kite3d/io.github.yuroyami.kite3d.math/Matrix4

Matrix4

Represents a 4x4 matrix.

The most common use of a 4x4 matrix in 3D computer graphics is as a transformation matrix: translation, rotation, shear, scale, reflection, or an orthographic or perspective projection. You apply it to a vector by multiplication.

Row-major and column-major ordering: set takes its arguments in row-major order, so a literal in source reads the way you would write the matrix on paper. The values are stored in elements in column-major order. There is no element constructor; use Matrix4().set(...).

Matrices are mutable and not thread-safe; confine an instance (and any object graph holding it) to a single thread, exactly as in three.js. Most methods mutate this and return it for chaining.

Constructors

Matrix4

constructor()

Properties

elements

val elements: DoubleArray

A column-major list of matrix values. Initialized to the 4x4 identity.

Functions

clone

fun clone(): Matrix4

Returns a new matrix with copied values from this instance.

compose

fun compose(position: Vector3, quaternion: Quaternion, scale: Vector3): Matrix4

Sets this matrix to the transformation composed of the given position, rotation (quaternion) and scale.

copy

fun copy(m: Matrix4): Matrix4

Copies the values of the given matrix m to this instance.

copyPosition

fun copyPosition(m: Matrix4): Matrix4

Copies the translation component of the given matrix m into this matrix's translation component.

decompose

fun decompose(position: Vector3, quaternion: Quaternion, scale: Vector3): Matrix4

Decomposes this matrix into its position, rotation (quaternion) and scale components and stores the result in the given objects.

determinant

fun determinant(): Double

Computes and returns the determinant of this matrix.

determinantAffine

fun determinantAffine(): Double

Computes and returns the determinant of this matrix assuming it is affine, saving some computations.

equals

open operator override fun equals(other: Any?): Boolean

Structural equality: true when other is a Matrix4 whose elements are element-wise equal (via DoubleArray.contentEquals, so NaN != NaN).

extractBasis

fun extractBasis(xAxis: Vector3, yAxis: Vector3, zAxis: Vector3): Matrix4

Extracts the basis of this matrix into the three axis vectors provided.

extractRotation

fun extractRotation(m: Matrix4): Matrix4

Extracts the rotation component of the given matrix m into this matrix's rotation component.

fromArray

fun fromArray(array: DoubleArray, offset: Int = 0): Matrix4

Sets the elements of the matrix from the given array (column-major order).

getMaxScaleOnAxis

fun getMaxScaleOnAxis(): Double

Returns the maximum scale value of the three axes.

hashCode

open override fun hashCode(): Int

identity

fun identity(): Matrix4

Sets this matrix to the 4x4 identity matrix.

invert

fun invert(): Matrix4

Inverts this matrix, using the analytic method. You can not invert a matrix with a determinant of zero; if you attempt this, the method produces a zero matrix instead.

lookAt

fun lookAt(eye: Vector3, target: Vector3, up: Vector3): Matrix4

Sets the rotation component of the transformation matrix, looking from eye towards target, oriented by the up direction.

makeBasis

fun makeBasis(xAxis: Vector3, yAxis: Vector3, zAxis: Vector3): Matrix4

Sets the given basis vectors as the columns of this matrix.

makeOrthographic

fun makeOrthographic(left: Double, right: Double, top: Double, bottom: Double, near: Double, far: Double, coordinateSystem: CoordinateSystem = CoordinateSystem.WebGL, reversedDepth: Boolean = false): Matrix4

Creates an orthographic projection matrix. Used internally by OrthographicCamera.updateProjectionMatrix.

makePerspective

fun makePerspective(left: Double, right: Double, top: Double, bottom: Double, near: Double, far: Double, coordinateSystem: CoordinateSystem = CoordinateSystem.WebGL, reversedDepth: Boolean = false): Matrix4

Creates a perspective projection matrix. Used internally by PerspectiveCamera.updateProjectionMatrix.

makeRotationAxis

fun makeRotationAxis(axis: Vector3, angle: Double): Matrix4

Sets this matrix as a rotational transformation around the given axis by the given angle angle (in radians).

makeRotationFromEuler

fun makeRotationFromEuler(euler: Euler): Matrix4

Sets the rotation component (the upper-left 3x3 matrix) of this matrix to the rotation specified by the given Euler angles euler. The rest of the matrix is set to the identity. Depending on the Euler.order, there are six possible outcomes.

makeRotationFromQuaternion

fun makeRotationFromQuaternion(q: Quaternion): Matrix4

Sets the rotation component of this matrix to the rotation specified by the given Quaternion q. The rest of the matrix is set to the identity.

makeRotationX

fun makeRotationX(theta: Double): Matrix4

Sets this matrix as a rotational transformation around the X axis by the given angle theta (in radians).

makeRotationY

fun makeRotationY(theta: Double): Matrix4

Sets this matrix as a rotational transformation around the Y axis by the given angle theta (in radians).

makeRotationZ

fun makeRotationZ(theta: Double): Matrix4

Sets this matrix as a rotational transformation around the Z axis by the given angle theta (in radians).

makeScale

fun makeScale(x: Double, y: Double, z: Double): Matrix4

Sets this matrix as a scale transformation.

makeShear

fun makeShear(xy: Double, xz: Double, yx: Double, yz: Double, zx: Double, zy: Double): Matrix4

Sets this matrix as a shear transformation.

makeTranslation

fun makeTranslation(v: Vector3): Matrix4

Sets this matrix as a translation transform from the given vector v.

fun makeTranslation(x: Double, y: Double, z: Double): Matrix4

Sets this matrix as a translation transform.

multiply

fun multiply(m: Matrix4): Matrix4

Post-multiplies this matrix by the given 4x4 matrix m.

multiplyMatrices

fun multiplyMatrices(a: Matrix4, b: Matrix4): Matrix4

Multiplies the given 4x4 matrices a and b and stores the result in this matrix.

multiplyScalar

fun multiplyScalar(s: Double): Matrix4

Multiplies every component of the matrix by the given scalar s.

premultiply

fun premultiply(m: Matrix4): Matrix4

Pre-multiplies this matrix by the given 4x4 matrix m.

scale

fun scale(v: Vector3): Matrix4

Multiplies the columns of this matrix by the given scale vector v.

set

fun set(n11: Double, n12: Double, n13: Double, n14: Double, n21: Double, n22: Double, n23: Double, n24: Double, n31: Double, n32: Double, n33: Double, n34: Double, n41: Double, n42: Double, n43: Double, n44: Double): Matrix4

Sets the elements of the matrix. The arguments are supposed to be in row-major order.

setFromMatrix3

fun setFromMatrix3(m: Matrix3): Matrix4

Sets the upper 3x3 elements of this matrix to the values of the given 3x3 matrix m.

setPosition

fun setPosition(v: Vector3): Matrix4

Sets the position component of this matrix from the given vector v, without affecting the rest of the matrix.

fun setPosition(x: Double, y: Double, z: Double): Matrix4

Sets the position component of this matrix from the given components, without affecting the rest of the matrix.

toArray

fun toArray(array: MutableList<Double> = mutableListOf(), offset: Int = 0): MutableList<Double>

Writes the elements of this matrix into array at offset (column-major order), growing the list as needed, and returns it.

toString

open override fun toString(): String

transpose

fun transpose(): Matrix4

Transposes this matrix in place.