原文链接及内容

原文链接：https://sandcastle.cesium.com/?src=Imagery%20Layers%20Split.html&label=All

效果如下视频所示：

示例代码如下：

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<style>
  @import url(../templates/bucket.css);

  #slider {
    position: absolute;
    left: 50%;
    top: 0px;
    background-color: #d3d3d3;
    width: 5px;
    height: 100%;
    z-index: 9999;
  }

  #slider:hover {
    cursor: ew-resize;
  }
</style>

<div id="cesiumContainer" class="fullSize">
  <div id="slider"></div>
</div>
<div id="loadingOverlay"><h1>加载中...</h1></div>
<div id="toolbar"></div>

关于鼠标事件如下图：

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const viewer = new Cesium.Viewer("cesiumContainer", {
  geocoder: false,
  homeButton: false,
  sceneModePicker: false,
  baseLayerPicker: false,
  navigationHelpButton: false,
  navigationInstructionsInitiallyVisible: false,
  animation: false,
  timeline: false,
  fullscreenButton: false,
  selectionIndicator: false,
  skyBox: false,
  shouldAnimate: true,
  infoBox: false,
  baseLayer: Cesium.ImageryLayer.fromProviderAsync(
    Cesium.ArcGisMapServerImageryProvider.fromUrl(
      "https://services.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer",
    ),
  ),
});
viewer.cesiumWidget.creditContainer.style.display = "none";

const layers = viewer.imageryLayers;
const earthAtNight = Cesium.ImageryLayer.fromProviderAsync(
  Cesium.IonImageryProvider.fromAssetId(3812),
);

// earthAtNight图层仅显示在滑块的左侧
earthAtNight.splitDirection = Cesium.SplitDirection.LEFT;
layers.add(earthAtNight);

// 将滑块位置与分割位置同步
const slider = document.getElementById("slider");
viewer.scene.splitPosition = slider.offsetLeft / slider.parentElement.offsetWidth;

const handler = new Cesium.ScreenSpaceEventHandler(slider);

let moveActive = false;

function move(movement) {
  if (!moveActive) {
    return;
  }

  const relativeOffset = movement.endPosition.x;
  const splitPosition =
    (slider.offsetLeft + relativeOffset) / slider.parentElement.offsetWidth;
  slider.style.left = `${100.0 * splitPosition}%`;
  viewer.scene.splitPosition = splitPosition;
}

//鼠标左键按下或者双指按下时激活移动事件
handler.setInputAction(function () {
  moveActive = true;
}, Cesium.ScreenSpaceEventType.LEFT_DOWN);
handler.setInputAction(function () {
  moveActive = true;
}, Cesium.ScreenSpaceEventType.PINCH_START);

//鼠标移动或者双指触摸屏幕移动时执行move事件
handler.setInputAction(move, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
handler.setInputAction(move, Cesium.ScreenSpaceEventType.PINCH_MOVE);

//鼠标左键抬起或者双指抬起时禁用移动事件
handler.setInputAction(function () {
  moveActive = false;
}, Cesium.ScreenSpaceEventType.LEFT_UP);
handler.setInputAction(function () {
  moveActive = false;
}, Cesium.ScreenSpaceEventType.PINCH_END);