Difference between revisions of "NML:Objects"

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==Object IDs==
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Object IDs are NewGRF-local and can therefore freely be chosen in the 0..255 range. An object is allocated by setting the 'class'-property, which should therefore be set first. Overriding the default objects (e.g. transmitter, lighthouse) is not (yet) possible.
   
 
==Object properties==
 
==Object properties==

Revision as of 20:11, 2 August 2012

Props, Vars and CBs

Object IDs

Object IDs are NewGRF-local and can therefore freely be chosen in the 0..255 range. An object is allocated by setting the 'class'-property, which should therefore be set first. Overriding the default objects (e.g. transmitter, lighthouse) is not (yet) possible.

Object properties

property value range comment
class String literal of length 4

Unlike station classes, there is currently no default yet. You have to set the class ID before any other property or graphics. Characters allowed in the IDs are A-Z, 0-9. While you are technically free to chose your own class, it's highly recommended you stick to one of the default classes.

classname string You only need to set this for one object in every class.
name string
climates_available bitmask(CLIMATE_XXX, CLIMATE_YYY, ...) XXX = [TEMPERATE | ARCTIC | TROPICAL | TOYLAND], alternatively NO_CLIMATE or ALL_CLIMATES
size [x, y] Size in x and y direction. Both x and y must be compiletime constants
build_cost_multiplier multiplicator to the base purchase cost
remove_cost_multiplier multiplicator to the base removal cost
introduction_date date The date this object becomes available to build.
end_of_life_date date The last date this object is buildable. Must be at least 365 days after introduction_date
object_flags bitmask(OBJ_FLAG_XXX, OBJ_FLAG_YYY)

See list of object flags

animation_info Array [ANIMATION_XXX, frame-count] XXX = [LOOPING | NON_LOOPING], 1..253 frames
animation_speed 0..16

Speed of animation, see animation speed table for the meaning of the values.

animation_triggers
callback_flags bitmask(OBJ_CBF_XXX, OBJ_CBF_YYY)

Do not set this, unless you use old-style callbacks.

height 0..255 Height of the object / 8. For example if your object is 16 pixels height you should set height to 2. In OpenTTD this property is used to determine the height of the build object window; the height for the object preview is set to 32 + "value of property" * 8. The property is also used to determine how high a bridge must be if it is allowed by the bit in object_flags.
num_views 1, 2 or 4 Objects may have "views", i.e. different graphical representations, e.g. used to show rotated views of an object. Number of views may be 1, 2, or 4. Default value is 1. For non-square objects, x and y sizes are swapped for odd views. Use variable view to determine the view of a built object.

Default object classes

Please refer to the list of object labels in the NewGRF Specs. The default class names listed there are recommended, you still need to set the class name for at least one object in every class or you risk to end up with objects in a class without a name. If multiple NewGRFs define objects for the same class the name defined in the last NewGRF will be used.

List of object flags

Name Meaning
OBJ_FLAG_ONLY_SE Only available in the scenario editor (incompatible with OBJ_FLAG_ONLY_INGAME)
OBJ_FLAG_IRREMOVABLE Object cannot be removed with the normal dynamite tool. In OpenTTD you can only remove the object with the magic bulldozer cheat, in TTDPatch you can remove it by holding ctrl while using the bulldozer tool. The cost of removing this object is multiplied by 25.
OBJ_FLAG_ANYTHING_REMOVE Anything can remove this object (owned land behavior)
OBJ_FLAG_ON_WATER Allow construction of the object on water
OBJ_FLAG_REMOVE_IS_INCOME Removal cost is actually income (owned land behaviour)
OBJ_FLAG_NO_FOUNDATIONS Do not display foundations if on a slope
OBJ_FLAG_ANIMATED Setting this flag will allow the object's animation counter to be increased, must be set if you plan to make use of animations.
OBJ_FLAG_ONLY_INGAME Only available during game play (incompatible with OBJ_FLAG_ONLY_SE)
OBJ_FLAG_2CC Allows 2cc mapping for objects instead of the default 1cc
OBJ_FLAG_NOT_ON_LAND Disallows construction on land (implies OBJ_FLAG_ON_WATER)
OBJ_FLAG_DRAW_WATER Draws the water under the object. Only applies when built on top of a water tile, also replaces the ground tile of the object completely. Does not work when object built on sloped water tiles.
OBJ_FLAG_ALLOW_BRIDGE Allow bridge over the object taking the building height into account.
OBJ_FLAG_RANDOM_ANIMATION Random bits in the "next animation frame" callback


Object variables

name value range comment
relative_x 0..255 X-coordinate (top right -> bottom left) of the tile relative to the northernmost tile.
relative_y 0..255 Y-coordinate (top left -> bottom right) of the tile relative to the northernmost tile.
relative_pos 0xYYXX

A combination of relative_x and relative_y in the format 0xYYXX. Useful if you want to check for a single position. The builtin function relative_coord(x, y) may be useful when making comparisons.

terrain_type TILETYPE_NORMAL, TILETYPE_DESERT, TILETYPE_RAIN_FOREST, TILETYPE_SNOW
tile_slope SLOPE_XXX

See tile slopes for an overview of possible values

build_date The date this object was build.
animation_frame 0..255 Current animation frame
company_colour COLOUR_XXX

Colour used for the company colour mask. Refer to the table here for possible values.

owner 0..0x10 CompanyID of the owner of the object or 0x10 if it was build in the scenario editor
town_manhattan_dist Manhattan distance to the nearest town
town_euclidean_dist Euclidean distance to the nearest town
town_zone

town zone

The town zone of the current tile. The town zone from the closest town (measured in manhattan distance) is used.
view 0 .. num_views - 1

Supported by OpenTTD 1.1 (r21455)1.1 The view of the particular object. See also the num_views property.

Variables that require one or more parameters:

name arguments value range comment
nearby_tile_object_type x, y offset (-8..7) ID of the object on a nearby tile, if defined by the same grf. OBJECT_TYPE_OTHER_GRF if the object is defined by a different grf (or none at all). OBJECT_TYPE_NO_OBJECT if the tile does not contain an object.
nearby_tile_random_bits x, y offset (-8..7) Random bits of the given tile
nearby_tile_slope x, y offset (-8..7) See tile_slope
nearby_tile_is_same_object x, y offset (-8..7) 0 .. 1 Is the given tile part of the same object?
nearby_tile_is_water x, y offset (-8..7) 0 .. 1 Is the given tile a water tile?
nearby_tile_terrain_type x, y offset (-8..7) See terrain_type
nearby_tile_water_class x, y offset (-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, y offset (-8..7) 0 .. 120 The minimum height of the given tile. 8 units correspond to one height level
nearby_tile_class x, y offset (-8..7)

Tile class

nearby_tile_animation_frame x, y offset (-8..7) See animation_frame
object_count object id [, grfid] 0..0xFFFF

Number of objects with the given object id currently on the map. Grfid is the grfid of the newgrf you want to check the object count of (default is current grf). Use the builtin function str2number() to convert a grfid to its numeric representation.

object_distance object id [, grfid] 0..0xFFFF

Manhattan distance to the closest object of the given type. Grfid is the grfid of the newgrf you want to check the minimum object distance of (default is current grf). Use the builtin function str2number() to convert a grfid to its numeric representation. If the given object type is not yet built, this will return 0xFFFF


Object callbacks

callback return value comment
default Sprite layout Normal graphics for an object placed on the map
purchase* Sprite layout Graphics shown in the build menu
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 the object flag OBJ_FLAG_RANDOM_ANIMATION is set. Returning a sound effect in the high byte will cause that sound effect to be played (e.g. return (sound("mysound.wav") << 8) | CB_RESULT_NEXT_FRAME;).
anim_control Next animation frame or CB_RESULT_XXX

Called whenever an object animation trigger happens. Return the animation frame to show, or CB_RESULT_XXX with XXX = [CB_RESULT_START_ANIMATION | 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 the object flag OBJ_FLAG_RANDOM_ANIMATION is set. extra_callback_info2 contains the reason to trigger the animation, see the table below. Returning a sound effect in the high byte will cause that sound effect to be played.

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.
colour colour2*16 + colour1

Called once, just after construction. Variable extra_callback_info1 contains the colour scheme of the constructing company in the same format as the return value, or random colours if not available (scenario editor). If OBJ_FLAG_2CC is not set, colour2 is zero. This callback can be used to alter the colour scheme of an object. Refer to the table here for possible colour values.

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.
tile_check*

Same as for the location_check industry callback

Parameters: extra_callback_info1 contains the slope in bits 0..4 (see below), all other bits are reserved and should be and-masked out. extra_callback_info2 contains the location of the tile within the object as 16*y + x. If this callback is not implemented or fails, the default behaviour is to allow building the object if it can be placed on a flat surface. This means that steep slopes are not allowed and that the highest corner of each tile of a multi-tile object should have the same height. Additionally, all tiles must be flat if "build on slopes" is disabled.
additional_text* String Additional text to show in the purchase menu

* These callbacks are called when the object is not yet built, so object- specific variables cannot be accessed. Trying to do so will result in undefined behaviour.

Animation triggers

Animation trigger Description
ANIM_TRIGGER_OBJ_BUILT Object is built (all tiles at the same time)
ANIM_TRIGGER_OBJ_TILELOOP Object tile is processed in the tileloop (at different times for different tiles)
ANIM_TRIGGER_OBJ_256_TICKS Every 256 ticks (all tiles at the same time)