load(url) {
        return new Promise(resolve => {
            this.require('AMFLoader').then(() => {
                var loader = new THREE.AMFLoader();
                loader.load(url, group => {
                    resolve(group);
                }, undefined, () => {
                    resolve(null);
                });
            });
        });
    }
AMFLoader
@author tengge / https://github.com/tengge1