Scatter Labels

<!--
  示例：点与标签
  要点：ScatterplotLayer 与 TextLayer 共用一份数据，标签用像素偏移抬高
  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>点与标签</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>站点 <b id="n">—</b></span><span>点与文字来自同一数组</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 sites = [
    { name: '国贸', lng: 116.46, lat: 39.91, v: 320 },
    { name: '中关村', lng: 116.31, lat: 39.98, v: 260 },
    { name: '望京', lng: 116.48, lat: 40.00, v: 210 },
    { name: '亦庄', lng: 116.51, lat: 39.80, v: 180 },
    { name: '西直门', lng: 116.35, lat: 39.94, v: 240 },
    { name: '五道口', lng: 116.34, lat: 39.99, v: 150 }
  ];

  document.getElementById('n').textContent = sites.length;

  var deckgl = new deck.Deck({
    canvas: 'cv',
    width: '100%',
    height: '100%',
    initialViewState: { longitude: 116.41, latitude: 39.92, zoom: 11.2, pitch: 20, bearing: 0 },
    controller: true,
    layers: [
      new deck.ScatterplotLayer({
        id: 'sites',
        data: sites,
        getPosition: function (d) { return [d.lng, d.lat]; },
        getRadius: function (d) { return Math.sqrt(d.v) / 2.2; },
        radiusUnits: 'pixels',
        radiusMinPixels: 3,
        radiusMaxPixels: 14,
        getFillColor: [255, 190, 100, 230],
        stroked: true,
        getLineColor: [18, 26, 40, 220],
        lineWidthUnits: 'pixels',
        getLineWidth: 1.5,
        pickable: true
      }),
      new deck.TextLayer({
        id: 'site-labels',
        data: sites,
        getText: function (d) { return d.name; },
        getPosition: function (d) { return [d.lng, d.lat]; },
        getSize: 12,
        sizeUnits: 'pixels',
        getColor: [226, 238, 250, 255],
        getPixelOffset: [0, -16],
        getTextAnchor: 'middle',
        getAlignmentBaseline: 'bottom',
        characterSet: '国贸中关村望京亦庄西直门五道口',
        outlineWidth: 0.12,
        outlineColor: [8, 14, 26, 230],
        billboard: true,
        pickable: false
      })
    ],
    getTooltip: function (info) {
      if (!info.object || !info.object.v) return null;
      return info.object.name + ' · ' + info.object.v;
    }
  });
  window.__deck = deckgl;
})();
</script>
</body>
</html>