Czml Path

<!--
  示例：CZML 的 path 自动画出运动轨迹
  说明：对象沿五个城市移动，path 把走过的位置连成线，trailTime 决定尾巴长度
  核心逻辑：clock 推进时间 → position 按采样插值 → path 采样生成轨迹
  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 运动路径</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;

  var start = Cesium.JulianDate.fromIso8601('2026-10-28T00:00:00Z');
  var stop = Cesium.JulianDate.addSeconds(start, 300, new Cesium.JulianDate());

  viewer.clock.startTime = start.clone();
  viewer.clock.stopTime = stop.clone();
  viewer.clock.currentTime = start.clone();
  viewer.clock.clockRange = Cesium.ClockRange.LOOP_STOP;
  viewer.clock.multiplier = 6;
  viewer.clock.shouldAnimate = true;

  var data = [
    {
      id: 'document',
      name: '运动路径',
      version: '1.0',
      clock: {
        interval: '2026-10-28T00:00:00Z/2026-10-28T00:05:00Z',
        currentTime: '2026-10-28T00:00:00Z',
        multiplier: 6,
        range: 'LOOP_STOP',
        step: 'SYSTEM_CLOCK_MULTIPLIER'
      }
    },
    {
      id: 'flight',
      name: '航线',
      availability: '2026-10-28T00:00:00Z/2026-10-28T00:05:00Z',
      position: {
        epoch: '2026-10-28T00:00:00Z',
        interpolationAlgorithm: 'LINEAR',
        interpolationDegree: 1,
        cartographicDegrees: [
          0,   116.39, 39.90, 160000,
          60,  121.47, 31.23, 160000,
          120, 113.26, 23.12, 160000,
          180, 104.06, 30.57, 160000,
          240, 108.95, 34.34, 160000,
          300, 116.39, 39.90, 160000
        ]
      },
      point: {
        pixelSize: 10,
        color: { rgba: [255, 214, 102, 255] },
        outlineColor: { rgba: [20, 24, 30, 255] },
        outlineWidth: 2,
        disableDepthTestDistance: Number.POSITIVE_INFINITY
      },
      path: {
        resolution: 1,
        leadTime: 0,
        trailTime: 120,
        width: 3,
        material: { polylineGlow: { color: { rgba: [255, 196, 80, 255] }, glowPower: 0.2 } }
      },
      label: {
        text: 'trailTime = 120 秒',
        font: '500 12px "Microsoft YaHei", sans-serif',
        fillColor: { rgba: [255, 236, 200, 255] },
        pixelOffset: { cartesian2: [0, -20] },
        disableDepthTestDistance: Number.POSITIVE_INFINITY
      }
    }
  ];

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

  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(112, 30, 8400000),
    orientation: {
      heading: 0,
      pitch: Cesium.Math.toRadians(-52),
      roll: 0
    },
    duration: 0
  });
})();
</script>
</body>
</html>