usdzModel/js/main.js

import * as THREE from "../js/three.module.js";

import initTinyUSDZ from "../js/tinyusdz.js";

import { OrbitControls } from "../js/OrbitControls.js";

const urlAll = window.location.href.split("?m=")[1];

// console.log(123456,urlAll);

const USDZ_FILEPATH = `https://4dkankan.oss-cn-shenzhen.aliyuncs.com/sxz/${urlAll}.usdz`;

document.addEventListener("DOMContentLoaded", async () => {
  const loadingBar = document.getElementById("loading"); // 获取加载条元素
  loadingBar.style.display = "block"; // 显示加载条

  const usd_res = await fetch(USDZ_FILEPATH);
  const totalBytes = parseInt(usd_res.headers.get("Content-Length"), 10); // 获取总字节数
  const reader = usd_res.body.getReader(); // 获取读取器
  const chunks = []; // 存储数据块
  let receivedLength = 0; // 已接收字节数

  let timeOut = -1;

  // 更新加载条的函数
  const updateLoadingBar = (loaded) => {
    let percentage = (loaded / totalBytes) * 100;
    if (percentage >= 100) {
      percentage = 100;
      // 隐藏加载条

      clearTimeout(timeOut);
      timeOut = setTimeout(() => {
        const loadingBoxDom = document.querySelector(".loadingBox");
        loadingBoxDom.style.opacity = 0;
        loadingBoxDom.style.pointerEvents = "none";
      }, 300);
    }

    loadingBar.style.width = `${percentage}%`; // 更新加载条宽度
  };

  // 读取数据流
  while (true) {
    const { done, value } = await reader.read(); // 读取数据
    if (done) break; // 如果读取完成，退出循环
    chunks.push(value); // 存储数据块
    receivedLength += value.length; // 更新已接收字节数
    updateLoadingBar(receivedLength); // 更新加载条
  }

  const usd_data = new Uint8Array(receivedLength); // 创建最终数据数组
  let position = 0;
  for (const chunk of chunks) {
    usd_data.set(chunk, position); // 将数据块写入最终数组
    position += chunk.length; // 更新位置
  }

  // const usd_binary = new Uint8Array(usd_data);

  // 加载 TinyUSDZ
  initTinyUSDZ().then(function (TinyUSDZLoader) {
    const usd = new TinyUSDZLoader.TinyUSDZLoader(usd_data);
    // console.log(usd.numMeshes());

    const scene = new THREE.Scene();
    const camera = new THREE.PerspectiveCamera(
      75,
      window.innerWidth / window.innerHeight,
      0.1,
      1000
    );

    const renderer = new THREE.WebGLRenderer({
      alpha: true, // 关键配置，设置背景透明
      antialias: true, // 可选抗锯齿
    });

    renderer.setClearColor(0x000000, 0); // 第二个参数为透明度（0表示完全透明）

    renderer.setSize(window.innerWidth, window.innerHeight);
    renderer.setAnimationLoop(animate);
    document.body.appendChild(renderer.domElement);

    // First mesh only
    const mesh = usd.getMesh(0);
    //console.log("usd", usd)
    //console.log("mesh", mesh);

    //const geometry = new THREE.BoxGeometry( 1, 1, 1 );
    const geometry = new THREE.BufferGeometry();
    geometry.setAttribute(
      "position",
      new THREE.BufferAttribute(mesh.points, 3)
    );
    // TODO: set normal from mesh

    if (mesh.hasOwnProperty("texcoords")) {
      // console.log(mesh.texcoords);
      geometry.setAttribute("uv", new THREE.BufferAttribute(mesh.texcoords, 2));
    }

    const usdMaterial = usd.getMaterial(mesh.materialId);
    //console.log("usdMat", usdMaterial);
    //if (usdMaterial.aaa) {
    //  console.log("aaa");
    //}

    var material;

    if (usdMaterial.hasOwnProperty("diffuseColorTextureId")) {
      const diffTex = usd.getTexture(usdMaterial.diffuseColorTextureId);

      const img = usd.getImage(diffTex.textureImageId);
      // console.log(img);

      // assume RGBA for now.
      let image8Array = new Uint8ClampedArray(img.data);
      let imgData = new ImageData(image8Array, img.width, img.height);

      const texture = new THREE.DataTexture(imgData, img.width, img.height);
      texture.flipY = true;
      texture.needsUpdate = true;

      material = new THREE.MeshBasicMaterial({
        map: texture,
      });
    } else {
      material = new THREE.MeshNormalMaterial();
    }

    // Assume triangulated indices.
    geometry.setIndex(
      new THREE.Uint32BufferAttribute(mesh.faceVertexIndices, 1)
    );

    geometry.computeVertexNormals();

    //const material = new THREE.MeshBasicMaterial( { color: 0x00ff00 } );
    const cube = new THREE.Mesh(geometry, material);

    // 缩放模型
    cube.scale.set(2, 2, 2);
    cube.updateMatrixWorld(true); // 强制更新世界矩阵[3](@ref)

    // 计算包围盒
    const box = new THREE.Box3().setFromObject(cube);
    const center = new THREE.Vector3();
    box.getCenter(center);

    // 居中模型
    cube.position.sub(center);

    // 计算尺寸并调整相机
    const size = box.getSize(new THREE.Vector3()).length();
    camera.near = size / 100;
    camera.far = size * 100;
    camera.updateProjectionMatrix();
    camera.position.set(size * 0.5, size * 0.5, size * 0.5);
    camera.lookAt(0, 0, 0);

    scene.add(cube);

    //camera.position.z = 25;
    // camera.position.z = 1.0;

    const controls = new OrbitControls(camera, renderer.domElement);

    controls.enablePan = false; // 禁用右键平移功能

    controls.enableZoom = false; // 必须禁用轨道控制器的默认缩放[1](@ref)

    controls.enableDamping = true;
    controls.dampingFactor = 0.25;
    controls.screenSpacePanning = false;
    controls.maxPolarAngle = Math.PI / 2;

    // 兼容鼠标滚轮与触摸屏双指缩放
    const handleZoom = (delta) => {
      // console.log('--------',delta);

      cube.updateMatrixWorld(true);
      // 计算包围盒
      const box = new THREE.Box3().setFromObject(cube);
      const center = new THREE.Vector3();
      box.getCenter(center);

      // 居中模型
      cube.position.sub(center);

      cube.scale.multiplyScalar(delta);
      cube.scale.clampScalar(0.5, 4); // 限制缩放范围0.5-3倍[1,6](@ref)
    };

    // 鼠标滚轮事件
    window.addEventListener(
      "wheel",
      (e) => {
        e.preventDefault();
        const zoomFactor = e.deltaY > 0 ? 0.95 : 1.05;
        handleZoom(zoomFactor);
      },
      { passive: false }
    );

    // 触摸屏双指缩放
    let initialDistance = 0;
    window.addEventListener("touchstart", (e) => {
      if (e.touches.length === 2) {
        initialDistance = Math.hypot(
          e.touches[0].pageX - e.touches[1].pageX,
          e.touches[0].pageY - e.touches[1].pageY
        );
      }
    });

    window.addEventListener("touchmove", (e) => {
      if (e.touches.length === 2) {
        const currentDistance = Math.hypot(
          e.touches[0].pageX - e.touches[1].pageX,
          e.touches[0].pageY - e.touches[1].pageY
        );
        const zoomFactor = currentDistance > initialDistance ? 1.01 : 0.99;
        handleZoom(zoomFactor);
        initialDistance = currentDistance;
      }
    });

    function animate() {
      //cube.rotation.x += 0.01;
      // cube.rotation.y += 0.02;

      controls.update();

      renderer.render(scene, camera);
    }

    window.addEventListener("resize", () => {
      camera.aspect = window.innerWidth / window.innerHeight;
      camera.updateProjectionMatrix();
      renderer.setSize(window.innerWidth, window.innerHeight);
    });
  });
});