Screen Grid

<!--
  示例：屏幕网格聚合
  要点：ScreenGridLayer 以像素为单元统计密度，格子大小不随缩放变化
  依赖：deck.gl 9.0 · 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>屏幕网格聚合</title>
<style>
  html,body{height:100%;margin:0;background:#0d1117}
  body{display:flex;flex-direction:column;overflow:hidden;
       font:13px/1.6 -apple-system,"Segoe UI","PingFang SC",sans-serif;color:#e6e8ec}
  .bar{position:relative;z-index:5;flex:0 0 auto;padding:8px 12px;background:#161b22;border-bottom:1px solid #252c36;
       display:flex;gap:14px;align-items:center;font-size:12px;color:#8b93a1;flex-wrap:wrap}
  .bar b{color:#58a6ff;font-weight:600}
  .bar label{display:flex;align-items:center;gap:5px;cursor:pointer}
  .bar input[type=checkbox]{accent-color:#4f9ef8}
  .bar input[type=range]{width:150px;accent-color:#4f9ef8}
  .bar button{font:inherit;font-size:12px;padding:3px 10px;border-radius:4px;cursor:pointer;
       border:1px solid #2f3947;background:#1d242e;color:#c9d3e0}
  .bar button:hover{background:#26303d}
  #cv{flex:1 1 auto;min-height:0;width:100%;display:block}

</style>
</head>
<body>
<div class="bar"><span>点数 <b id="n">—</b></span><span>格子 16 px · 缩放观察密度变化</span></div>
<canvas id="cv"></canvas>
<script src="https://cdn.jsdelivr.net/npm/deck.gl@9.0.35/dist.min.js"></script>
<script>
(function () {
  'use strict';

  if (typeof deck === 'undefined') {
    document.body.innerHTML =
      '<div style="padding:24px;color:#ff8c74">deck.gl 加载失败，请检查能否访问 cdn.jsdelivr.net</div>';
    return;
  }
  var pts = [];
  for (var i = 0; i < 20000; i++) {
    var c = i % 5;
    var cx = 116.26 + c * 0.055;
    var cy = 39.84 + (c % 2) * 0.06;
    pts.push({
      lng: cx + (Math.random() + Math.random() - 1) * 0.035,
      lat: cy + (Math.random() + Math.random() - 1) * 0.028,
      w: 1 + Math.random() * 3
    });
  }

  document.getElementById('n').textContent = pts.length.toLocaleString();

  var deckgl = new deck.Deck({
    canvas: 'cv',
    width: '100%',
    height: '100%',
    initialViewState: { longitude: 116.36, latitude: 39.89, zoom: 10.4, pitch: 0, bearing: 0 },
    controller: true,
    layers: [
      new deck.ScreenGridLayer({
        id: 'screen-grid',
        data: pts,
        getPosition: function (d) { return [d.lng, d.lat]; },
        getWeight: function (d) { return d.w; },
        cellSizePixels: 16,
        colorDomain: [0, 60],
        colorRange: [
          [22, 38, 82, 120],
          [28, 96, 150, 165],
          [60, 168, 176, 195],
          [250, 200, 90, 215],
          [232, 92, 62, 235]
        ],
        pickable: true
      })
    ],
    getTooltip: function (info) {
      if (!info.object) return null;
      return '格内权重 ' + (info.object.value || 0).toFixed(1);
    }
  });
  window.__deck = deckgl;
})();
</script>
</body>
</html>