Class Vec2

A 2-dimensional vector. Vec2 is commonly used to represent 2D positions, directions, texture coordinates (UVs) or any pair of related numeric values.

Operations follow one convention throughout the math classes: a method that modifies the vector it is called on returns it, so calls can be chained and nothing is allocated, while queries such as distance and dot return a number. Two-operand forms such as add2 and sub2 write the result of lhs op rhs into this, and it is safe for this to also be one of the operands. Use clone for an independent copy and copy to overwrite one vector with another.

The static constants such as ZERO and UP are frozen shared instances: read them freely, but writing to one throws. Copy a constant before modifying it.

Example

// Scroll a texture offset each frame without allocating
const offset = new Vec2(0, 0);
const speed = new Vec2(0.1, 0);
offset.addScaled(speed, dt);

Example

// Chain mutating operations; each returns the vector it was called on
const toTarget = new Vec2().sub2(target, position).normalize();
const distance = target.distance(position);

Index

Constructors

constructor

Properties

x y DOWN HALF LEFT ONE RIGHT UP ZERO

Constructors

constructor

new Vec2(x?: number, y?: number): Vec2
Creates a new Vec2 instance.
Parameters
- Optionalx: number
  The x value. Defaults to 0.
- Optionaly: number
  The y value. Defaults to 0.
Returns Vec2
Example
```
const v1 = new Vec2(); // defaults to 0, 0
const v2 = new Vec2(1, 2);
```
- Defined in core/math/vec2.js:47
new Vec2(arr: number[]): Vec2
Creates a new Vec2 instance.
Parameters
- arr: number[]
  The array to set the vector values from.
Returns Vec2
Example
```
const v = new Vec2([1, 2]);
```
- Defined in core/math/vec2.js:47

Properties

x

x: number

The first component of the vector.

y

y: number

The second component of the vector.

`Static` `Readonly`DOWN

DOWN: Vec2 = ...

A constant vector set to [0, -1].

`Static` `Readonly`HALF

HALF: Vec2 = ...

A constant vector set to [0.5, 0.5].

`Static` `Readonly`LEFT

LEFT: Vec2 = ...

A constant vector set to [-1, 0].

`Static` `Readonly`ONE

ONE: Vec2 = ...

A constant vector set to [1, 1].

`Static` `Readonly`RIGHT

RIGHT: Vec2 = ...

A constant vector set to [1, 0].

`Static` `Readonly`UP

UP: Vec2 = ...

A constant vector set to [0, 1].

`Static` `Readonly`ZERO

ZERO: Vec2 = ...

A constant vector set to [0, 0].

Methods

add

add(rhs: Vec2): Vec2
Adds a 2-dimensional vector to another in place.
Parameters
- rhs: Vec2
  The vector to add to the specified vector.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(10, 10);
const b = new Vec2(20, 20);

a.add(b);

// Outputs [30, 30]
console.log("The result of the addition is: " + a.toString());
```
- Defined in core/math/vec2.js:91

add2

add2(lhs: Vec2, rhs: Vec2): Vec2
Adds two 2-dimensional vectors together and returns the result.
Parameters
- lhs: Vec2
  The first vector operand for the addition.
- rhs: Vec2
  The second vector operand for the addition.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(10, 10);
const b = new Vec2(20, 20);
const r = new Vec2();

r.add2(a, b);
// Outputs [30, 30]

console.log("The result of the addition is: " + r.toString());
```
- Defined in core/math/vec2.js:114

addScalar

addScalar(scalar: number): Vec2
Adds a number to each element of a vector.
Parameters
- scalar: number
  The number to add.
Returns Vec2
Self for chaining.
Example
```
const vec = new Vec2(3, 4);

vec.addScalar(2);

// Outputs [5, 6]
console.log("The result of the addition is: " + vec.toString());
```
- Defined in core/math/vec2.js:134

addScaled

addScaled(rhs: Vec2, scalar: number): Vec2
Adds a 2-dimensional vector scaled by scalar value. Does not modify the vector being added.
Parameters
- rhs: Vec2
  The vector to add to the specified vector.
- scalar: number
  The number to multiply the added vector with.
Returns Vec2
Self for chaining.
Example
```
const vec = new Vec2(1, 2);

vec.addScaled(Vec2.UP, 2);

// Outputs [1, 4]
console.log("The result of the addition is: " + vec.toString());
```
- Defined in core/math/vec2.js:155

angle

angle(): number
Returns the angle in degrees of the specified 2-dimensional vector.

Returns number
The angle in degrees of the specified 2-dimensional vector.
Example
```
const v = new Vec2(6, 0);
const angle = v.angle();
// Outputs 90..
console.log("The angle of the vector is: " + angle);
```
- Defined in core/math/vec2.js:544

angleTo

angleTo(rhs: Vec2): number
Returns the shortest Euler angle between two 2-dimensional vectors.
Parameters
- rhs: Vec2
  The 2-dimensional vector to calculate angle to.
Returns number
The shortest angle in degrees between two 2-dimensional vectors.
Example
```
const a = new Vec2(0, 10); // up
const b = new Vec2(1, -1); // down-right
const angle = a.angleTo(b);
// Outputs 135..
console.log("The angle between vectors a and b: " + angle);
```
- Defined in core/math/vec2.js:560

ceil

ceil(src?: Vec2): Vec2
Each element is rounded up to the next largest integer.
Parameters
- Optionalsrc: Vec2 = ...
  The vector to ceil. If not set, the operation is done in place.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2(1.2, 3.1);
v.ceil();
// v is now [2, 4]
```
- Defined in core/math/vec2.js:590

clone

clone(): Vec2
Returns an identical copy of the specified 2-dimensional vector.

Returns Vec2
A 2-dimensional vector containing the result of the cloning.
Example
```
const v = new Vec2(10, 20);
const vclone = v.clone();
console.log("The result of the cloning is: " + vclone.toString());
```
- Defined in core/math/vec2.js:171

copy

copy(rhs: Vec2): Vec2
Copies the contents of a source 2-dimensional vector to a destination 2-dimensional vector.
Parameters
- rhs: Vec2
  A vector to copy to the specified vector.
Returns Vec2
Self for chaining.
Example
```
const src = new Vec2(10, 20);
const dst = new Vec2();

dst.copy(src);

console.log("The two vectors are " + (dst.equals(src) ? "equal" : "different"));
```
- Defined in core/math/vec2.js:190

cross

cross(rhs: Vec2): number
Returns the result of a cross product operation performed on the two specified 2-dimensional vectors.
Parameters
- rhs: Vec2
  The second 2-dimensional vector operand of the cross product.
Returns number
The cross product of the two vectors.
Example
```
const right = new Vec2(1, 0);
const up = new Vec2(0, 1);
const crossProduct = right.cross(up);

// Prints 1
console.log("The result of the cross product is: " + crossProduct);
```
- Defined in core/math/vec2.js:211

distance

distance(rhs: Vec2): number
Returns the distance between the two specified 2-dimensional vectors.
Parameters
- rhs: Vec2
  The second 2-dimensional vector to test.
Returns number
The distance between the two vectors.
Example
```
const v1 = new Vec2(5, 10);
const v2 = new Vec2(10, 20);
const d = v1.distance(v2);
console.log("The distance between v1 and v2 is: " + d);
```
- Defined in core/math/vec2.js:226

distanceSq

distanceSq(rhs: Vec2): number
Returns the squared distance between the two specified 2-dimensional vectors.
Parameters
- rhs: Vec2
  The second 2-dimensional vector to test.
Returns number
The squared distance between the two vectors.
Example
```
const v1 = new Vec2(5, 10);
const v2 = new Vec2(10, 20);
const d = v1.distanceSq(v2);
console.log("The squared distance between v1 and v2 is: " + d);
```
- Defined in core/math/vec2.js:243

div

div(rhs: Vec2): Vec2
Divides a 2-dimensional vector by another in place.
Parameters
- rhs: Vec2
  The vector to divide the specified vector by.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(4, 9);
const b = new Vec2(2, 3);

a.div(b);

// Outputs [2, 3]
console.log("The result of the division is: " + a.toString());
```
- Defined in core/math/vec2.js:263

div2

div2(lhs: Vec2, rhs: Vec2): Vec2
Divides one 2-dimensional vector by another and writes the result to the specified vector.
Parameters
- lhs: Vec2
  The dividend vector (the vector being divided).
- rhs: Vec2
  The divisor vector (the vector dividing the dividend).
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(4, 9);
const b = new Vec2(2, 3);
const r = new Vec2();

r.div2(a, b);

// Outputs [2, 3]
console.log("The result of the division is: " + r.toString());
```
- Defined in core/math/vec2.js:286

divScalar

divScalar(scalar: number): Vec2
Divides each element of a vector by a number.
Parameters
- scalar: number
  The number to divide by.
Returns Vec2
Self for chaining.
Example
```
const vec = new Vec2(3, 6);

vec.divScalar(3);

// Outputs [1, 2]
console.log("The result of the division is: " + vec.toString());
```
- Defined in core/math/vec2.js:306

dot

dot(rhs: Vec2): number
Returns the result of a dot product operation performed on the two specified 2-dimensional vectors.
Parameters
- rhs: Vec2
  The second 2-dimensional vector operand of the dot product.
Returns number
The result of the dot product operation.
Example
```
const v1 = new Vec2(5, 10);
const v2 = new Vec2(10, 20);
const v1dotv2 = v1.dot(v2);
console.log("The result of the dot product is: " + v1dotv2);
```
- Defined in core/math/vec2.js:325

equals

equals(rhs: Vec2): boolean
Reports whether two vectors are equal.
Parameters
- rhs: Vec2
  The vector to compare to the specified vector.
Returns boolean
True if the vectors are equal and false otherwise.
Example
```
const a = new Vec2(1, 2);
const b = new Vec2(4, 5);
console.log("The two vectors are " + (a.equals(b) ? "equal" : "different"));
```
- Defined in core/math/vec2.js:339

equalsApprox

equalsApprox(rhs: Vec2, epsilon?: number): boolean
Reports whether two vectors are equal using an absolute error tolerance.
Parameters
- rhs: Vec2
  The vector to be compared against.
- Optionalepsilon: number = 1e-6
  The maximum difference between each component of the two vectors. Defaults to 1e-6.
Returns boolean
True if the vectors are equal and false otherwise.
Example
```
const a = new Vec2();
const b = new Vec2();
console.log("The two vectors are approximately " + (a.equalsApprox(b, 1e-9) ? "equal" : "different"));
```
- Defined in core/math/vec2.js:355

floor

floor(src?: Vec2): Vec2
Each element is set to the largest integer less than or equal to its value.
Parameters
- Optionalsrc: Vec2 = ...
  The vector to floor. If not set, the operation is done in place.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2(1.2, 3.9);
v.floor();
// v is now [1, 3]
```
- Defined in core/math/vec2.js:574

fromArray

fromArray(
arr: number[] | ArrayBufferView<ArrayBufferLike>,
offset?: number,
): Vec2
Set the values of the vector from an array.
Parameters
- arr: number[] | ArrayBufferView<ArrayBufferLike>
  The array to set the vector values from.
- Optionaloffset: number = 0
  The zero-based index at which to start copying elements from the array. Default is 0.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2();
v.fromArray([20, 10]);
// v is set to [20, 10]
```
- Defined in core/math/vec2.js:742

length

length(): number
Returns the magnitude of the specified 2-dimensional vector.

Returns number
The magnitude of the specified 2-dimensional vector.
Example
```
const vec = new Vec2(3, 4);
const len = vec.length();
// Outputs 5
console.log("The length of the vector is: " + len);
```
- Defined in core/math/vec2.js:370

lengthSq

lengthSq(): number
Returns the magnitude squared of the specified 2-dimensional vector.

Returns number
The magnitude squared of the specified 2-dimensional vector.
Example
```
const vec = new Vec2(3, 4);
const len = vec.lengthSq();
// Outputs 25
console.log("The length squared of the vector is: " + len);
```
- Defined in core/math/vec2.js:384

lerp

lerp(lhs: Vec2, rhs: Vec2, alpha: number): Vec2
Returns the result of a linear interpolation between two specified 2-dimensional vectors.
Parameters
- lhs: Vec2
  The 2-dimensional vector to interpolate from.
- rhs: Vec2
  The 2-dimensional vector to interpolate to.
- alpha: number
  The value controlling the point of interpolation. Between 0 and 1, the linear interpolant will occur on a straight line between lhs and rhs. Outside of this range, the linear interpolant will occur on a ray extrapolated from this line.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(0, 0);
const b = new Vec2(10, 10);
const r = new Vec2();

r.lerp(a, b, 0);   // r is equal to a
r.lerp(a, b, 0.5); // r is 5, 5
r.lerp(a, b, 1);   // r is equal to b
```
- Defined in core/math/vec2.js:406

max

max(rhs: Vec2): Vec2
Each element is assigned a value from rhs parameter if it is larger.
Parameters
- rhs: Vec2
  The 2-dimensional vector used as the source of elements to compare to.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(5, 1);
const b = new Vec2(2, 8);
a.max(b);
// a is now [5, 8]
```
- Defined in core/math/vec2.js:640

min

min(rhs: Vec2): Vec2
Each element is assigned a value from rhs parameter if it is smaller.
Parameters
- rhs: Vec2
  The 2-dimensional vector used as the source of elements to compare to.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(5, 1);
const b = new Vec2(2, 8);
a.min(b);
// a is now [2, 1]
```
- Defined in core/math/vec2.js:623

mul

mul(rhs: Vec2): Vec2
Multiplies a 2-dimensional vector to another in place.
Parameters
- rhs: Vec2
  The 2-dimensional vector used as the second multiplicand of the operation.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(2, 3);
const b = new Vec2(4, 5);

a.mul(b);

// Outputs 8, 15
console.log("The result of the multiplication is: " + a.toString());
```
- Defined in core/math/vec2.js:427

mul2

mul2(lhs: Vec2, rhs: Vec2): Vec2
Returns the result of multiplying the specified 2-dimensional vectors together.
Parameters
- lhs: Vec2
  The 2-dimensional vector used as the first multiplicand of the operation.
- rhs: Vec2
  The 2-dimensional vector used as the second multiplicand of the operation.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(2, 3);
const b = new Vec2(4, 5);
const r = new Vec2();

r.mul2(a, b);

// Outputs 8, 15
console.log("The result of the multiplication is: " + r.toString());
```
- Defined in core/math/vec2.js:450

mulScalar

mulScalar(scalar: number): Vec2
Multiplies each element of a vector by a number.
Parameters
- scalar: number
  The number to multiply by.
Returns Vec2
Self for chaining.
Example
```
const vec = new Vec2(3, 6);

vec.mulScalar(3);

// Outputs [9, 18]
console.log("The result of the multiplication is: " + vec.toString());
```
- Defined in core/math/vec2.js:470

normalize

normalize(src?: Vec2): Vec2
Returns this 2-dimensional vector converted to a unit vector in place. If the vector has a length of zero, the vector's elements will be set to zero.
Parameters
- Optionalsrc: Vec2 = ...
  The vector to normalize. If not set, the operation is done in place.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2(25, 0);

v.normalize();

// Outputs 1, 0
console.log("The result of the vector normalization is: " + v.toString());
```
- Defined in core/math/vec2.js:502

rotate

rotate(degrees: number): Vec2
Rotate a vector by an angle in degrees.
Parameters
- degrees: number
  The number to degrees to rotate the vector by.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2(0, 10);

v.rotate(45); // rotates by 45 degrees

// Outputs [7.071068.., 7.071068..]
console.log("Vector after rotation is: " + v.toString());
```
- Defined in core/math/vec2.js:526

round

round(src?: Vec2): Vec2
Each element is rounded up or down to the nearest integer.
Parameters
- Optionalsrc: Vec2 = ...
  The vector to round. If not set, the operation is done in place.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2(1.4, 3.6);
v.round();
// v is now [1, 4]
```
- Defined in core/math/vec2.js:606

set

set(x: number, y: number): Vec2
Sets the specified 2-dimensional vector to the supplied numerical values.
Parameters
- x: number
  The value to set on the first component of the vector.
- y: number
  The value to set on the second component of the vector.
Returns Vec2
Self for chaining.
Example
```
const v = new Vec2();
v.set(5, 10);

// Outputs 5, 10
console.log("The result of the vector set is: " + v.toString());
```
- Defined in core/math/vec2.js:659

sub

sub(rhs: Vec2): Vec2
Subtracts a 2-dimensional vector from another in place.
Parameters
- rhs: Vec2
  The vector to subtract from the specified vector.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(10, 10);
const b = new Vec2(20, 20);

a.sub(b);

// Outputs [-10, -10]
console.log("The result of the subtraction is: " + a.toString());
```
- Defined in core/math/vec2.js:680

sub2

sub2(lhs: Vec2, rhs: Vec2): Vec2
Subtracts two 2-dimensional vectors from one another and returns the result.
Parameters
- lhs: Vec2
  The first vector operand for the subtraction.
- rhs: Vec2
  The second vector operand for the subtraction.
Returns Vec2
Self for chaining.
Example
```
const a = new Vec2(10, 10);
const b = new Vec2(20, 20);
const r = new Vec2();

r.sub2(a, b);

// Outputs [-10, -10]
console.log("The result of the subtraction is: " + r.toString());
```
- Defined in core/math/vec2.js:703

subScalar

subScalar(scalar: number): Vec2
Subtracts a number from each element of a vector.
Parameters
- scalar: number
  The number to subtract.
Returns Vec2
Self for chaining.
Example
```
const vec = new Vec2(3, 4);

vec.subScalar(2);

// Outputs [1, 2]
console.log("The result of the subtraction is: " + vec.toString());
```
- Defined in core/math/vec2.js:723

toArray

toArray(arr?: number[], offset?: number): number[]
Parameters
- Optionalarr: number[]
  The array to populate with the vector's number components. If not specified, a new array is created.
- Optionaloffset: number
  The zero-based index at which to start copying elements to the array. Default is 0.
Returns number[]
The vector as an array.
- Defined in core/math/vec2.js:763
toArray(arr: ArrayBufferView, offset?: number): ArrayBufferView
Parameters
- arr: ArrayBufferView
  The array to populate with the vector's number components. If not specified, a new array is created.
- Optionaloffset: number
  The zero-based index at which to start copying elements to the array. Default is 0.
Returns ArrayBufferView
The vector as an array.
- Defined in core/math/vec2.js:771

toString

toString(): string
Converts the vector to string form.

Returns string
The vector in string form.
Example
```
const v = new Vec2(20, 10);
// Outputs [20, 10]
console.log(v.toString());
```
- Defined in core/math/vec2.js:758

Class Vec2

Example

Example

Index

Constructors

Properties

Methods

Constructors

constructor

Parameters

Returns Vec2

Example

Parameters

Returns Vec2

Example

Properties

x

y

Static ReadonlyDOWN

Static ReadonlyHALF

Static ReadonlyLEFT

Static ReadonlyONE

Static ReadonlyRIGHT

Static ReadonlyUP

Static ReadonlyZERO

Methods

add

Parameters

Returns Vec2

Example

add2

Parameters

Returns Vec2

Example

addScalar

Parameters

Returns Vec2

Example

addScaled

Parameters

Returns Vec2

Example

angle

Returns number

Example

angleTo

Parameters

Returns number

Example

ceil

Parameters

Returns Vec2

Example

clone

Returns Vec2

Example

copy

Parameters

Returns Vec2

Example

cross

Parameters

Returns number

Example

distance

Parameters

Returns number

Example

distanceSq

Parameters

Returns number

Example

div

Parameters

Returns Vec2

Example

div2

Parameters

Returns Vec2

Example

`Static` `Readonly`DOWN

`Static` `Readonly`HALF

`Static` `Readonly`LEFT

`Static` `Readonly`ONE

`Static` `Readonly`RIGHT

`Static` `Readonly`UP

`Static` `Readonly`ZERO