Czml Polyline Volume

<!--
  示例：CZML 折线体挤出管道
  说明：shape 给出矩形截面，positions 给中心线，cornerType 控制转角处理
  核心逻辑：shape.cartesian2 是米为单位的二维轮廓 → 沿中心线挤出 → CzmlDataSource.load
  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>CZML 折线体</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%}
  .cesium-viewer-bottom .cesium-widget-credits,.cesium-viewer-animationContainer,
  .cesium-viewer-timelineContainer{display:none!important}
</style>
</head>
<body>
<div id="c"></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.moon.show = false;
  if (scene.skyAtmosphere) scene.skyAtmosphere.show = false;
  scene.globe.enableLighting = true;

  /* 中心线：一条折线，含两次转弯 */
  var centerline = [
    116.330, 39.900, 200,
    116.372, 39.918, 260,
    116.386, 39.884, 200,
    116.432, 39.906, 300
  ];

  var data = [
    { id: 'document', name: '折线体', version: '1.0' },
    {
      id: 'pipe-beveled',
      name: '矩形截面 · BEVELED 转角',
      polylineVolume: {
        positions: { cartographicDegrees: centerline },
        shape: {
          cartesian2: [-2600, -2600, 2600, -2600, 2600, 2600, -2600, 2600]
        },
        cornerType: 'BEVELED',
        material: { solidColor: { color: { rgba: [77, 155, 255, 225] } } }
      }
    },
    {
      id: 'pipe-mitered',
      name: '圆形截面 · MITERED 转角',
      polylineVolume: {
        positions: {
          cartographicDegrees: [
            116.330, 39.870, 120,
            116.372, 39.888, 180,
            116.386, 39.854, 120,
            116.432, 39.876, 220
          ]
        },
        shape: {
          cartesian2: [
            3000, 0,
            2121, 2121,
            0, 3000,
            -2121, 2121,
            -3000, 0,
            -2121, -2121,
            0, -3000,
            2121, -2121
          ]
        },
        cornerType: 'MITERED',
        material: { solidColor: { color: { rgba: [57, 192, 160, 225] } } }
      }
    },
    {
      id: 'caption',
      position: { cartographicDegrees: [116.386, 39.846, 0] },
      label: {
        text: '上：矩形截面　下：八边形近似圆',
        font: '500 13px "Microsoft YaHei", sans-serif',
        fillColor: { rgba: [216, 230, 246, 255] },
        disableDepthTestDistance: Number.POSITIVE_INFINITY
      }
    }
  ];

  Cesium.CzmlDataSource.load(data).then(function (ds) {
    viewer.dataSources.add(ds);
  });

  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.386, 39.838, 30000),
    orientation: {
      heading: 0,
      pitch: Cesium.Math.toRadians(-40),
      roll: 0
    },
    duration: 0
  });
})();
</script>
</body>
</html>