NML:Houses

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Preface

Getting started

Graphics files

Blocks

Units

Expressions

Elementary values

Builtin functions

Language files

Lists of props, vars and CBs

Warnings

Additional references

NewGRF compatibility

Deprecated syntax

Changes from NML 0.2 to 0.3

Changes from NML 0.3 to 0.4

Changes from NML 0.4 to 0.5

Vehicles, Stations, Canals, Bridges, Towns, Houses, Industries (Tiles), Cargos, Airports+Tiles, Objects, Railtypes, Roadtypes, Tramtypes, Terrain

NML Tutorial

Props, Vars and CBs

General

• variables

Vehicles

• common props | vars | CBs
• train | roadveh | ship | aircr props

Stations

• properties | variables | callbacks

Canals

• properties | variables | callbacks

Bridges

• properties | variables | callbacks

Towns

Houses

• properties | variables | callbacks

Industries

• common variables
• industry props | vars | CBs
• tile props | vars | CBs

Cargos

• properties | variables | callbacks

Airports

• airport props | vars | CBs
• tile props | vars | CBs

Objects

• properties | variables | callbacks

Railtypes

• properties | variables | callbacks

Roadtypes

• properties | variables | callbacks

Tramtypes

• properties | variables | callbacks

House properties

property	value range	comment
name	string	for example string(STR_NAME_EIFFEL_TOWER)
substitute	0 ... 109	Number of the default house that replaces this one, if this house is not available for some reason. This property must be set first, before any other properties or graphics. All properties of the old type are copied to your new house, except for the church / stadium flags (see below). The old house must have the same size as the new house, see the list of default house types for a list of possible substitute IDs.
override	0 ... 109	id of the default house which this house replaces. This will cause your house to be placed instead of the default house. This is ignored, if the default house has already been overridden. You can define this property multiple times. Your house and the overridden house must have the same size, see the list of default house types.
building_flags.	bitmask(HOUSE_FLAG_XXX,...)	HOUSE_FLAG_NOT_SLOPED Can only be built on flat terrain. Note that 2x2 buildings will always only be built on flat land, even if this bit isn't set. HOUSE_FLAG_ANIMATE Enable animation HOUSE_FLAG_CHURCH House is a church (only 1 will be built per town) HOUSE_FLAG_STADIUM House is a stadium (only 1 will be built per town) HOUSE_FLAG_ONLY_SE Can only be built in the scenario editor HOUSE_FLAG_PROTECTED Will not be removed by the game HOUSE_FLAG_SYNC_CALLBACK Animation callback anim_control is called at the same time for all tiles. HOUSE_FLAG_RANDOM_ANIMATION Enable random bits in the anim_next_frame-callback.
population	0 ... 255	number of inhabitants the building adds to the town, if present
mail_multiplier	0 ... 255
accepted_cargos	Array with up to 3 [cargo_id, amount]-pairs.	The cargos that are accepted by each tile of the house. CargoID is a cargo type from your cargo translation table, amount is the acceptance of the given cargo in 1/8 units. Example: to make a tile fully accept both PASS and MAIL you could use this: accepted_cargos: [[PASS, 8], [MAIL, 8]]; Example: for a house tile that doesn't accept any cargos at all you'd use: accepted_cargos: [];
local_authority_impact	0 ... 65525	amount of happiness decrease of the city council, if the building is destroyed. Town ratings can vary between -1000 (appalling) and +1000 (outstanding).
removal_cost_multiplier	0 ... 255
probability	0 ... 16 (float)	Probability with respect to the default houses (=1). Mind that these are relative probabilities with respect to all houses defined. If all probabilities are defined as 16, they'll all have the same probability as if they had all a probability of 1.
years_available	array of two int	[xx, yy] where xx and yy indicate the introduction year and the last year the building can be built
minimum_lifetime	0 ... 255	number of years the building will remain at least
availability_mask	[bitmask(town zones), bitmask(CLIMATE_XXX, ...)]	An array with two bitmasks, the first bitmask is a mask of town zones where this house is available. The second bitmask is a mask of climates combined with the special value ABOVE_SNOWLINE which you need to set for houses available in the arctic climate above the snowline. Examples: Available in the centre town zone in toyland only: [bitmask(TOWNZONE_CENTRE), bitmask(CLIMATE_TOYLAND)] Available in all town zones in the arctic climate both above and below the snowline: [ALL_TOWNZONES, bitmask(CLIMATE_ARCTIC, ABOVE_SNOWLINE)] Available everywhere except on the town edge: [ALL_TOWNZONES & ~bitmask(TOWNZONE_EDGE), ALL_CLIMATES | bitmask(ABOVE_SNOWLINE)
callback_flags	bitmask(HOUSE_CBF_XX)	Do not set this, unless you use old-style callbacks.
random_colours	array of 4, each COLOUR_XXX	colour values in an array, refer to the table here for a list of possible values.
refresh_multiplier	0 ... 63	Defines the frequency with which the tile will be re-randomized which has an impact for random animation.
animation_info	Array [ANIMATION_XXX, frame-count]	Type of animation and its length (1...128 frames): ANIMATION_LOOPING ANIMATION_NON_LOOPING
animation_speed	2 ... 16	Speed of animation, see animation speed table for the meaning of the values.
building_class	0 .. 254	An arbitrary number. You can check for the presence of buildings of the same class when building new buildings or using animation. Only the north tile of a multi-tile building is assigned a class.
watched_cargo_types	array of values from your cargo table	1.2 2.6List of cargo types to watch, to be used with the watched_cargo_accepted callback.

House variables

name	value range	comment
construction_state	0..3	Current construction state of the industry tile
pseudo_random_bits	0..3	Some pseudo-random bits, based on the tile position. TTD houses use this to randomize their appearance.
age	0..255	Age of the house in years, limited to 255
town_zone	town zone	The town zone of the current tile
terrain_type	TILETYPE_XX	TILETYPE_NORMAL, TILETYPE_DESERT, TILETYPE_RAIN_FOREST, TILETYPE_SNOW
same_house_count_town	0..255	Number of the houses with the same ID in the same town as this house
same_house_count_map	0..255	Number of the houses with the same ID on the entire map
same_class_count_town	0..255	Number of the houses with the same building_class in the same town as this house
same_class_count_map	0..255	Number of the houses with the same building_class on the entire map
generating_town	[0 | 1]	1 a random town is currently being created, 0 otherwise. Note that while generating a random town, town variables population and building_count are incorrect. The population variable contains the population of buildings generated yet, the final value may be larger. The building_count is surely higher than the final value will be.
animation_frame	0..255	Current animation frame
x_coordinate	0..2047	X-coordinate (top right -> bottom left) of the tile on the map
y_coordinate	0..2047	Y-coordinate (top left -> bottom right) of the tile on the map

The following variables require one or more arguments

name	arguments	value range	comment
old_house_count_town	ID of old house type (0..109)	0..255	Number of old houses with a given ID in the same town as the current house
old_house_count_town	ID of old house type (0..109)	0..255	Number of old houses with a given ID on the whole map
other_house_count_town	ID of house defined in this NewGRF (0..255)	0..255	Number of houses with a given ID in the same town as the current house
other_house_count_map	ID of house defined in this NewGRF (0..255)	0..255	Number of houses with a given ID on the whole map
other_class_count_town	ID of house defined in this NewGRF (0..255)	0..255	Number of houses, with the same class as the house with the given ID, in the same town as the current house
other_class_count_map	ID of house defined in this NewGRF (0..255)	0..255	Number of houses, with the same class as the house with the given ID, on the whole map
nearby_tile_slope	x- and y-offset (both signed, range -8..7)	SLOPE_XXX	See tile slopes for an overview of possible values
nearby_tile_is_water	x- and y-offset (both signed, range -8..7)	[0 | 1]	1 if the tile is water, 0 otherwise
nearby_tile_terrain_type	x- and y-offset (both signed, range -8..7)	TILETYPE_XX	TILETYPE_NORMAL, TILETYPE_DESERT, TILETYPE_RAIN_FOREST, TILETYPE_SNOW
nearby_tile_water_class	x- and y-offset (both signed, range -8..7)	WATER_CLASS_XXX	XXX = [NONE | SEA | CANAL | RIVER] Note that tiles for which nearby_tile_is_water is 0 may still have a water class, e.g. industry tiles with water beneath them.
nearby_tile_height	x- and y-offset (both signed, range -8..7)	0..255 (currently limited to 0..15)	Height of the lowest corner of the tile. 1 unit is one height level of 8 pixels.
nearby_tile_class	x- and y-offset (both signed, range -8..7)	Tile class
nearby_tile_animation_frame	x- and y-offset (both signed, range -8..7)	0..255	Animation frame of the given tile
cargo_accepted_nearby_ever	cargo type, x- and y-offset	[0 | 1]	1 if the given cargo type was ever accepted at a nearby station, 0 otherwise
cargo_accepted_nearby_last_month	cargo type, x- and y-offset	[0 | 1]	1 if the given cargo type was accepted at a nearby station in the last month, 0 otherwise
cargo_accepted_nearby_this_month	cargo type, x- and y-offset	[0 | 1]	1 if the given cargo type was ever accepted at a nearby station in this month, 0 otherwise
cargo_accepted_nearby_last_bigtick	cargo type, x- and y-offset	[0 | 1]	1 if the given cargo type was ever accepted at a nearby station since the last periodic processing, which happens every 250 ticks. 0 otherwise
cargo_accepted_nearby_watched	cargo type, x- and y-offset	[0 | 1]	1 if the given cargo type was one of the cargo types that triggered the watched_cargo_accepted-callback (only during this callback), 0 otherwise
nearest_house_matching_criterion	radius (1..63) and criterion (SEARCH_HOUSE_BY_XXX, XXX = [ID | CLASS | GRFID])	1..63, or 0 if not found	Perform a circular search for a house matching either the id, building_class or GRFID of this house, depending on the second parameter. The first parameter specifies the maximum search radius. Return value is the Manhattan distance of the closest matching house tile, or 0 if no match was found. Note that tiles of the originating house never match.
nearby_tile_house_id	x- and y-offset (both signed, range -8..7)	-1, or 0 .. 767	Return value is -1 if the tile is not a house tile, X (0..255) if the tile contains old house type X, 256+X if the tile contains a house from this NewGRF with ID X, 512+X if the tile contains a house from a different NewGRF with ID X.
nearby_tile_house_class	x- and y-offset (both signed, range -8..7)	-1, 0, or 256 .. 767	Return value is -1 if the tile is not a house tile, 0 if the house tile does not have a class (this includes all old house types), 256+X (X = 0..255) if the house has been defined by this NewGRF with building_class X or 512+X if the house has been defined by a different NewGRF with building_class X.
nearby_tile_house_grfid	x- and y-offset (both signed, range -8..7)	-1, 0 or a GRFID	Return value is -1 if the tile is not a house tile, 0 if the house tile contains an old house type, or else the GRFID of the NewGRF defining the house.

House callbacks

callback	return value	comment
default	Sprite layout	Graphics for the house tile
random_trigger	N/A	See random switch for more information.
anim_next_frame	Next animation frame or CB_RESULT_XXX	Called for every animation frame, returns the next frame to display. Alternatively, return CB_RESULT_NEXT_FRAME or CB_RESULT_STOP_ANIMATION to show the next frame or stop animation, respectively. extra_callback_info1 contains 32 random bits, if enabled in the building_flags property. Returning a sound effect in the high byte will cause that sound effect to be played.
anim_control	Next animation frame or CB_RESULT_XXX	STOP_ANIMATION | DO_NOTHING] to respectively start the animation in its current frame, stop the animation or do nothing. extra_callback_info1 contains 32 random bits. The low 16 bits are always different for each house tile, but the high 16 bits are the same for each tile if synchronized animation is enabled in the building_flags-property. Returning a sound effect in the high byte will cause that sound effect to be played.
construction_anim	Same as anim_control	Works the same as the anim_control callback, except that it's called when the construction state changes.
watched_cargo_accepted	Same as anim_control	Works the same as the anim_control callback, except that it's called when one of the watched cargo types is accepted.
anim_speed	0 .. 16	Decide the time an animation frame should last. Return value is interpreted as (num_ticks = 2^anim_speed), which each tick lasting 30 ms. Avoid using this callback if possible, since it has to be called each tick for every animated tile. This can be used to create animation frames that last between 30 ms and 33 minutes.
cargo_type_accept	type1 + (type2 << 5) + (type3 << 10)	Decide the cargo types that this tile accepts. If this callback is not implemented or fails, the values from accepted_cargo are used instead. Bits 0..4: First cargo type. Bits 5..9: Second cargo type. Bits 10..14: Third cargo type.
cargo_amount_accept	amt1 + (amt2 << 4) + (amt3 << 8)	Acceptance for each cargo amount in 1/8th. If this callback is not implemented or fails, the values from the acceptance properties are used instead. Cargo types are from the cargo_type_accept callback, or the accepted_cargo property if that callback failed. Bits 0..3: Acceptance of first cargo type. Bits 4..7: Acceptance of second cargo type. Bits 8..11: Acceptance of third cargo type.
cargo_production	(cargo_type * 256) + amount	Called every 256 ticks. Called multiple times until 0x20FF is returned. The high byte of the result contains a cargo type, the low byte contains the amount of that cargo to produce. extra_callback_info1 contains the number of iterations so far, extra_callback_info2 contains random bits.
foundations	CB_RESULT[_NO]_FOUNDATIONS	Return CB_RESULT_FOUNDATIONS to draw standard foundations (default) or CB_RESULT_NO_FOUNDATIONS to not draw them.
autoslope	CB_RESULT[_NO]_AUTOSLOPE	Return CB_RESULT_AUTOSLOPE to allow autoslope (altering the ground below a tile) or CB_RESULT_NO_AUTOSLOPE to disallow it.
name	String	Name of the building (when using tile query tool)
colour	Palette number	Used to recolour the building. See here here for an overview of default palettes.
construction_check	0 or 1	Return 1 to allow building the house or 0 to disallow.
destruction	0 or 1	Called periodically. Return 0 to keep the building or 1 to destroy it.
protection	0 or 1	Return 0 to allow destruction, or 1 to disallow