High Dynamic Range

<!--
  示例：高动态范围与色调映射
  说明：光照强度提到 3，高光不再直接死白，色调映射把亮度压回可显示范围
  核心逻辑：scene.highDynamicRange = true → tonemapper = ACES → scene.light.intensity 提高
  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>高动态范围与色调映射</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">HDR 打开后高光有细节，ACES 色调映射让暗部不至于全黑。</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;

  if (scene.highDynamicRangeSupported) {
    scene.highDynamicRange = true;
    scene.postProcessStages.tonemapper = Cesium.Tonemapper.ACES;
  }

  /* 光照强度超过 1，普通渲染会直接死白，HDR 才有细节 */
  scene.light.intensity = 3.0;

  /* 一排球体：受光面、背光面与地面阴影一起看 */
  for (var i = 0; i < 7; i++) {
    viewer.entities.add({
      position: Cesium.Cartesian3.fromDegrees(116.3875 + i * 0.0014, 39.9055, 5),
      ellipsoid: {
        radii: new Cesium.Cartesian3(4, 4, 4),
        material: new Cesium.ColorMaterialProperty(Cesium.Color.fromCssColorString('#b9c6d6'))
      }
    });
  }
  viewer.camera.flyTo({
    destination: Cesium.Cartesian3.fromDegrees(116.3910, 39.9000, 120),
    orientation: { heading: Cesium.Math.toRadians(10), pitch: Cesium.Math.toRadians(-12), roll: 0 },
    duration: 0
  });
})();
</script>
</body>
</html>