GLTFLoader

• Use load(url, onLoad, onProgress, onError) or loadAsync(url) to fetch the asset.
• setDRACOLoader() and setKTX2Loader() must be called before load() for compressed files.
• parse() accepts an ArrayBuffer or JSON string without issuing a network request.

const loader = new GLTFLoader();

const gltf = await loader.loadAsync('/models/building.glb', function (event) {
  if (event.lengthComputable) {
    console.log('加载进度', (event.loaded / event.total * 100).toFixed(1) + '%');
  }
});

const model = gltf.scene;
model.traverse(function (obj) {
  if (obj.isMesh) {
    obj.castShadow = true;
    obj.receiveShadow = true;

    if (obj.material && obj.material.map) {
      obj.material.map.anisotropy = renderer.capabilities.getMaxAnisotropy();
    }
  }
});

scene.add(model);
if (gltf.animations.length) {
  const mixer = new THREE.AnimationMixer(model);
  mixer.clipAction(gltf.animations[0]).play();
  mixers.push(mixer);
}

import { DRACOLoader } from 'three/addons/loaders/DRACOLoader.js';
import { KTX2Loader } from 'three/addons/loaders/KTX2Loader.js';

const draco = new DRACOLoader();
draco.setDecoderPath('/wasm/draco/');

const ktx2 = new KTX2Loader()
  .setTranscoderPath('/wasm/basis/')
  .detectSupport(renderer);

loader.setDRACOLoader(draco);
loader.setKTX2Loader(ktx2);

• Draco or KTX2 assets fail at runtime if the matching decoder was not attached first.
• Removing a loaded model does not free geometry or textures; call dispose() explicitly.