Enum gridly::prelude::Direction

pub enum Direction {
    Up,
    Right,
    Down,
    Left,
}

The four cardinal directions: Up, Down, Left, and Right. Direction implements a number of simple helper methods. It also implements VectorLike, which allows it to be used in contexts where a Vector can be used as a unit vector in the given direction (for example, with Vector arithmetic).

Variants

Up

The negative row direction

Right

The positive column direction

Down

The positive row direction

Left

The negative column direction

Implementations

impl Direction

#[must_use]pub fn from_name(name: &str) -> Option<Self>

Parse a direction name into a direction. Currently supported names are (case insensitive):

• Up: Up, North, U, N
• Down: Down, South, D, S
• Left: Left, West, L, W
• Right: Right, East, R, E

Example

use gridly::prelude::*;

assert_eq!(Direction::from_name("up"), Some(Up));
assert_eq!(Direction::from_name("West"), Some(Left));
assert_eq!(Direction::from_name("Foo"), None);

#[must_use]pub fn sized_vec(self, length: isize) -> Vector

Return a vector with the given length in this direction

Example:

use gridly::prelude::*;

assert_eq!(Up.sized_vec(2), Vector::new(-2, 0));
assert_eq!(Down.sized_vec(3), Vector::new(3, 0));
assert_eq!(Left.sized_vec(1), Vector::new(0, -1));
assert_eq!(Right.sized_vec(5), Vector::new(0, 5));

#[must_use]pub fn unit_vec(self) -> Vector

Return the unit vector in the given direction.

Example:

use gridly::prelude::*;

assert_eq!(Up.unit_vec(), Vector::new(-1, 0));
assert_eq!(Down.unit_vec(), Vector::new(1, 0));
assert_eq!(Left.unit_vec(), Vector::new(0, -1));
assert_eq!(Right.unit_vec(), Vector::new(0, 1));

#[must_use]pub fn is_vertical(self) -> bool

True if this is Up or Down

Example:

use gridly::direction::*;

assert!(Up.is_vertical());
assert!(Down.is_vertical());
assert!(!Left.is_vertical());
assert!(!Right.is_vertical());

#[must_use]pub fn is_horizontal(self) -> bool

True if this is Left or Right

Example:

use gridly::direction::*;

assert!(!Up.is_horizontal());
assert!(!Down.is_horizontal());
assert!(Left.is_horizontal());
assert!(Right.is_horizontal());

#[must_use]pub fn reverse(self) -> Direction

Reverse this direction (Up → Down, etc)

use gridly::direction::*;

assert_eq!(Up.reverse(), Down);
assert_eq!(Down.reverse(), Up);
assert_eq!(Left.reverse(), Right);
assert_eq!(Right.reverse(), Left);

#[must_use]pub fn clockwise(self) -> Direction

Rotate this direction clockwise

Example:

use gridly::direction::*;

assert_eq!(Up.clockwise(), Right);
assert_eq!(Down.clockwise(), Left);
assert_eq!(Left.clockwise(), Up);
assert_eq!(Right.clockwise(), Down);

#[must_use]pub fn anticlockwise(self) -> Direction

Rotate this direction counterclockwise

Example:

use gridly::direction::*;

assert_eq!(Up.anticlockwise(), Left);
assert_eq!(Down.anticlockwise(), Right);
assert_eq!(Left.anticlockwise(), Down);
assert_eq!(Right.anticlockwise(), Up);

#[must_use]pub fn rotate(self, rotation: Rotation) -> Direction

Rotate this direction by the given rotation.

Example

use gridly::rotation::*;
use gridly::direction::*;

assert_eq!(Up.rotate(Clockwise), Right);
assert_eq!(Down.rotate(Rotation::None), Down);
assert_eq!(Left.rotate(Anticlockwise), Down);
assert_eq!(Right.rotate(Rotation::Flip), Left);

#[must_use]pub fn rotation_to(self, target: Direction) -> Rotation

Given a target direction, get the rotation that rotates this direction to that one.

Example

use gridly::direction::*;
use gridly::rotation::*;

assert_eq!(Up.rotation_to(Right), Clockwise);
assert_eq!(Down.rotation_to(Up), Rotation::Flip);
assert_eq!(Left.rotation_to(Down), Anticlockwise);
assert_eq!(Up.rotation_to(Up), Rotation::None);

Trait Implementations

impl<T: VectorLike> Add<T> for Direction

Adding a Vector to a Direction is equivelent to adding it to a unit vector in the given direction. Note that, because Direction itself implements VectorLike, this means you can add together a sequence of directions to get a Vector.

Example:

use gridly::vector::Vector;
use gridly::direction::*;

let base = Vector::new(3, 4);

assert_eq!(Up + base, Vector::new(2, 4));
assert_eq!(Down + base, Vector::new(4, 4));
assert_eq!(Right + base, Vector::new(3, 5));
assert_eq!(Left + base, Vector::new(3, 3));

assert_eq!(Up + Right + Up + Up, Vector::new(-3, 1));

type Output = Vector

The resulting type after applying the + operator.

#[must_use]fn add(self, rhs: T) -> Vector

Performs the + operation.

impl Clone for Direction

fn clone(&self) -> Direction

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Copy for Direction

impl Debug for Direction

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

Formats the value using the given formatter.

impl Eq for Direction

impl Hash for Direction

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, 

Feeds a slice of this type into the given Hasher.

impl Mul<isize> for Direction

Multiplying a Direction by an isize produces a Vector of the given length in the given direction

Example:

use gridly::direction::*;
use gridly::vector::Vector;

assert_eq!(Up * 5, Vector::new(-5, 0));
assert_eq!(Down * 3, Vector::new(3, 0));
assert_eq!(Left * 2, Vector::new(0, -2));
assert_eq!(Right * 4, Vector::new(0, 4));

type Output = Vector

The resulting type after applying the * operator.

#[must_use]fn mul(self, amount: isize) -> Vector

Performs the * operation.

impl Neg for Direction

Negating a Direction reverses it

Example:

use gridly::direction::*;

assert_eq!(-Up, Down);
assert_eq!(-Down, Up);
assert_eq!(-Left, Right);
assert_eq!(-Right, Left);

type Output = Direction

The resulting type after applying the - operator.

#[must_use]fn neg(self) -> Direction

Performs the unary - operation.

impl PartialEq<Direction> for Direction

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use]fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl StructuralEq for Direction

impl StructuralPartialEq for Direction

impl<T: VectorLike> Sub<T> for Direction

Subtracting a Vector from a Direction is equivelent to subtracing it from a unit vector in the given direction

Example:

use gridly::vector::Vector;
use gridly::direction::*;

let base = Vector::new(3, 3);

assert_eq!(Up - base, Vector::new(-4, -3));
assert_eq!(Down - base, Vector::new(-2, -3));
assert_eq!(Right - base, Vector::new(-3, -2));
assert_eq!(Left - base, Vector::new(-3, -4));

type Output = Vector

The resulting type after applying the - operator.

#[must_use]fn sub(self, rhs: T) -> Vector

Performs the - operation.

impl VectorLike for Direction

A Direction acts like a unit vector in the given direction. This allows it to be used in things like Vector arithmetic.

Example:

use gridly::prelude::*;

assert_eq!(Vector::new(1, 1) + Up, Vector::new(0, 1));
assert_eq!(Location::new(3, 4) - Left, Location::new(3, 5));

#[must_use]fn rows(&self) -> Rows

#[must_use]fn columns(&self) -> Columns

#[must_use]fn as_vector(&self) -> Vector

#[must_use]fn manhattan_length(&self) -> isize

Return the manhattan length of the vector. The manhattan length of a vector is the sum of the absolute values of its components.

#[must_use]fn checked_manhattan_length(&self) -> Option<isize>

Return the manhattan length of the vector, or None if there are any overflows.

#[must_use]fn clockwise(&self) -> Vector

Return a new vector, rotated 90 degrees clockwise.

#[must_use]fn anticlockwise(&self) -> Vector

Return a new vector, rotated 90 degrees counterclockwise.

#[must_use]fn reverse(&self) -> Vector

Return a new vector, facing the opposite direction of this one

#[must_use]fn transpose(&self) -> Vector

Swap the rows and columns of this Vector

#[must_use]fn direction(&self) -> Option<Direction>

If the vector is pointing in an orthogonal direction, return that direction

#[must_use]fn rotate(&self, rotation: Rotation) -> Vector

Return a new vector, rotated by a given rotation

#[must_use]fn get_component<T: Component>(&self) -> T

Generically get either the Rows or Columns of a vector