I3s 3D Object Layer

<!--
  示例：三维对象图层
  说明：路灯、行道树等重复对象沿道路排布，点击可切换对象显隐
  核心逻辑：Cylinder / Cone 组合 → 阵列排布 → 拾取切换 show
  依赖：CesiumJS 1.121 · jsDelivr CDN
-->
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta name="robots" content="noindex,follow">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>三维对象图层</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/cesium@1.121.0/Build/Cesium/Widgets/widgets.css">
<style>
  html,body{height:100%;margin:0}
  body{background:#0e1116;color:#e6e8ec;overflow:hidden;
       font:13px/1.6 -apple-system,"Segoe UI","PingFang SC",sans-serif}
  #c{height:100%}
  .tip{position:absolute;left:12px;top:12px;z-index:5;
       background:rgba(23,28,35,.9);border:1px solid #2a313b;border-radius:6px;
       padding:8px 12px;font-size:12px;color:#a2a9b6;max-width:320px;line-height:1.6}

  .cesium-viewer-bottom .cesium-widget-credits,.cesium-viewer-animationContainer,
  .cesium-viewer-timelineContainer{display:none!important}
</style>
</head>
<body>
<div id="c"></div>
<div class="tip">沿街的灯杆与树冠是同一套几何，靠阵列摆放形成对象图层。</div>
<script src="https://cdn.jsdelivr.net/npm/cesium@1.121.0/Build/Cesium/Cesium.js"></script>
<script>
(function () {
  'use strict';

  var viewer = new Cesium.Viewer('c', {
    baseLayer: false,
    baseLayerPicker: false, geocoder: false, homeButton: false,
    sceneModePicker: false, navigationHelpButton: false,
    animation: false, timeline: false, fullscreenButton: false,
    infoBox: false, selectionIndicator: false
  });

  var scene = viewer.scene;
  scene.globe.baseColor = Cesium.Color.fromCssColorString('#1c2733');
  scene.backgroundColor = Cesium.Color.fromCssColorString('#0e1116');
  scene.skyBox.show = false;
  scene.sun.show = false;
  scene.moon.show = false;
  if (scene.skyAtmosphere) scene.skyAtmosphere.show = false;

  var objects = [];

  for (var i = 0; i < 16; i++) {
    var lon = 116.3852 + i * 0.00062;
    var lat = 39.9026;

    /* 灯杆 */
    objects.push(viewer.entities.add({
      position: Cesium.Cartesian3.fromDegrees(lon, lat, 4),
      cylinder: {
        length: 8, topRadius: 0.16, bottomRadius: 0.22,
        material: Cesium.Color.fromCssColorString('#8f9aa8')
      }
    }));

    /* 树冠 */
    objects.push(viewer.entities.add({
      position: Cesium.Cartesian3.fromDegrees(lon + 0.00022, lat + 0.00030, 3.4),
      cylinder: {
        length: 6.8, topRadius: 0.2, bottomRadius: 0.5,
        material: Cesium.Color.fromCssColorString('#5d4a36')
      }
    }));

    objects.push(viewer.entities.add({
      position: Cesium.Cartesian3.fromDegrees(lon + 0.00022, lat + 0.00030, 8.6),
      ellipsoid: {
        radii: new Cesium.Cartesian3(2.6, 2.6, 3.0),
        material: Cesium.Color.fromCssColorString('#4f7a55')
      }
    }));
  }

  var handler = new Cesium.ScreenSpaceEventHandler(scene.canvas);
  handler.setInputAction(function (click) {
    var picked = scene.pick(click.position);
    if (!Cesium.defined(picked) || !picked.id) return;
    var idx = objects.indexOf(picked.id);
    if (idx === -1) return;
    picked.id.show = !picked.id.show;
  }, Cesium.ScreenSpaceEventType.LEFT_CLICK);
  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.3952, 39.8992, 120),
    orientation: { heading: Cesium.Math.toRadians(-6), pitch: Cesium.Math.toRadians(-8), roll: 0 },
    duration: 0
  });
})();
</script>
</body>
</html>