static findNode( root, nodeName ) {

		if ( nodeName === undefined || nodeName === '' || nodeName === '.' || nodeName === -1 || nodeName === root.name || nodeName === root.uuid ) {

			return root;

		}

		// search into skeleton bones.
		if ( root.skeleton ) {

			const bone = root.skeleton.getBoneByName( nodeName );

			if ( bone !== undefined ) {

				return bone;

			}

		}

		// search into node subtree.
		if ( root.children ) {

			const searchNodeSubtree = function ( children ) {

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

					const childNode = children[ i ];

					if ( childNode.name === nodeName || childNode.uuid === nodeName ) {

						return childNode;

					}

					const result = searchNodeSubtree( childNode.children );

					if ( result ) return result;

				}

				return null;

			};

			const subTreeNode = searchNodeSubtree( root.children );

			if ( subTreeNode ) {

				return subTreeNode;

			}

		}

		return null;

	}
Searches for a node in the hierarchy of the given root object by the given
node name.

@static
@param {Object} root - The root object.
@param {string|number} nodeName - The name of the node.
@return {?Object} The found node. Returns `null` if no object was found.