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.
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
building_flags		HOUSE_FLAG_XX with XX = [SIZE_1x1, SIZE_2x1, SIZE_1x2, SIZE_2x2, NOT_SLOPED, ANIMATE, CHURCH, STADIUM, ONLY_SE, PROTECTED, SYNC_CALLBACK, RANDOM_ANIMATION]
population	0 ... 255	number of inhabitants the building adds to the town, if present
mail_multiplier	0 ... 255
pax_acceptance	0 ... 1	Can be increased in steps of 0.125. A station accepts a cargo, if the combined acceptance of all houses in range is at least 1.
mail_acceptance	0 ... 1
cargo_acceptance	0 ... 1	Like passenger acceptance. Additionally flag can be added which defines one of the cargo type: HOUSE_ACCEPT_GOODS, HOUSE_ACCEPT_FOOD, HOUSE_ACCEPT_FIZZY_DRINKS; FIZZY_DRINKS has in toyland the same meaning as FOOD in other climates.
accepted_cargo		up to three cargo labels, e.g. MAIL, PASS, COAL
local_authority_impact	0 ... 65525	amount of happiness increase of the city council, if the building is destroyed
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]	NON_LOOPING], 1..128 frames
animation_speed	2 ... 16	Speed of animation, see animation speed table for the meaning of the values.
building_class	0 .. 255	An arbitrary number. You can check for the presence of buildings of the same class when building new buildings or using animation

House variables

House variables are not yet implemented in NML

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 random bits, if enabled in the special_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 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.
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