constructor( dirNode = positionWorldDirection ) {

		super( 'vec2' );

		/**
		 * A direction vector for sampling why is by default `positionWorldDirection`.
		 *
		 * @type {Node<vec3>}
		 */
		this.dirNode = dirNode;

	}
Constructs a new equirect uv node.

@param {Node<vec3>} [dirNode=positionWorldDirection] - A direction vector for sampling which is by default `positionWorldDirection`.