<!-- SOLUV · part 27 -->
ber} a - The rotation applied to the first axis, in radians.
	 * @param {number} b - The rotation applied to the second axis, in radians.
	 * @param {number} c - The rotation applied to the third axis, in radians.
	 * @param {('XYX'|'XZX'|'YXY'|'YZY'|'ZXZ'|'ZYZ')} order - A string specifying the axes order.
	 */
	setQuaternionFromProperEuler: setQuaternionFromProperEuler,
	/**
	 * Normalizes the given value according to the given typed array.
	 *
	 * @static
	 * @method
	 * @param {number} value - The float value in the range `[0,1]` to normalize.
	 * @param {TypedArray} array - The typed array that defines the data type of the value.
	 * @return {number} The normalize value.
	 */
	normalize: normalize,
	/**
	 * Denormalizes the given value according to the given typed array.
	 *
	 * @static
	 * @method
	 * @param {number} value - The value to denormalize.
	 * @param {TypedArray} array - The typed array that defines the data type of the value.
	 * @return {number} The denormalize (float) value in the range `[0,1]`.
	 */
	denormalize: denormalize
};

/**
 * Class representing a 2D vector. A 2D vector is an ordered pair of numbers
 * (labeled x and y), which can be used to represent a number of things, such as:
 *
 * - A point in 2D space (i.e. a position on a plane).
 * - A direction and length across a plane. In three.js the length will
 * always be the Euclidean distance(straight-line distance) from `(0, 0)` to `(x, y)`
 * and the direction is also measured from `(0, 0)` towards `(x, y)`.
 * - Any arbitrary ordered pair of numbers.
 *
 * There are other things a 2D vector can be used to represent, such as
 * momentum vectors, complex numbers and so on, however these are the most
 * common uses in three.js.
 *
 * Iterating through a vector instance will yield its components `(x, y)` in
 * the corresponding order.
 * ```js
 * const a = new THREE.Vector2( 0, 1 );
 *
 * //no arguments; will be initialised to (0, 0)
 * const b = new THREE.Vector2( );
 *
 * const d = a.distanceTo( b );
 * ```
 */
class Vector2 {

	static {

		/**
		 * This flag can be used for type testing.
		 *
		 * @type {boolean}
		 * @readonly
		 * @default true
		 */
		Vector2.prototype.isVector2 = true;

	}

	/**
	 * Constructs a new 2D vector.
	 *
	 * @param {number} [x=0] - The x value of this vector.
	 * @param {number} [y=0] - The y value of this vector.
	 */
	constructor( x = 0, y = 0 ) {

		/**
		 * The x value of this vector.
		 *
		 * @type {number}
		 */
		this.x = x;

		/**
		 * The y value of this vector.
		 *
		 * @type {number}
		 */
		this.y = y;

	}

	/**
	 * Alias for {@link Vector2#x}.
	 *
	 * @type {number}
	 */
	get width() {

		return this.x;

	}

	set width( value ) {

		this.x = value;

	}

	/**
	 * Alias for {@link Vector2#y}.
	 *
	 * @type {number}
	 */
	get height() {

		return this.y;

	}

	set height( value ) {

		this.y = value;

	}

	/**
	 * Sets the vector components.
	 *
	 * @param {number} x - The value of the x component.
	 * @param {number} y - The value of the y component.
	 * @return {Vector2} A reference to this vector.
	 */
	set( x, y ) {

		this.x = x;
		this.y = y;

		return this;

	}

	/**
	 * Sets the vector components to the same value.
	 *
	 * @param {number} scalar - The value to set for all vector components.
	 * @return {Vector2} A reference to this vector.
	 */
	setScalar( scalar ) {

		this.x = scalar;
		this.y = scalar;

		return this;

	}

	/**
	 * Sets the vector's x component to the given value
	 *
	 * @param {number} x - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setX( x ) {

		this.x = x;

		return this;

	}

	/**
	 * Sets the vector's y component to the given value
	 *
	 * @param {number} y - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setY( y ) {

		this.y = y;

		return this;

	}

	/**
	 * Allows to set a vector component with an index.
	 *
	 * @param {number} index - The component index. `0` equals to x, `1` equals to y.
	 * @param {number} value - The value to set.
	 * @return {Vector2} A reference to this vector.
	 */
	setComponent( index, value ) {

		switch ( index ) {

			case 0: this.x = value; break;
			case 1: this.y = value; break;
			default: throw new Error( 'THREE.Vector2: index is out of range: ' + index );

		}

		return this;

	}

	/**
	 * Returns the value of the vector component which matches the given index.
	 *
	 * @param {number} index - The component index. `0` equals to x, `1` equals to y.
	 * @return {number} A vector component value.
	 */
	getComponent( index ) {

		switch ( index ) {

			case 0: return this.x;
			case 1: return this.y;
			default: throw new Error( 'THREE.Vector2: index is out of range: ' + index );

		}

	}

	/**
	 * Returns a new vector with copied values from this instance.
	 *
	 * @return {Vector2} A clone of this instance.
	 */
	clone() {

		return new this.constructor( this.x, this.y );

	}

	/**
	 * Copies the values of the given vector to this in