRUCTION_STATE_CHANGE =  3, ///< change animation when construction state changes
318 	CBM_HOUSE_COLOUR                    =  4, ///< decide the colour of the building
319 	CBM_HOUSE_CARGO_ACCEPTANCE          =  5, ///< decides amount of cargo acceptance
320 	CBM_HOUSE_ANIMATION_SPEED           =  6, ///< decides animation speed
321 	CBM_HOUSE_DESTRUCTION               =  7, ///< trigger destruction of building
322 	CBM_HOUSE_ACCEPT_CARGO              =  8, ///< decides accepted types
323 	CBM_HOUSE_PRODUCE_CARGO             =  9, ///< custom cargo production
324 	CBM_HOUSE_DENY_DESTRUCTION          = 10, ///< conditional protection
325 	CBM_HOUSE_DRAW_FOUNDATIONS          = 11, ///< decides if default foundations need to be drawn
326 	CBM_HOUSE_AUTOSLOPE                 = 12, ///< decides allowance of autosloping
327 };
328 
329 /**
330  * Callback masks for canals.
331  */
332 enum CanalCallbackMask {
333 	CBM_CANAL_SPRITE_OFFSET       = 0, ///< Enable add sprite offset callback
334 };
335 
336 /**
337  * Callback masks for cargoes.
338  */
339 enum CargoCallbackMask {
340 	CBM_CARGO_PROFIT_CALC         = 0, ///< custom profit calculation
341 	CBM_CARGO_STATION_RATING_CALC = 1, ///< custom station rating for this cargo type
342 };
343 
344 /**
345  * Callback masks for Industries
346  */
347 enum IndustryCallbackMask {
348 	CBM_IND_PROBABILITY               =  0, ///< industry availability/probability callback
349 	CBM_IND_PRODUCTION_CARGO_ARRIVAL  =  1, ///< call production callback when cargo arrives at the industry
350 	CBM_IND_PRODUCTION_256_TICKS      =  2, ///< call production callback every 256 ticks
351 	CBM_IND_LOCATION                  =  3, ///< check industry construction on given area
352 	CBM_IND_PRODUCTION_CHANGE         =  4, ///< controls random production change
353 	CBM_IND_MONTHLYPROD_CHANGE        =  5, ///< controls monthly random production change
354 	CBM_IND_CARGO_SUFFIX              =  6, ///< cargo sub-type display
355 	CBM_IND_FUND_MORE_TEXT            =  7, ///< additional text in fund window
356 	CBM_IND_WINDOW_MORE_TEXT          =  8, ///< additional text in industry window
357 	CBM_IND_SPECIAL_EFFECT            =  9, ///< control special effects
358 	CBM_IND_REFUSE_CARGO              = 10, ///< option out of accepting cargo
359 	CBM_IND_DECIDE_COLOUR             = 11, ///< give a custom colour to newly build industries
360 	CBM_IND_INPUT_CARGO_TYPES         = 12, ///< customize the cargoes the industry requires
361 	CBM_IND_OUTPUT_CARGO_TYPES        = 13, ///< customize the cargoes the industry produces
362 	CBM_IND_PROD_CHANGE_BUILD         = 14, ///< initialise production level on construction
363 };
364 
365 /**
366  * Callback masks for industry tiles
367  */
368 enum IndustryTileCallbackMask {
369 	CBM_INDT_ANIM_NEXT_FRAME          = 0,  ///< decides next animation frame
370 	CBM_INDT_ANIM_SPEED               = 1,  ///< decides animation speed
371 	CBM_INDT_CARGO_ACCEPTANCE         = 2,  ///< decides amount of cargo acceptance
372 	CBM_INDT_ACCEPT_CARGO             = 3,  ///< decides accepted types
373 	CBM_INDT_SHAPE_CHECK              = 4,  ///< decides slope suitability
374 	CBM_INDT_DRAW_FOUNDATIONS         = 5,  ///< decides if default foundations need to be drawn
375 	CBM_INDT_AUTOSLOPE                = 6,  ///< decides allowance of autosloping
376 };
377 
378 /**
379  * Callback masks for objects
380  */
381 enum ObjectCallbackMask {
382 	CBM_OBJ_SLOPE_CHECK               =  0, ///< decides slope suitability
383 	CBM_OBJ_ANIMATION_NEXT_FRAME      =  1, ///< decides next animation frame
384 	CBM_OBJ_ANIMATION_SPEED           =  2, ///< decides animation speed
385 	CBM_OBJ_COLOUR                    =  3, ///< decide the colour of the building
386 	CBM_OBJ_FUND_MORE_TEXT            =  4, ///< additional text in fund window
387 	CBM_OBJ_AUTOSLOPE                 =  5, ///< decides allowance of autosloping
388 };
389 
390 /**
391  * Callback masks for airport tiles
392  */
393 enum AirportTileCallbackMask {
394 	CBM_AIRT_ANIM_NEXT_FRAME          = 0,  ///< decides next animation frame
395 	CBM_AIRT_ANIM_SPEED               = 1,  ///< decides animation speed
396 	CBM_AIRT_SHAPE_CHECK              = 4,  ///< decides slope suitability
397 	CBM_AIRT_DRAW_FOUNDATIONS         = 5,  ///< decides if default foundations need to be drawn
398 	CBM_AIRT_AUTOSLOPE                = 6,  ///< decides allowance of autosloping
399 };
400 
401 /**
402  * Different values for Callback result evaluations
403  */
404 static const uint CALLBACK_FAILED              = 0xFFFF; ///< Result of a failed callback.
405 static const uint CALLBACK_HOUSEPRODCARGO_END  = 0x20FF; ///< Sentinel indicating that the loop for CBID_HOUSE_PRODUCE_CARGO has ended
406 
407 #endif /* NEWGRF_CALLBACKS_H */
408