3d 地图进场特效以及地图边缘动画
代码仓库：
King/threejs-3d-map
地图边缘动画核心代码：
const initBorderPoint = () => {// 获取地图边界的左边（通过https://datav.aliyun.com/portal/school/atlas/area_generator#2.51/104.299012/33.447963 获取）let borderPoints3Array = borderMap.features[0].geometry.coordinateslet borderPoints = []borderPoints3Array.forEach((coordinate) => {coordinate.forEach((rows) => {rows.forEach(v => {// 将坐标转化为 d3的坐标const [x_XYZ, y_XYZ] = d3.geoMercator().center([109, 34.5]).scale(1000).translate([0, 0])(v)borderPoints.push({x: x_XYZ, y: -y_XYZ})// 将转换后的坐标放入到一个数组存储起来（重点！！！）linePoints.push([x_XYZ, -y_XYZ, 32])})});});opacityGeometry = new THREE.BufferGeometry();// 将数组转化为一维数组positions = new Float32Array(linePoints.flat(1));// 然后3个一组opacityGeometry.setAttribute("position", new BufferAttribute(positions, 3));opacity = new Float32Array(positions.length).map(() => 0);opacityGeometry.setAttribute("aOpacity", new BufferAttribute(opacity, 1));// 控制 颜色和粒子大小const params = {pointSize: 5.0,pointColor: '#37ffff'}// 看不懂写死const vertexShader = `attribute float aOpacity;uniform float uSize;varying float vOpacity;void main(){gl_Position = projectionMatrix*modelViewMatrix*vec4(position,1.0);gl_PointSize = uSize;vOpacity=aOpacity;}`// 看不懂写死const fragmentShader = `varying float vOpacity;uniform vec3 uColor;float invert(float n){return 1.-n;}void main(){if(vOpacity <=0.2){discard;}vec2 uv=vec2(gl_PointCoord.x,invert(gl_PointCoord.y));vec2 cUv=2.*uv-1.;vec4 color=vec4(1./length(cUv));color*=vOpacity;color.rgb*=uColor;gl_FragColor=color;}`// 创建着色器const material = new THREE.ShaderMaterial({vertexShader: vertexShader,fragmentShader: fragmentShader,transparent: true, // 设置透明uniforms: {uSize: {value: params.pointSize},uColor: {value: new THREE.Color(params.pointColor)}}})// 创建一个点opacityPoints = new THREE.Points(opacityGeometry, material)// 将这个点放入到场景中showScene.add(opacityPoints);
}const render = () => {if (activeProvince === '四川省') {renderer.render(ScScene, camera)let info = document.querySelector('#info')info.style.display = 'none'showScene = ScScene} else {renderer.render(showScene, camera)}if (!activeProvince) {showScene = scenerenderer.render(showScene, camera)}// 如果有地图边界所有坐标if (linePoints && opacity) {// 5234怎么来的：linePoints打印出来我这边有7134个 但是我这边有900个边界点我这边不想显示（也就是我视频下面那一坨很杂碎的地方）所以我截取了5234个//currentPos 也就是数组下标 只去前面5234个点if (currentPos > 5234) {// 移除边缘动画线// showScene.remove(opacityPoints)currentPos = 0;}// 20 就是运动的速度 值越大 移动越快currentPos += 20;// 忘记这是干嘛的for (let i = 0; i < 10; i++) {opacity[(currentPos - i) % linePoints.length] = 0;}// // 忘记这是干嘛的for (let i = 0; i < 100; i++) {opacity[(currentPos + i) % linePoints.length] = i / 50 > 2 ? 2 : i / 50;}// 让点 动起来if (opacityGeometry) {opacityGeometry.attributes.aOpacity.needsUpdate = true;}}// 渲染下一帧的时候会调用render函数requestAnimationFrame(render)tween.update()controls.update()
}进场动画核心代码：
const tween = new Tween({x: 1000, y: 1000, z: 2000}) // 起始位置.to(camera.position, 2000) // 最终位置.easing(Easing.Quadratic.In) // 过度动画.onUpdate((object) => { // 改变摄像机位置camera.position.x = object.xcamera.position.y = object.ycamera.position.z = object.z}).start();主要代码解析：
1、获取边缘地图的所有坐标 转换为 d3坐标
DataV.GeoAtlas地理小工具系列
2、绘制着色器材质(ShaderMaterial)
three.js docs
3、将着色器材质按照地图边界的坐标跑动
4、使用Tween动画库或者 gsap 动画库实现摄像机进场动画
下一篇：
Threejs 实现3D 地图（06）3d 地图飞线动画-CSDN博客
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