Picking

<!--
  示例：deck.gl 拾取高亮
  要点：ScatterplotLayer 开启拾取，点击后用环形与光晕图层标出选中点，并同步信息面板
  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>拾取高亮</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:16px;align-items:center;font-size:12px;color:#8b93a1;flex-wrap:wrap}
  .bar b{color:#58a6ff;font-weight:600}
  .stage{position:relative;flex:1 1 auto;min-height:0}
  #cv{width:100%;height:100%;display:block}
  .panel{position:absolute;left:14px;bottom:14px;min-width:190px;padding:10px 14px;
         background:rgba(16,22,32,0.9);border:1px solid #2c3644;border-radius:8px;
         font-size:12px;line-height:1.9;color:#9aa4b4;pointer-events:none}
  .panel .hd{color:#e6e8ec;font-weight:600;margin-bottom:2px}
  .panel .val{color:#7fc4ff;font-family:ui-monospace,Consolas,monospace}
  .hint{position:absolute;right:14px;bottom:14px;font-size:11px;color:#5f6875}
</style>
</head>
<body>
<div class="bar">
  <span>点位 <b id="n">—</b></span>
  <span>点击任意点选中 · 点击空白取消</span>
</div>
<div class="stage">
  <canvas id="cv"></canvas>
  <div class="panel" id="panel">
    <div class="hd">未选中</div>
    <div>点击画面中的点查看详情</div>
  </div>
  <div class="hint">悬停可预览坐标</div>
</div>
<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 data = [];
  for (var i = 0; i < 6000; i++) {
    data.push({
      id: 'P' + (1000 + i),
      lng: 121.46 + (Math.random() + Math.random() - 1) * 0.12,
      lat: 31.22 + (Math.random() + Math.random() - 1) * 0.09,
      flow: Math.round(20 + Math.random() * 480),
      level: Math.random() > 0.82 ? 2 : 1
    });
  }

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

  var selected = null;
  var panel = document.getElementById('panel');

  function colorOf(d) {
    if (d.level === 2) return [255, 140, 84, 215];
    return [92, 178, 255, 205];
  }

  var pointsLayer = new deck.ScatterplotLayer({
    id: 'points',
    data: data,
    getPosition: function (d) { return [d.lng, d.lat]; },
    getRadius: function (d) { return d.level === 2 ? 4 : 2.4; },
    radiusUnits: 'pixels',
    radiusMinPixels: 2,
    radiusMaxPixels: 8,
    getFillColor: colorOf,
    pickable: true,
    autoHighlight: true,
    highlightColor: [255, 255, 255, 90]
  });

  function haloLayer() {
    return new deck.ScatterplotLayer({
      id: 'halo',
      data: selected ? [selected] : [],
      getPosition: function (d) { return [d.lng, d.lat]; },
      getRadius: 30,
      radiusUnits: 'pixels',
      getFillColor: [90, 190, 255, 55],
      pickable: false
    });
  }

  function ringLayer() {
    return new deck.ScatterplotLayer({
      id: 'ring',
      data: selected ? [selected] : [],
      getPosition: function (d) { return [d.lng, d.lat]; },
      getRadius: 17,
      radiusUnits: 'pixels',
      filled: false,
      stroked: true,
      getLineColor: [255, 255, 255, 235],
      getLineWidth: 2,
      lineWidthUnits: 'pixels',
      pickable: false
    });
  }

  function renderPanel() {
    if (!selected) {
      panel.innerHTML = '<div class="hd">未选中</div><div>点击画面中的点查看详情</div>';
      return;
    }
    panel.innerHTML =
      '<div class="hd">' + selected.id + '</div>' +
      '<div>经度 <span class="val">' + selected.lng.toFixed(5) + '</span></div>' +
      '<div>纬度 <span class="val">' + selected.lat.toFixed(5) + '</span></div>' +
      '<div>流量 <span class="val">' + selected.flow + '</span></div>' +
      '<div>等级 <span class="val">' + (selected.level === 2 ? '重点' : '普通') + '</span></div>';
  }

  var deckgl = new deck.Deck({
    canvas: document.getElementById('cv'),
    width: '100%',
    height: '100%',
    initialViewState: {
      longitude: 121.46,
      latitude: 31.22,
      zoom: 11.2,
      pitch: 38,
      bearing: -10,
      maxPitch: 65
    },
    controller: true,
    layers: [pointsLayer, haloLayer(), ringLayer()],
    getTooltip: function (info) {
      if (!info.object || !info.object.id) return null;
      return info.object.id + ' · 流量 ' + info.object.flow;
    },
    onClick: function (info) {
      selected = info.object && info.object.id ? info.object : null;
      renderPanel();
      deckgl.setProps({ layers: [pointsLayer, haloLayer(), ringLayer()] });
    }
  });

  window.__deck = deckgl;
})();
</script>
</body>
</html>