setFromMatrixPosition( m ) {

		const e = m.elements;

		this.x = e[ 12 ];
		this.y = e[ 13 ];
		this.z = e[ 14 ];

		return this;

	}
Sets the vector components to the position elements of the
given transformation matrix.

@param {Matrix4} m - The 4x4 matrix.
@return {Vector3} A reference to this vector.