Washington Dc 2017

<!--
  示例：纪念性建筑群
  说明：中轴对称的低层建筑群加广场水景，呈现规划式的城市布局
  核心逻辑：对称布局体块 → 中央水池 → 轴线路网
  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>纪念性建筑群</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/cesium@1.121.0/Build/Cesium/Widgets/widgets.css">
<style>
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  .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">建筑沿中轴对称展开，中间是长条水池与轴线道路。</div>
<script src="https://cdn.jsdelivr.net/npm/cesium@1.121.0/Build/Cesium/Cesium.js"></script>
<script>
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  var viewer = new Cesium.Viewer('c', {
    baseLayer: false,
    baseLayerPicker: false, geocoder: false, homeButton: false,
    sceneModePicker: false, navigationHelpButton: false,
    animation: false, timeline: false, fullscreenButton: false,
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  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 originLon = 116.3895, originLat = 39.9035;

  /* 沿中轴两侧对称放置低层建筑 */
  for (var i = 0; i < 6; i++) {
    [-1, 1].forEach(function (side) {
      var h = 22 + (i % 3) * 6;
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        position: Cesium.Cartesian3.fromDegrees(
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        box: {
          dimensions: new Cesium.Cartesian3(54, 40, h),
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          outlineColor: Cesium.Color.fromCssColorString('#8d949c')
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    position: Cesium.Cartesian3.fromDegrees(originLon, originLat + 0.0016, 62),
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  /* 中央水池 */
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        originLon - 0.0006, originLat - 0.0022,
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      height: 0.6,
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      outline: true,
      outlineColor: Cesium.Color.fromCssColorString('#cfe2f5')
    }
  });

  /* 轴线道路 */
  viewer.entities.add({
    polyline: {
      positions: Cesium.Cartesian3.fromDegreesArray([
        originLon, originLat - 0.0030,
        originLon, originLat + 0.0028
      ]),
      width: 8,
      clampToGround: true,
      material: Cesium.Color.fromCssColorString('#9aa2ab')
    }
  });
  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.3895, 39.8968, 520),
    orientation: { heading: Cesium.Math.toRadians(-16), pitch: Cesium.Math.toRadians(-20), roll: 0 },
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</body>
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