Polygon

<!--
  示例：多边形与拉伸体
  说明：同一组边界点分别做成贴地面与拉伸成柱体，对比两者的高度表现
  核心逻辑：polygon.hierarchy → extrudedHeight → perPositionHeight 与 outline
  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>多边形与拉伸体</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">左边是贴地多边形，右边抬高并拉伸成体块，边界点来自同一组坐标。</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 ring = [116.383, 39.901, 116.389, 39.901, 116.389, 39.906, 116.386, 39.9075, 116.383, 39.906];

  /* 贴地面：只有高度 0 */
  viewer.entities.add({
    polygon: {
      hierarchy: Cesium.Cartesian3.fromDegreesArray(ring),
      height: 0,
      material: Cesium.Color.fromCssColorString('#3f6f9c').withAlpha(0.85),
      outline: true,
      outlineColor: Cesium.Color.fromCssColorString('#cfe2f5')
    }
  });

  /* 拉伸体：底面 0、顶面 90 米 */
  viewer.entities.add({
    polygon: {
      hierarchy: Cesium.Cartesian3.fromDegreesArray(ring.map(function (v, i) {
        return i % 2 === 0 ? v + 0.007 : v;
      })),
      height: 0,
      extrudedHeight: 90,
      material: Cesium.Color.fromCssColorString('#c08040').withAlpha(0.9),
      outline: true,
      outlineColor: Cesium.Color.fromCssColorString('#2a1d10')
    }
  });
  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.3895, 39.9005, 700),
    orientation: { heading: Cesium.Math.toRadians(-18), pitch: Cesium.Math.toRadians(-42), roll: 0 },
    duration: 0
  });
})();
</script>
</body>
</html>