/**
 * 将 json 转化为 Object3D
 * @param json
 */
export function fromJSON(json: any): THREE.Object3D;
/**
 * 设置为 ThreeObject 同时，添加 mtl
 * @param json
 * @param mat
 */
export function fromJSON2(json: any, mat: Object): THREE.Object3D;