traverseVisible( callback ) {

		if ( this.visible === false ) return;

		callback( this );

		const children = this.children;

		for ( let i = 0, l = children.length; i < l; i ++ ) {

			children[ i ].traverseVisible( callback );

		}

	}
Like {@link Object3D#traverse}, but the callback will only be executed for visible 3D objects.
Descendants of invisible 3D objects are not traversed.

Note: Modifying the scene graph inside the callback is discouraged.

@param {Function} callback - A callback function that allows to process the current 3D object.