1. 首先，使用Autodesk Forge API将RVT模型转换为three.JS格式。可以使用以下代码示例：

// Autodest Forge API code to convert RVT model to three.JS format
const forgeToken = 'INSERT YOUR FORGE API TOKEN HERE';
const forgeModelURL = 'INSERT URL TO YOUR RVT MODEL HERE';
const forgeModelURN = 'INSERT THE MODEL URN HERE';

const modelDerivative = new Autodesk.Viewing.ModelDerivativeApi();
const threejsManifest = await modelDerivative.getManifest(forgeToken, forgeModelURN);
const threejsDerivative = threejsManifest.derivatives.find((derivative) => derivative.role === 'threejs')?.urn;
const threejsURL = await modelDerivative.getDerivativeManifest(forgeToken, forgeModelURN, threejsDerivative);
const threejsData = await fetch(threejsURL.urn).then(res => res.json());

// The three.js model can then be loaded and displayed in a viewer for further processing

2. 然后，将three.JS模型转换为USDZ格式。可以使用以下代码示例：

// Convert three.js model to USDZ format
const canvas = document.createElement('canvas');
const context = canvas.getContext('webgl2');

const gltfExporter = new THREE.GLTFExporter();
gltfExporter.parse(threejsData, (gltf) => {
  const loader = new THREE.GLTFLoader();
  loader.parse(gltf, '', (model) => {
    model.scene.traverse((node) => {
      if (node.isMesh) {
        node.material = new THREE.MeshStandardMaterial({
          color: 'white',
          metalness: 1,
          roughness: 1,
        });
        node.material.envMapIntensity = 1;
      }
    });
  
    const exporter = new USDZExporter();
    const arrayBuffer = exporter.parse(model.scene);
    const blob = new Blob([arrayBuffer], { type: 'model/vnd.pixar.usd' });
    const url = URL.createObjectURL(blob);
  
    // The USDZ model can then be downloaded or displayed in a viewer
  });
});

通过以上代码示