three.js 使用geojson ,实现中国地图区域,边缘流动效果
在线链接:https://threehub.cn/#/codeMirror?navigation=ThreeJS&classify=expand&id=geoBorder
国内站点预览:http://threehub.cn
github地址: https://github.com/z2586300277/three-cesium-examples
import * as THREE from 'three'
import { OrbitControls } from 'three/examples/jsm/controls/OrbitControls.js'
const box = document.getElementById('box')
const scene = new THREE.Scene()
const camera = new THREE.PerspectiveCamera(75, box.clientWidth / box.clientHeight, 0.1, 1000)
camera.position.set(0, 0, 500)
const renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true, logarithmicDepthBuffer: true })
renderer.setSize(box.clientWidth, box.clientHeight)
box.appendChild(renderer.domElement)
const controls = new OrbitControls(camera, renderer.domElement)
controls.enableDamping = true
scene.add(new THREE.AmbientLight(0xffffff, 1))
const directionalLight = new THREE.DirectionalLight(0xffffff, 2)
directionalLight.position.set(300, 300, 300)
scene.add(directionalLight)
const map = new THREE.TextureLoader().load(`https://file.threehub.cn/` + 'images/channels/lmap.png')
map.wrapS = THREE.RepeatWrapping
map.wrapT = THREE.RepeatWrapping
map.needsUpdate = true
animate()
function animate() {
requestAnimationFrame(animate)
map.offset.x += 0.001
controls.update()
renderer.render(scene, camera)
}
window.onresize = () => {
renderer.setSize(box.clientWidth, box.clientHeight)
camera.aspect = box.clientWidth / box.clientHeight
camera.updateProjectionMatrix()
}
/* 边界 */
const group = new THREE.Group()
fetch(`https://file.threehub.cn/` + 'files/json/chinaBound.json').then(r => r.json()).then(res => {
const { features } = res
features.forEach((i) => {
if (i.geometry.type === 'MultiPolygon') i.geometry.coordinates.forEach((j) => j.forEach((z) => createShapeWithCoord(group, z)))
else if (i.geometry.type === 'Polygon') i.geometry.coordinates.forEach((j) => createShapeWithCoord(group, j))
else if (i.geometry.type === 'LineString') i.geometry.coordinates.length > 1 && createShapeWithCoord(group, i.geometry.coordinates)
})
translationOriginForGroup(group)
scene.add(group)
})
function createShapeWithCoord(group, coordinates) {
if (coordinates.length < 1000) return // 设置点数限制 如果点太少则不绘制
const curvePoints = coordinates.map((k) => coordToVector3(k))
const curve = new THREE.CatmullRomCurve3(curvePoints)
const geometry = new THREE.TubeGeometry(curve, curvePoints.length - 1, 1, 40, false)
const material = new THREE.MeshPhongMaterial({ color: 0xffffff , map , transparent: true })
const mesh = new THREE.Mesh(geometry, material)
translationOriginForMesh(mesh)
group.attach(mesh)
}
function coordToVector3(coord, slace = 10000) {
const [lng, lat] = coord
const x = lng * 20037508.34 / 180
const y = Math.log(Math.tan((90 + lat) * Math.PI / 360)) / (Math.PI / 180) * 20037508.34 / 180
return new THREE.Vector3(x / slace, y / slace, 0)
}
function translationOriginForMesh(mesh) {
const boundingBox = new THREE.Box3().setFromObject(mesh)
boundingBox.getCenter(mesh.position)
mesh.geometry.center()
}
// 设置组中心点
function translationOriginForGroup(group) {
const boundingBox = new THREE.Box3().setFromObject(group)
boundingBox.getCenter(group.position)
group.traverse((c) => {
c.isMesh && c.position.sub(group.position)
})
group.position.set(0, 0, 0)
}
/**
* 名称: 地理边界
* 作者: 优雅永不过时 https://github.com/z2586300277
*/