<!-- SOLUV · part 36 -->
eturn {Vector3} A reference to this vector.
	 */
	addVectors( a, b ) {

		this.x = a.x + b.x;
		this.y = a.y + b.y;
		this.z = a.z + b.z;

		return this;

	}

	/**
	 * Adds the given vector scaled by the given factor to this instance.
	 *
	 * @param {Vector3|Vector4} v - The vector.
	 * @param {number} s - The factor that scales `v`.
	 * @return {Vector3} A reference to this vector.
	 */
	addScaledVector( v, s ) {

		this.x += v.x * s;
		this.y += v.y * s;
		this.z += v.z * s;

		return this;

	}

	/**
	 * Subtracts the given vector from this instance.
	 *
	 * @param {Vector3} v - The vector to subtract.
	 * @return {Vector3} A reference to this vector.
	 */
	sub( v ) {

		this.x -= v.x;
		this.y -= v.y;
		this.z -= v.z;

		return this;

	}

	/**
	 * Subtracts the given scalar value from all components of this instance.
	 *
	 * @param {number} s - The scalar to subtract.
	 * @return {Vector3} A reference to this vector.
	 */
	subScalar( s ) {

		this.x -= s;
		this.y -= s;
		this.z -= s;

		return this;

	}

	/**
	 * Subtracts the given vectors and stores the result in this instance.
	 *
	 * @param {Vector3} a - The first vector.
	 * @param {Vector3} b - The second vector.
	 * @return {Vector3} A reference to this vector.
	 */
	subVectors( a, b ) {

		this.x = a.x - b.x;
		this.y = a.y - b.y;
		this.z = a.z - b.z;

		return this;

	}

	/**
	 * Multiplies the given vector with this instance.
	 *
	 * @param {Vector3} v - The vector to multiply.
	 * @return {Vector3} A reference to this vector.
	 */
	multiply( v ) {

		this.x *= v.x;
		this.y *= v.y;
		this.z *= v.z;

		return this;

	}

	/**
	 * Multiplies the given scalar value with all components of this instance.
	 *
	 * @param {number} scalar - The scalar to multiply.
	 * @return {Vector3} A reference to this vector.
	 */
	multiplyScalar( scalar ) {

		this.x *= scalar;
		this.y *= scalar;
		this.z *= scalar;

		return this;

	}

	/**
	 * Multiplies the given vectors and stores the result in this instance.
	 *
	 * @param {Vector3} a - The first vector.
	 * @param {Vector3} b - The second vector.
	 * @return {Vector3} A reference to this vector.
	 */
	multiplyVectors( a, b ) {

		this.x = a.x * b.x;
		this.y = a.y * b.y;
		this.z = a.z * b.z;

		return this;

	}

	/**
	 * Applies the given Euler rotation to this vector.
	 *
	 * @param {Euler} euler - The Euler angles.
	 * @return {Vector3} A reference to this vector.
	 */
	applyEuler( euler ) {

		return this.applyQuaternion( _quaternion$5.setFromEuler( euler ) );

	}

	/**
	 * Applies a rotation specified by an axis and an angle to this vector.
	 *
	 * @param {Vector3} axis - A normalized vector representing the rotation axis.
	 * @param {number} angle - The angle in radians.
	 * @return {Vector3} A reference to this vector.
	 */
	applyAxisAngle( axis, angle ) {

		return this.applyQuaternion( _quaternion$5.setFromAxisAngle( axis, angle ) );

	}

	/**
	 * Multiplies this vector with the given 3x3 matrix.
	 *
	 * @param {Matrix3} m - The 3x3 matrix.
	 * @return {Vector3} A reference to this vector.
	 */
	applyMatrix3( m ) {

		const x = this.x, y = this.y, z = this.z;
		const e = m.elements;

		this.x = e[ 0 ] * x + e[ 3 ] * y + e[ 6 ] * z;
		this.y = e[ 1 ] * x + e[ 4 ] * y + e[ 7 ] * z;
		this.z = e[ 2 ] * x + e[ 5 ] * y + e[ 8 ] * z;

		return this;

	}

	/**
	 * Multiplies this vector by the given normal matrix and normalizes
	 * the result.
	 *
	 * @param {Matrix3} m - The normal matrix.
	 * @return {Vector3} A reference to this vector.
	 */
	applyNormalMatrix( m ) {

		return this.applyMatrix3( m ).normalize();

	}

	/**
	 * Multiplies this vector (with an implicit 1 in the 4th dimension) by m, and
	 * divides by perspective.
	 *
	 * @param {Matrix4} m - The matrix to apply.
	 * @return {Vector3} A reference to this vector.
	 */
	applyMatrix4( m ) {

		const x = this.x, y = this.y, z = this.z;
		const e = m.elements;

		const w = 1 / ( e[ 3 ] * x + e[ 7 ] * y + e[ 11 ] * z + e[ 15 ] );

		this.x = ( e[ 0 ] * x + e[ 4 ] * y + e[ 8 ] * z + e[ 12 ] ) * w;
		this.y = ( e[ 1 ] * x + e[ 5 ] * y + e[ 9 ] * z + e[ 13 ] ) * w;
		this.z = ( e[ 2 ] * x + e[ 6 ] * y + e[ 10 ] * z + e[ 14 ] ) * w;

		return this;

	}

	/**
	 * Applies the given Quaternion to this vector.
	 *
	 * @param {Quaternion} q - The Quaternion.
	 * @return {Vector3} A reference to this vector.
	 */
	applyQuaternion( q ) {

		// quaternion q is assumed to have unit length

		const vx = this.x, vy = this.y, vz = this.z;
		const qx = q.x, qy = q.y, qz = q.z, qw = q.w;

		// t = 2 * cross( q.xyz, v );
		const tx = 2 * ( qy * vz - qz * vy );
		const ty = 2 * ( qz * vx - qx * vz );
		const tz = 2 * ( qx * vy - qy * vx );

		// v + q.w * t + cross( q.xyz, t );
		this.x = vx + qw * tx + qy * tz - qz * ty;
		this.y = vy + qw * ty + qz * tx - qx * tz;
		this.z = vz + qw * tz + qx * ty - qy * tx;

		return this;

	}

	/**
	 * Projects this vector from world space into the camera's normalized
	 * device coordinate (NDC) spa