铯:根据缩放级别显示/隐藏标签

时间:2018-07-10 15:21:41

标签: javascript label zoom cesium

当缩放比例增加到一定水平时,我想隐藏地图的标签。

对于此示例,我想在缩放级别5之后隐藏与collection1相关的所有标签: https://codepen.io/ollazarev/pen/XBWEEq

let viewer = new Cesium.Viewer('cesiumContainer', {
  animation: false,
  baseLayerPicker: false,
  fullscreenButton: false,
  geocoder: false,
  homeButton: false,
  infoBox: false,
  sceneModePicker: false,
  timeline: false,
  navigationHelpButton: false,
  navigationInstructionsInitiallyVisible: false,
});

let collection1 = new Cesium.LabelCollection();
collection1.add({
  position: Cesium.Cartesian3.fromDegrees(-101.678, 57.7833),
  text: 'Canada',
});
collection1.add({
  position : Cesium.Cartesian3.fromDegrees(-75.1641667, 39.9522222),
  text: 'Philadelphia',
});
viewer.scene.primitives.add(collection1);

let collection2 = new Cesium.LabelCollection();
collection2.add({
  position: Cesium.Cartesian3.fromDegrees(-74.0059728, 40.7127753),
  text: 'New York',
});
collection2.add({
  position : Cesium.Cartesian3.fromDegrees(-79.38318429999998, 43.653226),
  text: 'Toronto',
});
viewer.scene.primitives.add(collection2);

1 个答案:

答案 0 :(得分:1)

Cesium的3D相机并没有意识到“缩放级别”,但是您可以使用translucencyByDistance在距离一定距离后关闭标签。

例如,这是您的演示,其中在每个标签上都添加了translucencyByDistance

let viewer = new Cesium.Viewer('cesiumContainer', {
  animation: false,
  baseLayerPicker: false,
  fullscreenButton: false,
  geocoder: false,
  homeButton: false,
  infoBox: false,
  sceneModePicker: false,
  timeline: false,
  navigationHelpButton: false,
  navigationInstructionsInitiallyVisible: false,
});

let collection1 = new Cesium.LabelCollection();
collection1.add({
  position: Cesium.Cartesian3.fromDegrees(-101.678, 57.7833),
  text: 'Canada',
  translucencyByDistance : new Cesium.NearFarScalar(6.0e7, 1.0, 7.0e7, 0.0)
});
collection1.add({
  position : Cesium.Cartesian3.fromDegrees(-75.1641667, 39.9522222),
  text: 'Philadelphia',
  translucencyByDistance : new Cesium.NearFarScalar(4.0e7, 1.0, 7.0e7, 0.0)
});
viewer.scene.primitives.add(collection1);

let collection2 = new Cesium.LabelCollection();
collection2.add({
  position: Cesium.Cartesian3.fromDegrees(-74.0059728, 40.7127753),
  text: 'New York',
  translucencyByDistance : new Cesium.NearFarScalar(1.0e7, 1.0, 3.0e7, 0.0)
});
collection2.add({
  position : Cesium.Cartesian3.fromDegrees(-79.38318429999998, 43.653226),
  text: 'Toronto',
  translucencyByDistance : new Cesium.NearFarScalar(3.0e7, 1.0, 5.0e7, 0.0)
});
viewer.scene.primitives.add(collection2);