kite3d/io.github.yuroyami.kite3d.math/Quaternion

Quaternion

class Quaternion(x: Double = 0.0, y: Double = 0.0, z: Double = 0.0, w: Double = 1.0) : Iterable<Double>

A quaternion, used in three.js to represent rotations.

Iterating through an instance yields its components (x, y, z, w) in order.

three.js expects quaternions to be normalized.

Instances are mutable and not thread-safe; confine an instance (and any object graph holding it) to a single thread, exactly as in three.js.

Reading x/y/z/w has no side effect. Writing any of them, or calling a mutating method, fires the registered onChange callback (see that method).

Constructors

Quaternion

constructor(x: Double = 0.0, y: Double = 0.0, z: Double = 0.0, w: Double = 1.0)

Types

Companion

object Companion

Properties

var w: Double

The w value of this quaternion. Assigning fires the onChange callback.

var x: Double

The x value of this quaternion. Assigning fires the onChange callback.

var y: Double

The y value of this quaternion. Assigning fires the onChange callback.

var z: Double

The z value of this quaternion. Assigning fires the onChange callback.

Functions

angleTo

fun angleTo(q: Quaternion): Double

Returns the angle between this quaternion and q in radians.

clone

fun clone(): Quaternion

Returns a new quaternion with copied values from this instance.

conjugate

fun conjugate(): Quaternion

Returns the rotational conjugate of this quaternion: the same rotation in the opposite direction about the rotational axis.

copy

fun copy(quaternion: Quaternion): Quaternion

Copies the values of quaternion into this instance.

dot

fun dot(v: Quaternion): Double

Returns the dot product of this quaternion and v.

equals

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

Structural equality: true when other is a Quaternion with equal components (component-wise ==, so NaN != NaN).

fromArray

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

Sets this quaternion's components from array starting at offset.

fromBufferAttribute

fun fromBufferAttribute(attribute: AttributeLike, index: Int): Quaternion

Sets the components of this quaternion from attribute at index.

hashCode

open override fun hashCode(): Int

identity

fun identity(): Quaternion

Sets this quaternion to the identity quaternion (no rotation).

invert

fun invert(): Quaternion

Inverts this quaternion via conjugate. The quaternion is assumed to have unit length.

iterator

open operator override fun iterator(): Iterator<Double>

length

fun length(): Double

Returns the Euclidean length of this quaternion (as a 4D vector).

lengthSq

fun lengthSq(): Double

Returns the squared Euclidean length of this quaternion (as a 4D vector).

multiply

fun multiply(q: Quaternion): Quaternion

Multiplies this quaternion by q.

multiplyQuaternions

fun multiplyQuaternions(a: Quaternion, b: Quaternion): Quaternion

Multiplies a and b and stores the result in this instance.

normalize

fun normalize(): Quaternion

Normalizes this quaternion. It computes the quaternion that performs the same rotation but has length 1. A zero-length quaternion becomes the identity.

onChange

fun onChange(callback: () -> Unit): Quaternion

Registers callback to run whenever this quaternion's state changes (via a component setter or a mutating method). Reads never fire it.

premultiply

fun premultiply(q: Quaternion): Quaternion

Pre-multiplies this quaternion by q.

random

fun random(): Quaternion

Sets this quaternion to a uniformly random, normalized quaternion.

rotateTowards

fun rotateTowards(q: Quaternion, step: Double): Quaternion

Rotates this quaternion by an angular step (in radians) toward q, without overshooting it.

set

fun set(x: Double, y: Double, z: Double, w: Double): Quaternion

Sets the quaternion components.

setFromAxisAngle

fun setFromAxisAngle(axis: Vector3, angle: Double): Quaternion

Sets this quaternion from the given axis and angle.

setFromEuler

fun setFromEuler(euler: Euler, update: Boolean = true): Quaternion

Sets this quaternion from the rotation specified by the given Euler angles.

setFromRotationMatrix

fun setFromRotationMatrix(m: Matrix4): Quaternion

Sets this quaternion from the given rotation matrix m (the upper 3x3 of which must be an unscaled rotation).

setFromUnitVectors

fun setFromUnitVectors(vFrom: Vector3, vTo: Vector3): Quaternion

Sets this quaternion to the rotation required to rotate the direction vector vFrom to the direction vector vTo. Both are assumed normalized.

slerp

fun slerp(qb: Quaternion, t: Double): Quaternion

Performs a spherical linear interpolation between this quaternion and qb by factor t. Values in [0, 1] interpolate; values outside extrapolate.

slerpQuaternions

fun slerpQuaternions(qa: Quaternion, qb: Quaternion, t: Double): Quaternion

Performs a spherical linear interpolation between qa and qb and stores the result in this quaternion.

toArray

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

Writes the components of this quaternion into array at offset, growing the list as needed, and returns it.

toJSON

fun toJSON(): MutableList<Double>

Serialization result: the components of this quaternion as [x, y, z, w].

toString

open override fun toString(): String