Mappers

Mappers always follow a getter or another mapper, and transform the previous value into a new value. They sometimes take an argument, which can be a literal or a value_of() expression.

The available mappers depend on the type of the preceding value.

BlockPos

Produced by: pos, string as_block_pos, vec_pos rounded_down

Mapper Output Description
x Int X coordinate
y Int Y coordinate
z Int Z coordinate
center Vec Pos The centered floating-point position (x + 0.5, y + 0.5, z + 0.5)
offset_x <int> BlockPos Returns a new position offset by the given amount on the X axis
offset_y <int> BlockPos Returns a new position offset by the given amount on the Y axis
offset_z <int> BlockPos Returns a new position offset by the given amount on the Z axis
offset <coords> BlockPos Returns a new position offset by the given coordinate components
== <coords> Boolean True if equal to the given position
as_string String Formats as "x y z"

Examples:

if pos x > 0 set_redstone 15
set_redstone value_of(pos y & 15)

BlockState

Produced by: block

Mapper Output Description
== <block predicate> Boolean True if the block state matches the predicate (supports block properties)
id String The block’s id, such as "minecraft:stone", without its properties

Examples:

if block == minecraft:stone set_redstone 15
if block == minecraft:piston[facing=up] set_redstone 15
if block id == value_of(page_contents) set_redstone 15

Item

Produced by: held_item

Mapper Output Description
== <item predicate> Boolean True if the item matches the predicate
count Int The stack size; 0 for an empty hand
id String The item’s id, such as "minecraft:stone"; "minecraft:air" for an empty hand

== only takes an item written in the script. To compare against text the script reads or receives, compare the id:

if held_item == minecraft:lava_bucket use 6 1 4
if held_item id == value_of(page_contents get_line 0) use 6 1 4

Vec Pos

A floating-point position. Produced by: pos center, ship pos, sublevel pos

Mapper Output Description
x Double X component
y Double Y component
z Double Z component
distance_to <coords> Double Distance to the given position
direction_to <coords> Vec Dir Normalized direction vector toward the given position
rounded_down BlockPos Rounds each component down to get a block position

Examples:

if ship pos distance_to 0 0 0 > 100 set_redstone 15

Vec Box

A size vector (width, height, depth). Produced by: ship bounding_box, sublevel bounding_box

Mapper Output Description
x Double Width
y Double Height
z Double Depth
volume Double Total volume (x × y × z)

Vec Dir

A direction vector. Produced by: vec_pos direction_to, ship world_vel, ship local_vel, ship dir, sublevel world_vel, sublevel local_vel, sublevel dir, vec_dir normalize, vec_dir cross

Mapper Output Description
x Double X component
y Double Y component
z Double Z component
length Double Magnitude of the vector
normalize Vec Dir Unit vector in the same direction
cross <direction> Vec Dir Cross product with another direction
dot <direction> Double Dot product with another direction

Int

Produced by: pos x/y/z, redstone, page_number, double rounded_down/rounded_up, ship id, dimension index, string as_int

Mapper Output Description
== <int> Boolean Equality
> <int> Boolean Greater than
< <int> Boolean Less than
+ <int> Int Addition
- <int> Int Subtraction
% <int> Int Modulo
& <int> Int Bitwise AND
\| <int> Int Bitwise OR
<< <int> Int Left shift
>> <int> Int Right shift
* <double> Double Multiplication
/ <double> Double Division
as_string String Converts to string
as_char String The character with that code (65 as_char is A); a space for a code no character has

Examples:

if redstone > 7 set_redstone 15
set_redstone value_of(page_number - 1)
set_redstone value_of(pos x & 15)

Double

Produced by: pos x/y/z (Vec Pos), vec_dir length/dot, vec_box volume, int * / , ship mass

Mapper Output Description
== <double> Boolean Equality
> <double> Boolean Greater than
< <double> Boolean Less than
+ <double> Double Addition
- <double> Double Subtraction
* <double> Double Multiplication
/ <double> Double Division
rounded_down Int Floor
rounded_up Int Ceiling
as_string String Converts to string

String

Produced by: page_contents, script_contents, pos as_string, dimension as_string, int as_string, int as_char, double as_string, boolean as_string, ship slug, sublevel name, sublevel id

Mapper Output Description
== <string> Boolean Equality
+ <string> String Concatenation
<+ <string> String Prepends the given string
lines Int Splits at line breaks and returns the number of lines
get_line <int> String Splits at line breaks and returns the line at that index, or "" if out of bounds
remove_line <int> String Splits at line breaks and removes the line at that index; unchanged if out of bounds
split <string> String Replaces every occurrence of the given delimiter with a line break
as_int Int Parse as integer
as_double Double Parse as double
as_block_pos BlockPos Parse as "x y z" format
as_boolean Boolean Parse "true" / "false" (case-insensitive)
as_dimension Dimension Treat as a dimension key

In a quoted string, write a line break as \n, a " as \" and a \ as \\. Escapes belong only to script text: a string’s value holds real line breaks, and getters, executors and variables pass them on unchanged.

Examples:

if page_contents == "open" set_redstone 15
write_page value_of(pos as_string)
write_page value_of(pos as_string <+ "Pos: ")
set_redstone value_of(page_contents lines)
write_page value_of(page_contents remove_line 1)
write_page value_of(page_contents split ", ")

Boolean

Produced by: any ==, >, < comparison, string as_boolean

Mapper Output Description
&& <boolean> Boolean Logical AND
\|\| <boolean> Boolean Logical OR
as_string String "true" or "false"

Examples:

if pos x > 0 && value_of(pos z > 0) set_redstone 15
if page_contents == "open" || value_of(redstone > 0) set_redstone 15
write_page value_of(redstone > 7 as_string)
if page_contents as_boolean set_redstone 15

Dimension

Produced by: dimension, string as_dimension

Mapper Output Description
== <dimension> Boolean True if equal to the given dimension
index Int A stable integer index for this dimension (consistent per server session)
as_string String The dimension’s resource location (e.g. minecraft:overworld)

Examples:

if dimension == minecraft:the_nether set_redstone 15
set_redstone value_of(dimension index & 15)