用ThreeJS动画制作降落伞运动？

Question

I want to do this in Three.JS:

我做了向下运动，但是我没有做左右运动。

var boxGeometry = new THREE.BoxGeometry(5, 5, 5);
var boxMaterial = new THREE.MeshPhongMaterial({color: 0x00ff00, wireframe: false});
boxMesh = new THREE.Mesh(boxGeometry , boxMaterial );

var coneGeometry = new THREE.ConeGeometry(5, 5);
var coneMaterial = new THREE.MeshPhongMaterial({color: 0x0000ff , wireframe: false});
coneMesh = new THREE.Mesh(coneGeometry, coneMaterial);
coneMesh.position.y = 10;

var geometry = new THREE.Geometry();
geometry.vertices.push(
    new THREE.Vector3( 0, 0, 0 ),
    new THREE.Vector3( 5, 7.5, 0 ),
    new THREE.Vector3( 0, 0, 0 ),
    new THREE.Vector3( -5, 7.5, 0 ),
    new THREE.Vector3( 0, 0, 0 ),
    new THREE.Vector3( 0, 7.5, 5 ),
    new THREE.Vector3( 0, 0, 0 ),
    new THREE.Vector3( 0, 7.5, -5 ),
);
var material = new THREE.LineBasicMaterial( 0xFF00C5, 2.0 );
var line = new THREE.LineSegments( geometry, material );

group = new THREE.Group();
group.add(line, boxMesh, coneMesh);
group.position.y = 20;
scene.add(group);

我可以向下移动

group.position.y -= 0.08;
if(group.position.y < 1.6) {
    group.position.y = 20;
}

那么，有人可以帮我左右移动吗？