Lensflare

<!--
  示例：镜头光晕
  说明：太阳进入视野时出现彩色光斑与光环，镜头越正对太阳越强
  核心逻辑：createLensFlareStage() → uniforms.intensity / distortion → 太阳进入视野
  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>镜头光晕</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">光晕只在太阳出现在画面里时生效。转动视角让太阳进入画面。</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;

  scene.sun.show = true;
  scene.sun.glowFactor = 1.5;

  var lensFlare = scene.postProcessStages.add(
    Cesium.PostProcessStageLibrary.createLensFlareStage()
  );
  lensFlare.uniforms.intensity = 2.0;
  lensFlare.uniforms.distortion = 10.0;
  lensFlare.uniforms.ghostDispersal = 0.4;
  lensFlare.uniforms.haloWidth = 0.35;
  lensFlare.uniforms.earthRadius = Cesium.Ellipsoid.WGS84.maximumRadius;
  lensFlare.enabled = true;

  /* 高空视角，让太阳落在地平线附近 */
  viewer.clock.currentTime = Cesium.JulianDate.fromIso8601('2026-06-21T04:20:00Z');
  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.391, 39.907, 3200000),
    orientation: { heading: Cesium.Math.toRadians(90), pitch: Cesium.Math.toRadians(18), roll: 0 },
    duration: 0
  });
})();
</script>
</body>
</html>