Cesium开发三维地图入门

需求:要求将GLTF三维模型放到地图上展示,并且添加各种图标和线进行标注。

 用CesiumJS地图工具实现代码如下:

 

初始化地图:

  Cesium.Ion.defaultAccessToken = 'Your token';
    const imageryProvider = new Cesium.UrlTemplateImageryProvider({
      url: "http://webst01.is.autonavi.com/appmaptile?lang=zh_cn&style=7&x={x}&y={y}&z={z}",
      tilingScheme: new Cesium.WebMercatorTilingScheme(),
      fileExtension: 'png',
      minimumLevel: 0,
      maximumLevel: 20,
    });

    const viewer = new Cesium.Viewer("cesiumContainer", {
      imageryProvider: imageryProvider,
      animation: false,        //是否显示动画控件
      homeButton: false,       //是否显示home键
      geocoder: false,         //是否显示地名查找控件,如果设置为true,则无法查询
      baseLayerPicker: false,  //是否显示图层选择控件
      timeline: false,         //是否显示时间线控件
      fullscreenButton: false,  //是否全屏显示
      scene3DOnly: true,       //如果设置为true,则所有几何图形以3D模式绘制以节约GPU资源
      infoBox: false,           //是否显示点击要素之后显示的信息
      sceneModePicker: false,  //是否显示投影方式控件  三维/二维
      navigationInstructionsInitiallyVisible: false,
      navigationHelpButton: false,     //是否显示帮助信息控件
      selectionIndicator: false,       //是否显示指示器组件
    });

    viewer._cesiumWidget._creditContainer.style.display = "none";

    //添加文字标注
    viewer.imageryLayers.addImageryProvider(new Cesium.WebMapTileServiceImageryProvider({
      url: "http://t0.tianditu.com/cva_w/wmts?service=wmts&request=GetTile&version=1.0.0&LAYER=cva&tileMatrixSet=w&TileMatrix={TileMatrix}&TileRow={TileRow}&TileCol={TileCol}&style=default&format=tiles&tk=dda338577652aefde985448d524c66f4",
      layer: "tdtAnnoLayer",
      style: "default",
      format: "image/jpeg",
      tileMatrixSetID: "GoogleMapsCompatible",
      show: false,
    }));

    viewer.scene.primitives.add(Cesium.createOsmBuildings());
    viewer.scene.highDynamicRange = false;
    viewer.shadows = false;

    createGltfModel("../../data/gltf/NewFile.gltf", 117.628293, 23.798717, 0.0, {
      modelScale: 1, //模型放大倍数
      lightColor: new Cesium.Cartesian3(20.0, 20.0, 20.0), //模型的材质亮度
      position: {
        //地图初始化位置,坐标是3维笛卡尔坐标
        x: -2707823.1735314624,
        y: 5173260.303294086,
        z: 2558159.506208664,
      },
      orientation: {
        heading: 4.735189003200103,
        pitch: -0.4113143959917751,
        roll: 6.2804863005660785,
      },
    });

    function createGltfModel(url, lng, lat, height, {
      modelScale,
      lightColor,
      position,
      orientation
    } = {
        modelScale: 1,
        lightColor: new Cesium.Cartesian3(0, 0, 0),
        position: { x: 0, y: 0, z: 0 },
        orientation: { heading: 0, pitch: 0, roll: 0 }
      }) {
      viewer.entities.removeAll();
      let ellipsoid = viewer.scene.globe.ellipsoid;
      let cart3 = ellipsoid.cartographicToCartesian(Cesium.Cartographic.fromDegrees(lng, lat, height));
      let modelMatrix = Cesium.Transforms.eastNorthUpToFixedFrame(cart3);
      let model = viewer.scene.primitives.add(Cesium.Model.fromGltf({
        url,
        modelMatrix,
        scale: 1,     //放大倍数
        lightColor,//gltf模型加载后比较暗,这个起到增大模型材质亮度的作用
      }));

      let initialPosition = new Cesium.Cartesian3(position.x, position.y, position.z); // 相机的位置
      let homeCameraView = {
        destination: initialPosition, // 相机的位置
        orientation,
      };

      viewer.scene.camera.setView(homeCameraView);

      //设置光照(时间)
      /**
       * 这里涉及到一个知识点:julianDate与Date之间的转换关系(参考文档:https://blog.csdn.net/xiaotian602574436/article/details/78293637)
       * js创建的Date对象是北京时间,但是与JulianDate的日期是不同的,cesium中显示的时间与Date日期的时间是差8个小时。北京时间=JulianDate+8
       * 这个时间是我调试的结果,模型不至于很暗
       * 主要是时间要调到太阳照射到整个模型区域,日期没有多大影响
       */
      let utc = Cesium.JulianDate.fromDate(new Date("2021/02/20 03:40:00"));//UTC
      viewer.clock.currentTime = Cesium.JulianDate.addHours(utc, 8, new Cesium.JulianDate());
    }

 抗锯齿处理:

 //抗锯齿处理
    {
      viewer.scene.fxaa = true
      viewer.scene.postProcessStages.fxaa.enabled = true;
      let supportsImageRenderingPixelated = viewer.cesiumWidget._supportsImageRenderingPixelated;
      if (supportsImageRenderingPixelated) {
        let vtxf_dpr = window.devicePixelRatio;
        while (vtxf_dpr >= 2.0) { vtxf_dpr /= 2.0; }
        viewer.resolutionScale = vtxf_dpr;
      }
    }

添加图片:

 //添加图片
    {
      const iconMarks = [
        {
          id: 'factory1',
          position: [117.62514171688602, 23.800514411219126, 40],
          image: '../../data/icons/废气-C.png',
        },
        {
          id: 'factory2',
          position: [117.62441672316956, 23.801488899527932, 40],
          image: '../../data/icons/废气-C.png',
        },
        {
          id: 'camera1',
          position: [117.62438331048037, 23.80172986514075, 20],
          image: '../../data/icons/摄像头-C.png',
          width: 13,
          height: 18
        },
        {
          id: 'camera2',
          position: [117.6251283858732, 23.801983468675637, 10],
          image: '../../data/icons/摄像头-C.png',
          width: 13,
          height: 18
        }
      ];

      for (const mark of iconMarks) {
        let width = mark.width || 30;
        let height = mark.height || 30;
        viewer.entities.add({
          id: mark.id,
          name: 'mark',
          position: Cesium.Cartesian3.fromDegrees(...mark.position),
          billboard: {
            // 图像地址,URI或Canvas的属性
            image: mark.image,
            // 设置颜色和透明度
            // color: Cesium.Color.WHITE.withAlpha(1),
            // 高度(以像素为单位)
            height,
            // 宽度(以像素为单位)
            width,
            // 逆时针旋转
            rotation: 0,
            // 大小是否以米为单位
            sizeInMeters: false,
            // 相对于坐标的垂直位置
            verticalOrigin: Cesium.VerticalOrigin.CENTER,
            // 相对于坐标的水平位置
            horizontalOrigin: Cesium.HorizontalOrigin.LEFT,
            // 该属性指定标签在屏幕空间中距此标签原点的像素偏移量
            pixelOffset: new Cesium.Cartesian2(-width / 2, -height / 2),
            // 应用于图像的统一比例。比例大于会1.0放大标签,而比例小于会1.0缩小标签。
            scale: 1.0,
            // 是否显示
            show: true
          }
        });
      }
    }

添加线:

 //添加线
    {
      const markLines = [
        {
          id: 'line1',
          positions: [[117.62514171688602, 23.800514411219126, 0], [117.62514171688602, 23.800514411219126, 40]],
        },
        {
          id: 'line2',
          positions: [[117.62441672316956, 23.801488899527932, 0], [117.62441672316956, 23.801488899527932, 40]],
        },
        {
          id: 'line3',
          positions: [[117.62441672316956, 23.801488899527932, 20],
          [117.62438331048037, 23.80172986514075, 20],
          [117.6251283858732, 23.801983468675637, 10],
          [117.62516689671625, 23.802117335288763, 10]]
        }
      ];

      for (const line of markLines) {
        let polyline = new Cesium.PolylineGraphics();
        polyline.material = new Cesium.ColorMaterialProperty(new Cesium.Color(0.18, 0.67, 1, 1));
        polyline.width = new Cesium.ConstantProperty(2);
        polyline.arcType = new Cesium.ConstantProperty(
          Cesium.ArcType.NONE
        );
        let coordArr = line.positions.map(e => Cesium.Cartesian3.fromDegrees(...e));
        console.log('coordArr', coordArr);
        polyline.positions = new Cesium.ConstantProperty(coordArr);
        let entity = new Cesium.Entity({
          id: line.id,
          show: true,
          polyline,
          name: 'line',
        });
        viewer.entities.add(entity);
      }
    }

添加事件:

//事件
    {
      let handler = new Cesium.ScreenSpaceEventHandler(viewer.scene.canvas);
      handler.setInputAction(function (evt) {
        let pick = viewer.scene.pick(evt.position);
        // //选中某模型   pick选中的对象
        if (pick && pick.id) {
          alert(pick.id._id)
        }
        let cartesian = viewer.camera.pickEllipsoid(evt.position, viewer.scene.globe.ellipsoid);
        let cartographic = Cesium.Cartographic.fromCartesian(cartesian);
        let lng = Cesium.Math.toDegrees(cartographic.longitude);//经度值
        let lat = Cesium.Math.toDegrees(cartographic.latitude);//纬度值
        let mapPosition = { x: lng, y: lat, z: cartographic.height };//cartographic.height的值始终为零。
        // console.log('mapPosition: ', mapPosition);
        console.log('lng: ', lng, 'lat: ', lat);

      }, Cesium.ScreenSpaceEventType.LEFT_CLICK);

      handler.setInputAction(evt => {
        let pick = viewer.scene.pick(evt.endPosition);
        // //选中某模型   pick选中的对象
        if (pick && pick.id && pick.id._name === 'mark') {
          // console.log('pick', pick.id._id);
          viewer._container.style.cursor = 'pointer';

        } else {
          viewer._container.style.cursor = '';
        }
      }, Cesium.ScreenSpaceEventType.MOUSE_MOVE)
    }

 

 

效果:

Cesium开发三维地图入门

 

 

 

 
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