Struct Delta

pub struct Delta {
    pub dx: i32,
    pub dy: i32,
}

Delta

A Delta represents a signed 2D offset — a difference in position, movement, or translation across a grid.

It is typically used to describe relative shifts between Coordinates, direction-based motion, or area translation.

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Example

use rpgx::prelude::*;

let d1 = Delta::new(3, -2);
let d2 = Delta::new(-1, 1);
let combined = d1 + d2; // Delta { dx: 2, dy: -1 }

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Fields

dx: i32

The horizontal delta (positive is rightward, negative is leftward).

dy: i32

The vertical delta (positive is downward, negative is upward).

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Constructors

Delta::new(dx: i32, dy: i32) -> Self

Creates a new delta with the specified components.

use rpgx::prelude::*;

let d = Delta::new(2, -1);

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Delta::zero() -> Self

Returns a delta representing no movement: (0, 0).

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Methods

fn invert(self) -> Self

Returns a new delta with inverted components (-dx, -dy).

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fn is_zero(self) -> bool

Returns true if both components are zero.

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fn manhattan(self) -> u32

Computes the Manhattan distance, i.e., the sum of absolute values of dx and dy.

use rpgx::prelude::*;

let d = Delta::new(-2, 3);
assert_eq!(d.manhattan(), 5);

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fn is_axis_aligned(self) -> bool

Returns true if the delta moves only in one direction (either horizontal or vertical).

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fn is_diagonal(self) -> bool

Returns true if both dx and dy are nonzero, i.e., the movement is diagonal.

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Design Notes

• Delta is signed and supports flexible offsetting in all directions.
• Used heavily in coordinate math, pathfinding, area translation, and movement logic.
• Use Coordinates::offseted() or try_offseted() to apply deltas to unsigned positions.

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See Also

• Coordinates: Grid position values.
• Shape: Region dimensions.
• Rect: Rectangular areas of the grid.
• Layer, Map Represents a 2D movement or directional offset with signed deltas.

Fields

dx: i32

dy: i32

Implementations

impl Delta

Constructors

pub fn new(dx: i32, dy: i32) -> Self

Creates a new delta with given x and y differences.

pub fn zero() -> Self

Returns a zero delta (no movement).

impl Delta

Utilities

pub fn invert(self) -> Self

Returns the inverse of the delta (negates both components).

pub fn is_zero(self) -> bool

Returns true if the delta is zero.

pub fn manhattan(self) -> u32

Returns the Manhattan distance represented by this delta.

pub fn is_axis_aligned(self) -> bool

Returns true if the delta moves in only one axis.

pub fn is_diagonal(self) -> bool

Returns true if this delta is diagonal (nonzero dx and dy).

Trait Implementations

impl Add<Delta> for Coordinates

fn add(self, delta: Delta) -> Self::Output

Adds a Delta, returning None if the result is negative.

type Output = Option<Coordinates>

The resulting type after applying the + operator.

impl Add<Delta> for Rect

type Output = Rect

The resulting type after applying the + operator.

fn add(self, delta: Delta) -> Self

Performs the + operation.

impl Add for Delta

type Output = Delta

The resulting type after applying the + operator.

fn add(self, rhs: Self) -> Self

Performs the + operation.

impl AddAssign for Delta

fn add_assign(&mut self, rhs: Self)

Performs the += operation.

impl Clone for Delta

fn clone(&self) -> Delta

Returns a duplicate of the value.

const fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Delta

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Delta

fn default() -> Delta

Returns the “default value” for a type.

impl Hash for Delta

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Neg for Delta

type Output = Delta

The resulting type after applying the - operator.

fn neg(self) -> Self::Output

Performs the unary - operation.

impl PartialEq for Delta

fn eq(&self, other: &Delta) -> bool

Tests for self and other values to be equal, and is used by ==.

const fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Sub<Delta> for Coordinates

fn sub(self, delta: Delta) -> Self::Output

Subtracts a Delta, returning None if the result is negative.

type Output = Option<Coordinates>

The resulting type after applying the - operator.

impl Sub<Delta> for Rect

type Output = Rect

The resulting type after applying the - operator.

fn sub(self, delta: Delta) -> Self

Performs the - operation.

impl Sub for Delta

type Output = Delta

The resulting type after applying the - operator.

fn sub(self, rhs: Self) -> Self

Performs the - operation.

impl SubAssign for Delta

fn sub_assign(&mut self, rhs: Self)

Performs the -= operation.

impl Copy for Delta

impl Eq for Delta

impl StructuralPartialEq for Delta