/**
 * Implementation of a quaternion.
 * Represents rotation in 3d space
 *
 * Iterating through a Quaternion instance will yield its components `(x, y, z, w)` in the corresponding order.
 * Note that a quaternion must be {@link normalize}d to properly represent rotation. Check documentation of individual operations when in doubt.
 *
 * Backed by a `Float64Array` of length 4, so instances are usable directly as typed-array views and indexed access `q[0]`..`q[3]` aliases `q.x`..`q.w`.
 *
 * @see https://en.wikipedia.org/wiki/Quaternion
 * @implements Iterable<number>
 *
 * @author Alex Goldring
 * @copyright Company Named Limited (c) 2026
 */
export class Quaternion extends Float64Array implements Iterable<number> {
    /**
     *
     * @param {Vector3} axis
     * @param {number} angle
     * @returns {Quaternion}
     */
    static fromAxisAngle(axis: Vector3, angle: number): Quaternion;
    /**
     * Create a randomly oriented quaternion
     * @param {function} [random] random number generator function
     * @returns {Quaternion}
     */
    static random(random?: Function): Quaternion;
    /**
     * Convenience constructor
     * Used XYZ angle order (see {@link fromEulerAnglesXYZ})
     * @param {number} x in radians
     * @param {number} y in radians
     * @param {number} z in radians
     * @returns {Quaternion}
     */
    static fromEulerAngles(x: number, y: number, z: number): Quaternion;
    /**
     * Behaves similarly to Unity's Quaternion `RotateToward` method
     * @param {Quaternion} result
     * @param {Quaternion} from
     * @param {Quaternion} to
     * @param {number} max_delta in radians
     */
    static rotateTowards(result: Quaternion, from: Quaternion, to: Quaternion, max_delta: number): void;
    /**
     * Ensure that built-in `TypedArray` methods (`map`, `slice`, `subarray`, ...) do not
     * try to construct a `Quaternion` via the buffer-form constructor.
     * @returns {Float64ArrayConstructor}
     */
    static get [Symbol.species](): Float64ArrayConstructor;
    /**
     *
     * @param {number} [x=0]
     * @param {number} [y=0]
     * @param {number} [z=0]
     * @param {number} [w=1]
     * @constructor
     */
    constructor(x?: number, y?: number, z?: number, w?: number);
    0: number;
    1: number;
    2: number;
    3: number;
    /**
     * Fires when the value of the quaternion changes
     * Signature of the signal data is as follows:
     *      (new_x, new_y, new_z, new_w, old_x, old_y, old_z, old_w)
     * @readonly
     * @type {Signal<number, number, number, number, number, number, number, number>}
     */
    readonly onChanged: Signal<number, number, number, number, number, number, number, number>;
    /**
     *
     * @param {number} v
     */
    set x(arg: number);
    /**
     *
     * @returns {number}
     */
    get x(): number;
    /**
     *
     * @param {number} v
     */
    set y(arg: number);
    /**
     *
     * @returns {number}
     */
    get y(): number;
    /**
     *
     * @param {number} v
     */
    set z(arg: number);
    /**
     *
     * @returns {number}
     */
    get z(): number;
    /**
     *
     * @param {number} v
     */
    set w(arg: number);
    /**
     *
     * @returns {number}
     */
    get w(): number;
    /**
     * Orient quaternion on a `forward` vector, with the spin matching `up` vector
     * Useful for `lookAt` operations, such as for camera or inverse kinematics.
     * Normalizes input, meaning input does not have to be normalized.
     *
     * NOTE: `forward` and `up` vectors being the same is allowed, but you will likely get unexpected rotation along the look axis, so prefer not to do it.
     *
     * @param {number} fx forward vector
     * @param {number} fy forward vector
     * @param {number} fz forward vector
     * @param {number} ux up vector
     * @param {number} uy up vector
     * @param {number} uz up vector
     * @returns {this}
     */
    _lookRotation(fx: number, fy: number, fz: number, ux: number, uy: number, uz: number): this;
    /**
     * Orient quaternion to align with the `forward` direction.
     * @param {Vector3} forward Does not need to be normalized.
     * @param {Vector3} [up=Vector3.up] Does not need to be normalized.
     * @returns {this}
     */
    lookRotation(forward: Vector3, up?: Vector3): this;
    /**
     * Vector dot product in 4 dimensions
     * @param {Quaternion} other
     * @return {number}
     */
    dot(other: Quaternion): number;
    /**
     * Makes this quaternion into an inverse of the other
     * @param {Quaternion} other
     * @returns {this}
     */
    copyInverse(other: Quaternion): this;
    /**
     * Calculates the inverse.
     * Correctly handles unnormalized quaternions.
     *
     * If your quaternion is normalized, you can use {@link conjugate} instead for speed.
     * @returns {this}
     * @see conjugate
     */
    invert(): this;
    /**
     * NOTE: this is the same as {@link invert} if the quaternion is normalized.
     * @returns {this}
     * @see invert
     */
    conjugate(): this;
    /**
     * Returns angle between this orientation and another
     * @param {Quaternion} other
     * @return {number} angle in radians
     */
    angleTo(other: Quaternion): number;
    /**
     * Set quaternion from axis + angle definition
     * @param {Vector3} axis
     * @param {number} angle
     * @returns {this}
     */
    fromAxisAngle(axis: Vector3, angle: number): this;
    /**
     *
     * @param {number} axis_x
     * @param {number} axis_y
     * @param {number} axis_z
     * @param {number} angle
     * @returns {this}
     */
    _fromAxisAngle(axis_x: number, axis_y: number, axis_z: number, angle: number): this;
    /**
     * Given a direction axis, compute rotation quaternions from current rotation to that axis as swing and twist. Swing moves to a given orientation while without "twisting",
     * `twist` just the twist around the given axis, no change in orientation.
     * @param {Vector3} axis
     * @param {Quaternion} swing Swing quaternion will be written here
     * @param {Quaternion} twist Twist quaternion will be written here
     * @returns {void}
     * @see slerp
     */
    computeSwingAndTwist(axis: Vector3, swing: Quaternion, twist: Quaternion): void;
    /**
     * Compute rotation (twist) around input axis
     * @param {Vector3} axis
     * @returns {number} in radians
     */
    computeTwistAngle(axis: Vector3): number;
    /**
     * Decompose quaternion to the axis of rotation and angle around this axis.
     * @param {Vector3} out_axis axis will be written here
     * @returns {number} angle in radians
     */
    toAxisAngle(out_axis: Vector3): number;
    /**
     * Normalize the quaternion in-place.
     * @returns {this}
     */
    normalize(): this;
    /**
     *
     * @param {number} val
     * @return {this}
     */
    multiplyScalar(val: number): this;
    /**
     * @param {Quaternion} other
     * @returns {this}
     */
    multiply(other: Quaternion): this;
    /**
     *
     * @param {Quaternion} first
     * @param {Quaternion} second
     * @returns {this}
     */
    multiplyQuaternions(first: Quaternion, second: Quaternion): this;
    /**
     *
     * @param {number} ax
     * @param {number} ay
     * @param {number} az
     * @param {number} aw
     * @param {number} bx
     * @param {number} by
     * @param {number} bz
     * @param {number} bw
     * @returns {this}
     */
    _multiplyQuaternions(ax: number, ay: number, az: number, aw: number, bx: number, by: number, bz: number, bw: number): this;
    /**
     *
     * @return {number}
     */
    length(): number;
    /**
     *
     * @param {Quaternion} other
     * @param {number} max_delta in radians
     * @returns {this}
     */
    rotateTowards(other: Quaternion, max_delta: number): this;
    /**
     *
     * @param {Vector3} source
     * @param {Vector3} target
     * @param {Vector3} [up]
     * @see lookRotation
     */
    lookAt(source: Vector3, target: Vector3, up?: Vector3): void;
    /**
     * @deprecated use {@link fromEulerAnglesXYZ} or others specifically.
     *
     * @param {number} x
     * @param {number} y
     * @param {number} z
     * @param {String} [order='XYZ'] a combination of capital letters X,Y,Z. Examples: XYZ, YXZ
     * @returns {this}
     *
     * @see fromEulerAnglesXYZ
     * @see fromEulerAnglesYXZ
     * @see fromEulerAnglesZXY
     * @see fromEulerAnglesZYX
     * @see fromEulerAnglesYZX
     * @see fromEulerAnglesXZY
     */
    __setFromEuler(x: number, y: number, z: number, order?: string): this;
    /**
     * @see https://localcoder.org/euler-angle-to-quaternion-then-quaternion-to-euler-angle
     * @see https://discourse.mcneel.com/t/what-is-the-right-method-to-convert-quaternion-to-plane-using-rhinocommon/92411/21?page=2
     * @param {Vector3} result
     */
    toEulerAnglesXYZ(result: Vector3): void;
    /**
     * Adapted from http://bediyap.com/programming/convert-quaternion-to-euler-rotations/
     * @param {Vector3} result
     */
    toEulerAnglesYXZ(result: Vector3): void;
    /**
     * Adapted from http://bediyap.com/programming/convert-quaternion-to-euler-rotations/
     * @param {Vector3} result
     */
    toEulerAnglesZYX(result: Vector3): void;
    /**
     * Set rotation from Euler angles in degrees.
     *
     * Order is explicitly XYZ.
     *
     * Utility shortcut, same as `fromEulerAnglesXYZ(x * π / 180, y * π / 180, z * π / 180)`
     *
     * @param {number} [x] angle in degrees
     * @param {number} [y] angle in degrees
     * @param {number} [z] angle in degrees
     * @returns {this}
     *
     * @see fromEulerAnglesXYZ
     */
    fromDegrees(x?: number, y?: number, z?: number): this;
    /**
     * XYZ order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesXYZ(x: number, y: number, z: number): this;
    /**
     * YXZ order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesYXZ(x: number, y: number, z: number): this;
    /**
     * ZXY order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesZXY(x: number, y: number, z: number): this;
    /**
     * ZYX order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesZYX(x: number, y: number, z: number): this;
    /**
     * YZX order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesYZX(x: number, y: number, z: number): this;
    /**
     * XZY order
     * @source: https://stackoverflow.com/questions/12088610/conversion-between-euler-quaternion-like-in-unity3d-engine
     * @see http://www.mathworks.com/matlabcentral/fileexchange/20696-function-to-convert-between-dcm-euler-angles-quaternions-and-euler-vectors/content/SpinCalc.m
     * @see https://github.com/mrdoob/three.js/blob/510705cde208b165fd87946b0f8504a1cd6dbe83/src/math/Quaternion.js#L206
     * @param {number} x angle in X axis in radians
     * @param {number} y angle in Y axis in radians
     * @param {number} z angle in Z axis in radians
     * @returns {this}
     */
    fromEulerAnglesXZY(x: number, y: number, z: number): this;
    /**
     * NOTE: Vectors need to be normalized
     *
     * @param {Vector3} from Must be normalized
     * @param {Vector3} to Must be normalized
     * @returns {this}
     */
    fromUnitVectors(from: Vector3, to: Vector3): this;
    /**
     * @param {number[]|Float32Array} m4x4
     * @returns {this}
     */
    setFromRotationMatrix(m4x4: number[] | Float32Array): this;
    /**
     * This algorithm comes from "Quaternion Calculus and Fast Animation",
     * Ken Shoemake, 1987 SIGGRAPH course notes
     * @see https://gitlab.com/libeigen/eigen/-/blob/master/Eigen/src/Geometry/Quaternion.h#L813
     * @param {number} m11
     * @param {number} m12
     * @param {number} m13
     * @param {number} m21
     * @param {number} m22
     * @param {number} m23
     * @param {number} m31
     * @param {number} m32
     * @param {number} m33
     * @returns {this}
     */
    __setFromRotationMatrix(m11: number, m12: number, m13: number, m21: number, m22: number, m23: number, m31: number, m32: number, m33: number): this;
    /**
     * Linear interpolation
     * @param {Quaternion} other
     * @param {number} t fractional value between 0 and 1
     * @returns {this}
     */
    lerp(other: Quaternion, t: number): this;
    /**
     * Linear interpolation of two quaternions
     * Pretty good, not as good as slerp, but close enough for most application
     * @param {Quaternion} first
     * @param {Quaternion} second
     * @param {number} t
     * @returns {this}
     */
    lerpQuaternions(first: Quaternion, second: Quaternion, t: number): this;
    /**
     * Spherical linear interpolation
     * @param {Quaternion} from
     * @param {Quaternion} to
     * @param {number} t coefficient, how much between the input quaternions? Must be a value between 0 and 1
     * @returns {this}
     */
    slerpQuaternions(from: Quaternion, to: Quaternion, t: number): this;
    /**
     * @see https://github.com/toji/gl-matrix/blob/master/src/gl-matrix/quat.js
     * @param {Quaternion} other
     * @param {number} t
     * @returns {this}
     */
    slerp(other: Quaternion, t: number): this;
    /**
     *
     * @param {function(x:number,y:number,z:number,w:number)} handler
     * @param {*} [thisArg]
     * @returns {this}
     */
    process(handler: any, thisArg?: any): this;
    /**
     *
     * @param {Quaternion} other
     * @returns {this}
     */
    copy(other: Quaternion): this;
    /**
     *
     * @returns {Quaternion}
     */
    clone(): Quaternion;
    /**
     * Set current value of the quaternion
     * You *MUST* use this method in order for {@link Quaternion#onChanged} signal to be fired
     * @param {number} x
     * @param {number} y
     * @param {number} z
     * @param {number} w
     * @returns {this}
     */
    set(x: number, y: number, z: number, w: number): this;
    toJSON(): {
        x: number;
        y: number;
        z: number;
        w: number;
    };
    /**
     *
     * @param obj
     * @return {this}
     */
    fromJSON(obj: any): this;
    /**
     *
     * @param {BinaryBuffer} buffer
     */
    toBinaryBuffer(buffer: BinaryBuffer): void;
    /**
     *
     * @param {BinaryBuffer} buffer
     */
    fromBinaryBuffer(buffer: BinaryBuffer): void;
    /**
     *
     * @param {BinaryBuffer} buffer
     */
    toBinaryBufferFloat32(buffer: BinaryBuffer): void;
    /**
     *
     * @param {BinaryBuffer} buffer
     */
    fromBinaryBufferFloat32(buffer: BinaryBuffer): void;
    /**
     *
     * @param {number[]} array
     * @param {number} [offset]
     * @returns {this}
     */
    fromArray(array: number[], offset?: number): this;
    /**
     *
     * @param {number[]} [array]
     * @param {number} [offset]
     * @returns {number[]}
     */
    toArray(array?: number[], offset?: number): number[];
    /**
     * Strict equality check
     * @param {Quaternion} other
     * @returns {boolean}
     * @see roughlyEquals
     */
    equals(other: Quaternion): boolean;
    /**
     *
     * @returns {number} integer hash
     */
    hash(): number;
    /**
     * Check for approximate equality between two quaternions
     * @param {Quaternion} other
     * @param {number} [tolerance]
     * @return {boolean}
     */
    roughlyEquals(other: Quaternion, tolerance?: number): boolean;
    /**
     *
     * @param {number} x
     * @param {number} y
     * @param {number} z
     * @param {number} w
     * @param {number} [tolerance] acceptable difference value per coordinate
     * @return {boolean}
     */
    _roughlyEquals(x: number, y: number, z: number, w: number, tolerance?: number): boolean;
    /**
     * @deprecated use {@link random} instead
     * @param {function():number} random
     */
    setRandom(random: () => number): void;
    /**
     * Randomly orient current quaternion
     * @param {function():number} [random=Math.random] Random number generator function.
     */
    random(random?: () => number): this;
    /**
     * @deprecated use `fromArray`
     */
    readFromArray: (array: number[], offset?: number) => this;
    /**
     * @deprecated use `toArray`
     */
    writeToArray: (array?: number[], offset?: number) => number[];
    /**
     * @deprecated use `toArray`
     */
    asArray: (array?: number[], offset?: number) => number[];
    fromEulerAngles: (x: number, y: number, z: number) => this;
    /**
     * Shortcut for type checking
     * @readonly
     * @type {boolean}
     */
    readonly isQuaternion: boolean;
}
export namespace Quaternion {
    let identity: Quaternion;
    let typeName: string;
}
export default Quaternion;
import Signal from "../events/signal/Signal.js";
import Vector3 from "./Vector3.js";
//# sourceMappingURL=Quaternion.d.ts.map