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three.js绘制地图(平面、曲面)

作者:互联网

加载中国地图json数据

let loader = new THREE.FileLoader();
loader.load('model/chinaJson.json', function (data) {
   let jsonData = JSON.parse(data);
   initMap(jsonData); // 解析并绘制地图
});

绘制曲面地图
image

function initMap( chinaJson ) {
    //创建一个空对象存放对象
    map = new THREE.Object3D();
    map.name = "china";
    // 遍历省份构建模型
    chinaJson.features.forEach( elem => {
      // 新建一个省份容器:用来存放省份对应的模型和轮廓线
      const province = new THREE.Object3D();
      const coordinates = elem.geometry.coordinates;
      coordinates.forEach( multiPolygon => {
        multiPolygon.forEach( polygon => {
          const lineMaterial = new THREE.LineBasicMaterial( { color: 0XF19553 } ); //0x3BFA9E
          const positions = [];
          const linGeometry = new THREE.BufferGeometry();
          for (let i = 0; i < polygon.length; i ++) {
            var pos = lglt2xyz( polygon[i][0], polygon[i][1] );//将经纬度转为3D坐标
            positions.push( pos.x, pos.y, pos.z );
          }
          linGeometry.setAttribute( 'position', new THREE.Float32BufferAttribute( positions, 3 ) );
          const line = new THREE.Line( linGeometry, lineMaterial );
          province.add( line );
        } );
      } );
      map.add( province );
      map.scale.set(5,5,5);
      map.rotation.y = Math.PI;

    } );
    chinaGroup.add(map);
    chinaGroup.rotation.set(0.594, -0.348,-0.062);
    scene.add(chinaGroup);
  }

绘制平面地图
image

/**
   * 描绘中国边界(平面)
   需要传入Json数据
   */
  function initMap(chinaJson)
  {
      //创建一个空对象存放对象
      map = new THREE.Object3D();
      map.name = "china";
      //定义一个球体

      //墨卡托投影转换  将经纬度转为3D坐标值
      const projection = d3.geoMercator().center([104.0,37.5]).scale(80).translate([0,0]);

      chinaJson.features.forEach((elem,index) => {
          //定义一个省份3D对象
          const province = new THREE.Object3D();
          //每个的 坐标 数组
          const coordinates = elem.geometry.coordinates;
          //循环坐标数组
          coordinates.forEach(multiPolygon =>{
              multiPolygon.forEach( polygon =>{
                  const shape = new THREE.Shape();
                  const  lineMaterial = new THREE.MeshBasicMaterial({
                      color:'white'
                  })

                  const lineGeometry = new THREE.Geometry();
                  for(let i = 0; i< polygon.length; i++)
                  {
                      const [x,y] = projection(polygon[i]);
                      if(i === 0)
                      {
                          shape.moveTo(x,-y);
                      }
                      shape.lineTo(x,-y);
                      lineGeometry.vertices.push(new THREE.Vector3(x,-y,4.01));
                  }
                  //拉伸厚度
                  const extrudeSettings = {
                      depth:4,
                      bevelEnabled:false
                  };
                  const geometry = new THREE.ExtrudeGeometry(shape,extrudeSettings);
                  const material = new THREE.MeshBasicMaterial({
                      color:'#02A1E2',
                      transparent:true,
                      opacity:0.6
                  });
                  const material1 = new THREE.MeshBasicMaterial({
                      color:'#3480C4',
                      transparent:true,
                      opacity:0.5
                  });

                  //this.mesh = new THREE.Mesh(geometry,[material,material1]);
                  const line = new THREE.Line(lineGeometry,lineMaterial);
                  // // 设置高度将省区分开来
                  // if (index % 2 === 0) {
                  //     this.mesh.scale.set(1, 1, 1.2);
                  // }
                  // province.add(this.mesh);
                  province.add(line);
              })
          })

          //将geo的属性放到省份模型中
          province.properties = elem.properties;
          if(elem.properties.contorid)
          {
              const [ x,y] = projection(elem.properties.contorid);
              province.properties._centroid =[x,y];
          }
          map.add(province);
          map.scale.set(0.2,0.2,0.2);
      })

      chinaGroup.add(map);
      scene.add(chinaGroup);
  }

标签:province,map,const,THREE,three,add,new,绘制地图,js
来源: https://www.cnblogs.com/huangchun/p/16661275.html