@web-engine-dev/math

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@web-engine-dev/math / Mat3

Class: Mat3

A 3x3 matrix stored in column-major order. Immutable by design - all operations return new instances.

Memory layout (column-major): | m0 m3 m6 | | m1 m4 m7 | | m2 m5 m8 |

Column vectors: [m0,m1,m2], [m3,m4,m5], [m6,m7,m8]

Example

// 2D rotation and translation
const rotation = Mat3.rotation(Math.PI / 4);  // 45 degrees
const translation = Mat3.translation(10, 20);
const combined = translation.mulMat(rotation);
const transformed = combined.mulVec2Point(point);

Constructors

Constructor

new Mat3(data?): Mat3

Parameters

data?

ArrayLike<number>

Returns

Mat3

Methods

add()

add(m): Mat3

Parameters

m

Mat3

Returns

Mat3

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copyMut()

copyMut(other): this

Copies another matrix into this matrix.

Parameters

other

Mat3

Source matrix

Returns

this

this for chaining

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copyToArray()

copyToArray(arr, offset?): void

Parameters

arr

number[] | Float32Array<ArrayBufferLike>

offset?

number = 0

Returns

void

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determinant()

determinant(): number

Returns

number

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equals()

equals(m, epsilon?): boolean

Parameters

m

Mat3

epsilon?

number = 0

Returns

boolean

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get()

get(row, col): number

Parameters

row

number

col

number

Returns

number

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getColumn()

getColumn(col): Vec3

Parameters

col

number

Returns

Vec3

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getRotationScale()

getRotationScale(): Mat3

Extract the upper-left 2x2 scale/rotation part.

Returns

Mat3

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getRow()

getRow(row): Vec3

Parameters

row

number

Returns

Vec3

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invert()

invert(): Mat3 | null

Returns

Mat3 | null

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invertMut()

invertMut(): Mat3 | null

Inverts this matrix in place.

Returns

Mat3 | null

this for chaining, or null if matrix is singular

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mul()

mul(s): Mat3

Parameters

s

number

Returns

Mat3

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mulMat()

mulMat(m): Mat3

Matrix-matrix multiplication (this * m).

Parameters

m

Mat3

Returns

Mat3

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mulVec2Direction()

mulVec2Direction(v): Vec2

Transform a Vec2 as a direction (z=0).

Parameters

v

Vec2

Returns

Vec2

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mulVec2Point()

mulVec2Point(v): Vec2

Transform a Vec2 as a point (z=1) and divide by resulting z. Returns a large vector if w is near zero to avoid Infinity/NaN.

Parameters

v

Vec2

Returns

Vec2

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mulVec3()

mulVec3(v): Vec3

Transform a Vec3 by this matrix.

Parameters

v

Vec3

Returns

Vec3

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setFromArrayMut()

setFromArrayMut(arr, offset?): this

Sets this matrix from an array (column-major order).

Parameters

arr

ArrayLike<number>

Source array

offset?

number = 0

Start offset in array

Returns

this

this for chaining

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setIdentityMut()

setIdentityMut(): this

Sets this matrix to the identity matrix.

Returns

this

this for chaining

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setMut()

setMut(m0, m1, m2, m3, m4, m5, m6, m7, m8): this

Sets all 9 elements of this matrix directly (column-major order).

Parameters

m0

number

Column 0, row 0

m1

number

Column 0, row 1

m2

number

Column 0, row 2

m3

number

Column 1, row 0

m4

number

Column 1, row 1

m5

number

Column 1, row 2

m6

number

Column 2, row 0

m7

number

Column 2, row 1

m8

number

Column 2, row 2

Returns

this

this for chaining

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sub()

sub(m): Mat3

Parameters

m

Mat3

Returns

Mat3

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toArray()

toArray(): number[]

Returns

number[]

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toFloat32Array()

toFloat32Array(): Float32Array

Returns

Float32Array

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toString()

toString(): string

Returns

string

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transpose()

transpose(): Mat3

Returns

Mat3

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transposeMut()

transposeMut(): this

Transposes this matrix in place.

Returns

this

this for chaining

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fromArray()

static fromArray(arr, offset?): Mat3

Parameters

arr

ArrayLike<number>

offset?

number = 0

Returns

Mat3

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fromColumns()

static fromColumns(c0, c1, c2): Mat3

Parameters

c0

Vec3

c1

Vec3

c2

Vec3

Returns

Mat3

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fromRows()

static fromRows(r0, r1, r2): Mat3

Parameters

r0

Vec3

r1

Vec3

r2

Vec3

Returns

Mat3

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identity()

static identity(): Mat3

Returns

Mat3

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rotation()

static rotation(angle): Mat3

Creates a 2D rotation matrix (rotation around Z).

Parameters

angle

number

Rotation angle in radians.

Returns

Mat3

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scaling()

static scaling(sx, sy): Mat3

Creates a 2D scale matrix.

Parameters

sx

number

sy

number

Returns

Mat3

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translation()

static translation(tx, ty): Mat3

Creates a 2D translation matrix.

Parameters

tx

number

ty

number

Returns

Mat3

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zero()

static zero(): Mat3

Returns

Mat3